Trans Question

Cross the 1/8 in 2nd and the 1/4 in 3rd. :burnout:
I tried the 390s and the 325s and they did hook great, but screwed shift points all up.
THe shift points are computer controlled and NOT based on the valve body itself but the transducer, OD lockup and Pressure solonoid based on preprogrammed shift points by TPS and MPH and RPM. Valve bodies and shift kits will only adjust firmness between gear shifts and hold the gear a lil longer under normal driving.

With the 390 DRs, the rear wheels are turning faster than the fronts. The data coming from the ABS sensors (in this case) isn't helping the transmission to decide what gear it should be in.
Talk to your tuner.
 
My next phase is traction. I have Calvert traction bars from Tony I have not put on yet. I want to get a cam to record stock suspension twist or movement. Then add the calvert bars and record again. Then try the sway bar with traction bars and see how much better it gets. It cant get worse than stock.
 
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My next phase is traction. I have Calvert traction bars for Tony I have not put on yet. I want to get a cam to record stock suspension twist or movement. Then add the calvert bars and record again. Then try the sway bar with traction bars and see how much better it gets. It cant get worse than stock.

Im loving my caltracs....world of a difference when under WOT now....but i had a leaf spring removed so i had horrible axle wrap under WOT
 
I'm having an issue with hitting the rev limiter just as I'm going through the traps in the 1/4. I'm also running the 390's. Probably not good to be hitting the rev limiter under full boost. Is this just a matter of having Torrie raise the rev limiter a bit?
 
;)
I'm having an issue with hitting the rev limiter just as I'm going through the traps in the 1/4. I'm also running the 390's. Probably not good to be hitting the rev limiter under full boost. Is this just a matter of having Torrie raise the rev limiter a bit?

I would say you need the shft point bumped a bit and not so much the rev limiter. If you are already around 57-6000k RPM then it is the shift point needing changed. Usually by MPH if not mistaken.
 
I'm having an issue with hitting the rev limiter just as I'm going through the traps in the 1/4. I'm also running the 390's. Probably not good to be hitting the rev limiter under full boost. Is this just a matter of having Torrie raise the rev limiter a bit?

you need to run a taller tire probably santeen, but actually you need to look at your dyno graph, see where the hp is peaking, then we need to get your shift point to shift about 200 rpms before peak hp
 
you need to run a taller tire probably santeen, but actually you need to look at your dyno graph, see where the hp is peaking, then we need to get your shift point to shift about 200 rpms before peak hp

;)

I would say you need the shft point bumped a bit and not so much the rev limiter. If you are already around 57-6000k RPM then it is the shift point needing changed. Usually by MPH if not mistaken.

I'm already in third when I go through the traps, so I dont think I want it shift into fourth. Our trucks fall flat on there ass when they shift into fourth. But, I definitely dont want it hitting the rev limiter under full boost. And I would love a taller tire, but I doint want to go with slicks and I havent found a taller DR.
 
As for peak power in the dyno chart. it was still pulling by the time it hit the rev limiter, which looks like around 6000 rpm. I'll try and post it now.
PaxtonDynoTune006.jpg
 
As for peak power in the dyno chart. it was still pulling by the time it hit the rev limiter, which looks like around 6000 rpm. I'll try and post it now.
PaxtonDynoTune006.jpg

then honestly I would suggest changing the limiter, but I would also change out the pushrods at least for safety, and really the valve springs, but at least the push rods, raise it to about 6300 and with pushrods you should be ok
 
It would be nice if there was a taller DR. I also have the 390s. I missed out on buying slicks here a couple months ago.
 
Are you banging the limiter in 3rd? Do you have it in tow/haul mode so that it doesn't shift into 4th? If so, you could either let it do the 3-4 shift or you could have Torrie raise the limiter to 6200 so that you could go through in 3rd.

With power still rising and torque falling, you really want to stay in 3rd for the best time.
 
From all my years racing, and building motors, I was tought to shift 2-300 RPM PAST where PEAK HP and TORQUE cross. So about 5800 is where you should shift to keep power producing into the next gear. I wouldn't change gearing since we need the lower gears to get our big asses off the line, but I would go for a taller tire. I never cared how the 390s looked and the 325s were ridiculous short. ARRESTMERED has a set of slicks that were the perfect size, but again, were SLICKS!
You are correct, you don't want to go into OD at all, so tire height will be your savior.
I WOULD NOT SPIN THE MOTOR PAST 6K RPM even with springs and pushrods. It's the bottom end that can't take the revs as well!;)
 
From all my years racing, and building motors, I was tought to shift 2-300 RPM PAST where PEAK HP and TORQUE cross. So about 5800 is where you should shift to keep power producing into the next gear. I wouldn't change gearing since we need the lower gears to get our big asses off the line, but I would go for a taller tire. I never cared how the 390s looked and the 325s were ridiculous short. ARRESTMERED has a set of slicks that were the perfect size, but again, were SLICKS!
You are correct, you don't want to go into OD at all, so tire height will be your savior.
I WOULD NOT SPIN THE MOTOR PAST 6K RPM even with springs and pushrods. It's the bottom end that can't take the revs as well!;)

its like setting a shift light, if you set shift a couple hundred rpms before the actual shift, by the time the shift has occured, you are at that determined shift point, thus if you set it at 6000 most of th etime by the time the shift has occured you are a couple rpms later than 6000
and the bottom end will be fine going past 6000 not under nos, the valve train tho is not designed for it
 
then honestly I would suggest changing the limiter, but I would also change out the pushrods at least for safety, and really the valve springs, but at least the push rods, raise it to about 6300 and with pushrods you should be ok

I'll just wait until my engine build. ;) No sense in going through all that now.
 
Are you banging the limiter in 3rd? Do you have it in tow/haul mode so that it doesn't shift into 4th? If so, you could either let it do the 3-4 shift or you could have Torrie raise the limiter to 6200 so that you could go through in 3rd.

With power still rising and torque falling, you really want to stay in 3rd for the best time.

Yup, Tow/Haul mode, so it doesn't shift into fourth.
 
I'll just wait until my engine build. ;) No sense in going through all that now.

there isnt at all, but push rods you could do easily if wanted, have torrrie raise up your limit a couple hundred, see if that helps for now, you"ll be fine, besides, you have a spare.....;)
 
Be careful buzzing these engines too high fellas-

If the lifters turn inside of the stock lifter holsters, it'll wipe the cam out in a heartbeat.
 

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