After almost 20 years of driving ( including burn-outs, etc. ), my 914-V8 ( 327 ) with a bone stock 901, finally gave out.
Have a 77 ( short ) 930 with LSD that had been set aside as a replacement but, after careful consideration, I decided to try a ‘tall’ 901 … flipped ‘H’ into 5th, old 5th into 4th and old 4th into 3rd.
WOW … I am SO impressed, I had to share ...
Still have the off-the-line pump using the same old 2nd ( since it's fixed on the shaft ) and the ratios going up are very smooth and then I get into 5th where the tach runs around 2600 - 2800 on the highway. Makes highway driving a pleasure again !
If you have a conversion, the next time you have to go into the box, try this ‘tall’ conversion – you will NOT regret it.
BTW … the old box, it turns out, didn’t really fail … I use a 911 pull type 225mm clutch and the bolt holding the clutch fork backed out. Bottom line is I’m still very, very strong on the trusty old 901 and will state that even more strongly in my book, the 914-V8 Conversion Reference Manual.
Full Version: 'Tall' 901 ... WOW !
I just posted a topic on this. I'm looking to do the same thing. When you say you flipped H into 5th, what do you mean by this? What is H? Also, is the jump between your second gear and the new third gear (old fourth gear) too much of a reduction in rpm? Normally it's a 1,000 rpm drop in the engine speed, it should end up being a 2,000 rpm drop. Is that what happened?
Dino
After almost 20 years of driving ( including burn-outs, etc. ), my 914-V8 ( 327 ) with a bone stock 901, finally gave out.
Have a 77 ( short ) 930 with LSD that had been set aside as a replacement but, after careful consideration, I decided to try a ‘tall’ 901 … flipped ‘H’ into 5th, old 5th into 4th and old 4th into 3rd.
WOW … I am SO impressed, I had to share ...
Still have the off-the-line pump using the same old 2nd ( since it's fixed on the shaft ) and the ratios going up are very smooth and then I get into 5th where the tach runs around 2600 - 2800 on the highway. Makes highway driving a pleasure again !
If you have a conversion, the next time you have to go into the box, try this ‘tall’ conversion – you will NOT regret it.
BTW … the old box, it turns out, didn’t really fail … I use a 911 pull type 225mm clutch and the bolt holding the clutch fork backed out. Bottom line is I’m still very, very strong on the trusty old 901 and will state that even more strongly in my book, the 914-V8 Conversion Reference Manual.
Dino
QUOTE(propricer @ Apr 23 2006, 02:57 PM) 
After almost 20 years of driving ( including burn-outs, etc. ), my 914-V8 ( 327 ) with a bone stock 901, finally gave out.
Have a 77 ( short ) 930 with LSD that had been set aside as a replacement but, after careful consideration, I decided to try a ‘tall’ 901 … flipped ‘H’ into 5th, old 5th into 4th and old 4th into 3rd.
WOW … I am SO impressed, I had to share ...
Still have the off-the-line pump using the same old 2nd ( since it's fixed on the shaft ) and the ratios going up are very smooth and then I get into 5th where the tach runs around 2600 - 2800 on the highway. Makes highway driving a pleasure again !
If you have a conversion, the next time you have to go into the box, try this ‘tall’ conversion – you will NOT regret it.
BTW … the old box, it turns out, didn’t really fail … I use a 911 pull type 225mm clutch and the bolt holding the clutch fork backed out. Bottom line is I’m still very, very strong on the trusty old 901 and will state that even more strongly in my book, the 914-V8 Conversion Reference Manual.
I'm assuming your application is a V8 ...
Since the ring & pinion in a G50 can NOT be flipped, the box must run inverted in a 914-8 which usually means that most of the floor in the rear trunk must be removed ... are you quite sure you want to do this ???
Further, the gearing of a G50 is not very well suited to V8 applications so you will have to regear the box which can be expensive.
If you're determined to move away from the 901, you might consider the 930 as a better comprimise - 4 speed vs 6 speed, however ( G50/50 only ! ).
H gear is 2nd gear out of a 902 ... has a 19:32. Flipping it means to reverse the gears on the shafts so you end up with a 32:19.
