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More Than Meets the Eye
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Discussion Starter #1
This was at Silver Dollar Raceway, Reynolds GA

Finally had a chance to take my car to the track and wouldn't you know, the damn thing wouldn't quit sputtering at WOT. 14psi, 100 octane unleaded.

Racing at 90% throttle I got back to back 13.5 @ 101 so I wonder what it can do WOT. I'm doing more troubleshooting today and if all else fails I'll get a datalogger so I won't be shooting in the dark anymore.

Ukyo was there in his automatic GSX. We unplugged the wastegate hoses completely and it didn't run a tenth difference either way. WTF? More investigation is needed there too. It should have picked the car up a full second at least.

Also saw a serious sleeper Trans Am. It was a twin turbo LS1 but you couldn't tell it by looking under the hood. He was running 12.4s @ 117 that night with traction issues.

Sean Z (black 93 TT) raced a 10th Anniversary Firehawk to a nailbiting loss of 13.25 @ 106 to 13.24 @ 107. His Stealth has 135k miles and has only a K&N and bleeder - nice going!
 

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Devoted Darkling
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I had a nice reply posted out with all the gory details of the night and my 2G Turbo DSM vs. 3G Eclipse GT (V6) battle, but the stupid server [email protected]#ked me over and lost it all. So, instead, here's the summary:

The Eclipse GT beat my Eclipse GSX 3 - 1. Over all I had the fasted ET of the night with a 15.539 @ 86.06, but that was the only run I won. Every thing else I did was in the low 16s. His Eclipse GT pulled a best time of 15.782 @ 90.12. We both got these times on our second run. In a small way I proved my car is quicker, but in the end his car is by far faster.

John -

It was good seeing you and Sean again! Thanks for the tip on the boost solenoid hoses. It helped, but not as much as we were hoping. I think with the hoses pulled and a 1.9 60' the car will get dangerously close to the 14s. All I need is some more practice. ;)

Sean mentioned you guys may know someone that can help me out with my tranny. If that is so, I'm all for it. I foud a shop out in Smyrna that can rebuild it for a fair price, but if I can get it done and maybe be a part of the repair, I am all for it. Let me know please!
 

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Devoted Darkling
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John -

I've been thinking a lot about the GSX times. Sure, dropping from a best of 16.313 down to 15.539 is a good step, but I felt the car should be faster than that... especially with new plugs and full boost. I know with a better 60' it should be in the low 15s, but I think it should be in the high - mid 14s. Here is my theory:

Too much boost. Blasphemy I know, but maybe there was just too much boost. I have not looked at the flow rates for the T25, but maybe running it all out like that would make it stronger, but out of it's effiecency range. We got more power, but we got more hot air, too. Maybe a controlled raise in boost would be better than full boost? Effectively trying to get more useable boost versus just letting it run wide open?

Any other ideas? I can't believe I was trounced by a 3G Eclipse GT with nothing done to it but a drop in K&N filter. :(

And to make this 3/S related... I drove the VR-4 last night. I've got to get that car fixed. Not being able to fully enjoy it is driving me crazy...
 

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More Than Meets the Eye
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Discussion Starter #4
We took my brother's Supra to a guy in Atlanta yesterday for some new valve stem seals and an exhaust cam gear. While we were talking cars, I had an idea about my sputtering. Whenever it happened, the boost gauge needle would vibrate rapidly 4-5 psi in either direction. It is tapped into the fuel pressure regulator line.

I traced the line back from the FPR to its source and discovered that it eventually connects to the plenum in the back, right behind the throttle body. And whadda ya know - that line had a crack <i>on the underside</i>. I had some hose with me and made a change. Fixed it - no sputtering all the way home and we did some spirited driving including a brief run-in with a supercharged Jag. We easily won from 70-120 :)

On the 95 Talon AWD auto I worked on - IC pipe, BOV, bleeder, K&N - the difference between stock and modded was just as big as it is on the 3kS cars. My assometer says it is a 14.0 car at least. Double checking the bleeder setup one day, I discovered that I had the bleeder open far enough to essentially give the wastegate no signal. I turned it down and all it did was make it proportionally slower. Putting it back to wide open gave us no problems and satisfying performance.

My theory in your case is maybe the factory T in the wastegate line has a restricted opening on the solenoid side, meaning you're not bleeding as much as you think you are. On the other car I'd replaced everything while I was in there - new hose and T. If this is the case, when we pulled the hoses you may have gained 1-2 psi.

Want to pick up a spare boost gauge (VDO = $29 at Summit)? You can hook it up temporarily with a hose coming in the passenger window and see what boost you're actually making. If it's 11-12 psi, you're still at stock level. What we want to see is 17-18psi.

btw - Mom's 01 Grand Marquis with the performance package can turn 15.70s @ 88 according to the magazines. I bet I could take a tenth or two off that too :)
 

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Devoted Darkling
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John M said:
We took my brother's Supra to a guy in Atlanta yesterday for some new valve stem seals and an exhaust cam gear. While we were talking cars, I had an idea about my sputtering. Whenever it happened, the boost gauge needle would vibrate rapidly 4-5 psi in either direction. It is tapped into the fuel pressure regulator line.

