Changing Final Drive ratio??
06-26-2003, 01:14 PM
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Changing Final Drive ratio??
I just got the 4.11 ring and pinion from Powerhaus, I was just wondering if any of you guys out there have tried messing around with the FDR? If so what should I expect (performance wise)? its an 86 na... If nobody has ever done it I'll keep you guys posted on how it turns out.
06-26-2003, 01:38 PM
#5
Three Wheelin'
Do they have Audi part numbers on them? I think that ratio is used on the 4000 Quattro, among others. Be interesting to know if they fit.
Some 951 guys are putting S2 trannys in for better acceleration, so why not gear down an NA? It would work well with cam/headers/open exhaust and an increased rev limiter to give more power up top. I am not sure that re&re'ing your tranny would be worth it, however, for the relatively minor gearing change you will get going from 3.89:1 to 4.11:1.
Some 951 guys are putting S2 trannys in for better acceleration, so why not gear down an NA? It would work well with cam/headers/open exhaust and an increased rev limiter to give more power up top. I am not sure that re&re'ing your tranny would be worth it, however, for the relatively minor gearing change you will get going from 3.89:1 to 4.11:1.
06-26-2003, 01:39 PM
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I dont know how quick it is because its still in the shop right now but i'll let you guys know when its all done. Which should be the beggining of next week.
06-26-2003, 01:43 PM
#7
Three Wheelin'
44mag, if you have your curb weight and a dyno rw torque curve for your engine (or someone has one for a stock 86 NA, if yours is stock), I can model the acceleration numbers for you and come up with a good estimate of the changes/improvements with the gearing change.
EDIT: Didn't see your last post before I posted. Real world numbers will be better; do you have any timed runs for before/after, or will you be using the seat-of-the-pants dyno?
EDIT: Didn't see your last post before I posted. Real world numbers will be better; do you have any timed runs for before/after, or will you be using the seat-of-the-pants dyno?
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06-26-2003, 01:45 PM
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I was originally going to swap the 4.11 r&p from a 1980 924 but the porsche dealer in my city took two months to tell me that they cant find that part so I went with the aftermarket. I know its not really worth it to dissect your transaxle but I already chewed up the stock r&p (it was brutal)... so if its broken make it better. I think that powerhaus will be making a 4.30 and a 4.70 but dont quote me on that I went with the 4.11 because I want it to be relatively reasonable on the highway.
06-26-2003, 01:52 PM
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I g-teched my car last summer with the 3.89 and I ran a 15.8 @89mph and a 7.7 0-60. I think thats pretty fast for a stock 8v with nothing but fat *** tires, but thats probably why I toasted my R&P in the first place, my winter car is a 1990 3.0 Pajero and that thing takes anything I can throw at it. But anyway I'm not expecting a huge improvment over stock but I think 2-3 carlengths should be reasonable.
06-26-2003, 02:06 PM
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Here is a comparison of the gearing with the 3.89 and 4.11 R&P's. This is using the shorter 5th gear in a 924S or late 944 gearbox. Also, the tire circumference is calculated from the 215/60-15 size. These numbers are with a 6,500 rpm shift point.
If these numbers don't make sense to you, let me know.
<img src="http://stevelavigne.com/images/944gearing.jpg" alt=" - " />
If these numbers don't make sense to you, let me know.
<img src="http://stevelavigne.com/images/944gearing.jpg" alt=" - " />
06-26-2003, 04:13 PM
#12
Burning Brakes
I think it could granade much quicker with the 4:11
have a read:
<a href="http://forums.pelicanparts.com/showthread.php?s=&threadid=115828" target="_blank">http://forums.pelicanparts.com/showthread.php?s=&threadid=115828</a>
have a read:
<a href="http://forums.pelicanparts.com/showthread.php?s=&threadid=115828" target="_blank">http://forums.pelicanparts.com/showthread.php?s=&threadid=115828</a>
06-27-2003, 09:57 AM
#13
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Mmmm, Powerhaus... yummy... gears... yummy...
Just tore one of my boxes apart, stock 924 5-speed (80-82). That's where the 4.11 can come from, it's the stock ratio, and I've heard it can be swapped into the 944 box. It's the hot setup for ITS cars. I've also heard that there's an Audi that has a 4.3 you can swap in. Haven't found it yet, though. Went hunting, came up with a 4.9, but it doesn't fit. Oh well. Maybe I'd better call Powerhaus! What do they charge for their gears?
Just tore one of my boxes apart, stock 924 5-speed (80-82). That's where the 4.11 can come from, it's the stock ratio, and I've heard it can be swapped into the 944 box. It's the hot setup for ITS cars. I've also heard that there's an Audi that has a 4.3 you can swap in. Haven't found it yet, though. Went hunting, came up with a 4.9, but it doesn't fit. Oh well. Maybe I'd better call Powerhaus! What do they charge for their gears?
08-20-2020, 06:24 PM
#14
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Mmmm, Powerhaus... yummy... gears... yummy...
Just tore one of my boxes apart, stock 924 5-speed (80-82). That's where the 4.11 can come from, it's the stock ratio, and I've heard it can be swapped into the 944 box. It's the hot setup for ITS cars. I've also heard that there's an Audi that has a 4.3 you can swap in. Haven't found it yet, though. Went hunting, came up with a 4.9, but it doesn't fit. Oh well. Maybe I'd better call Powerhaus! What do they charge for their gears?
Just tore one of my boxes apart, stock 924 5-speed (80-82). That's where the 4.11 can come from, it's the stock ratio, and I've heard it can be swapped into the 944 box. It's the hot setup for ITS cars. I've also heard that there's an Audi that has a 4.3 you can swap in. Haven't found it yet, though. Went hunting, came up with a 4.9, but it doesn't fit. Oh well. Maybe I'd better call Powerhaus! What do they charge for their gears?
The ring and pinion (4.30:1) is sourced from a 1979 Audi 5000 Diesel. The transmission was rebuilt by Porsche shop in No. Va. in 2009 with a fresh LSD and short 5th gear.
The transmission has been not been in a car since 2016. Before that the transmission had 3 seasons of use.
The gearing change using the R&P will greatly enhance the speed and quickness of your otherwise stock 944. Asking price is $2200. Located in Winter Park, Fl.
Contact Rick at: 407.832.4044
