CorvetteForum - Chevrolet Corvette Forum Discussion

CorvetteForum - Chevrolet Corvette Forum Discussion (https://www.corvetteforum.com/forums/)
-   C3 Tech/Performance (https://www.corvetteforum.com/forums/c3-tech-performance-3/)
-   -   My 396sbc combo; your thoughts (https://www.corvetteforum.com/forums/c3-tech-performance/2078537-my-396sbc-combo-your-thoughts.html)

Guru_4_hire 07-14-2008 09:24 PM

My 396sbc combo; your thoughts
 
I have more time than money right now to philosophize about my 396 combo

I have:
6" billet crower rods
4.03 pistons for a 3.875" crankshaft
96 truck block with a 1 peice Rear main seal
OE rollers
1.6 ratio crower rockers
3 different single planes
crower solid roller lifters
Titan Oil pump
Custom oil pan for above
Holley 650 DP
Holly 750 DP
Edelbrock 600


I am thinking that this is the way I should go:

396 small block (I will buy either a callies compstar or Howards crankshaft)
a Hyd Roller 224/228 at .05 112 LSA camshaft with .544/.554 lift with the 1.6 ratio rockers
Dart pro 1 200cc platinum heads with a 72cc chamber giving me a nice 10.47:1 compression
Some form of a dual plane probably the dart dual plane
I am sort of hoping for 435+hp(1.1hp to CI)

My expectation is a 5500rpm redline shifting around 5200rpm, cruise nicely, drive nicely, and last forever.

I would like to put a richmond 5 speed (2.77, 1.88, 1.46, 1.18, 1 ratios)
and a 2.73 rearend.

Guru_4_hire 07-14-2008 09:25 PM

Pardon me I ramble, and I forgot to thank everybody for their consideration.

CorvetteDave01 07-14-2008 10:36 PM

Sounds like you could put a nice combination together, should be able to get 500 hp pretty easy with the correct heads and intake I would think.

GDaina 07-14-2008 11:01 PM

you are selling yourself short on the rpm and shift points...you should be able to rev to 7k with the solid rollers, maybe 7500.

2000FRCZ19 07-15-2008 03:18 AM

i went with a little more cam with mine. i used a crower hyd. roller that was 236/240 @ .050. the lift with the 1.6 rockers was .594. i also went with a single plane team g intake. i used eagle forged rods and crankshaft along with -5cc srp flat top pistons. i used afr heads that were cut to 72 cc's. numbers looked very good on the d/d sim and others that have done similar builds got very nice real world numbers also. i am going with a 2004r bto level 3 trans and i have 3.73 gears. from your choices it looks like we are after opposite maners from our set ups. i wanted a little more power in the upper and top end and do not mind a little lope at idle. it looks like you want a smooth idle and lower end tq to match your gears. it should be a fun combo. i was going to dyno it right after it was built but decided to wait untill the car was closer to being finished before running it. i should have it fired up in about 3 more months. i went a lot more in detail with the rebuild of the entire car than i had planned on when i was building the motor.
http://i73.photobucket.com/albums/i212/frcz06/75101.jpg
http://i73.photobucket.com/albums/i212/frcz06/75456.jpg

Guru_4_hire 07-15-2008 07:48 AM


Originally Posted by GDaina (Post 1566307021)
you are selling yourself short on the rpm and shift points...you should be able to rev to 7k with the solid rollers, maybe 7500.

I agree that if I used my solid rollers and one of my 3 single planes I could get more RPM out of it.

I want to leave that option open to me, but I would like to mess around with a mild Hyd. Roller first, and then move to an appropriate crane street roller. Probably around the same time I get the heads properly ported.

