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Differential for Sprite/Elva
- Thread starter Michael Oritt
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Hap Waldrop
Yoda
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I would imagine a a Elva with B-series running gear might take a little different gearing than a Spridget because of more torque, but not much, I would think even in a Elva 3.55 would take way too long to wind up. I would think a 3.90 would be the best overall choice for a Elva on the race track, maybe a 4.22 for the tighter/slower tracks.
Jeff at VIR, in a 948 a 4.22 would work fine, with a LP or FP 1275 a 3.90 is the way to go. Daytona is the ony place I can think that I have raced that a 3.7 might be a good choice for a 1275, and the 3.9 for the 948.
Oh and just for grins, I have a 1.65 first gear /ubbthreads/images/graemlins/smile.gif
Jeff at VIR, in a 948 a 4.22 would work fine, with a LP or FP 1275 a 3.90 is the way to go. Daytona is the ony place I can think that I have raced that a 3.7 might be a good choice for a 1275, and the 3.9 for the 948.
Oh and just for grins, I have a 1.65 first gear /ubbthreads/images/graemlins/smile.gif
Hap Waldrop
Yoda
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Jack, you don't want a 5.38 in your BE, as Jeff stated this gearing came in Morris Minor vans that made city deliveries in the UK, most of them never even saw 50 mph. You put a 5.38 in your BE and hit a backroad and want to run 60mph, it will sound like that litte motor is going to come out of the hood. I would think a perfect street gear for the 948 would be a 4.22.
D
Deleted member 3577
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If Michael has the standard MGA box...
3.64-----2.21-----1.37-----1.0
If he has the C/R
2.45-----1.62-----1.27-----1.0
Hap, 1.65??? what are the other gears?
3.64-----2.21-----1.37-----1.0
If he has the C/R
2.45-----1.62-----1.27-----1.0
Hap, 1.65??? what are the other gears?
Hap Waldrop
Yoda
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1.65, 1.36, 1.115, 1.1 Taylor Race Engineering gearbox, Webster/Hewland gears made to fit the stock Midget gearbox, Hydraulic throw out bearing, dog mesh straight cut gears, no need for the clutch after you get going, pretty slick piece, but it had a pretty slick price as well, I just tore it down for the first time and we REMed the internals.
I got a second gearbox to build for myself, It's a Leason which is similar to the Jack Knight dog mesh Midget box, except 1st gear is still a non sycromesch gear, they are referred to as crash boxes, I bought the gear set new for a song. This gear set is made to fit in as the original, you can't change the gear ratios like the Taylor box but the stack will do fine and for the price, I could not go wrong.
I got a second gearbox to build for myself, It's a Leason which is similar to the Jack Knight dog mesh Midget box, except 1st gear is still a non sycromesch gear, they are referred to as crash boxes, I bought the gear set new for a song. This gear set is made to fit in as the original, you can't change the gear ratios like the Taylor box but the stack will do fine and for the price, I could not go wrong.
D
Deleted member 3577
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Holy torque-band Batman.......That's a close ratio box!!
Never driven anything like that before.
I do like the REM idea......Even if it just looks cool.
Never driven anything like that before.
I do like the REM idea......Even if it just looks cool.
Hap Waldrop
Yoda
Offline
[ QUOTE ]
Holy torque-band Batman.......That's a close ratio box!!
Never driven anything like that before.
I do like the REM idea......Even if it just looks cool.
[/ QUOTE ]
It's great on the race track, the useable first gear really comes into play in the slower corners and lets you keep the rpms up in the slow stuff. I won a race at VIR a few years ago by having it, the guy I was racing with had a sc/cr spridget box, which won't allow him to go down to first in the slow corners. We were pretty even in top speed and in driving talent, the difference was I could get him 2 car lengths in three of the slower corners every lap, when the race was done, it made for a nice cushion, I'm 100% convinced the gearbox was the difference between our two cars. Talking about the closeness of the gears, it drops about 300 rpms only between gear shifts, so you're grabbing them pretty quick till you get to fourth. I'm pretty budget minded on my own stuff, so REming the gears was not something I had really thought was within my budget, but a local guy is doing alot of this for Nascar and knew we build a few gearboxes and offered me a buddy deal I couldn't refuse. He does all the gears for many top Nascar teams and does all their wheel bearings as well, I think next I'm going to give him a new set of wheel bearings to do for me, he showed the before and after on the wheel bearings and no doubt they turn easier. The REMed gears look almost too good to put in the box.
Holy torque-band Batman.......That's a close ratio box!!
Never driven anything like that before.
I do like the REM idea......Even if it just looks cool.
[/ QUOTE ]
It's great on the race track, the useable first gear really comes into play in the slower corners and lets you keep the rpms up in the slow stuff. I won a race at VIR a few years ago by having it, the guy I was racing with had a sc/cr spridget box, which won't allow him to go down to first in the slow corners. We were pretty even in top speed and in driving talent, the difference was I could get him 2 car lengths in three of the slower corners every lap, when the race was done, it made for a nice cushion, I'm 100% convinced the gearbox was the difference between our two cars. Talking about the closeness of the gears, it drops about 300 rpms only between gear shifts, so you're grabbing them pretty quick till you get to fourth. I'm pretty budget minded on my own stuff, so REming the gears was not something I had really thought was within my budget, but a local guy is doing alot of this for Nascar and knew we build a few gearboxes and offered me a buddy deal I couldn't refuse. He does all the gears for many top Nascar teams and does all their wheel bearings as well, I think next I'm going to give him a new set of wheel bearings to do for me, he showed the before and after on the wheel bearings and no doubt they turn easier. The REMed gears look almost too good to put in the box.
D
Deleted member 3577
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I think Michael told me he has a stock cam in the Elva.
(required for his vintage racing group?)
What is a 3.9 at 6800 rpms?
About 95 mph?
(required for his vintage racing group?)
What is a 3.9 at 6800 rpms?
About 95 mph?
Tim Hollister
Jedi Trainee
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WhatsThatNoise said:
Just jumped one of those online mph calculators (love Google!) and it came up with 103.7 mph using a tire diameter of 20" (as in 8" by 20" by 13" Hoosiers I run on the race cars). Of course with a larger diameter tire, the speed will be somwhat higher.
Tim