John V's STS GTUs build thread
05-22-11, 01:40 AM
#451
maybe when the ACV opens to dump the air pump air, the air pump cannot keep up? its a little odd but it would be a valid move to put a restrictor in the air pump dump hose...
Good thinking, it might be that the stock dump through the silencer is restrictive enough to keep pressure up for the VDI actuator and whatever dump route you have now isn't...
Good thinking, it might be that the stock dump through the silencer is restrictive enough to keep pressure up for the VDI actuator and whatever dump route you have now isn't...
05-22-11, 08:27 PM
#456
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05-23-11, 07:47 AM
#457
I hope the changes have been helping otherwise I've been wasting time. I've changed a lot in the last four months - dampers, ride height, alignment, brake pads, intake, tuning...
The biggest improvement has come from the new dampers. They make the car much more driveable.
Fixing the brake bias issues so I'm not always locking up the rear brakes helped a lot as well.
The biggest improvement has come from the new dampers. They make the car much more driveable.
Fixing the brake bias issues so I'm not always locking up the rear brakes helped a lot as well.
05-24-11, 02:49 PM
#465
A lot of the rear bias problems were fixed by the new suspension, which more manageable rear rebound characteristics. I also lowered the rear ride height. But really what it came down to was using crappy rear brake pads with creative surface-area modification. I'll leave it at that 
05-24-11, 05:05 PM
#466
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Rock & Roll man! Awesome to see you took 1st. So what's next?
Thanks for the air intake data. It was really cool to see the effects of a different intake tube and how much a cold air box drops the temperatures. Any more alignment tweaks made?
I still have yet to take my car out, I've been so busy! I still haven't put the brakes together, but I have everything except for new blank rotors.
Hopefully someday I'll be up to par.
Thanks for the air intake data. It was really cool to see the effects of a different intake tube and how much a cold air box drops the temperatures. Any more alignment tweaks made?
I still have yet to take my car out, I've been so busy! I still haven't put the brakes together, but I have everything except for new blank rotors.
Hopefully someday I'll be up to par.
05-24-11, 05:21 PM
#467
Yeah, little alignment tweaks here and there. I run a bunch of very different setups depending on the lot and the conditions. I would have liked to try more spring rate up front in New Jersey but it just wasn't in the cards - spent too much time chasing the VDI issues (which still aren't solved by the way).
There is still a lot of learning I need to do with regard to setup. The car dances really well but it can always be better
There is still a lot of learning I need to do with regard to setup. The car dances really well but it can always be better
06-03-11, 06:44 PM
#470
Well I towed out to Lincoln with Ian Baker to do the Memorial day pro / tour (aka Spring Nationals). Results really couldn't have been worse.
First of all, my aftermarket radiator decided to split at the filler neck. So after driving 21 hours straight, the first thing I did on site was drain the rad, pull it, and solder it back together. Rather than doing practice starts for the Pro. I finished in time to do a couple coursewalks and wasn't happy. Courses were very tight and transitional - about the worst thing for the RX-7. Also, the forecast for the Pro was rain and very cold temps.
Day 1, I ended up running my rain tires (full tread 225/45/15 Toyos). With little seat time on these tires, I ended up fighting the setup most of the Pro. The car was horribly loose, worse than it's ever been. Lincoln is grippy but bumpy, but I figured it was just my driving. Looking at the videos, I'm not so sure. I was really not trusting the car in fast sweepers nor in the transitions, so my times were very slow. Ian offered me his car to try out on the morning of day 2, but it rained, so nobody picked up time.
In the afternoon it was hot and nice, so I threw the Hankooks back on and hit the Evo test and tune course. Sam Strano, Jr. Johnson and Tom O'Gorman all drove the car. Jr. and Sam loved it. We were all about .2 slower than O'Gorman in a top STS CRX on that course. It was loose, so we took all the rear shock out of the car and it improved, but still wasn't great. I figured I'd make changes during the tour on Sunday / Monday.
Of course, then it rained on Sunday for the tour. I was about 2 seconds off of the top cars, and a second off the Miatas. I honestly don't think this car can hang with the top STS cars in the rain. I was getting wheelspin all through 2nd gear on the Toyos and the car was undrivable in transitions. Just couldn't keep the rear end behind me. At this point I should have checked the rear toe-in and camber, but the racing went so late I just wanted to get some dinner.
Monday was a little better, but I was still more than a second off the pace (about 1.2 behind the top cars on a 70s course). Car was really loose everywhere. At this point I'm puzzled. It's never been this loose in the dry before. Granted, since I didn't have a co-driver, the Hankooks never got any heat in them, but it's never been this bad. Also, I was getting tons of front brake lockup.
My co-driver and another friend are taking the car to the Delaware National Tour this weekend, so I decided to check everything out. Turns out that the rear toe adjusters slipped and I had no toe-in in the back. With the stock rubber bushings back there, that just won't work. I dialed in 3/16 total toe (and thought about putting 1/4" total back there) and put the 275lb rear springs in (I had been running the 300s in Lincoln with 430s up front). Hopefully, those guys will get me some good data.
