Hi there,
Sorry if this is not the way to do this.

I have a 1989 928S4, yesterday I was using it in the 1/8 mile track, when it goes out of 1st gear it shifts in 5000rpm, it doesnt reach redline. What could this be?.

And the other thing, I will like you to help me with this, How can I increase my car horsepower? It is serviced, well kept, all original bone stock. I readed 1000 threads, sites, all you may think. But you are the experts here.

Hope you can give me a hand! Thanks a lot!!!

 

Helmut, Willkommen.

Wo wohnst du/where are you located?

 

"I have a 1989 928S4, yesterday I was using it in the 1/8 mile track, when it goes out of 1st gear it shifts in 5000rpm, it doesnt reach redline. What could this be?."

I was going to ask... Automatic or 5 Speed Manual Trans please?
But now thinking it is an Auto and is up shifting to second and you want it to shift at Red Line, correct?

Place Shift lever in "2" and hold peddle to floor, it should shift at or near Red Line, you will need to make sure the "Kick-Down" switch is working. Sometime the carpet can get in the way or it could need adjustment.
Once it shifts into Second, then move the lever to "3" not "D".

Hope this is what you are asking.

Dave K

 

Welcome sir, using the info provided by Dave this is how you would test if the Bowden cable is properly adjusted.
you will need a 7 mm and 8 mm wrench set and some clear road where you can pull over to make adjustments.
If the trans wont go to redline then the cable is too loose so you only need to turn the cable in the ball end about 1/4 turn at a time then retest.

NOTE the throttle cable must be properly adjusted first,
Note if you tighten the throttle cable at the quadrant adjuster ,
then you will in effect be loosening the bowden cable,
the reverse is also true so you might consider loosening the throttle cable, before making Bowden cable adjustments

NOTE the throttle cable is the one that goes from the quadrant around the wheel, then onto the TPS ball connection.

To get more power from your engine,
Get an X pipe, this will give you about 25 more H.

Roger sells them, these pipes are MFGd from the boys at Motorsport in Utah.

 

Hallo leon speed!, I am located i South america.
Yes dave, I"ve been reading about the bowden cable, I also readed that some people glue some cents to the kickdown button.
At first, my pedal wasnt touching the button even when i loored it, then i adjusted the pedal and it was ok.
The car is automatic, and the cable that is nearest to the fender is a bit loose.
Sorry if I have some gramatical mistakes.
Dave, I did go in "2" and then "3", but in the best of cases it up shifts in 5200rpm.

And about the horsepower improvements, what would you say?

Thanks a lot for the quick answer

 

Now i went outside and checked the cables. Looking from left to right, the cable that is closest to the valve cover is very loose, the cable above it is wull adjusted, and the third is a bit loose, should they all be a bit tight?

 

Read this it should answer most of your questions

https://rennlist.com/forums/928-foru...ble+adjustment