Guys

The car is making ~600/500

Clutch is an ACT HDG6

I took it to the track today, and didnt manage a single 'good' 3rd to 4th shift.

I am shifting at ~8k - I do not experience any issues on the 1>2, or 2>3 shift.......I even tried no-lift-shifting w/out any issues at all....

The car went 11.6@128 with a **** 2.0 60ft and having to convince the trans into 4th.

Is this an issue with the clutch, or is this possibly something with the trans? When it locks out, the trans does not grind or anything, and street driving the trans shifts perfect in all gears.......

All of the other threads I've read about the lockout, are only in regards to high-rpm....not gear specific.

Thanks in advance

 

its the act clutch locking you out of 4th. act has lock out problems.

 

Can someone explain what dynamic is changing to make 4th only the problem issue?

I can understand I may be putting a little more hp/tq down to the wheels due to the load increasing from 3rd to 4th, but RPM's arent a variable here, and I'm not sure what else is going to have any affect on the clutch wanting to disengage......aside from maybe some deflection in the engine/trans/t-case due to increased load

 

yea i got the act one as well and i get bad lock out but it just doesnt happen in 4th for me. Ive heard that the ACT clutch has a bad rep for doing high rpm lockout thats why when i get my transmission rebuilt here in the next month im probably going to go with the clutchmatsers twin disk or just a more higher grade single. since illalmost be reaching my power goal of 500whp.

 

[QUOTE=daishi77;8586731]i get bad lock out but it just doesnt happen in 4th for me. Ive heard that the ACT clutch has a bad rep for doing high rpm lockout [QUOTE]

This is the problem I have, in understanding ALL of this....


Whats the difference between 8,000rpm in 1st, and 8,000rpm in 2nd?

If it was just a 'high rpm' lockout, you would see it in EVERY gear.....

Thats the issue im trying to understand

 

so I've gathered more info

It seems the weight of the disc, coupled with the intertia induced by high rpms.......causes an issue of disengagment.

The reason the process isnt apparent in 1st, 2nd, or 3rd is that those gears have multiple synchros. 1st and 2nd having 3, and 3rd gear having two synchros. 4th gear only has 1 synchro so its ability to slow the shaft down fast, is greatly reduced, compared to the proceeding gears.