Tuning the twin turbo

What transmission do you have in your turbo car? How is the transmission brake set up? So you shift through all the gears all the time? I found a lentech manual AOD valve body on their web site. It eliminates the TV cable. Very pricey, is that what you recommend

Ken

It's an AOD that started as a Lentech Strip Terminator that was rated for 1000 HP. I broke it racing the car down in KY at one of the KY HP spring meets, and dropped the car off at Alan's shop for a complete rebuild and numerous upgrades, so now it's a Dirtydog max effort AOD that includes everything Alan could throw at it.

Yes...I'm using the same Lentech manual VB you mentioned. Fixed line pressure, electric OD engage, no TV cable, manually shifted up and down, with trans brake and most importantly includes Reverse/ 3rd torque holding mod that is patented by Lentech. Trans brake can only be engaged in 1st gear, and for best results needs to be wired into an adjustable 2 step rev limiter like I have with the MSD digital 6 box.

David
 
It's an AOD that started as a Lentech Strip Terminator that was rated for 1000 HP. I broke it racing the car down in KY at one of the KY HP spring meets, and dropped the car off at Alan's shop for a complete rebuild and numerous upgrades, so now it's a Dirtydog max effort AOD that includes everything Alan could throw at it.

Yes...I'm using the same Lentech manual VB you mentioned. Fixed line pressure, electric OD engage, no TV cable, manually shifted up and down, with trans brake and most importantly includes Reverse/ 3rd torque holding mod that is patented by Lentech. Trans brake can only be engaged in 1st gear, and for best results needs to be wired into an adjustable 2 step rev limiter like I have with the MSD digital 6 box.

David

Priced on Lentech page is 750 buck a roos. That will have to wait awhile I guess. Not sure Where to go on the two step. A lot of this is pretty new for a newbe like me. What the stall on your black ones transmission. Did you ever change rear end gears or are you running 3.73s still

Ken
 
Priced on Lentech page is 750 buck a roos. That will have to wait awhile I guess. Not sure Where to go on the two step. A lot of this is pretty new for a newbe like me. What the stall on your black ones transmission. Did you ever change rear end gears or are you running 3.73s still

Ken

Yes the Lentech VB is pricey, but it's the best. Alan built a new converter to go with the transmission and stall is around 3300-3500 rpm but can be launched well above that on the trans brake. Still running 3.73s and switched to a larger diameter slick to keep from running out of rpm in the 1/4 mile. New motor Dave is building will be able to rev higher than my old one, so I should be able to get to around 145 mph with the 3.73s.

David
 
Yes the Lentech VB is pricey, but it's the best. Alan built a new converter to go with the transmission and stall is around 3300-3500 rpm but can be launched well above that on the trans brake. Still running 3.73s and switched to a larger diameter slick to keep from running out of rpm in the 1/4 mile. New motor Dave is building will be able to rev higher than my old one, so I should be able to get to around 145 mph with the 3.73s.

David

Well the shootouts almost here so what ever the car does performance is a mute issue. The valve body sounds interesting as I think getting off the line is going to be the down fall of its performance. The 9.5" converter I have is a 3000 stall. Guess I will spend some time learning from you, casey and corey this year

Ken
 
My diesel truck does just fine foot braking the boost up. Just pre stage then bring the boost up as much as you can on the foot brake then just bump it in to stage by releasing the brake slightly. Hell thats what I do with the blower car.

Good luck with it Ken.
 
The dual pumps came with the kit from STS. They have STS on them but I dont know what brand they are. Will have to look and see. Dont plan on nitrous at the moment. I want to see how the car performs on the track first. Im sure it will continue to evolve.

Ken

I'll check their site out. I'm at the point to either drop the coin on on trans brake or spray it into boost. Got to try the new turbo out before making any decisions but I'm thinking it's going to be lazy on my combo.
 
Took the car back to the dyno today. 98 degrees and 1000% humidity. Made just 3 pulls. Car makes the same HP #s as the old cam. nothing gained there:mad: Turbos spooled much faster was my only gain. I do have much better vacuum so brakes are much approved. Car starts and runs perfectly so thats a plus. Pretty tired of putting money in to this and not seeing something come of it. Dyno operator feels the engine and power adder are not the problem, feels the non locking TQ is the problem and no gains on the dyno will show untill I get rid of it. Have to see if the track performance suffers or improves. Wouldnt care what the numbers were if it ran a 10 second 1/4 mile but I dont see that happening. Most guys would be happy to have a 450 horse motor but that pretty sorry #s for a twin turbo. A big block motor is sounding better all the time:rolleyes:

Ken
 
Dyno operator feels the engine and power adder are not the problem, feels the non locking TQ is the problem and no gains on the dyno will show untill I get rid of it.
...
A big block motor is sounding better all the time:rolleyes:

Ken

A big block motor wouldn't solve the problem of the TQ not locking would it?
All I can say is a manual transmission is so much easier when it comes to know what is going on when you press the gas pedal to the floor. sorry to hear of your ongoing challenges.
 
