Originally Posted by narcszm

well if they're balanced with a SBC an iron-block, aluminum-head LSx should do you fine. Especially if you build a nice low-compression 408 for forced induction. The recommendation of the LS2 was a good one. If you want to spin the motor high, get a larger bore and a de-stroked crank and you should be able to hit 9Krpm without trouble.

Originally Posted by Builder

Thank you for the replies...

SSactionLS1 and cyphur_traq, I was hoping that I might be able to build it myself. However, purchasing a short block is not out of the question. If I go that route, I will definitely consider one of the sponsors.

Z1500, that's what I am talking about. The method you outlined sounds like a good plan. As I am being careful with weight, is the iron block the best option? I mean, can the same approach be used with the LSx aluminum block? The AEM product looks like a great ECU. I have read about the FAST and Commander products. I will have to read up on the AEM now, too. Good lord! The stock crank can handle 750-1000 rwhp? That's huge! Going stock there will also save some $$$. Although, if those numbers are at the upper limit of the stock unit, the savings isn't worth the cost of a rebuild. Are you confident that the stock crank can handle that kind of power? That's the biggest problem...the transaxle. Although, the car only weighs about 2,300 lbs with me in it. So the tires break free before the torque gets to the ground. This car will be used mostly for road racing and a little 1/4 mile. Planning on two transaxles; one for a top speed of 180 and one for about 230 mph. Above 160 mph is where the power and torque will be most important.

flippincamaro, yes it would!!! I can hardly wait to get it on the road...

goober35, that's what I need to do...reverse the intake by turning the manifold. Is there anything special needed to flip it around? I have heard that the oil pressure sensor needs to be 90'd, or something like that. And some wire lengths probably need to be shorter/longer. Also, I would be interested in the details of your build..the specs of the "forged this and that". So, the stock (ported) heads will work if I use low-compression (turbo) pistons. No real need for the LQ4 heads. The 8k peak is not manditory. The stock gearing on the transaxle can be changed to fit the rev/torque curve. 7200-7400 works, too. Holy crap, you were up late. Hope you were partying like a rock-star!

Thank you for the replies. This is a great forum. The GTR is designed for a Gen-I block, but the LSx is the way to go and this forum has me jazzed about building one.

Originally Posted by y2khawk

The LS2 is basically an aluminum version of the 6.0L iron truck block. Retains the same bearing bores as it's Gen3 brothers, but has a 4" bore The knock sensor location and type has changed, along w/ the location of the cam sensor. This poses a couple wiring and tuning changes, but nothing to major.

the block and crank strength are really not an issue. I'm running both stock pieces at probably double the power level your after. Spinning it beyond 8k will be the task at hand. How long do you plan to have it there? Sustained high speeds will need serious valvetrain parts to live. Short blasts and you can get away with alot.

I personally am awaiting Factory Five to release the GTM, their equivelent to the GTR. Mid engine designed around the LS1 and C5 running gear w/ Porsche transaxle. I've already got the twin setup in my head for it Yes, it's an addiction

Originally Posted by CAT3

I think SDC has new blocks for $995! You really need to go to the "for sale" section for a block and crank there. You should be able to get one cheap there. Even with a new cast, have a competent machine shop check it and do the machine work. Even new, they dont use a torque plate when finishing the blocks at factory so soon after you could run into some issues later. You can use the stock crank, lots do, but I am sure your not interested in rebuilding yearly, and most that do use the stock crank at those levels are doing that for 9 sec or less at a time. For a RR application I would take the safety step and go forged, Lunati, Crower etc. Block $600, rotating assembly $2200 no bad for a bullet bottom. I would either use some AFR heads, or nice quality ported heads and NOT use the GMPP ASA heads. Theres plenty of little stuff, Oil pump, front and rear covers, oil pan, valley cover, etc that you should be able to pick up either thru SDC or in the for sale section to finish it off. Using FI stock ci, you should be able to build the engine with FI under $20k, then need things like the fuel system to support it. Not to many warranties are available, non I know of for FI at that. I agree 26k is a lot, especially if you are not getting exactly what you want.

Good luck,

Charlie

Originally Posted by marco427

I'm familiar with the Ultima, and agree that a strong LS1 would be a great fit with this lightweight car. I do have one suggestion that you may want to consider before going totally gonzo on a forced induction motor. I'm running a 530 RWHP 427 (C5R block) in a '98 Vette, and at 3400 pounds with driver, it's damn near unmanageable on the street. Even with significant upgrades to the suspension, wheels and tires, and brakes, I would say that the last thing that I need is an additional 200 HP. I cannot imagine what my engine would be like in a car that weighs over 1000 pounds less.

Obviously, I know nothing about your driving skills or experience in ultra high performance cars, but unless you hold at least an SCCA National license and have won more than a few track events, you may want to walk before you run.

Originally Posted by narcszm

he probably meant http://www.sdpc2000.com/

Originally Posted by y2khawk

The LS2 is basically an aluminum version of the 6.0L iron truck block. Retains the same bearing bores as it's Gen3 brothers, but has a 4" bore The knock sensor location and type has changed, along w/ the location of the cam sensor. This poses a couple wiring and tuning changes, but nothing to major.

the block and crank strength are really not an issue. I'm running both stock pieces at probably double the power level your after. Spinning it beyond 8k will be the task at hand. How long do you plan to have it there? Sustained high speeds will need serious valvetrain parts to live. Short blasts and you can get away with alot.

I personally am awaiting Factory Five to release the GTM, their equivelent to the GTR. Mid engine designed around the LS1 and C5 running gear w/ Porsche transaxle. I've already got the twin setup in my head for it Yes, it's an addiction

Originally Posted by strokedls1

I've been loking at that same car for about a year. Was waiting to see what the finished product looked like first, but the tube chasis was real nice. I will probably just do a ls2 stroker on that though.