Builder

Hi Folks,

This is my first post. I have been reading this forum all day and there's tons of great info. Here's what I would like to do...

There is a "kit car" called an Ultima GTR that I am planning on building. It can be viewed at http://www.ultimasports.co.uk/gtr The car weighs around 2100 lbs. wet. The factory supplies almost everything except the engine. I would like to build an LS1 for this kit, so it's a clean slate.

From what is posted here, a boosted 346 LS1 should have little trouble making 750 shaft horsepower on pump gas. If it can be done N/A, that would be best. However, the GTR has just enough room for an intercooled turbo installation if required.

Questions:

1) I know, this is a big one... Given the target of 750 sHP and 7500-8000 peak revs, what components would be required to make it bullet-proof? What stock parts can be kept? Not many, I suspect. 700 lbs/hour pump, 70 lbs/hr injectors, 1000 CFM.

2) Can the F-body computer (OBD-2?) be used to control fuel injection in an installation that only has engine sensors like MAF, MAP, IAT, CPS, and O2 (or is something else required, like the Delco ASA computer)?

3) Best process: How would someone go about this? A new, crated, LS1 can be purchased from a GM dealer like Sallee and torn down - the stock parts sold. Or, a raw block can also be purchased new. The "used" market is a possibility, too.

4) If turbo is the best route, it appears the '01+ LQ4 (aluminum) heads are a direct fit and a good option for porting and lowering the C/R. Or, would an aftermarket head like Patriot or AFR be a better route?

Also, the intake must be rotated 180 degrees. It will be mated to a G50 Porsche Transaxle.

I know these are huge questions and the answers are many. I appreciate your feedback.

SSactionLs1

I would have one of our sponsors build you a large diplacement forged engine designed to handle boost unlike the stock ls1. Its also cheaper than buying a new ls1 and having it modified.

Z1500

I'm doing something like that in a C5.
Start with the cast iron 6.0L block, toss in a stock LS1 crank, good forged pistons+rods. Then some nice build high RPM heads.
Screw stock ECU and go AEM EMS
Pc. the engine together starting with a new 6.0L block from GM
The forged pistons will take the CR down to 8-8.5 so head CC doesn't matter much.
Turbo is the only way to fly and this set up should do 750whp on pump gas all day and all night. It should do 1000+ no problem but good luck making the drive trail take it.

Kevin

flippincamaro

iTrader: (23)

would be very nice to do

cyphur

iTrader: (10)

Get a sponser to build you a good motor. Allan @ FMS, Sean @ Fastech, Paul @ Thunder, MTI, HPE, et cetera. Look to the right and give them a call --->

goober35

iTrader: (1)

Y rought the intake 180 degrees when you can put the intake on backwards and do it that way.

You can use a stock PCM if you want. The reve limiter on the stock pcm is 8000 or that is what it can take. Also you will have to do something with the maf. If you flow as much are as i plan to witch it looks like u are doing the same the stock maf might handle it. It is a hit or miss thing.


I am building a short block for under 2k. I am using the stock crank ,block and main caps and that is about it. I have all new ARP bolts and forged this and that.


There is only one comany making ls1/6 heads and that is AFR everone else just ports ls1 casting heads.

An 8k peak reve is a high order. It can be done but it will take some bad as parts and a good mechine shop to balance it. I will spin mine to 7200-7400 depending on where the power peaks. Its all in the cam.


Sorry for the spelling it is almost 4 right now so my brain is not working right, right now.

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.

family sedan

iTrader: (3)

A iron block would really mess up the weight distribution on the GTR. Definitely stick with aluminum. The newest thing will be to have a LS2 block. Look around for Car Crafts article on the GTR with a LS1 in it. He had H/C and a hidden 100 shot.

Builder

The weight distribution is already about 60/40 back to front. Going heavy on the block wouldn't make it any better (mid-engine mount). Iron block and heads adds 140 lbs., so I would like to stay aluminum, if I can make the power I am looking for with aluminum. It sounds very do-able ... from everything on this forum. The time slips I see up here indicate much greater performance than what I am looking for.

I had the opportunity to meet Jeff and go for a ride in his GTR (Car Crafts article) a couple of weeks ago. What a great experience. I spent the weekend with 10 owner/builders and some future builders like myself.