I traced the line back from the FPR to its source and discovered that it eventually connects to the plenum in the back, right behind the throttle body. And whadda ya know - that line had a crack <i>on the underside</i>. I had some hose with me and made a change. Fixed it - no sputtering all the way home and we did some spirited driving including a brief run-in with a supercharged Jag. We easily won from 70-120 :)
Cool. I'm glad it was something simple. I keep a little hose in my tool box just for situations like that. You never know when something like that is going to happen. I've been thinking about pulling all the factory hose on the VR-4 and replacing it with new, but I don't want to lose the color coding.

On the 95 Talon AWD auto I worked on - IC pipe, BOV, bleeder, K&N - the difference between stock and modded was just as big as it is on the 3kS cars. My assometer says it is a 14.0 car at least. Double checking the bleeder setup one day, I discovered that I had the bleeder open far enough to essentially give the wastegate no signal. I turned it down and all it did was make it proportionally slower. Putting it back to wide open gave us no problems and satisfying performance.
OK, so that blows that theory. Now we need to move on to your theory...

My theory in your case is maybe the factory T in the wastegate line has a restricted opening on the solenoid side, meaning you're not bleeding as much as you think you are. On the other car I'd replaced everything while I was in there - new hose and T. If this is the case, when we pulled the hoses you may have gained 1-2 psi.
Hrmmm... So this restriction would be in effect even with both hoses pulled? Maybe the actual T is a restriciton??? I dunno, but I do have a packet full of nice sized Ts and something to look in to when I get home from work... ;)

Want to pick up a spare boost gauge (VDO = $29 at Summit)? You can hook it up temporarily with a hose coming in the passenger window and see what boost you're actually making. If it's 11-12 psi, you're still at stock level. What we want to see is 17-18psi.
How are those VDOs? Are they as good as the AutoMeter gauges??? If so, I may just get one. I am planning on getting the Lo-Tek 2 pod A-pillar for the Eclipse and run an AutoMeter boost and A/F gauge. I do, however, want the gauges to match. Does VDO make an A/F?

btw - Mom's 01 Grand Marquis with the performance package can turn 15.70s @ 88 according to the magazines. I bet I could take a tenth or two off that too :)
Just what I need, a Grand Marquis giving my car a run for it's money on the track and roasting me from a roll in the Eclipse. Thanks John... you really made my day ;)

I also get to start pricing the 60K service on my GSX. I really hate not being mechanically inclined. :(
 

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just some guy.
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man, I wish I could have gone. that would have been fun.
 

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Devoted Darkling
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Racer_X said:
man, I wish I could have gone. that would have been fun.
It was pretty fun, but the Silver Dollar crew screwed the street cars. The first two times I went out there they treated everyone equal, but the past 3 or 4 times I have been out there they have pretty much ignored the street cars and let the trailer queens have full run of the place.

I do want to see your car on the track, though. Now that you are in the 12s I can't wait to join you!
 

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More Than Meets the Eye
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Discussion Starter #9
In my runs I ran it to redline (or close, depending on the gear) but I could never push the pedal down past 85-90% without it sputtering. It should do much better now that WOT is available.

Phil Panas is doing the work - I think it's in the $700 (parts & labor) range but that's completely off the top of my head. His daily driver is a black 700rwhp Supra with widened (11 inches!) stock wheels and 315-width rubber!

ukyo -

I think the T itself is the restriction. I know the 1g DSMs are set up that way (or maybe it was something in one of the vac lines, I forget). Either way, replacing it all made the difference.

Racer_X -

Yes, another Stealth would have been nice!
 

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just some guy.
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I thought Phil would be doing the work ;). he is a friend of mine. He is doing my buddy Larry's valve seals also. His car was probably up there when you get there (black single turbo to4R I believe with abotu 575 to the ground. auto). from what I hav eseen, Phil does awesome work.
 

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More Than Meets the Eye
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Discussion Starter #11
That car wasn't there but there was a red 6spd one with new Blitz wheels that looked nice. His was BPU I believe.

My brother's next addition will be a FMIC and then a real dyno tuning session. Phil is tuning his AFC via the SOTP method for now.

It should be unfair what Phil has done to his car. A stock-looking Supra with 700rwhp must terrorize the locals.
 

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just some guy.
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HEHEHEHE. With as many single turbo's running around atlanta now, you just assuem that every supra you see is single turbo hehehe. Larry's car even has a stock tip on it :) sneeky sneeky stuff ;)
 
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