stock turbo times... besides Ed Brewer.....?

[evil666]

Do most of you guys lock the torque convertor, and if you do how much have your times droped and how much MPH have you quys gained?

Thanks.
Marco.

86 Grand National t-top (59900km)
stock long block,stock suspension, red stripe convertor, te44, smc alk injection, 24lbs boost, 94 octane, hooker cat back with dyno max ultra flow muffers, tomco 30lbs injectors, dynotech stage 4 street chip, thdp, mease 24 row IC, Ron Custom max boost brake module, MT drag radials (275/50/15) 3800lbs race weight with driver.
BEST E/T
60FT=1.52
1/8= 7.38
I/4= 11.74
MPH=113
BEST MPH= 114

 

[KEVINS]

The lower the rpm, the higher you can crank the boost and still make more power. You will be blowing nothing but hot air at 4800 rpm and 25+psi boost. Way out of the efficiency range of the turbo. My 111mph runs were with 26*. I ran a 29.5in slick.

I only run 21-22psi max. At 23psi the times fall off a lot with the stock IC.
I need/want to run 112mph and it definitely falls off on the top end so I will have to revisit the issues and see if I can figure out why. I feel that 12.1's @ 109 mph shows me there is something limiting my top end power. I really thought the two different WOT timings would show something but it didn't give me anything to look at. Even locking/unlocking the converter didn't do anything... Oh well, the quest continues..

ks

 

[UNGN]

Do most of you guys lock the torque convertor, and if you do how much have your times droped and how much MPH have you quys gained?

Locking the converter is usually worth about .2 and 2 mph with a D5.

Stock turbo/intercooler/injectors, my car has gone consistant 12.2's@110 with crappy 1.8 60fts.

With a TA49/big neck and Blue tops it went 11.53 and 118.31 with 275/60 DR's. Unlocked it would be in the 114 range with 28" tires.

I lock at the line and it locks up after the 1-2 shift.

 

[murphster]

Both myself and pacecarta lost time switching to 28" tires last year on the stock turbo. We gained mph but it bogged down the 1/8th too much. Looking at your timeslip, I notice a couple things where you can gain. Your 1/8th time will need to get down into the 7.7sec range or lower. Having a better 60' will help, but its not like you had an awful one. You gained 20mph from the 1/8th to the 1/4, which isn't bad. Locking the converter, you should gain 22-23mph or so.

The first thing you need to do is lower the air pressure in the drag radials to 20-22 psi. While some people run lower pressure, a lot of people have had success at these pressures and it will give you the most mph.

Also, leaving harder on the launch will not necesarily make you go faster. Every car is different and it will take trial and error to see what works best. On my car, leaving at 5-6lbs of boost gives me 1.6 60's. Leave with less and it bogs a little, leave with more and I spin. On the other hand, pacecarta leaves with almost no boost and gets low 1.6 60's and sometimes 1.5's. We both have the same MT drag radials you have.

Keep playing with the fuel until you get numbers the car likes. You can try running it real rich vs running it a little on the lean side, but I wouldn't run it too lean. Most alky cars like it on the rich side, if anything.

Also, you can probably add more timing and see how the car likes it. I ran 27/25 timing on my TT alky chip last time out with no knock. Something like 27/23 or 27/22 would probably be a little safer though.

While getting 11s might seem like a mile away, dialing these little things in are the key to shaving a .1 here and there.

Definitely hot-wire the fuel pump. And getting a power plate will give you a little more safety margin next time you go lean. Getting the grainger valve may help or hurt the launch. You may spool up too quickly and lose grip right after the launch. Or it may help. Will help boost creep though. Also, with alky you might be able to push the boost up to 24-25lbs eventually. You should at least go to 23-23.5 lbs of boost. With alky, you will see it will eventually stop making more power, but it won't knock (too much) as the alky will keep the temps down.

 

[bison]

If you use tall slicks like i did (29.5in), then you have to leave at 10psi to take advantage of them. I got high 1.50's with nothing but an airbag. Wuth suspension work like shocks all the way around and relocating the control arms i know low 1.50's are possible and could have run 11.60 or better with my old combo (8 years ago) and stock parts. The tall slicks keep the rpm down and you have more room to go faster with them before the turbo is out of steam at higher boost pressure like 25psi. Locking the converter in 3rd i noticed about .1 and 2-3mph in the 1/4.

 

[Blazer406]

Lower the shift rpm (4600-4800) and run the tallest slick you can get in there. Raising the shift rpm will slow you down. Crank the boost as high as possible. The lower the rpm, the higher you can crank the boost and still make more power. You will be blowing nothing but hot air at 4800 rpm and 25+psi boost. Way out of the efficiency range of the turbo. My 111mph runs were with 26*. I ran a 29.5in slick.

