Ls1nyetrus

I bought the t rex cam for my ls1 99 trans am wondering what heads would be the best bang for my buck keeping in mind the piston valve clearance ... I have a th400 3500 3800 stall 3.73 gears ... and also should I go fast intake or victor jr with nitrous ???? thanks ... I want to run 10s street car

A.R. Shale Targa

iTrader: (2)

TRICK FLOW 205s
stock valve sizes (unshrouded)
near 300 CFM of flow from a 205cc runner
high velocity intake ports help the gigantic donkey dick cam
small combustion chambers to crank the compression ratio up to 11.5:1
13.5 degree valve angle helps with PTV clearance issues from said cam
and they have powdered metal valve guides to be stock rocker arm friendly

JakeFusion

iTrader: (7)

Where the hell did you find a T-Rex. Thunder has been out of business for like 4 years. So that's either just a 242/248 XE-R cam (same thing) or it's used and several years old?

As for heads... depends on the intake you decide to run. If it's the Victor Jr., I'd probably go with some TFS 220s or PRC 227s or something with enough cross-sectional area to feed 6500+ RPM. The cam would actually work well with a single plane given the overlap. I assume a 3.9" bore? If 4" bore, more heads become available to you.

Ls1nyetrus

Ws6store.com has it

JakeFusion

iTrader: (7)

Well damn.

I also forgot, PRC has the as-cast 225 heads. I think either those or the TFS heads from Brian Tooley are insanely good heads for the cash and would match up well with the T-Rex.

Ls1nyetrus

What stall should I use for with my turbo 400 to keep it street car? What intake manifold is best victor jr with a 4150 throttle body or fast intake?

JakeFusion

iTrader: (7)

Depends on what you want to do. TH400 doesn't sound like the most streetable combo without overdrive. So I'd do a 4500 stall.

And if you want to run the RPMs up top, I'd do a Victor Jr. But the FAST doesn't really lose anything until past 6500. But the T-Rex with the right valvetrain can turn 7200.

Ls1nyetrus

so t-rT-Rex cam victor jr intake 4150 tb heads nitrous th400 4500 stall 373 gears and full bolts ons would it be a street car? Any idea on wat ET at the track would it run with the 150 shot?

JakeFusion

iTrader: (7)

If nitrous, I'd back off the 4500 and get a nitrous friendly 4000 stall.

ET depends on weight and conditions. TFS 220s, T-Rex, Nitrous 4000 Stall, 3.73s... 7200 redline. 3400 race weight. Low 10s I would think.

Ls1nyetrus

what else would I need? I got a 170k miles motor would it need rebuild or do it like it is?

JakeFusion

iTrader: (7)

Spray it until it explodes.

It can take a 200 shot. Just tune it by reading the plugs. The nitrous itself won't kill it. The RPM and detonation will... So I wouldn't spray at 6800+ maybe have it come on with a 50 shot out of the hole, the progressive 150 at 5000 and kill it at 6500 but spin to 7k. See how that works.

Another option is rod bolts. But if you do those, you might as well freshen up the motor and have the rods honed for the bolts. But if you go that far, the Scat I-Beams are cheap ~ $300 whereas the bolts are anywhere from $120-200 + machine labor costs. So the Scat I-Beams would be stronger than a Gen III rod.

This becomes a rabbit hole. You can **** money away forever.

hfthe3rd

iTrader: (1)

I would love to find a old trex cam laying around!

kinglt-1

iTrader: (26)

I would not even mess with a Trex...buy something with smoother lobes for a street car. The valve train will thank you!!

http://store.cammotion.com/junkyard-...plane-camshaft

imma_stocker

iTrader: (19)

With ported (crappy job) 241s mine put down 415/383 through T56 and 3.73 on stock height tires. Lopey as hell and good on the bottle.

Powerband was effectively 3000-6500.

Jake99

iTrader: (2)

If all you want is 10s with nitrous just do a stock ls6 intake with a stock 243 head and spray a 150-175 on it, would work pretty good with that cam. Then a yank ss4k converter. The hardest thing to wrap someones mind around is how to ballance air velocity and air flow, both are equally important. If you want to spend a little and make a little more power then get a head with the smallest runner that will flow to make the power you want. 300 cfm can make 600hp, so a afr or trick flow 205 would work real good, and run a fast 102 with it.

JakeFusion

iTrader: (7)

TFS 205 is a good suggestion too. It's a fully CNC'd head for a little more than the 220s. And a small 58cc chamber. You need compression with a T-Rex. But any other head and milling with the T-Rex = flycutting the pistons. I wouldn't do that and then spray 150.

I believe you still have stock or better than stock PtV with the TFS 205s at 58cc.

CAMMOTION PERF

Hey Ls1nyetrus,

I would like to offer your some options and a few things to consider:

First, for a stock short block LS1 in a relatively heavy street car, I think you will find that your performance will be better with a Fast or Atomic Airforce style intake manifold unless you are planning on spinning to 7500 RPM or better.

In addition, make sure you communicate clearly with your stall converter manufacturer on how much nitrous you will run. 9"-10" stall converters in the 3500 RPM area tend to be a good choice for guys who want both good performance naturally aspirated as well as a small to moderate shot of nitrous (100-250 hp). Many of the looser stalls converters built for optimal naturally aspirated engines start to slip and become inefficient on nitrous oxide.

As for a good camshaft for your application, I will give you a recommendation for a couple camshafts that would be excellent choices for your performance goals:

If you do decide to go with the Victor Jr style intake, this camshaft will work great with a 3500-4000 converter and handle up to a 250 shot of nitrous:
http://store.cammotion.com/junkyard-...plane-camshaft

If you decide to retain the stock intake or go with a Fast or Airforce style intake, then this camshaft is an excellent choice for a 3500-4000 converter and up to a 250 shot of nitrous:
http://store.cammotion.com/titan-king-cathedral-port

Both of these have a heavy lope at idle and are designed for serious street strip performance. They will both have acceptable piston-to-valve clearance in a stock LS1 with stock thickness head gasket if the heads have not been milled more than .010".

Let me know if you have any questions,
~Steven

Ls1nyetrus

I had a T rex cam in mind and heads

CAMMOTION PERF

I hate selling a camshaft the size of the T Rex with stock 15 degree heads because of the crazy tight valve clearance. I nice solution we have used for other customers are the MAST cylinder heads. They have a 12 degree valve angle and can sport as much as .100" more piston-to-valve clearance than a stock head. With that, I could make a cam that was more of a T Rex size, but I would change the valve events a bit to fit your combo better.

~Steven

Ls1nyetrus

I'm aiming for a 10s car