LS1-450

iTrader: (33)

@ high RPM's, does it take you a good shove to get her in gear? Have been told that it could be clutch dissengagement dynamics @ high RPM, but I don't think so. Trans is newly rebuilt & the same condition existed during the life of the "before rebuild" tranmission & different clutch. Also, I have played around w/engagement/dissengagement by adjusting the clutch master. All that happened was that the clutch then slipped & the modification did not improve the getting into gear stuff.

Was also told that it's not the shifter, Pro 5.0. I agree & don't how how a shifter could cause this issue. Wanted to note it in case someone has different information.

Does not grind into gear, it simply takes a spirited shove to get her in, notchy. GM/Viper T56.

Comments please

BALLSS

FWIW I bought a new t56 from D&D with the typical upgrades but not the "viper" tail shaft. No shift issues at 6500 RPM...mine is LT1 with "pull" type clutch.

I found their CS good so give them a call for what I would regard as a very qualified source of info.

thesource

iTrader: (60)

D&D builds the exact same units as any other shop that specializes in T56 or Tremec built units. I would agree with them that its probably clutch related. Did you install a new pilot bearing? What fluid are you using? Are all the factory dowel pins in place (2 in the back of the block and two in the front plate of the transmission)? What do the holes where the dowel pins fit into the bellhousing look like?

LS1-450

iTrader: (33)

Trans has no front plate. Dowels are in place. Holes looked OK when I re-installed it. Redline D4 transmission fluid. New pilot bearing installed. I believe the clutch & hydraulics are fine. I can look through a small hole I drilled into the bell housing & the throwout bearing is seated onto the fingers & compresses the fingers to what looks to be close to 0.5". Spec says 0.315" is enough.


What about the trans mount? There is no torque arm. There's a poly mount (block) between the trans support & the trans. Trans is held to the frame under the stock tail location.

thesource

iTrader: (60)

The way its mounted shouldn't be an issue. When you say it has no front plate??? I am speaking of the plate on the front of the transmission. It has two dowels on it. How do the holes look where the dowels fit into that side of the bellhousing?

Those adjustable master cylinders can be a pain to adjust. Usually if they transmission does not grind in 1st or reverse and the clutch does not slip, they are adjusted correctly.

When you say high rpms, how high are you referring to?

SPEEDYws6

iTrader: (9)

See if you have any creep while in 1st gear and clutch pedal to the floor on level ground, rev the engine to about 5k. If the car moves forward the clutch is not disengaging fully.

85MikeTPI

iTrader: (9)

Who rebuilt it and what was replaced/upgraded in it?

I just opened up a GM/Viper D&D trans. Had plastic fork pads (that failed and caused $1000 in damage), and stock stamped keys in it..

LS1-450

iTrader: (33)

Thanks for the comments

Wish I new how to reply to all three of you @ once, but don't know how to combine the messages. Anyway, I understand what you meant by "plate". My transmission has no front plate. The bell housing bolts right up to the back of the block. Dowels fit snug w/ no signs of ovaling.

I believe that the clutch & master are very well adjusted. Just 10 minutes ago looked @ the slave cylinder travel again & it's a good 0.5+ inches & protrudes well into the PP. Am gonna check for creep as noted by SPEEDY for further confirmation.

High RPMS, possibly from say 5,200 to 6,400 RPM.

General comment: I only noted DD Performance in case someone knew of a specific event related to it. D&D are great people & have bent over backwards to help me in the past. Am not suggesting anything negative when relating to D&D. Just posting all of the info about the transmission. Personally, in the future, I will only buy from & have them work on my transmission. They are only 3 hours away from here.

LS1-450

iTrader: (33)

Thank-you, I will try that.

LS1-450

iTrader: (33)

Funny, you should ask. A local "expert" bought the parts directly from D&D & then proceeded to order & install a Ford input shaft (not GM). I mounted it & stuck the input shaft deep into the pilot bearing which caused the trans to not dissengage. Long story short, D&D made sure that the local installed the correct shaft the second time. D&D also confirmed the parts used on the rebuild. This is what I reffer to when stating that in the future, will make the drive directly to D&D so that it's done correctly the first time.

Thanks for the suggestion. I am sure that the internals are not the issue.

LS1-450

iTrader: (33)

Did creep test. No creep, but, clutch engages (car creeps) with pedal just off the floor. Am sure that @ high RPMs, the pedal is not pushed in that far. So, this may be the issue. Will take her for a ride tomorrow & see if putting the pedal to the floor corrects the issue.

squale iii

ls1 in a miata?? that's cool as ****!

LS1-450

iTrader: (33)

^^^ Thanks



Guys, I've decided to make a run to Summit tomorrow & pick up a 0.875" master to replace my 0.75" master (Wilwood). This will allow the pedal to be further off the floor, thus eliminating the clutch & clutch hydraulics as an issue. Will post the results.

Thanks for all of the feedback & we'll see what happens.

LS1-450

iTrader: (33)

Follow up:

Got the 7/8" Wilwood adjustabe, got her installed & bled (OMG, I hate bleeding hydraulics). Just got back from testing. Clutch engages much higher in the pedal & is smooth like butter (comapred to where it was) @ high RPM shifts. So, the issue was indeed clutch dissengagement & the 3/4" master just wasn't large enough to move the proper amount of fluid.

Thanks again guys.....I/m a happy

BTW, called D&D back to let them know that their assesment (clutch related) was correct as well.