I was letting the tranny shift itself.... it will shift itself close to those RPM's when the tranny isn't real hot..... the hotter it gets though.... my shift RPM's continue to climb... with the highest I recall in previous track visits.... around 5400 RPM per my DS logs......

 

[Blazer406]

.......Looking at your timeslip, I notice a couple things where you can gain. Your 1/8th time will need to get down into the 7.7sec range or lower. Having a better 60' will help, but its not like you had an awful one.

I should be able to get there... just some 60's in the 1.50's would do it for sure..... If my math is correct.... looks like I need a sub 7.60 pass to go in the 11's...... that is .4 seconds off my 8 flat pass... I see .2 in the 60' for an improvement goal..... that .2 in the 60' might get me .3 in the quarter.... Seem reasonable?

You gained 20mph from the 1/8th to the 1/4, which isn't bad. Locking the converter, you should gain 22-23mph or so.

The first thing you need to do is lower the air pressure in the drag radials to 20-22 psi. While some people run lower pressure, a lot of people have had success at these pressures and it will give you the most mph.

The main reason I didn't lower the air pressure... is I put the tires on for the first time right before I took off for the track.... and the rubbed the fender lips on bumps and pretty bad on launch....was scared if I lowerd the pressure any... the sidewall would bulge out more and rub more... planning on rolling the fender lips before I go back.....

Also, leaving harder on the launch will not necesarily make you go faster. Every car is different and it will take trial and error to see what works best. On my car, leaving at 5-6lbs of boost gives me 1.6 60's. Leave with less and it bogs a little, leave with more and I spin. On the other hand, pacecarta leaves with almost no boost and gets low 1.6 60's and sometimes 1.5's. We both have the same MT drag radials you have.

I am not necessarily looking for a faster pass.... just a quicker one.... Your above analogy makes me wonder where the differences in your car and pacecarta.... boost control..... does his spool up faster than yours? What are the differences in the converter.... I plan on having the grainger valve installed before I go back....hopefully it will spool so fast... I won't need to leave on much boost therefore making it easier on the tranny b/c I won't need to build as much boost as I would if it spooled slow... to get the same 60'.... ie. fast spooling car leaves at 2# .. and cuts a 1.5 50' ... and the same car... with a different boost control method... that spools much slower... (all other things being equal).... might need to leave on 12# to cut the same 1.5 60' time..... Make any sense?

Keep playing with the fuel until you get numbers the car likes. You can try running it real rich vs running it a little on the lean side, but I wouldn't run it too lean. Most alky cars like it on the rich side, if anything.

Also, you can probably add more timing and see how the car likes it. I ran 27/25 timing on my TT alky chip last time out with no knock. Something like 27/23 or 27/22 would probably be a little safer though.

My chip is an oldie.... probably going to order a new one soon.... it wouldn't let me adjust timing except WOT.... and that moved it for all gears...ie 23/19 I think was the base setting..... I am stuck with the 4 deg split..... when I move it up.... I can increase timing.. like I already did... but it keeps the same 3 deg split.... I am at 25/21 now....

Definitely hot-wire the fuel pump. And getting a power plate will give you a little more safety margin next time you go lean. Getting the grainger valve may help or hurt the launch. You may spool up too quickly and lose grip right after the launch. Or it may help. Will help boost creep though. Also, with alky you might be able to push the boost up to 24-25lbs eventually. You should at least go to 23-23.5 lbs of boost. With alky, you will see it will eventually stop making more power, but it won't knock (too much) as the alky will keep the temps down.

The fuel pump hot wire is next on my list of things to do.....after that... front swaybar removal.... and hook up my auxbox that goes with the LM1... so I can log boost through the run... and RPM's.... and wideband... all together.....

I think I can improve greatly on what I have..... just don't know how much.... before I change turbos.....

 

[UNGN]

I was letting the tranny shift itself.... it will shift itself close to those RPM's when the tranny isn't real hot..... the hotter it gets though.... my shift RPM's continue to climb... with the highest I recall in previous track visits.... around 5400 RPM per my DS logs......

5400 RPM is way too high for the stock motor/turbo. You stopped making power at about 4800 and the motor has to struggle for the next 600 rpm. If it doesnt shift to 3 by 5000 RPM, adjust the TV cable until it does.

 

[Blazer406]

5400 RPM is way too high for the stock motor/turbo. You stopped making power at about 4800 and the motor has to struggle for the next 600 rpm. If it doesnt shift to 3 by 5000 RPM, adjust the TV cable until it does.

This was after the tranny was pretty hot.....after like 3 passes in 20 minutes.... It appears to shift fine at 4700-4800 when the tranny is fairly cool (i.e. the first pass)....

New tranny is in the works in the next few months... current one is stock and has 149k miles on it.....

