Dumping The Voodoo

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Dec 28, 2018 | 10:21 PM

#41

sidepipe seeker

Pro

Joined: Feb 2013

Posts: 617

Likes: 74

From: San Francisco Bay Area Ca

Quote:

Originally Posted by Drothgeb

11:1 works good with aluminum heads. But depending on the cam specs, it might not work with the stock cast iron heads.

Drothgeb; You need to learn your Corvette engine history....then you would NOT question that 11:1 & 11:25 to 1 compression ratios ....." it might not work with the stock cast iron heads."....

1963 Chevrolet Engines 11:25 to 1 Compression ratios ALL CAST IRON HEADS

In 1963 each of the four versions of the big V8 had head space 327-cubic-inch displacement, 4″ bore and 3.25″ stroke. The 250-hp standard engine features a single 4-barrel carb, 10.5:1 compression ratio, hydraulic valve lifters and new dual exhaust system. The 300-hp power plant adds a large aluminum 4-barrel carburetor and larger intake valves. Both the 340- and 360-hp engines have cylinder heads with large ports, domed aluminum pistons, 11.25:1 compression, high-

1964 Chevrolet Engines 11:1 Compression Ratios ALL CAST IRON HEADS

1964 Corvette engines have the last six digits of the VIN stamped on the block after the engine number DigitExampleDescription1 to 70001001Sequential Production Number8F or TFlint, MI or Tonawanda, NY9 to 10Carburetion & Transmission

RC = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
RD = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
RE = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and four-barrel carburetor
RF = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
RP = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
RQ = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
RR = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor, and air conditioning
RT = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
RU = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
RX = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
SC = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and a four-barrel carburetor
SD = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and four-barrel carburetor
SK = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, four-barrel carburetor, and air conditioning
SL = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, four-barrel carburetor, and air conditioning

1965 Chevrolet Engines....11:1 Compression ratios ALL CAST IRON HEADS!!!

HE = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
HF = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
HG = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
HH = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and four barrel carburetor
HI = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor
HJ = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
HK = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor, and air conditioning
HL = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HM = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
HN = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
HO = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and fuel injection
HP = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and fuel injection
HQ = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, fuel injection, and air conditioning
HR = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, fuel injection, and air conditioning
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and fuel injection
HU = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, air conditioning, and fuel injection
HV = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and four-barrel carburetor
HW = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor, and air conditioning
IF = 396-cid 425-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor

1966 Chevrolet Engines 11:1 Compression Ratios ....ALL CAST IRON HEADS

1966 Corvette engines have the last six digits of the VIN stamped on the block after the engine number.PositionCharacterDescription1 to 70001001sequential production number8F or TFlint, MI or Tonawanda, NY9 to 10Carburetion & Transmission

HH = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
HR = 327-cid 300-hp V-8 with 10.5:1 compression ratio, automatic transmission, and four-barrel carburetor
HD = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HO = 327-cid 300-hp V-8 with 10.5:1 compression ratio, automatic transmission, and four barrel carburetor
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
HP = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor
KH = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IK = 427-cid 425-hp V-8 with 11.0:1 compression ratio, manual transmission
IL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, four-barrel carburetor
IM = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, four-barrel carburetor
IP = 427-cid 425-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IQ = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Powerglide automatic transmission and four-barrel carburetor
IR = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Powerglide automatic transmission, four-barrel carburetor

1967 Chevrolet Engines First Year for Aluminum Heads ONLY on the L89
11:1 compression ratio STILL on cast iron heads

1967 Corvette engines have the last six digits of the VIN stamped on the block after the engine number.PositionCharacter(s)Description1 to 70001001Sequential Production Number8F or TFlint, MI or Tonawanda, NY9 to 10Carburetion & Transmission