Guru_4_hire 07-15-2008 07:54 AM


Originally Posted by 2000FRCZ19 (Post 1566308748)
i went with a little more cam with mine. i used a crower hyd. roller that was 236/240 @ .050. the lift with the 1.6 rockers was .594. i also went with a single plane team g intake. i used eagle forged rods and crankshaft along with -5cc srp flat top pistons. i used afr heads that were cut to 72 cc's. numbers looked very good on the d/d sim and others that have done similar builds got very nice real world numbers also. i am going with a 2004r bto level 3 trans and i have 3.73 gears. from your choices it looks like we are after opposite maners from our set ups. i wanted a little more power in the upper and top end and do not mind a little lope at idle. it looks like you want a smooth idle and lower end tq to match your gears. it should be a fun combo. i was going to dyno it right after it was built but decided to wait untill the car was closer to being finished before running it. i should have it fired up in about 3 more months. i went a lot more in detail with the rebuild of the entire car than i had planned on when i was building the motor.
http://i73.photobucket.com/albums/i212/frcz06/75101.jpg

Isnt that always the case. I am currently ripping out the pop up headlights and front bumper as I want to get rid of the vacuum circuit, popup headlight hell, and I am moving to some Fixed fia headlights. Should be arriving shortly. THen I need to buy a new bumper.

I like that motor it looks sexy.

2000FRCZ19 07-15-2008 08:08 AM

i also took out the pop ups, i have a custom set up i am putting back in place. i went hydroboost for the brakes. i also removed the vac tank in the front bumper area. i have lightened the front end on the car by at least 200 lbs since i have started.

LFZ 07-15-2008 09:28 AM

sounds like a mild street machine..but with all those cubes, you could go more cam and still have nice driveability with more power on tap. I would go with a 230ish/240ish hydraulic roller cam on a 112lsa. You know this....like everyone else, just trying to talk you into more power!

Guru_4_hire 07-15-2008 10:17 AM

More power is great as long as it cruises nicely at 1900-2600rpm and I can keep my 5500rpm redline.(existing tachometer)

Since I dont have heads cams or an intake I am pretty flexible.
I would prefer to stay with Dart heads as the exhaust ports are in the right spot and they have the right size chambers. I would like to avoid the problems and lamentations that we can see in the edelbrock head thread.

I think moving to the Dart 215cc heads might be overkill, so I think the Dart 200cc heads will work out nicely.

I could also find a correct Q-jet (didnt have one when I bought the car a decade ago), and put that on. That would be pretty sweet. I could do something with all these wires that hook up to the fool thing that have been laying loose in the engine bay since I got it.

Guru_4_hire 07-15-2008 10:19 AM

I am not much of a power junkie, sure more is better but lets face facts. Real road race cars have 450-550hp in professional series with big ol road race slicks with huge carbon brakes. I have a 35 year old car with skinny tires and wilwood dynalites. There is only so much power that can be effectively (safely) used. I am not Gkull who races regularily and can make all 600 million hp work, nor am I as gifted a drag racer as oliver or 427hotrod.

Engineering to me is, identifying goals and constraints and then making the best damn solution to meet the goals within the bounds of the constraints. Its all about compromises.

So lets look at goals:
Good driving
Good power
Tons o vacuum
Fun


Constraints:
Cruises nicely between 1900-2600rpm
Redline 5500rpm
aluminum heads
stock location exhaust ports
70-72cc chambers
Hyd Roller camshaft
396 small block

Guru_4_hire 07-15-2008 10:28 AM

Oh and I am also trying to decide whether or not I want to retrofit in some billet mains.

More fun notes, the new C6 ZR1 reaches 180 on the Nurinburg ring with 640hp and 604ft lbs of torque.

Mike Culpepper 07-15-2008 02:07 PM

I'm no expert on this, but I think that with a 3.875" stroke and a 6" rod length, you'll end up with the wristpin in the bottom ring land. You can do this, but as I understand it, this is not conducive to long engine life. If all you are looking for with regards to horsepower is 435+, lets say 450 (it's a nice round number), you can do it with a 383 (3.75" stroke) and stock 5.7 inch rods. One more thing, with a 5500 rpm redline, I don't think you'll be able to really take advantage of a 200cc head, even with a 396.

I built a 383 with an assembled short block from Speedomotive for my '67. I topped it of with a pair of AFR 195's which are probably overkill for the cam that is in there now which is a Comp Cams XE268H. Speedomotive said the cast iron crank in my shortblock lost dimensional stability (flexed) at 6,500rpm so shift at 6,000 and the motor would live a long happy life. Seems to be the case so far, but its only been about 3 years.

