I'm finally starting to build a 275 radial car and hope to run ultimate street/real street or whatever class is around in the South next year (if its done).

I have raced outlaw VW's (turbo/nitrous) for a while and finally got into lsx stuff after getting my 98 Z.

My first turbo vw was a cheap 1915cc with a T3/T4 on VP 116 that made 27lbs boost every pass and ran 7.10's in the 1/8 at 102. I was really impressed with how hard it would pull on boost.

So I want to use the same basic principals and build an lsx turbo car. I want to build it for ORTC and simliar 275 rules. Right now, ORTC is a non-reduced 80mm @ 3200lbs I think..

So what I did was get compressor maps of the 80 and figure out where the efficiency island was, and work backwards from that.

What I found, was a 370ci Iron Block (+.030) shold be perfect for my HP goals (1000HP at motor) and around 850 to the ground using %15 loss.


So would a 75 Lb/Min estimate be close for a 6.0L with something like a good patriot or AFR 225 head?

I was thinking of a N/A goal of 500 and put about 17-18lbs boost on it to make the 1000HP. The reasoning for putting 18lbs on it was the turbo was %80 efficient on the compressor map and I figured 1 bar (14.7) should double the engine HP so I added for heat loss by bumping up a few pounds of boost to make it even out. working in the efficiency island of the turbo is really going to help keep IAT down and allow more timing and room for mistake in the tune-up.

For some reason I like the idea of shorter stroke 370 at around 17-18lbs vs a more expensive long stroke/rod motor like a 440ci on lest boost with the 80mm.

Also seems like the larger engines are getting WAY out of the efficiency of the 80 maps I have seen and may even be around choke or surge lines.


I'd like to know if my line of thinking is on the right path before I spend too much time planning the 370 and 80mm to make 1000HP at the crank, and this would be enough to get a 3200lb car to 5.3-5.5 in the 1/8 somewhat consistently.

Induction would be intake/billet tb/tb/ to cold side and managed by BS3.

 

1000 turbo hp won't go 5.30 at 3200#. You'll need to rethink/recalculate that.

Aren't Patriot heads base on OEM castings. If so, they are not in the same league as an AFR, or any other aftermarket casting.

 

Do a search, hellbent made over 800rwhp on a stock lq9, I think he had a borg warner 80mm turbo.

 

I think 1000 turbo hp can do 5.30's. I have a forged 370, Patriot stage 3 317's. Th400, with a converter that is slipping to much. Only 9 psi of boost from a precision gt42-76. The car made 576 whp through the th400 and 9 inch, so is probably around 700 or so motor hp right now. First time out to the track we got a 9.87 @ 134. Here is the full slip. As i get the car dialed in i plan to run the 76mm up to 14+ psi and make 700 whp. close to 900 motor hp, I bet im really close to the 5.30's when my car is fully dialed in.

On this run my car was 3250# with the driver.

Full slip:

60' 1.372
330' 4.012
1/8 6.252
MPH 109.62
1000' 8.208
1/4 9.878
MPH 134.48

http://www.youtube.com/watch?v=LKiOwM6txQE

good luck, chris

 

I have heard a lot of good things about patriot heads, plus marty is local and supports a lot of races here in Alabama.

With the right cam combo and tune it should be 500hp at the motor NA. Add 18-19# boost and it should make right around 1000HP at the motor. With the 370 and 80mm turbo the efficiency on the compressor map is 80-85% so that should really keep down the intake temps and allow a little more timing and boost since its so efficient.

eventually, I would like to get the car down in the low 5's to be competitive in some type of real street/ultimate street class. but in the mean time, I just want to get the car built.

Just bought a 96 TA roller with a 9" and full suspension so now I have to decide if I want to put the parts on my street car or just use the TA and build the LSX turbo motor for it.


What HP goal should I have to put a 80mm 370 lsx in a 3200# car running low 5's? I thought 1000HP motor and 850rwhp should do it?

May have to look at turning the boost up to about 25lbs and try to make 1000 RWHP

 

98z28cobrakiller should chime in here soon. He has a 370 with an 88mm turbo and AFR 225 heads and at ~3600# he has gone 8.98@151.

His car is a good base to go off of because it is close to what you are planning out.

 

Thats the combo I really wanted based on the compressor maps for a 370. The 88 should be very efficient. But most of the rules for ultimate street/real street in the southeast (ORTC) limit to a 80mm...

8.50 in the 1/4 is like a 5.50 in the 1/8 right?

 

I think "98cobrakiller" is using a pt88 which is a t4 hotside I believe. You would want something with a t6 hotside for competition use. Call up Precision turbo and see if they have come out with their billet comp wheel for the 80mm.

 

yup, I was wanting to build it with a T6 hotside. This week I'm going to call precision and bullseye to get pricing and compare the two. Also leaning towards e85 but again, have to look at the rules to see if I could run it. Dont see why not since its pump gas

 

i would like to know the same..why couldnt a set up like this in a car with the right suspension and right weight run mid 8's?

 

what are the specific turbo rules...can you run a sleeved 88mm?

 

700WHP Will not get you close to 5.30's. unless you think 5.7's is close?

 

Give us a shout.....we can build you whatever you want. 5.30's can be done with the right unit.

 

It depends on which series. I think ORTC says No reducers, then other x275 says reducers are ok..

I'd rather get a 88mm because I think that it would be better with good heads on a 370. So I'm going to sit down and pick a few races and decide on turbo, but probably a 80mm to be safe.

My luck I would spend 2k on a turbo and the rules would change to allow reducers etc.

 

i hope to be close to 3250 race weight, and 1100 to the motor. threw my drive line around 925 rwhp on 275's should be fun.
play around on this.
http://www.golenengineservice.com/html/calculators.html

 

I'm going to keep an eye on this thread, some good info going on in here...

 

If you want an 88mm to rock and roll.....the new GT5588 ET-R



WELL OVER 1000rwhp...lol

 

x275 and ultimate street go off of 2 different rule sets, to be competitive in x275 you need to be in the 4.70-4.90 range

 

Yeah- I would want to race ultimate street, 4's is out of my play budget for now. I have a good 95 TA drag roller with a 12pt cage and suspension. Just need to build a iron 6.0 block motor and throw the boost at it.

I got a d1sc but will probably sell it and do the turbo kit.

 

Knowing what I know now, I'd definitely recommend a T6 exhaust housing. I've only been 5.78 to the 1/8 but I'm just over 3800#'s and optimized for 1/4 mile. Different gearing and a major diet would likely get me into the 5.4's but 5.2's is knocking on a 7 sec 1/4. You're talking some big muscle there. It'll need to be max effort.