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I'm having an issue shitlfting from 1st to 2nd when at the drag strip. The linkage isn't bent or anything and I have the act 6 puck sprung clutch. It's like when I shift it feels like it goes in but doesn't engage. First thought was bad synchro, you guys have any other suggestions?
a bad syncro will grind going in. does it feel like it goes in but pop back out when you let the clutch out? or does it just not go in? how does it work under normal driving conditions?
maybe try adjusting the shift cable, make sure the shifter the cable travels far enough to get it all the way into second gear.
well it doesnt grind going in nor does it pop back out. Just doesnt go in, could be driver error who knows. Its perfect under normal driving conditions
Seeing as you said this only happens at the strip, I would assume it's when you're doing some extreme shifting ( like > 6500 ). There is actually a limit to how fast a "conventional" synchro can perform it's job. And during the 1-2 shift is when the most synchronizing has to take place in the shortest ammount of time. Just think of how many times you've seen one of your buddies grind going into 2nd, especially when trying to show off. You could just be exceeding their limits with your current demands at the track, even if you're still doing your job (shifting):drivin:perfectly. I would assume your car is equipped with the standard synchro (Lynholm if I'm not butchering the name too bad), which kind of screw or twist to engage. There are advanced versions of this style and also another seperate style of synchro called "Dog Ring Engagement" that uses lugs that lock together almost instantaniously instead of twisting. It's actually a rather simple and powerfull design believe it or not. The tradeoff is that they are louder and not smooth enough for the average daily wuss (commuter) I can't guarentee theese would be available for your gearbox, as I've only seen them in Mustangs. (T-5 or T-56 tranny)
there is very limited aftermarket for the f35 transaxle. aside from cryo treated stock parts for improved strength, the only upgrade is the quaife close ratio 6 speed conversion. the f35 does fine with high rpm, never heard of shifting issues with people running 400+hp shifting at 8000rpm. the f35 itself is pretty good overall.
i started thinking about this more and its possible its your clutch. bulley clutches had problems with the cobalt ss clutch they made, specifically the 6 puck discs. basicly, they were far too heavy and at high rpm carried too much inertia and you were unable to shift till the rpm came down. from what ive heard they discontinued the 6 puck because of this. i have no experience with the act clutch, but im wondering if your experiencing the same thing.
well i found a few upgraded parts on ZZP.. thinking of going with these first since they are cheaper than doing transmission work.
Adjustable Clutch Rob: http://zzperformance.com/cobalt_ion/...1096&catid=188
Revised Shifter Bracket: http://zzperformance.com/cobalt_ion/...1259&catid=188
think these could help me out?
first off, how is your clutch release height? where does the pedal grab, near the floor, near the dash, or somewhere in the middle? also, how is the freeplay at the top of the pedal? the clutch should move about a 1/2" at the top of the travel with no pressure. when adjusting the pushrod length on a hydraulic system you are supposed to adjust the freeplay at the top of the pedal, not the engagement point. adjusting the engagement point so its higher will lead to pressure on the clutch from the release bearing, reducing the holding power and acting like a driver thats riding the clutch. i have yet to find a reason to put an adjustable pushrod on a cobalt.
as for the shifter bracket, just put one on my car. it makes the shifter feel more positive. its actually the stock bracket for the 2008+ turbo cobalt, so you can walk into a gm dealer and buy it. i actually got it cheaper from crate engine depot, just e-mail them asking for it. was roughly $20 from them.
It grabs about mid way, probably a little more to the top. There isn't a whole lot of free play when fully released. I'll have to check ced for the bracket. Never knew the LNF's came stock with them, must be nice lol. I guess thats why alexs feels a lot better than mine haha
there are a lot of little things that gm changed between lsj/lnf, and lots of them swap over. this happens to be one of them.
if the clutch grabs mid height an adjustable pushrod isnt going to help, save your money.
I'll prob just try out that bracket first. Who knows could be a cheap $20 fix
I have the ACT sprung street disc and it works great. Wanting to swap over to the 6 puck. Have you had a chance to install that bracket to see if that helps? Im thinking that the shift is either too fast or your shift linkage isnt as tight as it could be, you can adjust it slightly on the bottom of your shifter.
l8r,
PD
i already changed his linkages looks like hes got a trashed synchro the bracket is good hes just gonna drive it out till later
You know what they say, "If it walks like a duck and quacks like a duck....."
Do you have a torque dampener installed, or any solid motor/trans mounts?
I noticed 2nd gear misses when the motor would bounce around all sloppy during shifts. Improving mount stiffness took that condition away thankfully, and also minimally reduced wheel hop too.
(Tension pin aka Roll pin) Its a possibility, but i still see the synchros or a bad pressure plate or friction disc causing it. Is there any fluid leaking? OP drive the car without doing it hard just take it to 6 k slowly, and try shifting into 2nd, 3rd. if it engages id say synchros are still a possibility but the clutch is a possibility as well.
I have a torque dampener installed and about to install trans mount and the linkage bracket here in a few weeks hopefully. Everyday driving is great, have had no issues even taking it up to high rpms and casually shifting. I'll have to see what happens with the added hardware and a trip to the track. Only problem with that is the track around here has been shut down :(