One more thing, watch your hood clearance with a modern dual plane intake. I'm running an Edelbrock RPM Air Gap and it just barely fits under my '67 big block hood with a drop base air cleaner.

Little Mouse 07-15-2008 02:32 PM

You have no need for billet main caps for in a low rpm low HP engine, the aftermarket block people say there blocks need billet mains if your pushing past 900 hp. Are the eagle/scat cranks cheaper then the callies/ howards cranks ??

Guru_4_hire 07-15-2008 04:51 PM

The compstar crank is $600 and the Howards is $700. The howards crank is 100% made in America. The Compstar crank is supposed to be of better quality than the Eagle crank and Scat doesnt make an appropriate crankshaft.

Guru_4_hire 07-15-2008 04:52 PM

Dang worthless post

Guru_4_hire 07-15-2008 04:53 PM


Originally Posted by Mike Culpepper (Post 1566313831)
I'm no expert on this, but I think that with a 3.875" stroke and a 6" rod length, you'll end up with the wristpin in the bottom ring land. You can do this, but as I understand it, this is not conducive to long engine life. If all you are looking for with regards to horsepower is 435+, lets say 450 (it's a nice round number), you can do it with a 383 (3.75" stroke) and stock 5.7 inch rods. One more thing, with a 5500 rpm redline, I don't think you'll be able to really take advantage of a 200cc head, even with a 396.

I built a 383 with an assembled short block from Speedomotive for my '67. I topped it of with a pair of AFR 195's which are probably overkill for the cam that is in there now which is a Comp Cams XE268H. Speedomotive said the cast iron crank in my shortblock lost dimensional stability (flexed) at 6,500rpm so shift at 6,000 and the motor would live a long happy life. Seems to be the case so far, but its only been about 3 years.

One more thing, watch your hood clearance with a modern dual plane intake. I'm running an Edelbrock RPM Air Gap and it just barely fits under my '67 big block hood with a drop base air cleaner.

It depends on the dual plane. I have a couple drop base air cleaners I can use.

I already have the pistons and rods.

Little Mouse 07-15-2008 05:17 PM

Never had anything better then a 5140 grade steel chevy crank, ran them with whatever grade steel a chevy rod used factory rod bolts, ran them at rpms you don't want to think about for short periods of time. the eagle/scat cranks are 4340 grade it is chinese steel with all the machining done here in the states. Have you ever had a 396 size engine before ??

Guru_4_hire 07-15-2008 05:39 PM

Nope, I have had a 350 L82 POS junk ass motor I want gone.

And the 98 LS1 in my F-body. A 4.8L Gen 3 motor in my 2003 silverado that I sold when the army sent me to Korea, and 2x 2.4L economy cars.

And my LS1 is probably going away as soon as I pay off a couple of random small loans, and replacing it with a small engine car like a loaded Sky redline.

Nobody really makes the right crank for less than $600

Little Mouse 07-15-2008 07:46 PM

In 78 when I lived in little rock I bought a new fully loaded 3/4 ton pickup, also ordered a new 78 vette L/82, 4 speed, 370 rear, list price on the car was $12,400 payment on it was 343.00, I think the pickup payment was around $160.00 Both vehicles had everything you could get. after it came in I kept the car 6 weeks put 500 miles on it. In 78 everyone was so happy to see a change in styling with the new rear window that on the west coast they were paying people $2,000.00 over list for cars brought in from ohter states. I considered taking it out there selling it but I hated the performance of the car so bad I just sold it for what I paid for it, was only out $343.00 for one payment. $343.00 for 500 miles driving is really pretty expensive but I felt lucky just to get rid of that terd vehicle without any big loss like you normally have buying a new car.

If I were you would not use a cam that small in a 396 even for a mild cruiser.


All times are GMT -4. The time now is 02:44 PM.


© 2024 MH Sub I, LLC dba Internet Brands