HD = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HE = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HH = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HO = 327-cid 300-hp V-8 with 10.0:1 compression ratio, automatic transmission, and four barrel carburetor
HP = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
HR = 327-cid 300-hp V-8 with 10.0:1 compression ratio, automatic transmission, and four-barrel carburetor
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual or automatic transmission, four-barrel carburetor
IM = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, and four-barrel carburetor
IQ = 427-cid 390-hp V-8 with 10.25:1 compression ratio, automatic transmission, and four-barrel carburetor
IR = 427-cid 390-hp V-8 with 10.25:1 compression ratio, automatic transmission, and four-barrel carburetor
IT = 427-cid 425-hp V-8 with 12.5:1 compression ratio, manual transmission and four-barrel carburetor
IU = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
JA = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetor
JC = 427-cid 400-hp V-8 with 10.25:1 compression ratio, manual transmission, three two-barrel carburetors
JD = 427-cid 400-hp V-8 with 10.25:1 compression ratio, manual transmission, and three two-barrel carburetors
JE = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, three two-barrel carburetors
JG = 427-cid 400-hp V-8 with 10.25:1 compression ratio, automatic transmission, and three two-barrel carburetor
JH = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
KH = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor

1968 Chevrolet Engines L89 engine had aluminum heads 11:1 Compression Ratios STILL on CAST IRON HEADS

1968 Corvette engines have the last six digits of the VIN stamped on the block after the engine numberPositionCharacterDescription1 to 70001001Sequential Production Number8F or TFlint, MI or Tonawanda, NY9 to 10Carburetion & Transmission

HE = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HO = 327-cid 300-hp V-8 with 10.0:1 compression ratio, Turbo Hydra-Matic transmission, and four barrel carburetor
HP = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, four-barrel carburetor
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual or automatic transmission, four-barrel carburetor
IM = 427-cid 400-hp V-8 with 10.25:1 compression ratio, manual transmission, and three two-barrel carburetors
IO = 427-cid 400-hp V-8 with 10.25:1 compression ratio, Turbo Hydra-Matic transmission, and three two-barrel carburetors
IQ = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Turbo Hydra-Matic transmission, and four-barrel carburetor
IR = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetor
IT = 427-cid 430-hp V-8 with 12.5:1 compression ratio, manual transmission and four-barrel carburetor
IU = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors

1969 Chevrolet Engines The L88 had Aluminum heads and a HUGE $$$ Option!!!
Take NOTE that STILL 11:1 Compression Ratios on CAST IRON HEADS

1969 Corvette engines have the last six digits of the VIN stamped on the block after the engine numberPositionCharacterDescription1 to 70001001sequential production number8F or TFlint, MI or Tonawanda, NY9 to 10Carburetion & transmission

HY = 350-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HZ = 350-cid 300-hp V-8 with 10.0:1 compression ratio, Turbo Hydra-Matic (THM) automatic transmission, and four-barrel carburetor
HW = 350-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HX = 350-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
LM = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, four-barrel carburetor
LL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Turbo Hydra-Matic (THM) automatic transmission, and four-barrel carburetor
LQ = 427-cid 400-hp V-8 with 10.25:1 compression ratio, automatic or manual transmission, and three two-barrel carburetors
LO = 427-cid 430-hp V-8 with 12.0:1 compression ratio, manual transmission, and four-barrel carburetor
LV = 427-cid 430-hp V-8 with 12.0:1 compression ratio, Turbo Hydra-Matic automatic transmission and four-barrel carburetor
LR = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
LX = 427-cid 435-hp V-8 with 11.0:1 compression ratio, Turbo Hydra-Matic automatic transmission, three two-barrel carburetors
LP = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
LW = 427-cid 435-hp V-8 with 11.0:1 compression ratio, Turbo Hydra-Matic transmission, and three two-barrel carburetors
LT = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
LU = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetor

.......and that..."Boys and Girls"....is your 11:1+++ compression ratio CAST IRON HEAD/S...lesson for today!!!...

TIME to take Trigger behind the barn....because I believe I've....

