wmf62

Bill

65tripleblack

Mark,
Your exhaust sounds great, but I'm not sure what you mean by flutter. I realize that it's not easy to describe and sometimes the phone mike doesn't capture it accurately. If you are coasting and you hear popping in your exhaust then something is wrong: it's too lean on closed throttle or you have an exhaust leak. I don't think you hear popping on the coast......correct?

Do you hear the "fluttering" in this clip? My heads have no heat port and I have no crossover pipe:

MarkC

I do not hear the same noise in yours. Remember, I did not have the flutter with the old intake with the exhaust crossover. Listen to the short video where the camera is pointed at the tach. When I let off the gas you can hear the flutter. I should have the car back in a few hours.

aaronz28

If what you describe as a "flutter" is not gone with the crossover - then its a lean spot related to the larger intake and better flowing exhaust manifolds you now have... you could fatten up the squirter size or go up 2 jet in the primary to see if that works...

I guess I should day that if you didn't fatten up the carb after opening up the exhaust and putting the better intake on - you most certainly are lean.

A crossover tube might mask the noise - but you'll still be lean and should solve that

65tripleblack

I'd go smaller on the idle air bleeds before changing out the mains. The only way to dial in a carb accurately is by using an exhaust gas analyzer. I'd be willing to bet that Mark is dialed in perfectly as far as main jets are concerned.

The noise that I hear is a function of acoustics. I don't hear a lean condition, at all. I think that the noise he's referring to happens for less than a second as soon as the throttle is released and then goes away as the engine continues to coast down to idle speed.

aaronz28

I don't disagree on the gas anaylzer - but years of experience tells me - you reduce back pressure - you need more fuel

i didn't see or read if he has the stock Holley on the car - but if so- they were lean to begin with. Add the larger and ported exhaust manifolds, the much better flowing intake.....

65tripleblack

He has a Holley clone on the engine. It's a 650 cfm mechanical secondary with no choke horn, similar to Quick Fuel whose name escapes me right now. Very nice piece! I'm willing to bet that it's set up "fatter" and much more accurately than a Holley. It probably wet flows more like 700+ cfm.

Compared to Quick Fuel and Mark's brand, Holley is a piece of chit, and Holley's vintage replacements are door stops.

aaronz28

even still - if it were dialed in before - increasing the intake flow and reducing exhaust back pressure will make the engine lean..

The only other thing I could think of would be an intake/vacuum leak - but that would create more of a popping noise not the flutter.... unless the intake leak is on the lifter valley side where its not pulling cold fresh air but hot crank case fumes...

Either way - the crossover might solve the flutter by balancing the exhaust - but not necessarily solve the actual issue.

I'm not even sure the "flutter" is a problem - having no balance between the right/left side is how the FI cars were designed from the factory and they were fine... i do not think the exhaust crossover in the intake manifold for the choke was ever intended as a balance tube per se anyhow.

My FI car does not have a crossover nor do I notice anything out of the ordinary. On the Camaro with the same Z28 Intake and a Stock (but reworked) 4053 holley - i get more of a raspy ness at certain RPMs with the Chambered Exhaust - yet it wasn't noticable at all when I had the standard transverse muffler on it. The chassis dyno showed a lean spot in the exact rpm that the i'd noticed the raspy exhaust note.

Cheers

Frankie the Fink

If my base motor 63 sounded like that I'd be doing my happy dance.

65 fi

The side pipes were not introduced as an option initially

1965 Chevrolet Corvette Options

Code Description Price
898 Genuine Leather Seats $80.70
A01 Soft-Ray Tinted Windows (all glass) $16.15
A02 Soft-Ray Tinted Windshield $10.80
A31 Power Windows $59.20
C07 Auxiliary Hardtop $236.75
C48 Heater & Defroster Deletion (credit) $100.00
C60 Air Conditioning $421.80
F40 Special Front & Rear Suspension $37.70
G80 Positraction Rear Axle $43.05
G91 Special Highway Axle 3.08:1 Ratio $2.20
J50 Power Brakes $43.05
J61 Drum Brakes (substitution credit) $64.50
K66 Transistor Ingnition System $75.35
L75 327-cid/300-hp V8 $53.80
L76 327-cid/365-hp V8 $129.15
L78 396-cid/425-hp V8 $292.70
L79 327-cid/350-hp V8 $107.60
L84 327-cid/375-hp V8 $538.40
M20 4-Speed Manual Transmission $188.30
M22 4-Speed Close-Ratio Manual Transmission $236.95
M35 Powerglide Automatic Transmission $199.10
N03 36-Gallon Fuel Tank $202.30
N11 Off Road Exhaust System $37.70
N14 Side Mount Exhaust System $134.50
N32 Teakwood Steering Wheel $48.45
N36 Telescopic Steering Column $43.05
N40 Power Steering $96.85
P48 Cast Aluminum Knock-Off Wheels $322.80
P91 7.75 x 15 Nylon Black Sidewall Tires $15.70
P92 7.75 x 15 Rayon White Sidewall Tires $31.85
T01 7.75 x 15 Nylon Gold Sidewall Tires $50.05
U69 AM-FM Radio $203.40
Z01 Comfort & Convenience Group $16.15
1965 Chevrolet Corvette Engine Options

