96ssindeed

So I've been kicking around motor ideas for my rx7, and may just use my old 350. I've been looking around at parts to rebuild it and have decided on going with a little bore, forged scat I beams, and some forged pistons. I'm looking at going about 11.5-1 compression and maybe running a 150 shot later. Id like to make about 450 or so to the flywheel on motor. Was wondering what heads and cam could work? Trickflow, afr? I like the lunati voodoo series cams but would use a custom if that would be more practical. I'm already prepared to use a victor or super victor intake and 750 or so carb. The setup will be in front of a turbo 350.

SSellers

AFR-195's, under 10:1 compression, and an RPM Air Gap will get there with a hyd roller cam in the mid 230's @0.050" and low 0.5xx's lift, and will near about run on regular. SBC's aren't as gifted as LS1's but they're not that hard to get power out of. Putting really good heads on props them up a good bit.

96ssindeed

Ive been looking at afrs but have been seeing good things with tge trickflows as well. Why would you keep ir under 10:1? We have 93 in the pumps here just for reference.

ZONES89RS

iTrader: (25)

10.5-11:1 with the AFR heads mentioned and a custom cam will make it happen. But I vote LS swap. Lol

Think the pro comp heads can be ground on to flow ok.

SSellers

For 450hp, there's just no need to go to 11.5 compression. On an carbed SBC with 11.5:1 you'd have to run a cam with advertised duration of around 300 dedgrees just to get the dynamic compression down to where you could run premium pump gas. You can build a "mild" 9.5-10.1 355ci with 450hp that will have good street manners, good vacuum, and is easy on parts. Knowing the rear gear and intended use would be good to have as well.

If you're building a primary strip car, have at it. But if it's mostly street I can tell you that a SBC with Victor Jr and 300 degree cam needs a lot of stall and gear with an auto and it can be finicky.

96ssindeed

Thanks for all the info. It has 4.10 rear stock and id probably run a 3000-3600 stall on it. It is goibg to be more of a street beater. I like what your saying about having good street manners. Its going to be something I can hop in and cruise around and pick in unsuspecting newer cars lol. I think around 450 with a shot is going to be pretty nasty

SSellers

Well, if you're going to run a 4.10 without OD might as well take advantage of it. I'd give Chris Straub a call, tell him you want to build a 450hp 355 with AFR heads, give him your drivetrain info, and see what he thinks.
http://www.straubtechnologies.com/custom-camshafts/

96ssindeed

Something to think about. Thanks

wht97ws6ta

No need for that much compression. I built a 355 stock bottom half with some old trw forged pistons. Really no trick parts in bottom end at all. I done a custom grind hyd roller with comp xfi lobes 230/236 on a 108 lsa and 570ish lift. Went with dart 180 iron eagle heads with comp 26918 beehive springs. Intake was an airgap performer rpm with a 750 street hp holley. The combo was good for 457 hp at 6600 rpm and 436 lb ft of torque at 4400 rpm. I really dont think a 350 needs much more than 180 cc's of intake runner. Ive done several 350s with 180 heads that were very capable of 7000 rpm. Oh and that combo was only a little over 10:1 and i run the quench just as tight as i can get away with. I think this one was around .028 quench. I have ran them as tight as .022.

riplt1

When you say .028 quench, are you talking about the gasket thickness or the quench area in the combustion chambers?

FIRECHICKEN5.3

I set of aluminum L98/zz4 heads will make that power level. 58cc combustion chamber. I recommend a lunati cam.

big hammer

if you're looking at an entire new rotating assembly, might as well go 383 with some 210-215 cc heads and make some really good hp. don't have to rely on compression as much either.

riplt1

Is 450 hp that easy to make with a 355? Could you make that without any head work?

I-H8-RICE

http://www.hotrod.com/projectbuild/h...k_chevy_build/

can be done for less that 5k especially because you have a starter already.. 450 hp on pump gas is really not all that difficult.

actually i belive I am pretty close to 430 on my 332 with patriot performance 185cc 2.02 10.35:1 running 93 on an XS282 comp solid flattappet cam, if you go with AFRS and a roller cam with more cubes you could easily see 500