355 Ferrari F355 Challenge Steering rack

He put in a real challenge rack.

 

Did he modify his suspension as well?

 

To improve the steering?

 

Found this "The Fiorano Handling Pack option for the F355 which consisted of (amongst other bits) a race ecu, lowered, stiffer springs, thicker roll bars, quicker steering rack, cross drilled discs all round complemented with harder pads and red calipers."

 

Stiffer springs and challenge/fhp roll bars as far as I can tell.

 

Here's a video of Jeff Segal's car, and modifications he made, on track at the Monticello Motor Club...

 

Are the internals of a RHD and LHD steering rack different aside from being placed on opposite sides?

 

What do you want to improve::
a) make the steering lighter at the wheel straight line
b) make the steering heavier at the wheel straight line
c) faster turn in
d) more stability at turn in
e) more stability at track out
????

{Hint: the above are all adjusted with caster, camber and toe; sometimes in conjunction with ride heights.}

 

So are there any leads on a challenge rack or updated rack to reduce the lock to lock?

 

No. But I did find a RHD challenge rack. Once it arrives, we’ll have to take it apart to analyze the differences.

 

Looking forward to hearing updates.

 

Also… just to confirm specs, there have been old posts indicating the FHP/Challenge steering rack is 2.5 turns lock to lock. We’ve measured on multiple cars and it is 2.75 turns lock to lock. Standard is 3.25 turns.

 

For comparison, a stock 993 rack is 2.47 lock to lock. I am curious if anyone has explored other means of sharpening up the 355's dull steering feel. On my 993 I installed poly rack mount bushings and solid inner tie rods, and it made a genuinely noticeable improvement. There's no comparable inner tie rod on a 355 but there are two rack mount bushings. Anyone reproduced them in a stiffer material? And yeah, 3.25 turns seems like a lot....

 

Any further thoughts on utilizing this?

https://www.speedingparts.com/p/interior-exterior/interior/racing-steering-wheel/steeringrack-quickener/qsp-steering-rack-quickener-12.html

 

That looks interesting, but you'd need a taller ratio, 1:2 gives a lock to lock of 1.6, which is way too fast. Something around 2.5 is the sweet spot.

 

If I recall correctly, challenge cars might have “white” rack bushings, which would be hard. I’ll have to double-check on that. Energy Suspension might have had something as well. We just need sizes to know who offers what.

 

Not as good as my 993 steering, but a 340mm steering wheel helps a lot on my F355.

 

A few more points I'd like to make. It is said a steering rack job and pump install it best done during an engine out. So if this is something you really want, it is best to have parts kept aside when that time comes. All I know is, I won't be doing an engine out service until I have a quick rack and pump ready to go. There's no way I'm missing out on that opportunity.

 

https://www.a4h-tech.com/en/qsp-steering-rack-shortener-1-1-5-universal

This would make it approx 2.17, correct?

 

Challenge rack bushes are made of solid white delrin instead of the brown rubber in standard cars.

 

What are you doing with it afterwards Do you have a RHD you can fit it to?

 

Probably go on BaT to the highest bidder . LHD challenge racks are unicorns. RHD challenge racks are unicorns of unicorns.

 

Speaking of RHD, how many RHD owners are dead serious about a quick steering rack here? I'm not talking about iffy's. It's now or never.

 

The whole rack or parts thereof? And if parts, would we have to send our standard racks to the USA for conversion? I guess this depends on what you find.

And what other parts are essential? New pump? New reservoir? (Sorry, haven't been watching this thread until now).

https://www.eurospares.co.uk/Ferrari/355/355_Challenge_(1999)/PartDiagrams/016/ABS%20and%20Power-Steering

I wouldn't be willing to send my rack to the USA for some kind of conversion, so it would have to be a kit.

To show my enthusiasm/optimism, I just ordered a new Challenge pump.

 

I wouldn't go that far yet .

I'd prefer not to be responsible to putting together a whole steering rack. That's not my thing, although I will need to go through the process for myself. I'm mainly getting a feeler for who's interested in the internals (rack & pinion in quick specs) so one can go build his own rack. Any company going to build the rack and pinion is going to want a batch made. Highly doubt they'll do one offs. I'm trying to get a feeler for how many in LHD and how many in RHD. I think a batch of 10 would be enticing enough. So a batch would need to be made so I can have one (or two) sets for myself.

On a side note, I think it is best one buy a used rack and have it built on the side, so it is ready for installation. That's my plan. I think it could even be a bent rack since the internals would be swapped out.


This really is a now or never thing as once I have my sets, there wouldn't be much motivation for me to get more batches made.