hy all..

im building a 396 for my 90 6 speed

what would you say to following:

396, based on a GMPP block, new ( and already at home)

Accel Single plane EFI Intake
210cc AFR Competition heads
plenum in "Jeb" style
Cam with about 236/240 .600 lift (not 100 %sure, but around this)

i run the combo through Destop dyno and yield very good streetable results, with lots of torque, also down low

i would prefer 195cc AFR heads, Comp.port, but the only support lift to .550....

also, want to go with a hydraulic roller cam....!!!! is 220lbs seat pressure to much for a hydraulic roller? (thats the springs, that come with the AFR 210´s)

maybe i should refer the book "How to build big inch chevy small block"
theres an 383 street motor, that build 480hp, with a mild cam and single plane efi......and AFR 210´s.........so i think they should be a good match for a 396...but again...

any Input would be nice

best regards

 

Sounds like a strong combo! If I can go out on a limb here and suggest a large cc size (I'm assuming AFR offers a few different sizes)to unshroud your valves.

 

I think your going to be wasting the heads with that Accel SP intake. Those intakes do not flow any air at all compared to a ported SR or MR or better yet a "real single plane" like the victor jr or SR.

As a result, with the heads being a little on the big side for that motor (should try to stick around 190cc, I would go 180cc on a good head before going larger) and not a real good intake, you will be loosing a lot of potentially GOOD power. Remember our 406ci motors with bone stock out of the box AFR 190s went 11.0 and 10.9s on larger motors with SR intakes.

220lb seat pressure also seems a bit on the high side for what your trying to accomplish. Mine are only ~180lbs, with a much larger solid roller. You should be able to order heads with any spring you need or want on them. They will change you more, but its not good to jump to larger heads to just get the springs. Get the right head size, cc, then put the right springs on them.

You don't want to have a mismatched setup. It will not perform real well.

 

this is the Statement a well known forum member(and engine builder) made about the single plane..."For intake you'll run the single plane; a custom fabbed Super Victor is the best but the Accel single plane is the SAME manifold".

i also like the 195ccs better, since they support enough flow, the impacton hp and tq is marginal compared to 210´s

hope AFR can do custom heads

 

AFR can set up the valvetrain per your needs.

As for seat pressure 220# seems crazy......you need to find out what the seat/open pressure should be set at per the cam mfr.

 

Sounds like a direct quote from me...

Anyway, I ran a 11.5:1 396" motor in my '90; same motor that ran 9's on the bottle. An Accel 74041 single plane is the SAME manifold as an Edelbrock Super Victor but with the injector bungs cast in. My 396 with the single plane and big solid roller made 571 hp and 505 tq using heavily worked Canfield 220cc heads; the big cubes want the big heads but on a smaller bore stroker (sub 400", ie., 4" bore) you'll have to turn it. I spun my to 7500 on motor and to 7k on the jug. It's a good combination for a 6-speed as well. A well thought out combination is better than a poorly thought out one. Give me a PM and I'd be happy to discuss what works and what doesn't with you.
-Jeb

 

If you want the AFR's, consider getting them bare and ordering your valve hardware seperately elsewhere. I got their 210's w/ their components. The springs' seat pressures were
Be prepared to wait 3 months for the heads to be made. I guess AFR is getting better ??? but it seems like everyone ends up waiting at least 3 months.
Let us know how it all turns out. Sounds like a kick a** motor.

 

Be prepared to wait 3 months for the heads to be made. I guess AFR is getting better ??? but it seems like everyone ends up waiting at least 3 months.

There was a major discussion on AFR heads a month or two ago. One comment made a number of times was Trick Flow 23's/195CC are much cheaper, readily available, high quality and flow numbers are very close to AFR's. The posters were very happy with them

 

im in the process of building a 396 also..here is my list of parts.

callies dragonslayer 3.875 forged crank
oliver billet stroker rods.6"
wiseco forged custom nos pistons. 10.5/1 cr
comp cams custom grind solid roller. 248/256 @.050 650/670 lift.
brodix m2 cnc ported 215 heads. flow around 305 cfm.
and either miniram or jebs single plane.

should be around 575 hp..the only reason im using the billet rods is im setting it up for a 250 shot..

the brodix heads should be fine for this combo, 7300 rpms. big solid cam.

as far as the seat pressure on your heads.
you should not go over 145 lbs of seat pressure with a hyd roller..
the springs you mentioned are for a solid roller cam..