:b eatdeadhorse:.....Mark

Last edited by sidepipe seeker; Dec 28, 2018 at 10:37 PM.

Dec 29, 2018 | 12:00 AM

#42

6T2Vette

Thread Starter

Pro

Joined: Nov 2018

Posts: 533

Likes: 177

From: Silicon Valley, Shell Beach, El Centro

Quote:

Originally Posted by 63 340HP

Your posts read like you found a good Machinist who is working to meet your goals.

The Voodoo cam was too mild in duration, a good attribute for early speed density fuel injection systems that needs a stable idle vacuum signal, but a carb system is more forgiving and can tolerate a longer duration cam. You made a good choice to try something from a cam grinder who is local to the machine shop. Schneider has cut a lot of competitive cams. Are you still going with a hydraulic roller cam & lifters?

Yes, I believe so. and roller tipped rockers. These were necessary to clear the inside of my original Corvette aluminum valve covers because of the high lift of the previous Voodoo cam. I plan to use them since I don't know what lift the new Schneider cam will have. I guess I could ask the machinist, but I'd hope he would tell me if I didn't need them.
I've made so many changes in a relatively short time, that at this point, I plan to use the parts I've ordered unless they're definitely counter productive.
Bob

Dec 29, 2018 | 02:05 AM

#43

ghostrider20

Le Mans Master

Joined: Jan 2002

Posts: 8,913

Likes: 283

Quote:

Originally Posted by sidepipe seeker

You are Grossly Mistaken about "Roller Rockers"....Unless you believe you know MORE than the Experts!!!....Mark

https://www.onallcylinders.com/2018/...-gets-answers/

I think SWCDuke qualifies as an “expert”.

Tell me the implications off added weight to the valve train in the higher RPM range?

Dec 29, 2018 | 02:10 AM

#44

ghostrider20

Le Mans Master

Joined: Jan 2002

Posts: 8,913

Likes: 283

Why are you sticking with a hyd cam?

Dec 29, 2018 | 08:18 AM

#45

Drothgeb

Racer

Joined: Apr 2017

Posts: 481

Likes: 109

From: Monrovia MD

Quote:

Originally Posted by sidepipe seeker

RC = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
RD = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
RE = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and four-barrel carburetor
RF = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
RP = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
RQ = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
RR = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor, and air conditioning
RT = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
RU = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
RX = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
SC = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and a four-barrel carburetor
SD = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and four-barrel carburetor
SK = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, four-barrel carburetor, and air conditioning
SL = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, four-barrel carburetor, and air conditioning

1965 Chevrolet Engines....11:1 Compression ratios ALL CAST IRON HEADS!!!

HE = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
HF = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
HG = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
HH = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and four barrel carburetor
HI = 327-cid 250-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor
HJ = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
HK = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor, and air conditioning
HL = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HM = 327-cid 365-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor, and air conditioning
HN = 327-cid 375-hp V-8 with 11.0:1 compression ratio, manual transmission, and fuel injection
HO = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and fuel injection
HP = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission and fuel injection
HQ = 327-cid 250-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, fuel injection, and air conditioning
HR = 327-cid 300-hp V-8 with 10.5:1 compression ratio, Powerglide automatic transmission, fuel injection, and air conditioning
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and fuel injection
HU = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, air conditioning, and fuel injection
HV = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, and four-barrel carburetor
HW = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor, and air conditioning
IF = 396-cid 425-hp V-8 with 11.0:1 compression ratio, manual transmission or special high-performance manual transmission, four-barrel carburetor

HH = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, and four-barrel carburetor
HR = 327-cid 300-hp V-8 with 10.5:1 compression ratio, automatic transmission, and four-barrel carburetor
HD = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HO = 327-cid 300-hp V-8 with 10.5:1 compression ratio, automatic transmission, and four barrel carburetor
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
HP = 327-cid 300-hp V-8 with 10.5:1 compression ratio, manual transmission, four-barrel carburetor
KH = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IK = 427-cid 425-hp V-8 with 11.0:1 compression ratio, manual transmission
IL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, four-barrel carburetor
IM = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, four-barrel carburetor
IP = 427-cid 425-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IQ = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Powerglide automatic transmission and four-barrel carburetor
IR = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Powerglide automatic transmission, four-barrel carburetor

