TA

iTrader: (1)

Please just post if you will be running you car on the Dyno Saturday:

1) Kevin
2) Don
3) Troy
4) Julie
???

wolverine350r

iTrader: (1)

I will be the low powered car there, but probably not until 10 or 11, and thats if traffic is clear. Can someone PM their cell in case I can't find it? Thanks.

JulieGTA

What time is this supposed to take place again? ZZZZ.

Oh, ok after 9 am.

Burnout91

I'll be there in spirit, pulling for eveyone to come away with some good numbers! (I know you will.)

Bill

TA

iTrader: (1)

I took off my sunglasses in someone's car (Julie?) Can I get them back please?

TA

1989GTATransAm

iTrader: (3)

Hey TA pretty slick move with the old sun glasses trick. By the way TA was very instrumental in getting the cars hooked up and unhooked. Also did some seat time on the dyno runs. He put in a good days work. Others as well.

I want to congratulate Julie for her cars performance. It was probably the biggest surprise if you will. It would have but down more power but the motor needed more fuel than the system could deliver. Hopefully its only the fuel filter. She was down to 30 pounds at WOT and 100% injector duty cycle.

I think our cars will put in a very good showing at the F-Body invasion this Memorial Day. We will have a good number of solid 12 second cars. 4th gens beware.

Russ-So Cal

I hope you guys will post some numbers. I am curious to see how the various cars did on the dyno.

Kevin91Z

iTrader: (1)

Julie had some great new numbers after her cam swap, and Pat's engine in Don's car put up some great numbers as well. I'll let them post it.

My car is down on both HP and TQ since the last dyno with this combo back in February. I dont know if its because I didnt change the oil, or because its dirty from a year's worth of daily driving, or something changed after removing the 3.5" Dynomax race muffler, or what. I cant remember the exact numbers, but it made around 343 RWHP and 350 RWTQ capped up, and 351 RWHP and 363 RWTQ after opening the cut-out. Don has all the dyno runs on his computer.

JulieGTA

I'm not sure about the numbers, but it ended up being somehwere around 320rwhp and 370tq!
I was only hoping to break over 300 HP! (Previously it was about 285/330)
Thanks, Don, the car has come together well after all that work, and thanks, Kevin for the tune. I picked up like 30 hp!

Aha, they were hidden! When & where can I give them back?

Long Beach Z-28

iTrader: (1)

Now Julie is definitly a force to be reckoned with, and with her ability to cut .001 lights, we are all gonna be in deep s--t!!

85gulstrandTA

posting the car's information with the dyno info. would be great.
if there was a baseline to show the improvement of the parts used would also be information people could use to make thier choices also.

Dyno Don

iTrader: (7)

Julie put down 321/377 .....stock block 350/long runner

Pat's engine in my car put down 351/378...355/short runners

Kevin91Z

iTrader: (1)

The engine specs on my car are here:

http://www.sc3g.org/phpBB2/viewtopic.php?t=690

And you can read about the previous dyno results on my engine on the TPI board, in the sticky post "Our quest for a better flowing TPI."

TA

iTrader: (1)

Yea, 325 HP and 328 Lbs/Ft of torque on my long-tube 383, so Julies' high mileage stock shortblock 350 would put the hurt on me. Somehow in converting to long tubes and true duals with an X-pipe, I managed to gain 12 HP and loose 46 Lbs/Ft of torque. Whatever was not right before is even more not right now.

TA

injdinjn

Not enough $$ for trial and error.
When Yamaha brought out that crotch rocket to compete with the HD I read that they went thru a train car load of exhaust systems before they got the sound they wanted.

1989GTATransAm

iTrader: (3)

TA, I had you down for 334rwhp and around 345rwtq on you best dyno pull. You started out low but kept gaining with each refinement of the tune.

TA

iTrader: (1)

Maybe that was uncorrected? I had those figures in my head as well, but unless I'm missing my last dyno run, it was not a great showing for the stroker.

TA

Russ-So Cal

What heads and intake are you using? The info is probably on the board somewhere, but I'm lazy right now!!! The stock tpi is designed for the 305 and marginal for a 350. Most aftermarket tpi systems are designed for the 350, but may be marginal for stroker motors. Since your numbers are in line with the 350s that were tested, it would seem that you may not be getting enough air in and out to make the power that a 383 should be capable of doing.

TA

iTrader: (1)

My heads are ported Edelbrock E-tec 200s and the intake is a ported Edelbrock Vortec adapter, with an unported SuperRam on top of it, fed by an SLP cold air intake and a BBK 58MM throttle body and gutted maf.

TA

injdinjn

Fixed

TA

iTrader: (1)

Fixed? Like a dog fixed? ...no wonder it has "no *****"

TA

Russ-So Cal

You didn't mention the exhaust system. Have you done anything to the exhaust system?

TA

iTrader: (1)

The exhaust was the only thing I did change: From Shortie Hookers/single cat/4" mufflex to Dougs (Same as Hooker) long tubes, into a true dual system/X pipe/dual cats.

TA

1989GTATransAm

iTrader: (3)

TA, from your standpoint I would be wondering why the torque is so low in comparison. The horsepower is an air flow problem in the higher rpms and I believe you have the solution for that.

It could be with the new exhaust the "wave tuning" is at the worst possible amplitude. Might be as simple as moving your x pipe to the proper location if that is physically possible. Or maybe just eliminate it and see what happens.

TA

iTrader: (1)

You were on the right track. I spoke to Darryl Bassani, who designed the true-dual exhaust system, and he explained that running cats after the x-pipe, especially on long-tube headers, just in front of the rear axle is most of my problem.

The long-tubes and distance allow the exhaust gasses to cool substantially, but when they get back into the converters, which "light off", they raise the temprature back up from about 500 to almost 1500 degrees. This temprature increase dramatically increases the pressure in and after the cats, and is like blowing high pressure air back up my tailpipes.

He also says that if it is also intake restricted, it will make this effect even worse. He didn't expect it to make that much difference, but he predicts that if I move the cats as close to the exhaust ports as possible (gee, all newer cars have cats as far forward as possible, don't they?) and open up the intake, it will be a whole different animal.

(Sigh) Hack up my exhaust and try again...

TA

1989GTATransAm

iTrader: (3)

Hmmmmm. Thanks TA for the information. That "might" be a problem for me. Per side I will be using a short tube header, exhaust termination box then catalytic converter then a y-pipe to join both sides and of course the single 3.5" pipe to the muffler.

The exhaust termination box will cool the gases as they expand. I will use a thermal barrier inside and out on the termination boxes to keep as much heat as posible inside. Maybe insulate the pipe with thermal barrier all the way to the converter.

injdinjn

Me too and Im not done hacking yet.

Dont feel bad, Yamaha went thru a train carload of exhaust systems until they got the right sound for the crotch rocket they made to compete against the H-D. So we are just getting started.

TA

iTrader: (1)

Even if you insulate it, the expansion in the chamber will cause substantial cooling, and the "light off" of the converter afterwards will create a pressure plug in your exhaust. You might gain a few HP, but not what the potential of the system would otherwise give you. Find a way to move the cats forward, trust me.

TA

1989GTATransAm

iTrader: (3)

I will have to give this some more thought. Thanks TA

JulieGTA

I am working on making a sig to show my mods, hope that helps.
I usually don't like tacking them on...

Ok I made a sig with my mods (see profile). I am trying to figure out how to fit more in it.

Kevin91Z

iTrader: (1)

The dyno was set to correct to Standard. Nothing was uncorrected.