Trilogy8

I have an 87' 951 and I've read lots of different threads on this, but I'm still very new to these cars that I don't know if I have a problem or not. I know there is supposed to be a natural lag with these cars, but how much of a lag? What I experience is in the low gears, 1st and 2nd specifically, that I have to get this car up to 2500/3000 rpms before it moves an inch. On a slight incline yesterday I barely got moving, but again, once it kicks in it seems fine. Don't seem to have this issue in the higher gears. Am I facing something normal or is this some sort of vacuum line or turbo issue?

mtnman82

I'm sure other more knowledgeable members will chime in here too...

If I'm reading this correctly, you're saying there is no torque until 2500~3000 rpm - which is when boost will start to kick in and add torque.Is the car stock? Or are you saying boost doesn't kick in until 2500~3000 rpm?

Is the car stock? I've personally experienced aftermarket chips which behave like you describe.

While there may not be 'gobs' of torque, there should be plenty enough torque to get you moving up a slight incline, so what you describe sounds like something may be amiss. If you're used to driving a 6 or 8 cylinder car, especially one of the modern V8's, it's not going to feel like that until boost kicks in. In case you haven't come across it yet here on the forum - 1 bar on the dash (stock) boost gauge is atmospheric, beyond that is when you're building boost.

Trilogy8

If I’m at a traffic light and the light turns green, I give it gas in first gear and it’s not until that 2500 rpm mark where the car will start moving,,, period.

968to986

Yeah, that’s not turbo lag. My 87 pulls cleanly away from a stop with relatively little throttle. Maybe your clutch is worn out?

Trilogy8

I had the cylinders and cable replaced a few months ago. The gear box works normal and I have no issue shifting. It’s the initial liftoff.

Noahs944

Maybe the throttle body cable is too loose?

fwb42

"I had the cylinders and cable replaced a few months ago."
What cylinders? Has the timing been done correctly?

MAGK944

Curious what cable in your clutch did you change?

Also have you physically checked your clutch is in spec as per the manual?

You will feel a worn clutch during initial take off and especially on an incline like you say is happening, other gears/situations not so much if at all.

Trilogy8

The master and slave cylinder and the cable between them. System was bled. Original issue was the pedal getting stuck. Before and after I never had any issue with the shifting and takeoff. Seems like it started just all of a sudden and not gradual.

Car was going in for the timing belt tmrw actually. Not sure what I should do now.

Trilogy8

This issue also happens in reverse.

V2Rocket

is your parking brake stuck on?

should be able to take off from a stop light (on level ground) by feathering the clutch at idle speed, no throttle required.

that much rpm tells me you've got extra "resistance" to motion somehow and you're burning up the clutch.

Trilogy8

Parking brake is fine.

Trilogy8

I was supposed to be driving about an hour to bring it for the timing belt. Is this recommended to do at this point or bring somewhere closer for this issue? I have no idea why this would have started happening just out of nowhere.

mtnman82

As Spencer said, you should be able to take off from a stop on level ground by just feathering the clutch, no throttle.

First things that come to mind are something hanging up causing a significant amount of resistance/drag, engine power/torque is being affected, or clutch slipping.

Can you roll it on level ground in neutral with the parking brake off?

After you are moving, does the power seem normal or does it seem down on power? Especially under 2500 rpm?

After you're moving, when boost kicks in or at higher rpm can you tell if the clutch is slipping - rpm's go up but speed doesn't increase?

Trilogy8

Good questions, let me go try those things now and circle back. I’m really hoping this isn’t the clutch. I’d be a bit surprised if it were. What do the tests below tell you?