Elysian

What size cam is usually required to hit 400rwhp in an LT1/LT4? I have a H/C swap coming up and want to hit 400 minimum on a stock shortblock. Anyone have dyno-graphs? Any input would be appreciated.

kevinb

The heads will make the most difference. I know a few lt1's with TEA heads (a sponsor) and i think an off the shelf comp xe camshaft making the 400hp mark.

disco192

Get some AFR heads, a custom cam, tuned, and boltons.

Or if you want a street beast, im thinkin about goin turbo. It sounds kinda ricer, but it will make a rediculious amount of power. Ive heard of alot of people with bone stock 5.0's runnin 9 lbs put down 450 to the wheels (obviously tuned and fuel system upgraded to handle the power).

I just wanna see what a LT1 do under turbo boost. I know it would be amazing. http://66.70.20.245/store/scripts/pr...p?idproduct=11

Elysian

About what size, though? Comp XE 224/230 or bigger? I see LS1 guys hitting 400rwhp with a TR224 cam. With decent heads, duration on a cam should be about the same for the same power??? PS: I'm not interested in going forced induction or with NOS. Just NA.

Fastbird93

iTrader: (10)

Almost definitely not with the 224/230 unless you've got some secret heads. The 230/236 will do it with GOOD heads. No need for AFR's or the like, stock ported LT1 castings will be fine.

Cams that for sure will make it: 230/236 XE, CC306, GM 847 (I REALLY like that one) immediately come to mind.

I'm trying to get there on my 224/230. Joe Prince did a killer job on my heads, but I'm working some kinks out of the car. The part that I'm waiting to put on is the 1.7 rockers. That will give me the lift to get the valve transition into the meat of the flow, right at the peak. I may, I may not. I could still put an ORP on the car since I'm running a cat, and there's a couple of other tricks up my sleeve still. We'll see. With a perfect tune I think it may be possible, but it's not the norm on a 224/230 cam.

Elysian

With a Comp 230/236 XE will I need to fly-cut pistons? Will 230/236 hit 400rwhp with 1.5 rockers or 1.6? What are the specs on the GM 847 cam - I've never heard of that one before . . . ?

Fastbird93

iTrader: (10)

No, the off the shelf 230/236 needs no bottom end mods. It's only a .544/.555 lift with a 1.6. And yes, you'll need the 1.6 rockers to hit the 400 with that. I'm not a big fan of that cam because you tend to sacrifice some overall torque.

The GM 847 is actually a crane grind: 234/242 @ 0.50, .575/.595 with a 1.6 rocker, 112* LSA, I forget what the intake centerline is. To put it in perspective, a guy on CZ28.com made 357 SAE RWHP with this cam on STOCK heads. There's more than a few running over 400 RWHP on marginally ported heads (260ish @ .550).

Elysian

So if I went with the GM 847 cam would I need to fly-cut pistons? How high with that cam rev? I would like to be shifting before 7000rpm - want my bottom end to last a little while. How is it that the GM 847 cam would have more torque than the Comp 230/236 cam?

Fahad

440 rwhp LT1 stock bottom end LT1 with a home ported set of stock heads, and cam it's from TR [ThundeRracing] you can ask Paul from TR about the car.

I hope this will help you..
https://ls1tech.com/forums/showthrea...highlight=rwhp

Good luck..

Elysian

440rwhp sounds awesome. It WOULD be a good thread . . . but how big is the cam!!?? Everyone keeps saying "bigger than this" or "smaller than that," . . . such bullshit. I wish they'd quit f'n around and spit out some specs. It's not like I'm gonna come find the car they built and race him. I'm building a street car. Not that I doubt Thunder Racing. If they say 440rwhp, that's what it was.

What is the general consensus on the 233/239 Combination Motorsports cam? Anyone running it making over 400rwhp?

*High-Noon*

Easy way.........get some AFRs! I'm right there.......

Elysian

I have AFR's. 195cc LT4's fully ported. I'm waiting to put them on. I want to pick the cam correctly so I'm making AT LEAST 400rwhp.

Fastbird93

iTrader: (10)

That's SAR2K's car I believe. I've caught wind of one psuedo spec on the cam. Durations are 240ish at .050. That's a BIG HIGH revving cam. Definitely NOT the norm. Same kind of results are happening with a couple of other guys with good heads and a completely custom grind. Joe Overton comes to mind.

95 Formula

iTrader: (2)

Yep..thats SAR2K. I wouldn't call that cam a daily driver type of cam. Weekend toy..yep. He actually made a tad over 450 with more tuning. When he gets this sucka dialed in its gonna be a 10 sec. stock bottom end NA car.

quest for 400 rwhp...The power is in the heads.

Fastbird93

iTrader: (10)

Agreed. To a point. A well matched head and cam setup is the key. You can have a killer set of heads, but put a cam in there that just doesn't utilize the characteristics of the heads, and get nowhere. That said,

I want a custom grind.

Elysian

I'm curious if anyone knows how drivable that 440rwhp LT1 is? I've seen that 450rwhp car as well (97 Trans Am WS6 I believe). I'm interested in a daily driver that can cruise reasonably comfortably up and down the road at ~1800-2000 rpm. I'm sure I could make 500rwhp if I put a 280 @ .5 cam in, but I don't really feel like getting kicked in the back every time the crank turns over. So obviously, I'm willing to make some trade-offs. If I can make 400 rwhp I'll be happy. More would obviously be acceptable, assuming these criteria: drivable @ 2000rpm, NA & running on pump gas.

Elysian

Does anyone know what the maximum lift can be run on 195cc AFR LT4 heads without having to fly-cut pistons?

Fastbird93

iTrader: (10)

If the AFR is the same "height" as the LT1 casting, you should be good to about .600. I'm not sure about the AFR casting though, but hopefully that will help to give you a starting point.

Elysian

The AFR casting using the same hardware as an LT1 (rockers, same lenght pushrods, springs, etc). The heads I've got have 56cc chambers (which is smaller than LT1's, I believe). I don't know to what extent that affects how much lift can be run . . . ?

trax

iTrader: (2)

Ultradyne (back when it was still around) had a cam that was 230/238 .565"/.565" 112 LSA.

With good bolt-ons and strong heads, that cam will break 400 easily. NickS on FRRAX.com hit 411 rwhp with it.

But again, just because you toss a cam in doesn't mean anything if the supporting mods aren't there. Don't forget injectors either. My stock ones are pretty much maxed out on my 224/230 (thus my peak rwhp of 366). Once I bump up to 30 pounders I should be at fastbird93's power levels