Hey guys, Those of you that have spent a lot of time with the Holley Stealth ram and tuning it. On a 355 with stock HSR with 280 CFM alum heads at 550 lift and 9.7 comp, what duration @ 50 will yield around 400-430 FWHP and have good street manners. I know different intakes like different profiles but I need to know what a HSR likes so I can dial this in. I was thinking an LT-4 hot cam or a xfi 268 but I am sure a custom grind with specific duration that a HSR likes will get more of its potential. Would like it to go to 6000rpm. Nothing real fancy since it is for a street driveable daily driven vert but I would like to maximize what I have instead of going generic and leaving 30 or so horsepower and torque on the table. Thanks in advance.

 

I think with a 355 and without knowing much else about those heads you will need more duration than a LT4 hot-cam provides to break 400rwhp. I think you are a little short on compression though. I'd do the math to figure out your dynamic compression. I think the Wallace Racing site has a decent calculator. You might have to look up some stuff though.

This is the cam I have in someone elses car pretty much.
http://www.youtube.com/watch?v=YUXFpsYvk2w

The LE cam I have has more lift, its .578"/.574" with 1.6 rockers, the one in the video is .555/.555".


*Edit: I just realised you were looking more at a crank HP number estimate. Yes, the LT4 hot-cam should be able to reach those numbers at the crank with a decent set of heads assuming you have the supporting mods and a good tune.

 

It has great exhaust 2210s and 4 inch back, 52mm throttle body, I can get some ported bowties that flow about 280 at 550 lift and will give me about 9.7 comp but I can run a thin gasket and get close to an even 10.0 to 1. I was thinking someone has figured out that the HSR likes a specific duration spread like a straight up cam @ 224-224 or I read somewhere that a tuner went 222-236 and the motor responded well. The car has a 327 9 bolt posi and a be cool radiator and is set-up well with a new 700r4 with 5 pinion planets and all the goodies waiting for the new motor. I just need to find what flow heads with what cam will make 400 plus and be driver friendly. People with good combos need to chime in so we can all compare. The HSR seems to be easily one the best all around intakes and probably the most affordable and I already have one but it is a solid roller motor and I didn't really learn much from that build since it was not a daily driver build. I would even use the stock tpi if someone knows a good combo that would meet my needs. Just need 400 plus flywheel power and I have an all forged 355 with slightly dished pistons and a HSR with 30lb injectors and Kirban reg. Great exhaust, cooling and rear.

 

I do custom grinds, I'd probably do something around a 226/234 but with 2 different style lobes. Email me if you're interested, I have plenty of references.

Thanks and good luck.
Mark
fastone01@hotmail.com

 

Awesome, I have some cams I could send you if you re-grind them. Give me some info on a few you have in mind and the idle quality and what I will need head wise and compression wise. My e-mail is allen.bray64@yahoo.com