HD = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HE = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HH = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HO = 327-cid 300-hp V-8 with 10.0:1 compression ratio, automatic transmission, and four barrel carburetor
HP = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
HR = 327-cid 300-hp V-8 with 10.0:1 compression ratio, automatic transmission, and four-barrel carburetor
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual or automatic transmission, four-barrel carburetor
IM = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, and four-barrel carburetor
IQ = 427-cid 390-hp V-8 with 10.25:1 compression ratio, automatic transmission, and four-barrel carburetor
IR = 427-cid 390-hp V-8 with 10.25:1 compression ratio, automatic transmission, and four-barrel carburetor
IT = 427-cid 425-hp V-8 with 12.5:1 compression ratio, manual transmission and four-barrel carburetor
IU = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
JA = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetor
JC = 427-cid 400-hp V-8 with 10.25:1 compression ratio, manual transmission, three two-barrel carburetors
JD = 427-cid 400-hp V-8 with 10.25:1 compression ratio, manual transmission, and three two-barrel carburetors
JE = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, three two-barrel carburetors
JG = 427-cid 400-hp V-8 with 10.25:1 compression ratio, automatic transmission, and three two-barrel carburetor
JH = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
KH = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor

HE = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HO = 327-cid 300-hp V-8 with 10.0:1 compression ratio, Turbo Hydra-Matic transmission, and four barrel carburetor
HP = 327-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, four-barrel carburetor
HT = 327-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, four-barrel carburetor
IL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual or automatic transmission, four-barrel carburetor
IM = 427-cid 400-hp V-8 with 10.25:1 compression ratio, manual transmission, and three two-barrel carburetors
IO = 427-cid 400-hp V-8 with 10.25:1 compression ratio, Turbo Hydra-Matic transmission, and three two-barrel carburetors
IQ = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Turbo Hydra-Matic transmission, and four-barrel carburetor
IR = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetor
IT = 427-cid 430-hp V-8 with 12.5:1 compression ratio, manual transmission and four-barrel carburetor
IU = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors

HY = 350-cid 300-hp V-8 with 10.0:1 compression ratio, manual transmission, and four-barrel carburetor
HZ = 350-cid 300-hp V-8 with 10.0:1 compression ratio, Turbo Hydra-Matic (THM) automatic transmission, and four-barrel carburetor
HW = 350-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
HX = 350-cid 350-hp V-8 with 11.0:1 compression ratio, manual transmission, and four-barrel carburetor
LM = 427-cid 390-hp V-8 with 10.25:1 compression ratio, manual transmission, four-barrel carburetor
LL = 427-cid 390-hp V-8 with 10.25:1 compression ratio, Turbo Hydra-Matic (THM) automatic transmission, and four-barrel carburetor
LQ = 427-cid 400-hp V-8 with 10.25:1 compression ratio, automatic or manual transmission, and three two-barrel carburetors
LO = 427-cid 430-hp V-8 with 12.0:1 compression ratio, manual transmission, and four-barrel carburetor
LV = 427-cid 430-hp V-8 with 12.0:1 compression ratio, Turbo Hydra-Matic automatic transmission and four-barrel carburetor
LR = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
LX = 427-cid 435-hp V-8 with 11.0:1 compression ratio, Turbo Hydra-Matic automatic transmission, three two-barrel carburetors
LP = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
LW = 427-cid 435-hp V-8 with 11.0:1 compression ratio, Turbo Hydra-Matic transmission, and three two-barrel carburetors
LT = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetors
LU = 427-cid 435-hp V-8 with 11.0:1 compression ratio, manual transmission, and three two-barrel carburetor

.......and that..."Boys and Girls"....is your 11:1+++ compression ratio CAST IRON HEAD/S...lesson for today!!!...

