Has anyone used the 8/35 ring and pinion?

[mnez]

Planning to put an 8:35 ring and pinion in a 915 for track use, made by Albins. Does anyone have any experience/feedback on their product?

[chris_seven]

I have used several 8:35 Ring and Pinions but they have all been manufactured by Tandler in Germany and they are excellent and we have never had any problems.

There is a company in Belgium that usually has them in stock and I will try to find a link.

[mnez]

Well I've had the 8:35 in for a while now. So far so good. Nice and quiet. Lots more zip.

[winders]

Anyone looking for an 8:35 ring and pinion would be well served to look at the Guard Transmission 8:35 ring and pinion....

Scott

[MBEngineering]

Hi mnez
the Albins 8:35 CWP is OK, it has the setting on the pinion and the back lash on the crown wheel, so if you have the gearbox setting tools, it will be a strait diff set, I have fitted the Albins, GT and the Tandler CWP's, the Tandler and the Albins have setting on them, the GT will have to be set the old way with engineers blue, to take a pattern of it, also the 8:35 is a Klingelnberg cut and not the usual Gleason, so the contact pattern is different.

regards mike

[darrin]

mnez -- have an '86 and am considering the 8:35 -- If you stuck with the stock 915 gear rations, could you quantify rpms at speeds (i.e. what rpm do you see at 70mph in 5th)?

trying to get a sense of what I'll "give up" for the extra zip.

[will hung]

Originally Posted by darrin

mnez -- have an '86 and am considering the 8:35 -- If you stuck with the stock 915 gear rations, could you quantify rpms at speeds (i.e. what rpm do you see at 70mph in 5th)?

trying to get a sense of what I'll "give up" for the extra zip.

Try this excel tool. It will tell you everything you need to know.

http://www.instant-g.com/Data/GearChart915.xls

[darrin]

great tool!

Thx

[will hung]

Originally Posted by darrin

great tool!

Thx

It's beyond valuable. Before rebuilding my gearbox, I spent way more hours than I'd like to admit playing with ratios on that tool.

[mnez]

Originally Posted by darrin

mnez -- have an '86 and am considering the 8:35 -- If you stuck with the stock 915 gear rations, could you quantify rpms at speeds (i.e. what rpm do you see at 70mph in 5th)?

trying to get a sense of what I'll "give up" for the extra zip.

Darrin, it adds about 500 rpm in 5th at 70 mph. Roughly equivalent to using 15" wheels with the stock ratios. Gear charts/ratio tools can give you a more precise answer. So far I like it, but haven't done any long highway trips. Depends on the kind of driving you generally do, I guess.

Mike

[darrin]

Originally Posted by mnez

Darrin, it adds about 500 rpm in 5th at 70 mph. Roughly equivalent to using 15" wheels with the stock ratios. Gear charts/ratio tools can give you a more precise answer. So far I like it, but haven't done any long highway trips. Depends on the kind of driving you generally do, I guess.

Mike

Mike -- thanks for the follow-up, I pulled the gear chart that Will Hung posted and have a clearer understanding of the 5th gear rpms -- I use my 911 as a daily driver, 20 mile commute from downtown denver to a western suburb, and generally take my wife's touareg v8 on trips, so I see no real issue with an extra 500 rpm in 5th.

I've heard that first gear feels too "short" on 86's with 7:31 r&p swaps -- did you maintain existing ratios and, if so, do you see this as an issue with the 8:35?

So far, my uncracked 915 is still relatively "tight" at 150k, but have a feeling it's going to need to be rebuilt soon and I see an 8:35 as a much more robust alternative to a 7:31 (especially if I increase displacement . .. )

[Bill Verburg]

Originally Posted by darrin

mnez -- have an '86 and am considering the 8:35 -- If you stuck with the stock 915 gear rations, could you quantify rpms at speeds (i.e. what rpm do you see at 70mph in 5th)?

trying to get a sense of what I'll "give up" for the extra zip.

here's what it looks like stock and w/ 8:35

[darrin]

Thanks Bill!!!

[mnez]

Darrin, I have stock ratios. 1st is indeeed shorter, but it isn't an issue for me since 1st is only used to get the car moving from a stop. I never pull high rpms in 1st on the street, and 1st isn't used on the track. It pulls much better in 3rd, 4th, and 5th. I made the change primarily for better acceleration on track. The tracks I go to use 5th gear. It is not a daily driver - track and weekend car only.

The change was brought about by the failure of the pinion roller bearing, with resulting damage to the gear faces of the R&P, so I needed a new one anyway. The 8:35 made sense for me.

Bill, thanks for the great charts.

Mike

[mnez]

Well, I've had a full season on the new R & P, and it's working great. No issues at all.

[Matt Monson]

Since this thread was just linked today I feel I should mention that our 8:35 has depth measurements very clearly marked on the unit. No old school bluing required.

[Geneman]

Does anyone have a similar worksheet in ecel for a g50 (88) trans? I am putting in a 8.32 r/p and would like to run the numbers. Thanks frank rauscher@wistar.org

[Matt Monson]

Frank,
Search around rennlist a little bit. I think Bill has run the 5spd g50 numbers there before.

[Matt Monson]

Frank,
Not as informative as one of Bill's charts but here is CMS's version.
http://www.californiamotorsports.net/G5001%20with%20832.pdf
You can accomplish a lot on a smart phone sitting in an airport...

[Geneman]

Thanks matt yes airports suck! Thanks for your help excellent frank