 

You can use higher spring pressures with a hydraulic roller cam if your cam is a billet steel core. If it is a Comp Cams "ostempered" core, no way you should use springs over 140lbs on the seat. Their ostempered cores cannot handle high spring loads. But a Crane or other billet or induction hardened steel core will easily handle 180 and even 200+ lbs on the seat. What do you think that GM uses for spring loads on their 572 620hp crate engine with .640+ lift all on a hydraulic roller cam

 

No hyd roller cam in the world is going to overcome 200lbs of seat pressure, not to mention probally 600lbs+ open. Its not a factor of the cam cores strength itself, its a factor of oil pressure in the lifter plunger not physicaly being able to overcome the force of the valve spring, its trying to open.
Will

 

screw waiting for 3 months for afrs. i like the brodix better with no wait and better flow #'s, just about the same price as the afr210 cnc ported.

 

I'll have to dis a gree, the single plan will flow...it just won't be a prettly as the other EFI vettes...even a TPI looks better

The dyno is giving you a fib story...for streetable don't go higher than 230/230 roller. Call up compcams for a custom 230/230 .622 lift hyd roller on a 112 (or even 110 lope sep if you have a lowered expectations of streatable).

idle/street tuning will be difficult with 230/230 cam so be ready!

 

you need to go to ski's website and check out the single plane efi conversion jeb did for him.. it is very nice looking.. and is one of the best intakes setups out there.. is just works better with a larger cube engine.

i have a 241/241 cam in my 350.. the low end sucks but i managed to tune it pretty good with a stock ecu. but it idles fair and runs good.
fast ,dfi or big stuff ecu is the way to go..im looking for a good used one. i know ill make more hp.

 

wow

your cam is pretty radical for a 350...

i will sit back and wait until i have the results from the engine shop that calculate my cam....

 

GMs 572/620hp crate engine uses Crane long body hydraulic lifters and springs rated just under 200lbs on the seat. We uses similar spring pressures on our stock eliminator engines for years. But for those applications we use what is commonly called "cheater" lifters. Basically these are hydraulic rollers or flat tappet lifters (depending on model year of the engine) that has been modified with different internals. They have about .020 of hydraulic movement and after that the lifters are basically solids. Schubeck racing now makes them, the ones I use are modified by Allen Sherman. It really isn't a matter of core strenght per say, but rather a matter of the heat treating and metallurgy of the core. Comps ostempered cores can't handle the heavy spring loads regardless if its a solid or a roller cam. Thats why solid roller cams are all made from billet steel cores.

 

Thats my point, the fore mentioned crate motor has a camshaft that is 258/262 @.050 and it does not use normal hyd lifters. Its not really a hyd cam at all. I have also used Schubeck lifters (both hyd and their mech roller replacement) in a number of oval track motors where we were forced to run "hyd cams" and before they were in business we modified our own hyd lifters as described effectivily making the mech lifters. I rember when he showed up at PRI with those damn ceramic things, I think we bought 2 sets on the spot and, shortly after their introduction they got banned from NASCAR. Exellent prouduct BTW.
I was merely pointing out you cannot put 200lbs of seat pressure on a regular hyd lifter and expect it to work b/c it won't. As for modifying the stock hyd roller lifters personally I think the bearings and pin in the roller itself is mighty damn small to handle that kind of pressure. But hey if you made it work, good on you in my book.
Will

 

Guys.

I think talking about motor applications much larger/different than what the gentleman is inquiring about is only going to confuse matters more.

The spring pressure that you mentioned and I addessed early on is TOO much for what your trying to do with that motor. Nascar and other applications to do apply.

My best recommondation would be look at some of the good running 383-406 applications here on the board and model your setup after them....their really is not difference between 383-406ci motors in terms of what they should run like. If they are all built good, they will all run within a few tenths of one another. Point in hand, 85vet's 383 ran/runs nearly what our 406 motors ran.

There are many examples of good running motors here in that CI range, that I would look into and run the same components as close as you possibly can. That is the easiest way to get where you want to without a lot of grief.

Here are some of the setup I would look at.

corvette0096
Ralphs 406 ci motor
85vet 383 ci motor
Insanities 396 motor
Ski/Corkys 406 motors

And I am sure there are others that can you look at too that I may have missed, but those are some VERY strong running motors that are proven time and time again they can run effectively on the street and perform with the best of them at the track. That is what I think your looking for in your setup.

 

hi all

want to say thank you for your statements..finally my engine is coming together..i will keep you informed on the progress if you want so.......