I've got a plan to fix the brakes (remember, last year I was fighting REAR brake lockup... so my adjustments went too far the wrong direction).
Frustrating after the car being so awesome in New Jersey, but I learned a lot.
1) I think the car needs more spring all around in Lincoln. I have some pictures of the car and there is a LOT of body roll in Lincoln.
2) I think I probably have too much damper in the rear. It got better with taking bump and rebound out of the back and the DAs I have were valved for a car with slicks, not street tires.
3) The car seems really sensitive to rear toe-in, and I need to overtorque the nuts to make sure it doesn't slip.
4) The brake bias is effed, and it makes corner entries really unpredictable.
Unfortunately my Lincoln finish eliminated any chance of me winning the overall ProSolo season, but I'm pretty happy getting one win tonight and if luck is on my side, I can certainly win the Pro Finale and have a moral victory.
Stay tuned...
First of all, my aftermarket radiator decided to split at the filler neck. So after driving 21 hours straight, the first thing I did on site was drain the rad, pull it, and solder it back together. Rather than doing practice starts for the Pro. I finished in time to do a couple coursewalks and wasn't happy. Courses were very tight and transitional - about the worst thing for the RX-7. Also, the forecast for the Pro was rain and very cold temps.
Day 1, I ended up running my rain tires (full tread 225/45/15 Toyos). With little seat time on these tires, I ended up fighting the setup most of the Pro. The car was horribly loose, worse than it's ever been. Lincoln is grippy but bumpy, but I figured it was just my driving. Looking at the videos, I'm not so sure. I was really not trusting the car in fast sweepers nor in the transitions, so my times were very slow. Ian offered me his car to try out on the morning of day 2, but it rained, so nobody picked up time.
In the afternoon it was hot and nice, so I threw the Hankooks back on and hit the Evo test and tune course. Sam Strano, Jr. Johnson and Tom O'Gorman all drove the car. Jr. and Sam loved it. We were all about .2 slower than O'Gorman in a top STS CRX on that course. It was loose, so we took all the rear shock out of the car and it improved, but still wasn't great. I figured I'd make changes during the tour on Sunday / Monday.
Of course, then it rained on Sunday for the tour. I was about 2 seconds off of the top cars, and a second off the Miatas. I honestly don't think this car can hang with the top STS cars in the rain. I was getting wheelspin all through 2nd gear on the Toyos and the car was undrivable in transitions. Just couldn't keep the rear end behind me. At this point I should have checked the rear toe-in and camber, but the racing went so late I just wanted to get some dinner.
Monday was a little better, but I was still more than a second off the pace (about 1.2 behind the top cars on a 70s course). Car was really loose everywhere. At this point I'm puzzled. It's never been this loose in the dry before. Granted, since I didn't have a co-driver, the Hankooks never got any heat in them, but it's never been this bad. Also, I was getting tons of front brake lockup.
My co-driver and another friend are taking the car to the Delaware National Tour this weekend, so I decided to check everything out. Turns out that the rear toe adjusters slipped and I had no toe-in in the back. With the stock rubber bushings back there, that just won't work. I dialed in 3/16 total toe (and thought about putting 1/4" total back there) and put the 275lb rear springs in (I had been running the 300s in Lincoln with 430s up front). Hopefully, those guys will get me some good data.
I've got a plan to fix the brakes (remember, last year I was fighting REAR brake lockup... so my adjustments went too far the wrong direction).
Frustrating after the car being so awesome in New Jersey, but I learned a lot.
1) I think the car needs more spring all around in Lincoln. I have some pictures of the car and there is a LOT of body roll in Lincoln.
2) I think I probably have too much damper in the rear. It got better with taking bump and rebound out of the back and the DAs I have were valved for a car with slicks, not street tires.
3) The car seems really sensitive to rear toe-in, and I need to overtorque the nuts to make sure it doesn't slip.
4) The brake bias is effed, and it makes corner entries really unpredictable.
Unfortunately my Lincoln finish eliminated any chance of me winning the overall ProSolo season, but I'm pretty happy getting one win tonight and if luck is on my side, I can certainly win the Pro Finale and have a moral victory.
Stay tuned...
06-03-11, 09:17 PM
#475
ok, good to know. i'm not sure there can be much more pulled out as that is already pulling on the subframe quite a bit. if you feel there is more adjustment that can be pulled out i can try swapping it out for a different one with more adjustment or a lower adjustment starting point(more negative camber starting than the stock rod).
my car does run 18's so perhaps i thought it was lower than it really is(taller than stock rubber).
my car does run 18's so perhaps i thought it was lower than it really is(taller than stock rubber).
Last edited by RotaryEvolution; 06-03-11 at 09:19 PM.