© 2020 MOTORSPORT NETWORK. All rights reserved.
Sign up to receive latest updates for Ferrari News, Threads, and Classifieds
Discussion in 'Vintage (thru 365 GTC4)' started by ag512bbi, Dec 19, 2019.
Borrani catalog from a few years ago.
Does anyone know the differences between the 15 x 6.0 RW 3690 and the RW 3711, and also the 15 x 6.50 RW 3801 and the RW 3715?
The accuracy is very inaccurate. Maybe that'll fix it.
my preference would be
7.5 x 15 front with 215/70x15 michelin xwx tires
8 x 15 rear with 225/70x15
for a muscular look and use 3 eared knockoffs.
If you haven't done so already, please check that your spinners have enough thread engagement, ideally 4 turns before tightening.
The Daytona hubs were designed to be used with the Cromodora wheels which have a different length centre to those used on all the Borranis. The spinners supplied with the Cromodoras only go on a turn or two before tightening, which isn't safe. Special spinners were produced with an extended thread to be used for the conversion.
If you have the wrong ones you can probably get the correct ones from the US Borrani agents, but if not we can supply them.
email email@example.com website www.turrinowheels.com
Here's an example of what Mr. Tomkins ("246tasman") is referring to, the one on left with shallower tread depth is (U.S.-delivery, octagon) nut for center mount Cromodoras on 365 GTB/4s, the one on right with deeper thread depth is for Borranis on same application.
Photo copyright of TTR (me)
Image Unavailable, Please Login
To fix “very inaccurate"(?) may require more than just change in tire diameter/size.
Let me Clarify what I said/meant: My Speedo is very inaccurate. AT LEAST 10mph slower than it shows. I do feel that's a Speedo problem though (and not a bad thing to have compared to the other way of: Faster than it shows)
Do I understand your clarification correctly, the cars actual speed is “AT LEAST 10mph slower” than speedometer indicates ?
If yes and tires are close to OEM diameter/size, your speedometer and/or its drive pinion may require calibration/service.
IIRC from the Autocar magazine road test of the Daytona, the speedo read about 33mph at a true 30mph and 160mph at a true 150mph.
"IIRC from the Autocar magazine road test of the Daytona, the speedo read about 33mph at a true 30mph and 160mph at a true 150mph."
Most cars manufactured in past 50 or years tend to have a built-/designed-in +/-2 MPH "over-read" (i.e. indicating more than actual speed), but anything over or under 5 MPH is usually an tell-tale of inaccurate calibration.
OTOH, given Ferraris traditional tendencies to over-state performance stats, +/- 10 MPH "over-read" shouldn't surprise anyone.
Does the Daytona speedo run off the transmission or one of the wheels?
Transaxle, driven off the gear*-nut in front of the upper, i.e. output/pinion (to final drive) shaft.
*Dependent on final drive ratio (?).
Yes, I think your correct. It probably needs calibration. Just dont feel like having it out of service for a bit.
I really enjoy driving the car in this "cooler" weather
Are there 2 types of wide 15 x 7.5 inch RW 3808 rims?
I ask because 250 GTO 3869 has RW 3808 rims that do NOT have the raised circular rim inserts that the spokes insert into, whereas 250 GTO 4153 HAS the raised circular inserts that the spokes are inserted into.
I have a 365 GT 2+2 and was wondering if the deeper knock off be used on both mags and wires safely?
I've never tried deeper reach center mount nuts ("knock-offs") on Cromodora hubs, so can't say for sure whether they would work or perhaps bottom out before tightening.
Thanks for the response. I’m in the process of getting a set of cromodoras to put on my car when I have the wires rebuilt and was hoping to use the same knock-offs for both sets of wheels.
It might be worth to have proper depth set of "knock off" for each hub design or at least measure/test deep reach nuts carefully to make make sure they don't bottom out too early.
Thanks for the info. Trying to figure out what I need to do to have both types of wheels.
How would a 225/70x15 look on a rear 7.5x15 rim?
Sent from my iPad using FerrariChat.com mobile app
The sidewalls of a 225/70/VR15 won't look stretched out nearly enough on a 7.5 x 15 wheel for the rear. A 9 x 15 Cromodora from a carbureted BB 512 is the perfect wheel to combine with a 225/70/VR15. Or a 9 x 15 Borrani with the proper offset.
Ok , so I have (4) 7.5 X15 RW 4326 Borrani’s. When I get on the Borrani’s website they say stock rim is a 7.5 x 15 RW 4075.
I’m confused if they are both 7.5 x15 why are they different numbers?
Second if I have (4) 7.5 x 15 for my Daytona Conversion What tire size should I use front and back?
I understand probably the best would be 7.5 front and 8 on back?
What kind of Daytona Conversion do you have? Coupe to Spyder or 400i to Daytona body? See here and scroll down.
See list in post #51.
RW 4326 are for a 400 Automatic.
RW 4075 is for a 365 GT 2+2, 365 GTC4 and 365 GT4 2+2.
A Daytona would have RW 4300/RW 4301.