My brain is about to explode from all the research I've done, but I still have a couple unanswered questions.

I'm going to be doing a H/C/I swap on an '01 LS1. I've got a set of stock 243s, a FAST 90/PTM 90mm TB, and I plan on having Patrick G spec a cam. I've decided to send the 243s to TEA for porting. I would like to get ~450rwhp and at least 400rwtq from the whole setup, but the catch is I want the cam to be stealthy. I want it to have a near-stock idle. I'm not dead set on the 450rwhp number - if it's 10-15 HP less, I'll be happy.

That being said, setting up the 243s correctly will play a big role in achieving my goals, correct? I'll be keeping the stock valves, for better valvetrain stability. How much should the heads be milled, if at all? Should I just go with a thinner head gasket? What else can I do to "optimize" a set of 243s?

FYI, here are my supporting mods:

SLP lid/smooth bellows, SLP CAI
Pacesetter LTs, ORY, Borlamouth

I'll be getting an underdrive pulley and possibly an electric water pump, as well.

 

Fly cut and run the highest compression you can. Basicly free power.

 

Whoever is grinding the cam will be able to tell you how much to mill. Well, if you don't want to fly cut that is. Then again, there is always this option: https://ls1tech.com/forums/dynamomet...k-results.html

If you are already putting down the numbers in your sig, then I think you will be pretty close to your goals. That isnt bad at all for just some bolt ons.

 

I would prefer to avoid flycutting, if possible.

One more question - I know flow #'s aren't everything when it comes to cylinder heads, but TEA's exhaust flow #'s are way ahead of other comparable companies' heads (meaning "Stage 1" or similar heads). Will this translate to a significant advantage, assuming the combustion chambers and runners are equal to a comparable cylinder head with less exhaust flow?

 

No need to flycut unless you want to go with a super huge cam with milled heads. Just port your heads and get some Patriot gold dual .650 springs. Patrick G should spec out a cam to reach your goals pretty well. Get that FAST ported, and get an underdrive pulley if you really want to make sure you'll reach your goals. Make sure to upgrade your oil pump, and wouldn't hurt to get an ls2 timing chain while you're at it. A bigger lid (FTP 104mm lid) and a 100mm MAF would probably push you over 450 depending on cam specs. But all that will probably be maxing out your stock injectors/fuel pump if you haven't already upgraded. Some 42# and a walbro 255 would do it.

 

So I should ask Patrick G then.

The FAST is already ported, by AFR. I was looking at the ported LS6 oil pump and LS2 timing chain kit from TSP. I should also get better lifters and pushrods, right?

 

I would say this take you heads to a reputable shop TEA, AI etc and give them the cam sheet and have them do the head work. That will optimize the cam potential. I am running a custom cam from Ed Curtis and Advanced Induction work with him pretty close so I had them do my heads. I had 243 stage 1 done with LS6 valves and 921 springs and the cam is fairly stout, so I would do research and see where ever your cam is coming from and who do they work closely for heads and have them do it.

Before I forget I don't mind fly cutting but to me is fo last resort. If you can find a cam lets say smaller that gives you close performance to a bigger cam and it will take that option away then I'd go with the said cam.

 

Yes, the better exhaust flow will help you because every one and their mom has off the shelf cams without enough exhaust duration, except Geoff @ Engine Power Systems. He taught Pat G all about cams anyways.

 

I'm going to be installing a very similar setup on my car soon pat g told me wat to mill my heads to based on the cam

 

My problem is that I need the head flow data and combustion chamber size for Patrick G's cam spec request form. I guess that's no longer a problem though.

 

Just tell him what you want to do, or take his advice. I would ask him about anything you have a question on. Tell him you don't know. You can base a cam off your heads and vise versa.

 

Don't limit yourself to stock valves. Most LS1 motors can handle 2.02 intakes and 1.575 exhausts. That really helps flow if you open it up with bigger valves. To have a shot at your goal of 450 HP, you're gonna have a noticeable idle lope. By getting a high LSA like 114-116 you'll be able to smooth out the idle a bit along with bumping up the idle rpm a little.

 

From what I understand, the small bore of the LS1 limits the effectiveness of larger valves. They're only worth a couple more CFM, plus they weigh more, putting more strain on the valvetrain especially as RPMs increase. I'd prefer to keep the stock valves for durability. Besides, I've seen quite a few people have impressive results with the stock valves.