In terms of speeds in gears, etc. it depends on your redline, etc. so you should contact CarQuip and get their gear selector excel spreadsheet so you can see it for yourself.
Good luck ...
Since the ring & pinion in a G50 can NOT be flipped, the box must run inverted in a 914-8 which usually means that most of the floor in the rear trunk must be removed ... are you quite sure you want to do this ???
Further, the gearing of a G50 is not very well suited to V8 applications so you will have to regear the box which can be expensive.
If you're determined to move away from the 901, you might consider the 930 as a better comprimise - 4 speed vs 6 speed, however ( G50/50 only ! ).
H gear is 2nd gear out of a 902 ... has a 19:32. Flipping it means to reverse the gears on the shafts so you end up with a 32:19.
In terms of speeds in gears, etc. it depends on your redline, etc. so you should contact CarQuip and get their gear selector excel spreadsheet so you can see it for yourself.
Good luck ...
Hey Ed,
Actually. it's for a 3.6 porsche engine. Yeah, I thought that it might require some trunk modification.
Ah, that's what am H gear is. Thanks for the clarification.
I'm not totally against the 901, it's a nice shifting transmission, it's just that I'd like to change the gearing and eliminate that fragile first gear, yet retain the five gears. Four gears in the 901 might be a bit too spread out, causing big drops in rpm when shifting.
Dino
I'm assuming your application is a V8 ...
Since the ring & pinion in a G50 can NOT be flipped, the box must run inverted in a 914-8 which usually means that most of the floor in the rear trunk must be removed ... are you quite sure you want to do this ???
Further, the gearing of a G50 is not very well suited to V8 applications so you will have to regear the box which can be expensive.
If you're determined to move away from the 901, you might consider the 930 as a better comprimise - 4 speed vs 6 speed, however ( G50/50 only ! ).
H gear is 2nd gear out of a 902 ... has a 19:32. Flipping it means to reverse the gears on the shafts so you end up with a 32:19.
In terms of speeds in gears, etc. it depends on your redline, etc. so you should contact CarQuip and get their gear selector excel spreadsheet so you can see it for yourself.
Good luck ...
Actually. it's for a 3.6 porsche engine. Yeah, I thought that it might require some trunk modification.
Ah, that's what am H gear is. Thanks for the clarification.
I'm not totally against the 901, it's a nice shifting transmission, it's just that I'd like to change the gearing and eliminate that fragile first gear, yet retain the five gears. Four gears in the 901 might be a bit too spread out, causing big drops in rpm when shifting.
Dino
QUOTE(propricer @ Apr 23 2006, 05:49 PM)
I'm assuming your application is a V8 ...
Since the ring & pinion in a G50 can NOT be flipped, the box must run inverted in a 914-8 which usually means that most of the floor in the rear trunk must be removed ... are you quite sure you want to do this ???
Further, the gearing of a G50 is not very well suited to V8 applications so you will have to regear the box which can be expensive.
If you're determined to move away from the 901, you might consider the 930 as a better comprimise - 4 speed vs 6 speed, however ( G50/50 only ! ).
H gear is 2nd gear out of a 902 ... has a 19:32. Flipping it means to reverse the gears on the shafts so you end up with a 32:19.
In terms of speeds in gears, etc. it depends on your redline, etc. so you should contact CarQuip and get their gear selector excel spreadsheet so you can see it for yourself.
Good luck ...
Ahhhh - 3.6 vs V8 ... now it makes ( more ) sense.
A 901, even strengthened, would have trouble behind a 3.6 ... look at all your options including the 915 and the G50. They are problematic from a fitment persepective but they will stand up to the power - and, as I'm sure you are aware, very expensive to implement - probably run you up to $10K, including the box.
Check with CarQuip to get the excel gear selector so you can figure out which box will work best, etc.
Good luck ... Ed
A 901, even strengthened, would have trouble behind a 3.6 ... look at all your options including the 915 and the G50. They are problematic from a fitment persepective but they will stand up to the power - and, as I'm sure you are aware, very expensive to implement - probably run you up to $10K, including the box.
Check with CarQuip to get the excel gear selector so you can figure out which box will work best, etc.
Good luck ... Ed
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