TIME to take Trigger behind the barn....because I believe I've....

:b eatdeadhorse:.....Mark

Maybe you should re-read my post. It clearly says “depending on cam specs”.

Yes, 11:1 will work with cast iron heads, if, the intake valve closes late enough to lower the dynamic compression to the point that it will work with whatever fuel you plan to use. Using an old school cam with their late closing intake valve and 103 octane fuel, sure 11:1 will work. Although, I do remember guys having problems with their cars knocking back then with 11:1. Also, I’d like to point out that factory specified 11:1 compression back in the 60s, wasn’t necessarily 11:1 either.

The Voodoo cam mentioned in this thread only drops compression 1 1/2 points or so. So running 11:1 compression with it will yield a dynamic compression ratio of ~9.5:1. With full timing, that may work with 103 octane fuel from the 60s, no way it’s going to work with current day 93 octane fuel. A DCR of 9.5:1 is probably not going to work with aluminum heads either.

The current engine in my 61 has 10.9:1 compression (based on CCs measured during assembly). The cam I run drops the DCR to 8.6:1 (215 psi cranking pressure). It runs great with 36 degrees and 93 octane but, it has aluminum heads. Put a set of cast iron heads on it, it’s going to knock big time!

In addition to head material, there are a number of other factors that come into play in creating engine knock too. Combustion chamber shape, piston shape, air temp, quench and etc are a few that come to mind.

Dec 29, 2018 | 08:33 AM

#46

Factoid

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The lesson on compression ratio was interesting as a history lesson, but practically irrelevant today. The great equalizer is the currently available fuel which cannot support the 1960’s engineering without searching for aviation grade or other specialty racing fuels. Also, the list of modern engines with high compression ratios is also irrelevant as they run sophisticated computer controlled engines with knock detectors and variable timing. None of this is relevant to the OP.

This best advice in this thread is to build your engine with components matched to the desired results. That means prioritizing your needs and determining what is most important. It sounds like the OP wants an original looking engine with more power for cruising around with occasional highway driving. This means more of a bias towards low end torque with a flat curve up to around 5,000 rpm. I would think that out of the literally thousands of available sbc cams, there is a stock one available that meets these needs and a custom grind for this application is unnecessary, but what do I know.

Dec 29, 2018 | 08:56 AM

#47

SWCDuke

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Based on the OP's stated criteria the "327 LT-1" configuration is an exact fit, but he's not listening.

Duke

Dec 29, 2018 | 11:30 AM

#48

AZDoug

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From: Camp Verde AZ

C1 of Year Finalist (performance mods) 2019

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And port injection. It can't pre ignite if it isn't in the cylinder yet.
Doug

Quote:

Originally Posted by Factoid

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Dec 29, 2018 | 12:50 PM

#49

vettsplit 63

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From: "You may all go to Hell- and I will go to Texas- Davy Crockett

St. Jude Donor '12

Quote:

Originally Posted by Drothgeb

Good Post! I remember back in the day, even the 250 horse 327s had to run premium fuel or they would rattle. And you are exactly right in pointing out that the so called 11-1 engines really weren't AS ASSEMBLED at the factory. You could get there by decking, milling and using thinner head gaskets, but from the factory a 11-1 small block was more like 10.4-10.5 true c/r

Last edited by vettsplit 63; Dec 29, 2018 at 12:51 PM.

Dec 29, 2018 | 01:11 PM

#50

6T2Vette

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From: Silicon Valley, Shell Beach, El Centro

Quote:

Originally Posted by SWCDuke

Based on the OP's stated criteria the "327 LT-1" configuration is an exact fit, but he's not listening.