How's it feel on the street, Ken? Switching converters isn't going to add 100+ rwhp or something crazy. Can you send me one of your data logs, what maf are you running, what's your injector duty cycle? I'm thinking you can acquire enough information from your fuel and air requirements to get a rough estimate of crank horsepower.
 
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It is possible it will perform much better at the track than the numbers indicate....mine seems to.
 
A big block motor wouldn't solve the problem of the TQ not locking would it?
All I can say is a manual transmission is so much easier when it comes to know what is going on when you press the gas pedal to the floor. sorry to hear of your ongoing challenges.

If I ever did change to a big block the AOD wouldnt be part of the package.

Car feels extremely strong on the street. Almost like having a rocket strapped on to the rear when it goes into boost. It seems to load the engine which I think the dyno doesnt get done

Ken
 
A locking converter can add over 100rwhp Corey. My bone stock motor with bone stock converter on 11psi with a procharger went from 225rwhp unlocked to 311rwhp locked.

Ken, can you log actual slip like the mustangs or can you calculate and post it? Btw my motor was making 520rwhp(estimated) and the maf counts were 830s with hpx slot maf. You need to take it to the track and go by mph because there is no way you are going to the actual power from a non locking converter on the dyno.
 
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How much boost were you making? Did you play around with boost any?

Waste gates are set up with 21lb springs. First run boost was 17 to 18 lbs. I cant find the sheet, probably still in the car. Adjusted the controller and it was like 22lbs and I started having spark issues. I will have to find the dyno sheet before I make an accurate statement. I dont think the dyno was loading the tq converter like it would be on the street. Its hard to find out diffrently cause we keep getting massive amounts of rain here. The dyno operator felt I was giving up massive hp and wasting my time on the dyno with the non locking converter. I find it interesting that with the whipple, the turbo with the old cam, and the turbo with the new cam I hit a wall on hp at about the same HP level and the one thing that is consistantly part of the equation is the nonlocking converter. Trying to get my mind around a logical conclusion.

Ken
 
Waste gates are set up with 21lb springs. First run boost was 17 to 18 lbs. I cant find the sheet, probably still in the car. Adjusted the controller and it was like 22lbs and I started having spark issues. I will have to find the dyno sheet before I make an accurate statement. I dont think the dyno was loading the tq converter like it would be on the street. Its hard to find out diffrently cause we keep getting massive amounts of rain here. The dyno operator felt I was giving up massive hp and wasting my time on the dyno with the non locking converter. I find it interesting that with the whipple, the turbo with the old cam, and the turbo with the new cam I hit a wall on hp at about the same HP level and the one thing that is consistantly part of the equation is the nonlocking converter. Trying to get my mind around a logical conclusion.

Ken

You will figure it out Ken I know exactly how you feel unfortunately
 
A non locking converter does not eat up 100hp. On a properly tuned engine making back to back comparison runs using a converter that can be commanded locked and unlocked, the power difference is in the 15-20hp range. I could dig out plenty of dyno sheets to back that up but I'm not going to take the time.

It's not the converter. If you have spark blow out you can't tune and you sure as hell can't use the dyno sheets for anything other than toilet paper. Also, if the dyno can't load the engine then you are wasting your time.
 
A non locking converter does not eat up 100hp. On a properly tuned engine making back to back comparison runs using a converter that can be commanded locked and unlocked, the power difference is in the 15-20hp range. I could dig out plenty of dyno sheets to back that up but I'm not going to take the time.

It's not the converter. If you have spark blow out you can't tune and you sure as hell can't use the dyno sheets for anything other than toilet paper. Also, if the dyno can't load the engine then you are wasting your time.

Dave, this has been a big debate on the net for years on how the converter performs on a dyno. Weather it be a set amount of hp or a percentage. Despite your experience tuning on the dyno I still respectfully disagree. I have seen otherwise what a non locking converter can do. I have seen this on a dedicated 8th mile race car and big hp street/strip car.

I do not know a thing about Ken's converter in his car but I would assume it is tight for the power curve the blower made thus making Dave's statement true for the 15-20hp loss.
 
Dave, this has been a big debate on the net for years on how the converter performs on a dyno. Weather it be a set amount of hp or a percentage. Despite your experience tuning on the dyno I still respectfully disagree. I have seen otherwise what a non locking converter can do. I have seen this on a dedicated 8th mile race car and big hp street/strip car.

I do not know a thing about Ken's converter in his car but I would assume it is tight for the power curve the blower made thus making Dave's statement true for the 15-20hp loss.

Statements like this combined with the fact that Ken hasn't even bothered to post his before and after dyno sheets make me wonder why I bother.
 
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