hey guys...my cars always been like this im just curious....my dash shakes alot at about 80-85...my new tires helped a lil bit but not a whole lot....and my buddy has an 89 gti with suspension work and the same thing happens....

 

Try changing your u-joints. If that does not help then you will need to change the driveshaft to an aluminum one. If you have an aluminum one right now it is probably just the u-joints or it could also be out of balance due to looosing a weight but very unlikely.It could also be the whees and tires out of balance but not likely either since you stated you just replaced them recently. Check those u-joints.

 

ya i figured that ok thanks....but what about my buddies gti thats front wheel drive...i dont know 2 much about front wheel drive cars

 

basically the same thing- CV joints from hard acceleration and cornering loads.

 

nice info thanx

i need an opinion if u dont mind or anyone else who wants to chime in

what do u think is better...aluminum driveshafts or carbonfibre drive shafts

i hear aluminum isnt to safe

 

Well since you are asking a person that happens to own two different full carbon fiber driveshafts on two different vehicle I currently own and use daily, I will say by far the CF is far superior to the aluminum ones.However, if the aluminum is working for you and you are not into reducing rotation mass & reducing unsprung weight and the high dollar that takes to do that then the aluminum is very strong for any high hp streetable third gen. Where the weakness come in is the u-joint size, not the shaft material and diameter of the aluminum factory units. The 1310's are weak and should be replaced in appropriate intevals if vibrations start occuring- this will help prevent launching a shaft out of the car. I have never seen an aluminum shaft bend or break from HP, but I have personally had u-joints go to hell in a big way and cost me $6000 in damage under my Vette years ago from a half shaft cutting loose on me- and it was a 1350 u-joint on 4" aluminum spicer halfshafts. I still reused those same halfshafts with new u-joint installed when I put it back together- its been fine still after all these years but I do frequently change U-joint much more often nowadays or do not lay down the HP if they have been old and sitting for a good period of time (this car lays down 540hp)
Back to my CF shafts- My truck CF shaft is 4" round and SIX FEET LONG and was custom made with 1350 end yokes through ACPT. This whole shaft weighs an astonishing 7.8lbs. I tried a steel unit in this truck at a smaller dia 3" and it was stilll very eavy at the trans yoke causing severe vibration problems (that shaft weighs 24.5 lbs ). Smooth as glass all the way up to 140mph- I anit gonna go no faster in a truck.

 

Carbon fiber has no real streetable lifetime, it simply wears out to fast.
It has no equal until its comprimised but when it begins to unravel or the metal to CF adhesion fails, look out

Alum it perfectly safe, they wouldnt have used it in all those top end 4th gens if it wasnt

If you suspect your DS to be out of balance then using a quality replacement, rather than a refit from a JY car would be your best bet

A quality balanced steel DS is just as smooth as a high dollar CF or alum DS

The only reason you would change to a lighter one is for clearance tolorances or weight savings for racing applications

 

wow thats alot of good imput...ok im gonna replace the u-joints and if that dosent help im gonna get an alum driveshaft

 

You are so wrong in so many ways- I am not going to even waste my breathe with you other than to say I have show nurmerous documentation on these boards already that factually proves you WRONG.
Use your search button, It will help you learn the true facts, not the myths

 

i thought that sounded weird cuz i always read that carbon fibre was better cuz the aluminum dosent have the same level of durability

looks like i got more research ahead of me

 

For you I will help- I just can't stand when naive others try to come into here and act like professionals on a part they have never owned but just read hearsay and bash it.CF has fantastic damper qualities. It does not transfer noise or vibration. Aluminum still does. What make aluminum better than steel is its weight reduction on the bearing- as for rotation mass, alum and steel are pretty much identical because even though the aluminum is less weight, they are a large dia than the steel shafts so that less weight is gained back in polar weight on rotation- THIS IS WHY NOONE SEES ANY PERFORMANCE GAIN BY GOING TO ALUM PEOPLE. CF has the strength and rotation lightness that far exceeds aluminum- You do see noticible gains with CF.It is very light so it loads less weight onto the tailshaft bearing on the trans as it spins. 20 years ago, GM made a few factory aluminum shafts that CAME FROM THE FATORY WITH AN ADDITIONAL CF SLEEVE WRAPPING- GM had to add CF to them because in this peticular application the alum was not enough and the cf wrapping helps eliminate vibration transfer much better that just the alum alone. The CF was thin and only a coat and was merely glued on top at the ends of a 6ft span. I owned one of these for 14 years until I rubbed it against the frame xmember from an airbag going out with a load in the back of the truck. The CF did dislodge and slipped from the impact and under inpection you can see that the alum to CF bond spots were just dabs of glue onto none scuffed areas of aluminum tube surface. The special ACPT ends used in full CF shafts have specially machined ends that are more or less explained as kindoff corragated and the glue areas are about 20 times larger than what was done on the factory 'coated' shaft from GM. The aerospace glues they use are the same stuff they are bonding the F117 stealth jets to there internal aluminum structure points. They use CF on the outside due to its radar absorbing properties- but we are getting of track here.A large blow from a large hammer from the side will 'broom' these CF shafts- its a built in safety feature. They do NOT cross weave the CF direction for this very built in safety feature in case one comes flying ou tof there. The fiber is only layed in wrapped direction in a slight weave crisscross pattern for long strength and twist strength, but will not hold very strong lateral support purposely- If you have something hitting yours from the side that hard then you are either offroad racing or you are in an accident- or a u-joint snapped and it came flying out of there.They are extremely safe and extremely durable FOR DAILY STREET USE- I have two daily drivers of my 5 vehicles and both my daily drivers have CF shafts in them.If steel is just as smooth- then tell me why I have 2 broken tailshaft housings in a years time from a custom made 4130 shaft I had in there for a year and had it out 3 TIMES checking the balance. It was just reacting its critical speed for the length and weight of it and could not hold a candle to CF, neither copuld the aluminum one hence why even GM warpped an alum one wioth CF from the factory almost 2 decades ago with inferior glues and technology of the time and it still worked great for 14 years until I screwed it up.
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If you are interested in a CF shaft, FRRAX.com is having a group purchase right now on them that you need to act pretty quickly on.

 

thank u very much hpe u just saved me quite a bit of guess work

u seem to have alot of knowledge on this...u should create a sticky thread cuz this is some good info i think everyone could use

 

Your welcome.You can see some good info pics and the actual shafts from both cars on this link page. The one you can see attached to the tranny is the F-body standard ACPT unit at 4lbs. You can also see if you look very closely it has CF 'weave' supplied from a different manufacturer than the second longer pictured below that I list for my truck application at 6 feet long and 7.8lbs .(You can tell the other one is that long via comparison nest to the 26" dia weel and tire on the Camaro parked next to it- But that one is the truck custom 4" round shaft with 1350 yokes)The first pic Camao shaft has a yellowish crosshatch weave fiber and the secoind one has a bluish gray croshatch weave fiber that is harder to see in the pic. They are the same grade and quality fiber weave, just from two dofferent suppliers and both final product driveshafts were composite formed and assembled at ACPT.http://www.cardomain.com/ride/518752/2

 

very nice