Duke

Not fair to say I don't like the LT1 configuration simply because I'm getting one that is custom ground. Schneider is a highly recognized cam manufacturer. I'm sure he must have the specs for the LT-1. My machinist has relayed the changes he has made along with the performance I expect. There may be a good chance Schneider may select a spec similar to that of the LT-1, but if he doesn't, I'll expect something better than the LT-1.
I am reading all the inputs very carefully, and I must admit some of it goes over my head. Some of the suggestions I made to the Machinist is from information I have garnered from member's inputs.
Thanks.
Bob

Dec 29, 2018 | 01:46 PM

#51

63 340HP

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From: Beach & High Desert Southern California

Quote:

Originally Posted by 6T2Vette

In the rpm range you were seeking, up to ~6000 rpm, the extra weight of a roller tip rocker arm will not effect much. The extra mass will not effect much, if any, valve train motion if you match the valve spring to the camshaft. Follow the advice of Scheineder for cam and matched valve springs. Many guy's here like the soft GM springs for a 100,000 mile life with the soft action GM cams, but you need stiffer matched springs to tame the roller lifter mass and the more aggressive cam lobe profile. If you purchased a roller trunion rocker arm like the CompCams current Ultra Pro Magnum, the rocker arm moment of inertia and pivot friction combined is actually less than the stock rocker arm (resulting in a more stable valve train than stock parts).

Expect the Machinist to talk to you about custom length pushrods (a potential need to get the proper rocker arm geometry for the least valve guide friction and wear).

Project creep and design changes can be frustrating, but a few dollars and a few days delay now will return years of trouble free enjoyment later.

Dec 29, 2018 | 03:15 PM

#52

6T2Vette

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You’ve expressed yourself very succinctly, and your last paragraph explains not just my frustration in taking a an older high performance engine and try and attain or preserve its earlier attributes.
I hope to have my car on the road by the end of January. I’m hoping that what I’ve learned from everyone’s inputs will reflect in my car in a positive manner.
Bob

Dec 29, 2018 | 04:52 PM

#53

jet-tech

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From: Grapevine TX

This thread like many camshaft threads has received a lot of responses. Please keep us up to date with camshaft specs from Schneider. I'm going to bet that the duration is going to be similar to the Lanati cam you originally chose.

Dec 29, 2018 | 06:55 PM

#54

6T2Vette

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From: Silicon Valley, Shell Beach, El Centro

Quote:

Originally Posted by jet-tech

Yeah, I'm kinda curious to know how far I was off. Someone mentioned the Lunati Voodoo 201207-11 (or -12) might have been better. I kinda thought the -11 might have been better, but not the -12.
I have the equivalent of the 201207-10 in a non roller in the 327 in my black '56 Chevy, It has the same block bored out .030 with the same flat top pistons. I took a set of "peak" or "pyramid" heads and put in oversized valves (not quite the same as double humps). I used 2.5" Ramshorn headers and 2.5 exhaust pipes out to 14" Dynomax Super Turbo mufflers. My CR was rated at about 9.8 with HP at about 300. I was happy with those specs, and I like the idle and I have the original 3 on the tree with overdrive, I love it, I don't remember if the posi rear end is a 3.36, or 3.55 but it cruises beautifully at 70mph doing 2300RPM. I have burned 40 feet of rubber off the 17X8 Nitto tires without trying too hard..
I have another fully rebuilt 3speed with the B/W OD. Has anyone regressed to this setup? How did '62 Corvettes use their 3 speeds.

Bob

Dec 29, 2018 | 07:32 PM

#55

MikeM

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From: Greenville, Indiana

Quote:

Originally Posted by 6T2Vette

.. in the 327 in my black '56 Chevy, It has the same block bored out .030 with the same flat top pistons. I took a set of "peak" or "pyramid" heads and put in oversized valves (not quite the same as double humps). I used 2.5" Ramshorn headers and 2.5 exhaust pipes out to 14" Dynomax Super Turbo mufflers. My CR was rated at about 9.8 with HP at about 300. I was happy with those specs, and I like the idle and I have the original 3 on the tree with overdrive, I love it, I don't remember if the posi rear end is a 3.36, or 3.55 but it cruises beautifully at 70mph doing 2300RPM. I have burned 40 feet of rubber off the 17X8 Nitto tires without trying too hard..