 

[bison]

5400 RPM is way too high for the stock motor/turbo. You stopped making power at about 4800 and the motor has to struggle for the next 600 rpm. If it doesnt shift to 3 by 5000 RPM, adjust the TV cable until it does.

Dont do this. You need maximum TV to keep the apply pressure as high as possible or the direct clutches will burn quickly. Especially in a nearly stock transmisson. The correct fix is to get a diiferent governor or add stiffer springs to you BRF governor.

 

[murphster]

I should be able to get there... just some 60's in the 1.50's would do it for sure..... If my math is correct.... looks like I need a sub 7.60 pass to go in the 11's...... that is .4 seconds off my 8 flat pass... I see .2 in the 60' for an improvement goal..... that .2 in the 60' might get me .3 in the quarter.... Seem reasonable?

1.50's would probably be a little optimistic. Lets say flat 1.60's. Might get you down .15 in the 1/8 and close to .2 in the 1/4. That puts you right at 7.8. To get down into the 7.6's or so, you'll need to make more power either by adding more boost or more timing along with tweaking the alky and fuel.

I am not necessarily looking for a faster pass.... just a quicker one.... Your above analogy makes me wonder where the differences in your car and pacecarta.... boost control..... does his spool up faster than yours? What are the differences in the converter.... I plan on having the grainger valve installed before I go back....hopefully it will spool so fast... I won't need to leave on much boost therefore making it easier on the tranny b/c I won't need to build as much boost as I would if it spooled slow... to get the same 60'.... ie. fast spooling car leaves at 2# .. and cuts a 1.5 50' ... and the same car... with a different boost control method... that spools much slower... (all other things being equal).... might need to leave on 12# to cut the same 1.5 60' time..... Make any sense?

There is no real magic boost to leave at. Between the chips, suspension, converter, turbo condition, yadda, yadda, no two cars are alike. Only after many runs will you find out the best combination. Maybe your car will like leaving with more boost, maybe not. Basically, you want to leave with the most boost your car will handle without spinning, grainger valve or not. Pacecarta took off his boost controller, launched with less boost, and had even better 60's! So, its hard to predict what works. For a while, pacecarta and myself had identical chips, tires, injectors, rear bar, and converter. Our cars still launched totally different. Just too many other variables. The only thing I know for sure, is that I have to leave with more boost on 28" tires compared to 26" tires to get the same 60'. The best thing will be to write down all of your settings for each run and make your own baseline so that you can get an idea what works for your car. I made a spreadsheet of all my runs and write down just about everything I can think of. Now I can go back and see how the car started running slower when I blew my rear, then fuel pump went bad, then plugs fouled out, and finally my turbo was deteriorating the whole time. The best three things I did to the car were the HR bar, MT drag radials, and alky kit.

My chip is an oldie.... probably going to order a new one soon.... it wouldn't let me adjust timing except WOT.... and that moved it for all gears...ie 23/19 I think was the base setting..... I am stuck with the 4 deg split..... when I move it up.... I can increase timing.. like I already did... but it keeps the same 3 deg split.... I am at 25/21 now....

4 deg split isn't bad. You could eventually run 27/23, which would be about the most you'll want. The most advantge you can get from a new chip is you could send Eric a DS file of your run. Maybe you are too rich on the launch, too lean up top, etc. He could taylor the fuel curve more to your cars needs, along with some other tweaks.

 

[Blazer406]

I was mistaken on my chip.... it is a 3 deg split.... I am at 25/22 now..... not 25/21 as I previously stated....

As far as my goal of 1.50's.... I got that goal from Ed Brewer.... he went 1.50's maybe even dipped into the high 1.4x's ..... like I said... it is a goal.... I should probably be content with some 1.60's like you suggest.

There is a race coming up on the 18th. I might go down there. I would compete in it just to get some runs in.... there will be many other street legal cars there than can wax me.... I just need to make some passes.....

 

[Blazer406]

The best three things I did to the car were the HR bar, MT drag radials, and alky kit.

got it..... got it..... and got it..... check, check, check....

 

[UNGN]

Dont do this. You need maximum TV to keep the apply pressure as high as possible or the direct clutches will burn quickly. Especially in a nearly stock transmisson. The correct fix is to get a diiferent governor or add stiffer springs to you BRF governor.

If the Car is shifting at 5400, it's probably out of adjustment. He shouldn't need a new governor or stiffer springs.

 

[Blazer406]

To the best of my understanding..... the ONLY way to properly adjust the TV cable is to depress the tab..... slide housing toward the firewall until it bottoms out... then depress the throttle to wide open (engine off of course)... this will alow the TV cable to self adjust to the proper length for the designed internal pressures and shift points. If you depress the tab and slide it out any further..... this decreases the internal pressures (and consequently shift RPM/shift firmness) at any given throttle opening and is a no-no from everything I have read. The decreased pressures could lead to premature trans failure...... at least this is how I understand it...... I have read posts where people suggest that but I never give it any merrit because of the technical info I have found on it that says otherwise.