Sharpe

iTrader: (7)

EBay has all kinds of complete LS1s with computer, sensors, transmission and everything for under $5000. Here's the first I came along: http://cgi.ebay.com/ebaymotors/ws/eB...937484062&rd=1

MTI can re-sleeve (http://www.darton-international.com/main_fr.htm) an LS1 and make it capable of accepting over a 4" bore. A lot of people on here are running 427s making 600 horsepower or more. There are even people getting 454 and 455 cubic inch displacements out of LS1 blocks. Won't 600 horsepower get you well into the 10s anyway?
http://www.motorsporttech.com/

family sedan

iTrader: (3)

Awesome. Jeff seems like a really intelligent guy. He won the real steet eliminator the previous year with a boat of a Cadillac. He arrived this year and they wouldn't even let him compete with the GTR because he would of blown everyone away easily.

Definitely go aluminum, you won't break it. If you want to be really unique build the LS2 block.

family sedan

iTrader: (3)

BTW a crated "street rod" package LS1 is like $4500 from GM. It includes all wiring and sensors, the motor, etc. All brand new, never used, and comes with all the instructions and everything you need.

Sharpe

iTrader: (7)

I think its more like $6000.
http://www.sdpc2000.com/catalog/120/...e-Assembly.htm

Builder

Sharpe, thanks for the links. I put that block and trans on my "watch" list. It's possible that a descent LS1 block can be had for around $1k. I think a new, bare block is about $1,400 from GM. Actually, I might consider the combo above; the T56 will fit in my '96 Impala with the LT1. Or, I could sell it separately.

Yes, by my estimates, at 2,300 lbs., 450rwhp will get me into the 10s. However, that's not the goal. Considering about 18% loss in the drive train, 740 sHP yields about 600 rwHP. That should put the car into the 9s. The goal though is open road racing and the Silver State Classic. One trans will be used for "daily driving" and the track; the other for the high top speeds of up to 230 mph. That's the goal and the HP required.

The MotorSport Tec site indicates I could start with their aluminum (very) short block for around $4k (I don't have an exchange). That's not bad. That Darton stuff is very cool too.

Phoenix 5.7

iTrader: (7)

is price a real issue? for a bulletproof engine, a C5R 7L block is the top of the line, but its like 6000 for just the block. MTI has an all bore 387 that could probably be built for turbo and reach ur 700 to 750 goal.

Builder

Yes, that was a great weekend. I still smile when I think of the G-Force and the quick throttle blips to over 130 mph three time in just a couple of blocks. And, folks on the road couldn't figure it out...what kind of Ferrari was that?

The LS1 kit from GMPP (#25534322) is a complete package for around $6k and tough to beat. However, I think for my build, since I will be using forged "turbo" pistons and rods, I would be better off starting with a new GM bare LS1 block (#12561166) for around $1,400. I might be able to pick up a stock crank for $300? GM LS6 heads (#12560801) are about $1,400. Or, the GM ported(!) ASA racing heads (#25534321) milled, with high-lift valves are around $2400. Pistons, rings and rods for $2k? It all adds up pretty quick, doesn't it? And I haven't even thought about the turbo yet!

Thanks for the input! Any more suggestions, I am all ears...

Builder

Phoenix57, well...it's not really a price issue. The C5-R block would be a great option. I think it's probably the proverbial "shotgun to kill a fly". Yes, it's bullet-proof. But $6,400 for just the block? That's a little rich. I am sure it has it's place, though.

narcszm

why not find out who built the motor for the TT GTR that holds the world 0-100-0 record and say, "gimme one of those."

family sedan

iTrader: (3)

Yes, you are correct, the price is $6k for you.

Builder

Amazing, but that's a carb engine from Gail at American Speed in IL. in Gareth's GTR. But, that wouldn't be as much fun as building my own. To get the performance I am looking for, Gail would charge something like $26k for a dry-sump version with no warranty. The Brits are good with SBCs. But, I dare say that there is more knowledge on this board than is generally available in the UK. Purchasing a complete engine is a great option, especially for someone overseas. I really like the idea of running a lower compression setup with boost available when needed.