Bob

I personally believe if you just simply rebuilt the 327/340 to original factory specs, including cam and compression, you'd have been very happy and avoided a lot of anguish, drama and money. 3.36 axle and wide ratio four speed and you'd have been in business.

A stock 340 will lay down 40 feet of black marks but that doesn't mean you have a fast car.

The stock rebuild will give you 100k miles trouble free if done right. Don't know about this other hot rod parts stuff.

Your money, your car.

Dec 30, 2018 | 03:04 AM

#56

6T2Vette

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Quote:

Originally Posted by MikeM

The stock rebuild will give you 100k miles trouble free if done right. Don't know about this other hot rod parts stuff.

Your money, your car.

I personally believe you don't know what you're talking about my friend. The .'62 327ci 340hp couldn't give you 75K trouble free miles when brand new. :-)
Bob.

Dec 30, 2018 | 08:24 AM

#57

SWCDuke

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My '63 327/340 was still running like a scalded cat at 115K miles, but I took it down because I was worried about the con rods, and, indeed, I found that #7 had a very bad crack across the bolt seat, which was a weak point with the first design 327 rods.

Don't fall into the trap of going with an aggressive dynamics camshaft that requires high rate springs. That puts valve train durability in jeopardy. Since the 327 LT-1 config. uses all OE valve train components it has OE reliability, and a useable power bandwidth to 7200 with 80 percent of peak torque at 2000 and OE appearance is nothing to sneeze at.

I hope you take the time to read the 327 LT-1 system engineering and test threads I recommended earlier. There are hundreds of aftermarket can grinds but most have too much overlap for OE manifolds and reduce torque bandwidth relative to the best OE high performance camshafts of which the LT-1 is the best mechanical lifter design. You're better off putting your budget into head massaging and bulletproof rods than spending it on a custom grind, especially if it requires new lobe masters, which are expensive.

Duke

Dec 30, 2018 | 02:27 PM

#58

jet-tech

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From: Grapevine TX

Retro Roller, Hyd or Mech camshaft. This thread is all over the place. Has the Op even decided what type camshaft?

Dec 30, 2018 | 05:45 PM

#59

vettsplit 63

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Joined: Sep 2009

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From: "You may all go to Hell- and I will go to Texas- Davy Crockett

St. Jude Donor '12

Quote:

Originally Posted by 6T2Vette

I personally believe you don't know what you're talking about my friend. The .'62 327ci 340hp couldn't give you 75K trouble free miles when brand new. :-)
Bob.

Bob, I think your experience is like mine. I have owned multiple SHP small blocks, both new and rebuilt from worn out at 25,000 miles. They were run hard and put up wet. We drove the crap out of em, and when they blew up, we rebuilt em if there were enough salvageable pieces The first experience I had was with a 64 365 horse coupe that had 20,000 miles and smoked like a freight train. Previous owner only had two speeds- stopped and WFO. My Dad thought I was stupid for giving $2600 for it in 66.

Dec 30, 2018 | 07:02 PM

#60

MikeM

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Joined: Mar 2003

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From: Greenville, Indiana

Quote:

Originally Posted by vettsplit 63

Sounds like you and Bob could break an anvil. I've known people like that.

I guess I should have said something about exceptions to the rule. I thought we had a mature audience here that didn't have to do a burnout in front of every 14 year old that came pedaling by on his bicycle with his eyes bugged out.

I can't count the number of solid lifter engines I know of that Chevy replaced under the 12/12 warranty because some knuckle head didn't know how to run a piece of equipment. Or didn't care.!

Bob can take this for whatever he thinks it's worth.

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