Finally got a little tuning session today utilizing the Dynojet Wideband and Tunercat and Datamaster. The first baseline pull with pretty much the stock LT1 program minus a little timing and about 5% added to the PE tables in the upper RPM's yeilded a respectable 468 RWHP and 559 RWTQ. After some tweeking of the PCM i was able to put down 542 RWHP and 622 RWTQ Not to bad for having a stock shortblock with new pistons.

Car mods for those who don't know:

355 LT1 w/ Speed Pro -22cc Forged Pistons, PT-76 Qtrim turbo, ATI Twin intercoolers, AFR 190 CNC heads, Custom Turbo cam from GTP, 42# injectors, Racetronix twin intank pumps (seeing 70 psi with both running) The only thing left of the Turbo tech kit is the turbo header and crossover.

I was seeing a max of 18 psi on the dyno, the pressure kinda went up like a blower car, not like i am used to seeing on the street, guess there is some fact to the whole dyno not putting as much load on the car as the street. Air temps would max out at 49 deg's C by the end of each pull and start around 35. Temps today were around 85 and humid as hell. I'll post the dyno sheet as soon as i get it scanned.

Bill

 

Nice #'s. The only thing I see is, thats alot of boost for 542rwhp. I figured at 14psi or so with a T76 you would see 650-700rwhp. Maybe the header is causing a large restriction. Either way those are good #'s and should be plenty for 10's.

Jose

 

Well like i said, the boost was kinda going up linearly with RPM like a blower car. I usually only saw 16 psi on the street. 18 psi was pretty high in the rpm's. I agree the header is probably a huge restriction, and I have another damn exhaust leak somewhere. It never ends. I am more than happy with the numbers, now i have to work at getting the power to the track, the M6 isn't cutting it off the line. I am probably just to afraid of breaking it again, the last time it cost me $1400 to fix, i should have just gone automatic at that time. I have a TH350 in the works with a brake right now. I still have a NX kit laying around, and i'm thinking that using it now would be way to much for the stock crank and rods. I think I'll keep it where i'm at. Oh and that was on 93 octane too.

Bill

 

You had a similar response to my dyno #'s.

Do you have any links to turbo cars with 5.7L, 14lbs of boost, and 700rwhp?

I'm just curious to compare setups and see what I'm doing wrong

 

i bet Monty's motor makes 700rwhp @ about 14psi considering he has 18* heads that flow 368/24X i believe....LOL

Now with 14psi i can easily believe 700 @ the flywheel but that is a good 800+hp at the flywheel with only 14psi hard to do with a single turbo

jmo though

edit:
i betcha THIS T76 can make 700rwhp @ 14psi. It went 130mph in a notchback with only 5psi

that turbo is for sale at a VERY reasonable price btw, email me for details on it

 

dynojets are not as reliable for real life loading as a mustang dyno is. Not that I have any real life experience but ive been told by people who work with both that is the case. Also you may find that yo need more fuel on the street then you did on the dyno and that all goes back to the same reason. dynojet doesnt load it like real life.

in any case, congrats!

 

Congrat on the numbers.

 

Jim I'm not knocking anyone's #'s. You guys are doing a great job and having running cars, as I don't. I'm just curious. I've been on turbomustangs now for a few months and it seems at 14psi of boost they are running close to 650-700rwhp or so on a built motor such as ours. I'm curious as to why they seem to ~double their rwhp of their N/A setups at that level of boost and we don't. I would imagine on an efficient setup with a H/C low compression LT1 it would make close to 340-350rwhp N/A. With 14psi we should be able to approx. double that #. I'm trying to see if its our head design, header design or a combo of both. Examples, Gary Ramsey with a 331 is running 633rwhp @14psi with a GT80, Brent with a 347 "I think" is making 710rwhp/834rwtq @14psi with a T76, and Dean made 666rwhp/710rwtq @13psi and he's also running a T76 Q-trim. Are we just using to small of cams?? Most of these guys are using heads that also perform very close to our LT1 heads. I was thinking maybe it is the header design. They all seem to run large 1 3/4 tubing and as large a downpipe as possible and 2.5 crossovers, while we use 2 1/4". Plus they use 3" intake tubing, vs most of our setups are using 2.5". Who knows, but I'm sure we should be able to match or surpass those #'s at equal boost levels.

Jose

 

Jose, you may be onto something with your undersized tubing theory and poor header design. The PTK kit you got looks pretty nice but some of the other stuff ive seen, most notably the turbo tech, SUCKS.

And Ford aluminum head design is a few years ahead of LT1 head design improvements too.

 

Jose, I wasn't trying to say that you were knocking the numbers, I was just curious about what you had seen as a basis of comparison.

Those mustangs that you make reference to, do you know what size cams they are running and what RPM they make peak HP?

I'm using 1 5/8 primarys, 2.5 collectors, 2.5 crossover, 3.5 downpipe, and 3 inch induction tubing. I'm also still using my old 214/222 blower cam because I couldn't decide what to change it to.

I chose the 1 5/8 for the primarys because I read a few articles on mustangs with 1 5/8 turbo headers and running 8's and faster. I think the owner of one car was Job Spetter? (sp). I could be wrong, I'm not very good with names.

If I had to guess, I would think that you are right about cams being too small. I'm sure if I switched from my 214/222 cam to a 246/238 cam that 14psi would mean alot more CFM.

 

holy camshaft jimbo get a reverse split in that puppy!

I made 5psi of boost with my small frame 88 and last year when the car weighed closer to 3600 pounds, it went 126mph. That was with a small 232/228 hyd cam in a 406.

You have potential there man. tap it!

 

yea buy my 217/213!


HEHEHE

 

not that im an expert

but i think the lt1 crowd just hasnt hit on the magic combination for a turbo setup on our cars.

there is a weak link somewhere, and its probably having to do with cams, and maybe to a lesser degree tubing sizes.



regardless.........the numbers are still great, especially that torque!!!


btw.........jose, are those mustang hp numbers on race gas? that could make a difference.

 

On SmokinZ's car, it may be the pipes, (header, crossover, etc) that may be costing some hp.



On Intmd8's car it looks like it could be the cam.

 

very nice