G.M. Performance Parts Duramax Diesel Top Dragster final prep for testing .

Prob. also not a fluke that Hughes told me that they now spec much larger pieces for the high powered cars than in recant past. He said for TD, TS, SC, etc... where in past we built more 7-9.5" now thier doing more 11-12" Like "Big Red" he said with thier big rpm and that huge stator we can damn near lock em up like a clutch. They have some new ideas for the automatic pro mods also.....just sayin'
 
stock600 said:
Prob. also not a fluke that Hughes told me that they now spec much larger pieces for the high powered cars than in recant past. He said for TD, TS, SC, etc... where in past we built more 7-9.5" now thier doing more 11-12" Like "Big Red" he said with thier big rpm and that huge stator we can damn near lock em up like a clutch. They have some new ideas for the automatic pro mods also.....just sayin'
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Sometimes it's not about what's better....it's about talking up what you were given. Call up Joe at Pro Torque...those guys have some cool stuff out nowadays.
Any experience I have with them on cars I work on are not sponsor deals...it's 100% out of pocket.
 
You also can not overlook that most sponsored parts have a level of tech support you never see as a consumer. Items that work OK can be fine tuned for a specific application to be top notch.
 
Looks awesome Greg,, I am looking forward to seeing the car in SEMA. I am planning on being there again this year!! Cant wait
 
stock600 said:
Besides the dr. p truck what else has it been in? Data may have shown other wise but it sounded like it sliped very bad in that truck down track, didnt even hear the gear changes. Again I hope it works great for you for sure, you have a better chance of doing so w/ a d max rather than a 12v. All 3 oem brands have and still use a 13" l/u convertor and when those guys loss thier clutches in the l/u thier back to a fluid coupling design, and from what most say they suffer greatly when thier gone. I proved to myself that the fc design can be made much more efficent in a low stall speed unit in a high torque 12v but soon as I loosened it up to spool larger turbos the efficency went out the window again even being 13". And when I say loosened it up I'm meaning anything past 3k for sure. Remember also how Scotts and John's cars sounded down track with a small converter and glide simular to the dr p truck; like they were hung against the governer and the engine didnt pull down at the shifts, this isnt taking anything away from them but only suggesting there was pleanty left in them If locked up.
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It’s not really slip, its stall. A torque convertor does just that multiplies torque. This convertor works really well covering up the lack of acceleration of a diesel in a light car. It locks up within 6% thru the traps. Coan makes some of the best convertors in the racing world.
As far as gear change, you should just see a slight change in tone of the motor.
 
a few pictures of how the rotating assembly lost 52 + lbs.

here are the rods , I've had these rods for 4+ year's

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The JE pistons and light weight pin.



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the crank is not somthing I can show


the fly wheel from Reactor , I've had it for 4+ years as well

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the Fluidamper race damper for Dmax


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On my comp convertors I use either Coan or A-1 they are the only ones in the country on 9000+ stall convertors. I have a over drive unit that is almost done that will over drive the convertor 50% and let me run 7 and 8 inch convertors
 
My sand rail weights 1752 and at 2000hp I had to step to a 10inch but I am blown alky and powerband is 100% different than a druramax

sent from my galaxy s3
 
The convertor is sized and matched to the power band of the motor. If I decide to run B/DA which is a Pro Stock 500 inch motor, it will use a 7 inch convertor and stall around 9200.

If you over drive the convertor you reduce the torque by that % as well. Dmax power at 5000 rpm’s with a 50 % over drive will be the same HP but 2/3’s the torque. This would be 1400 hp at 7500 rpms that is smack in the lower end of a 7 inch’s efficiently band.
To make a maximum effort convertor work you stall it in peak power. let the car come to the convertor
 
Overdriving the converter rpm is going to help alot, rpm plays a huge part in making one work well and getting it to be efficent. Get to the track and lets see where the numbers fall; your crank speed/pinion speed math wont lie. All my info was learned by me the expensive way on my dime; sure things could have been better but I did what I could on my own budget at the time. Hughes has some new stuff out since thier products didnt work for me at the time back in 08; and with the addition of now being able to fit a 12.5" unit I believe Hughes could get it done now witha low speed high torque 12v/glide.

With your rpm and abilty to make good power up there plus o/d converter speed I'm sure you will be in good shape, what low gear planet set did you go with. I was told the deeper gear sets wont hold any power ie. 1.96's 2.08 or the 2.18's you any experince with this first hand? Reid says as the sun gear gets smaller in dia. it looses strength and fails..cracking between the teeth and center bore. Shame because with my setup not having the o/d I ran a tall final gear and tire; a deeper low gear like the 2.18 looked killer on paper..... but he said no way it would hold even one 40# t-brake launch. He said the straight cut 1.80's will all day long.
 
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The 1.80 is the best gear for strength, but I would like a lot more 1st gear, they have a new 1.89 that required case machines to fit that is stronger then the old 1.89 and 1.90’s. I might consider going with a Bruno Liberty, then I could get a 2.60 to 2.75 low to move the mass. . I run a lot of rear gear as well, to make up for it, and it might run out of rpms before the traps, but there is no E T to be gained on that part of the track anyway. I also run a smaller tire that will grow
 
COMP461 said:
The 1.80 is the best gear for strength, but I would like a lot more 1st gear, they have a new 1.89 that required case machines to fit that is stronger then the old 1.89 and 1.90’s. I might consider going with a Bruno Liberty, then I could get a 2.60 to 2.75 low to move the mass. . I run a lot of rear gear as well, to make up for it, and it might run out of rpms before the traps, but there is no E T to be gained on that part of the track anyway. I also run a smaller tire that will grow
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Ya, I'll look into the 1.89's before I buy, Ive not heard of them before. My low in the 400 was 2.48 and it was a bit too deep forcing the 1-2 shift just before the 60' stripe which was ridiculous. 2nd was 1.48 and was a bit to tall; I'd prob. made that 1.48 work If I could had used it off the brake but we couldnt fiqure out how to do it at the time. Mike Woods told me he got his 80e to leave off the brake in 2nd though so he found something in the VB that we missed or overlooked at the time. Something right around 2.1 then 1.1 would work just perfect.

Also since the new release of the aftermarket Reid 400 case thats way over due, it looks like a 2 speed 400 is going to get popular. Heavy internals plus this would give me a 2.10 then 1.1. Humm
 
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nothing wrong with shifting that quick. it moves the mass. I used a 2.75 low in the Dr Perfromance truck .
a 2.10 THM400 is great , but I like the GearVendor overdrive with a Power Glide.
 
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