bubba11193

going to be buying a c5 corvette here within the next year and going to be going some mods to it. but want to get the most horsepower out of it as i can but keeping it n/a. Wanting to do afr heads and the reverse split cam by thunderracing, what the best head that i can get that will give me the most benefit out of it. going to be doing full intake and exhaust also on it, so their will be supportngs mods for it.

0HorsePowerAddicts

The trickflow 215 cnc heads would be my choice for an ls1 out of the box. They are well proven to perform. The reverse split from thunder is not the cam to go with if you want to make the most power from a ls1 NA.
Where are you located?

0Jon@Texas-Speed

Take a look at the PRC 215cc heads. They are an aftermarket casting that will perform as well or better than most of your big name cylinder heads on the market today. The heads are factory rocker friendly and come with a .650" lift spring out of the box! Check out our website for more info. and flow numbers on these heads as well as others in the PRC cylinder head line up! Be sure to let me know if you have ANY questions!

Jon

bubba11193

well im wanting it to have a nice deep lope to it and keep it as an everyday car also and making 550rwhp when everything is done

civlant

Hopefully you're going with more cubes or FI to hit 550RWHP. For the stock shortblock I would recommend either AFR 205s or Trickflow 215s. Only problem with the 215s is having to buy aftermarket rockers but they definitely perform.

tblu92

I agree that keeping the intake port size in the 205 -215 range is the best choice---Getting runners above that is usually only good for BIGGER cubes or engines running above 7000 often---If the port are too big it will make the car very lazy downstairs--
550 RWHP seems to be a stretch---It can be achieved N/A but as i say only way up in the 7000-8000 range or with more Cubes---so if this a DD car or not a decicated racer--You would get more usuable TQ and HP by going to something in you Cube and RPM goals---
From what i read the new MAST heads are a great choice---They are the 1st ones I've sen that can be used on a small bore LS1 ---And they are the newer L92 style and have to use the newer L92 manifold
These heads flow HUGE #'s !!! well over 300 CFM down as low as.450 lift--- but again---to get the best performance from them you need more cubes and to run it zbove 7k

bubba11193

well i will be building a 403 stroker after it also and will either be twin turboing it or supercharging it and then dropping it in place of that and having it as a fun weekend car then

bubba11193

but for now i want to get as many ponies out of it that i can but also keep it stock cubes and have nice lope to it also. dont want to turbo it or supercharge it for now and im a bigger fan of just hearing the pure engine power coming out of it.

ALVETTE00

550rwhp

not from a 346/LS1 NA !!!

Y2Kvert4me

It's been done before, just won't be cheap or very street-friendly.

And certainly not with shelf-issue AFR heads and/or a reverse-split cam.

bubba11193

my friend did it with his 02 zo6 made 561rwhp na and with afr heads but i dont like his cam. His is custom grind. I want a cam that makes alot of power but has the lope of a reverse split

Y2Kvert4me

Id love to see the graph of that one.

550 n/a out of a 346 will usually mean solid roller, sheetmetal or ITB intake, BIG runner heads and a 250+ duration cam.

Not your ordinary street car combo by any means.

slowtealz28

You're most likely, and almost guranteed not going to make 550 at the wheels with stock cubes. Maybe engine hp, but not hp at the rear wheels. Some guys have made over 500rwhp with stock cubes, and some guys with strokers have made just over 500rwhp. It all depends on how much money you have, your goals, and willingness to go with a "wild" cam.

If money isn't an option get trickflow heads. If money is tighter than go with something like prc heads. If you plan on supercharging the car or turbocharging it then stay away from 5.3L heads and don't mill your heads at all. As for the cam, reverse split cams aren't too popular because they sacrifice a lot of top end power. There are traditional split cams that make a TON of lope. Look at cams such as MS4, MS4, G5X2, G5X3, vindicator, polluter, whiplash, etc.

bubba11193

his z06 isnt his everyday car, its his weekend car that he also takes to the drags, he kept stock cubes but just modded everything else to the extreme

0331MARINE

Maybe that was flywheel HP. We need a graph on this one. I would have bought AFR's along time ago. Also if this was true there would be alot more people doing that VS paying 5k to go FI. Pics of his motor?

bubba11193

ya but my buddies and i would rather have it pure engine power and no fi, i try to stay away from turbos and superchargers never been a big fan of them

0331MARINE

Im just trying to find out how your friend made 550wheel on a stock ci LS6. Do you have pic of his motor? What kind of intake manifold is he using?

slowtealz28

You're confusing me and kinda contradicting yourself. What do you really want to do with the car, realistically?

AU N EGL

May not be too street friendly.

I have driven a few 550 rwhp 346ci LS6s. Definitely not street friendly, nor passed emission and needed engine rebuilds frequently.

They both ran Fast 92/92 combos,
LPE Speed World GT 243 heads. 59.5
GM Cup Cam 239/251 570/570 106
Dry sump systems
7200 rpm red line

110 leaded race fuel

These were all out race engines. Not cheep to build ( ~ $15K each) nor lasted long. But they went like a bat out of hell.


an LS2 402 / 403 or an LS3 418 may be a more reliable build for that kind of power.

Good Luck

01_torch_red_vette

I agree 550 is not a realistic goal for N/A 346. Not saying its impossible, but it would take alot. I was able to get 475 to the wheels, but that was with the heads milled and ported by tony, fast 90 ported by tony, ls2 throttle body ported by tony, and plenty of other supporting mods. I could have went with a bigger cam, but I wanted more manners and power throughout the the curve rather than a big peak hp number.