Location Of Engine Code: Stamped on the block in front of the right hand cylinder head.

Letter Code Engine Horsepower Torque Transmission Carburetor
HE 8-327 250 350 3 & 4-Speed Manual 4 BC
HF 8-327 * 300 360 4-Speed Manual 4 BC
HG 8-327 + 375 350 4-Speed Manual Fuel Injection
HH 8-327 + # 365 350 4-Speed Manual 4 BC
HI 8-327 250 350 3 & 4-Speed Manual 4 BC
HJ 8-327 * 300 360 4-Speed Manual 4 BC
HK 8-327 + # 365 350 4-Speed Manual 4 BC
HL 8-327 + # 365 350 4-Speed Manual 4 BC
HM 8-327 + # 365 350 4-Speed Manual 4 BC
HN 8-327 + 375 350 4-Speed Manual Fuel Injection
HO 8-327 250 350 Powerglide 4 BC
HP 8-327 * 300 360 Powerglide 4 BC
HQ 8-327 250 350 Powerglide 4 BC
HR 8-327 * 300 360 Powerglide 4 BC
HT 8-327 # 350 360 4-Speed Manual 4 BC
HU 8-327 # 350 360 4-Speed Manual 4 BC
HV 8-327 # 350 360 4-Speed Manual 4 BC
HW 8-327 # 350 360 4-Speed Manual 4 BC
IF 8-396 + # 425 425 4-Speed Manual 2 - 4BC
+ High Lift Camshaft
* High Performance
# Special High Performance

Transmission Codes

Transmission

rsinor

Yes they were, my bet is it is simply a function of the side exhaust arriving, just as the fuelie was being pushed aside by the 396 addition.

65tripleblack

Exactly! There was a short window when those 2 options were both available at the same time. Mid April - early June 1965 perhaps.

Saw you on TV the other day, Roy! Looks like life is still being good to you.

Vettrocious

Roy can probably speak to this, but I believe (and you can see it in the C2 registry) that big blocks started to appear more frequently near the end of March. Not too many fuelies after that...

When did side exhausts become available?

Thanks,

Mike

MikeM

Fuelies were ordered and built all the way to the end of '65 production.

The only '65 sidepipe cars I saw in this neck of the woods were BB's.

65tripleblack

Around vehicle number 15,000 in the 1965 Corvette M.Y.

Fuelie orders became almost nonexistant once the L78 became available. Why? The option price for the truck motor was less than half that of the fuelie. The intent was satisfied in that the death blow was dealt to the TRUE SHP Chevy smallblocks in favor of cheap torque. The SHP smallblock lived on in name only until the arrival of the LT1 in 1970.

Vettrocious

Thanks. Since this thread is really about the sound of these motors, the other day I started both the 63 360 hp car and the 65 375 hp cars right next to each other. I was really surprised at how different the two stock motors sound...

Mike

65tripleblack

The "brains" of those 2 engines are quite a bit different. "Duntov" has less than 1/3 the overlap of the "30-30" and 26/24 degrees less duration.

Vettrocious

While I always loved the sound of my 63s, the 375 motor sounds more serious, mean, even...

Vettrocious

Of course, if you really want correct flutter, you need to get a butterfly valve...

(sorry)

Mike

MarkC

I just got home from the muffler shop. The crossover took the flutter out. It sounds great and I could not be happier with all these mods. Mitch did my work and even though he is in Norfolk I really like this guy. He does all the exhaust work for Fantom Works. He just bought a 1963 Olds Starfire that is in great shape. Now that is a rare car. I appreciate the comments and maybe one day I can find a 65 fuelie with sidepipes to check out the flutter or lack of. Btw, if anybody needs a set of very quite sidepipes I'll sell my old ones.