Hi, just dealing with the classic sticky throttle problems on my 355 - going through all the usual fixes as we speak. I have read in several threads that there is an updated quadrant linkage for the throttle bodies. Can anyone tell me how you distinguish between the updated and non-updated quadrant? many thanks Mark
On my 1995 the bel crank has been modded to update it. Basically the bell crank angle is slightly changed so that there is less angle the curved part that holds the throttle cable is almost in line with the two mounting points. This pic should help. The one on the left is the old style. Image Unavailable, Please Login
Have not heard about this mod before. Was this mod installed on any 355 from the factory.....if so what year? For those that installed this....is this mod effective?
Early F355s had it, not sure what year model the change occurred. My car was modded at the Ferrari dealership the bell crank pulled apart and spot welded in place to mimic the updated version, a tech I know said this was common practice. It's a well known mod in the circle of techs with experience of the F355. For the record my F355 has no sticky throttle but I have driven a car with it and it's down right scary!
My 95 is an early car - looks like I have the old style... Image Unavailable, Please Login Image Unavailable, Please Login
Happy to help Dave. This is known as the quadrant. Your 95 one whilst super clean and looking great is the old style, you can mod that one as mine has been done, as the updated part isn't exactly cheap.
I am sure i read somewhere that the factory adopted the mod on production cars from 1997, but not sure when in that year. Can't even remember where i got that info. I think a lot of UK cars were updated early on in their life, while in the main service network. I spoke to one of the head Ferrari technicians down the garage, he does all the 355's that come through, he commented that he hasn't seen the old style on any UK cars for years.
Ferrari calls it a transmission lever and the rest of the world might generically call it a bell crank. Calling it a quadrant makes zero sense and is rather misleading.
You got that right For the last 4 years I've been trying to figure out WTF is this quadrant that people talk about
I agree and referred to it as the bell crank in my first post. Even the tech at the local Ferrari dealership referred to it as a quadrant not sure how this has eventuated. Do you happen to know when Ferrari updated this bell crank?
My prior 95 was the 15th to come to NA so it was a very early car. No records of this part being replaced and it did not have any sticking issues. P/N: 161826 says valid until Assy number 28137 P/N: 175234 says valid from Assy number 28138
Anyone know who could reliably mod the old ones to the new angle? It says welding is involved. Is this part all one piece (looks like it)? Does it have to be broken apart, the 2 "ears" rotated to the new position and re-welded?
Here is a picture of my modified one. It isn't pretty but looks to have been separated and re welded to the new position which changes the cam angle to mimic the updated part. Last I checked the updated part on Ricambi was around 600 USD so this must have been a mod done at the dealership without the cost of replacing the part. Image Unavailable, Please Login
The bell crank (OEM) is a welded assembly. Cutting it apart are re-welding would not be difficult I passed on an entire assembly for like $25.00 a year ago coz I just did not need it. Seems they go for around $300ish on ebay
This would be the way to go Dave. I had purchased new roller bearings for it and for the throttle pedal, one day will pick up a used updated bell crank and get it looking pretty like yours!
BUMP I have the old style bell crank and my pedal is very responsive. Can someone comment on the before and after with this upgrade?
If there is no jerkiness or sticking of your throttle pedal then you won’t notice any difference modifying it.
After driving a few more miles, I can't say I have any sticking or jerkiness, but on initial depression I can feel what I would call a flat spot. It is not much of a nuisance as I have gotten use to the feel and have learned how to drive without any noticeable issue,,,,,,,,BUT.....there are times when I can feel that flat spot and wonder is that what the newer style lever corrects?
Not sure about the flat spot you feel, but if you have the sticking throttle/jerky issue, you'd know it; that's what the updated quadrant is supposed to correct. (I bought one from Eurospares last fall, haven't gotten around to installing it yet).