Right, wrong, or indifferent.... this is what I understand.

 

[bison]

If the Car is shifting at 5400, it's probably out of adjustment. He shouldn't need a new governor or stiffer springs.

Its correct (the TV adjustment) if you are getting max TV at WOT or just before WOT. The TV cable and bracket will stretch and pull when the TV is maxed out, but the throttle should still open a little more. The TV should never be pulled back to limit the throttle valve position at WOT. If hes at max TV and WOT and it shifts too high for his application then he does need stiffer springs or a different governor with heavier weights. Its possible someone changed springs on the shift valves or increased line pressure by some means raising the shift RPM.

 

[bison]

To the best of my understanding..... the ONLY way to properly adjust the TV cable is to depress the tab..... slide housing toward the firewall until it bottoms out... then depress the throttle to wide open (engine off of course)... this will alow the TV cable to self adjust to the proper length for the designed internal pressures and shift points. If you depress the tab and slide it out any further..... this decreases the internal pressures (and consequently shift RPM/shift firmness) at any given throttle opening and is a no-no from everything I have read. The decreased pressures could lead to premature trans failure...... at least this is how I understand it...... I have read posts where people suggest that but I never give it any merrit because of the technical info I have found on it that says otherwise.

Right, wrong, or indifferent.... this is what I understand.

This info is correct assuming the adjuster isnt worn out, or the bracket on the plenum isnt bent. The critical thing is that the cable should not have any slack at all at WOT. The TV must be maxed out at WOT or just before WOT.

 

[evil666]

Blazer406 my best 60ft time was 1.52 and this was done on M/T drag radials (275-50-15). You had to much air in your tires, my car worked the best with 16lbs of air. I have a completely stock suspension and come out at 9lbs of boost which is at about 2900 rpm with my torque ( Red stripe 12" 2800 stall convertor). The guys on this forum are right depending on car and set up there is different ways of launching the car to cut the best 60ft time. With time and practice, trial and error you will eventually get your set up right. Good luck with your goals.

Marco

86 Grand National t-top (59900km)
stock long block,stock suspension, red stripe convertor, te44, smc alk injection, 24lbs boost, 94 octane, hooker cat back with dyno max ultra flow muffers, tomco 30lbs injectors, dynotech stage 4 street chip, thdp, mease 24 row IC, Ron Custom max boost brake module, MT drag radials (275/50/15) 3800lbs race weight with driver. ( Convertor not locked)
BEST E/T
60FT=1.52
1/8= 7.38
I/4= 11.74
MPH=113
BESTmph=114

 

[Blazer406]

Unless there was knock on the 2-3 shift, 106 mph on that run sounds like you are out of RPM.

What is your RPM through the traps?

If its 5000-5200 RPM at only 106, time to switch to 28" tires or lock the converter.

Looked closely at my DS logs tonight..... for the first time since glancing at them after each pass at the track.....

Looks like I came through the traps on that 12.65 pass at 4750 RPM in 3rd..... mph was 105.98 I think.....

o2's were in the 720's at the traps...... I guess that dutt neck i/c leaned out my tune..... I have never been that lean on the top end of the track.....

Every pass after that I bumped the fuel in the chip up more every time..... my best MPH .... was on the last pass.....I left the shifter in OD... so it shifted when it wanted to....... 1/2 was at 4950 ..... 2/3 was at 4600 ..... 3/4 was at 4550 ...... it did go into OD before I let off.....3225 RPM's when I let off........ 107.69 mph or so..... about 812 mV on the O2's when it came through the traps.....

I originally thought I was much leaner.... but after closer inspection...... I wasn't as bad as I thought....


As far as knock..... first pass was the leanest (started adding fuel in the chip every run after that).... I did have 2-3 degrees of knock retard near the 2/3 shift..... ...... highest knock was 4.9 deg @ 4300 RPM with a corresponding O2 voltage of 753 mV ....... looking at the log..... knock retard started about 50 mph..... and continued up and down throughout the rest of the run with a high of 4.9 deg......


On the last pass.... the richest.... and best MPH ..... I had less overall knock..... but it got 6.3 deg when it shifted into OD...... just before it shifted...... I was at 796 mV ..... no knock......

 

[J Banning]

And do you really want that big long cutoff battery switch sticking out the back of your car, especially if you drive it on the street.

Sure... if you use the right kind of switch.

When I take the little red "on/off" decal off the bumper, you don't even know the switch is there...

-Banning.