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Discussion Starter · #1 ·
Had the new motor combo out for the first time this past weekend. Very happy. The rpm drop at each shift is 900. 7500 to 6600. Is that expected? New engine combo. Throwing 150+ more hp at it this year and the car is 20# heavier. LS Turbo making about 1150. 3420# car. T400 and a pro torque converter, which is the same combo from last year. I lost all my data logs from last year when the hard drive locked up, but I do not recall the rpm drop this drastic. Thoughts?
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Mine is dropping 8-900 depending on how much power I give it. Figure out what your slippage is at the stripe to go with it.
 

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Discussion Starter · #4 ·
Sounds about right. Did it ET and MPH better ?
Yes. We started out with last years tune that went 5.56-5.60, and with only fuel curve changes to make it happy, went 5.44. The cam is the same as last year. The crank, heads, intake, and injectors are all new, along with an S485 vs an S480. There was also an AR trim change in the turbo. The 80 was a 1.10 and the 85 is a 1.32.
 
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Did you change the transmission fluid ?

Maybe it was low on the last set up and it now has the proper amount .

I think 900 is about right for RPM drop .

Is it the same for 1st to 2nd and 2nd to 3rd ?

The 1st to 2nd should have a bigger drop than 2nd to 3rd . At least mine does . Maybe its more load on the 2nd to 3rd
 

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Discussion Starter · #8 ·
Did you change the transmission fluid ?

Maybe it was low on the last set up and it now has the proper amount .

I think 900 is about right for RPM drop .

Is it the same for 1st to 2nd and 2nd to 3rd ?

The 1st to 2nd should have a bigger drop than 2nd to 3rd . At least mine does . Maybe its more load on the 2nd to 3rd
Yes, Its 1000 on the 1-2, and about 900 ish on the 2-3. Same 9 1/2 liters I always run. The real issue is the puter for the car had a hard drive lock up over the winter. I had backed up my tunes fortunately, but lost all my datalogs, so I have nothing to reference off of anymore.
 

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Discussion Starter · #9 · (Edited)
Can we get a quick rundown of the new set up? Id love for my old steel to run like that!
Aluminum 5.3 block bored+.020 and unfilled. Callies CCW crank, Manley boost rods, wiseco pistons. TFS as cast 220 heads, BTR shaft rocker system, LJMS stg 2 turbo cam. < Same as last motor. Edelbrock pro flo intake. Deatschwerks 150 injectors. BW S485 turbo. John Bewely spec'd the combo. I kept last years cam, as it is awesome on the street, and he says it will make 1250. It will be all done at 1250. I'm ok with that number.
 
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The shape of the curve will tell you a lot. Some of the really good, new converter designs have a driveshaft trace that looks more like a good clutch than they do a converter driven trans. Protorque, Cameron's and a couple others are doing this now. I have seen a few logs that are hard to believe but I saw the car make the pass sooo its not smoke and mirrors, LOL. They flash really high, roll over as they grab the engine, only vary 250 - 500rpm at shift and go out the back at 1% or less slip on the really good examples. Most I have seen are 2-speed Turboglides. I have seen a customer's car that also has the same company's turboglide in it run within 50rpm of crank vs driveshaft speed. I believe they are manipulating the converter charge pressure similar to what a Bruno Drive can do to all but lock the converter. Whatever they are doing its not hurting the thrust bearing and its only a 302 main SBF so nowhere close to being a bulletproof thrust bearing design or size.
 
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ls1 s/s notch on 28s
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The shape of the curve will tell you a lot. Some of the really good, new converter designs have a driveshaft trace that looks more like a good clutch than they do a converter driven trans. Protorque, Cameron's and a couple others are doing this now. I have seen a few logs that are hard to believe but I saw the car make the pass sooo its not smoke and mirrors, LOL. They flash really high, roll over as they grab the engine, only vary 250 - 500rpm at shift and go out the back at 1% or less slip on the really good examples. Most I have seen are 2-speed Turboglides. I have seen a customer's car that also has the same company's turboglide in it run within 50rpm of crank vs driveshaft speed. I believe they are manipulating the converter charge pressure similar to what a Bruno Drive can do to all but lock the converter. Whatever they are doing its not hurting the thrust bearing and its only a 302 main SBF so nowhere close to being a bulletproof thrust bearing design or size.
Probably have 2 dump valves..seems to be the move the last couple yrs..alot of small tire no prep guys been going to them lately
 

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Discussion Starter · #14 ·
Here's the 5.30 pass
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The higher you rev it the harder the converter will grab also your boost is falling off at higher rpm so your not making as much power which will also couple the converter harder causing the bigger rpm drop on shifts

Next time out either try to get it to hold boost to 7500 or shift it earlier and it won’t drop as much
 

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Discussion Starter · #16 ·
I would think with the new 1.32 AR, vs the old 1.10 AR, it would make more power up top, than last years combo. No?
 

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I would think with the new 1.32 AR, vs the old 1.10 AR, it would make more power up top, than last years combo. No?
Only if it needed the extra flow there and was choking before. Depends, maybe the cam was limiting it before and the extra exhaust flow won’t help much without a bit more duration on the cam to match the extra rpm ot now turns. Sometimes you need to change 2-3 things to make the one change work the way it should.
 

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It most likely didn't drop that much rpm since you are shifting 500 higher, but I bet it dropped back to about the same rpm with both combos.
 

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I would think with the new 1.32 AR, vs the old 1.10 AR, it would make more power up top, than last years combo. No?
A/r is a measurement of length..the finally inlet size to the turbine is the same..if i could remeber the podcast id link it but it was wild bill or another turbo manufacturer that went into detail on it an how many companys measure it differently so theirs no set standard..it was either on real tuners,power an speed or hidden horse power podcast..i wish i new exactly but i listen to podcast all day at work.
 

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Have you tried different trans fluids? Hydraulic fluid we use can vary stall 300-400rpm just by dumping fluid at the track.
 
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