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3:70
- Thread starter lgurley
- Start date
Hi Larry,
The 3.70's are OK, but the lower the ratio, the better. The little 2.8 V6 has a short stroke, so isn't long on torque. It doesn't perform well under 3,000 rpm. The T5 you are using will let your engine cruise happily at any freeway speed you'd like, even illegal speeds, with a set of 4.22's like Jim Ellis is running. Remember, the lower the gear, the better your Alpine will perform.
Jose
The 3.70's are OK, but the lower the ratio, the better. The little 2.8 V6 has a short stroke, so isn't long on torque. It doesn't perform well under 3,000 rpm. The T5 you are using will let your engine cruise happily at any freeway speed you'd like, even illegal speeds, with a set of 4.22's like Jim Ellis is running. Remember, the lower the gear, the better your Alpine will perform.
Jose
RootesRacer
Donation Time
I'd go with the 3.70, its going to be a stronger ring and pinion since it has more teeth on the pinion (10 vs 9 on the 3.89 and 4.22).
Just my opinion though.
If you dont agree, I will happily trade a very nice 3.89 pumpkin for that 3.70 provided its a quiet gearset.
Just my opinion though.
If you dont agree, I will happily trade a very nice 3.89 pumpkin for that 3.70 provided its a quiet gearset.
Jim E
Donation Time
The 3.70 gear is all wrong for the 2.8 conversion, well it might be OK if you are using the 4 cylinder version of the T5 transmission, with that configuration it might actually be the best gear set you can get with a stock Alpine rear end. With any of the other T5 transmissions this gear is not going to be what you want. Around town the car is not going to be near as snappy as it could be. Now depending on you and how you drive this may not be much of an issue on the around town side of things. On the highway this gear is just going to be a real pain in the behind with the 5.0 or 3.8 T5 OD ratio. The engine is just not going to be in a happy RPM band. With my car and a 5.0 T5 and a 3.89 gear the car was not happy on the highway, sluggish and MPG was down with the change to the 4.22 gear the car was more in the power band and MPG went up the 4.22 gear also made the car much more snappy around town, stop light to stop light. IMO the 3.70 gear would just kill the performance of the conversion sluggish around town and on the highway the worst of both worlds. The 2.8 lives in the higher RPM range and for my money the conversion really needs a 4.10 gear or more, the 4.22 gear is the ticket!
Jim E
Donation Time
hahahhahahaha.... I started to post on this and the phone rang when I got back and finished Jose and Jarrid had posted total oposite opinions to each other though Jose and I share the same view point.
Ok here is my opinion........ there are two things you can do to spoil the 2.8 conversion.... one is not enough gear the other is not enough cam. I have all the cam you can put in the thing and a 4.22 gear. I get 25 plus MPG on the highway and the car is very snappy to say the least. as my one buddy says "That thing will eat" even with a stock cam the 2.8 is going to be much happier with the 4.22 gear. Put a rev limiter on it and let the little dog eat.
Ok here is my opinion........ there are two things you can do to spoil the 2.8 conversion.... one is not enough gear the other is not enough cam. I have all the cam you can put in the thing and a 4.22 gear. I get 25 plus MPG on the highway and the car is very snappy to say the least. as my one buddy says "That thing will eat" even with a stock cam the 2.8 is going to be much happier with the 4.22 gear. Put a rev limiter on it and let the little dog eat.
bulldurham
Platinum Level Sponsor
3.70 gear
What do you think about a 3.909 MGB/14". Will that extra inch help much?
What do you think about a 3.909 MGB/14". Will that extra inch help much?
RootesRacer
Donation Time
My opinion had to do with the stronger of the two, as to gear ratio, it depends on what the final drive ratio of the trans is. If you go with the mustang or capri 4 speed, then 3.70 would be the best you could do.
I'd still take that 3.70 for my rootes engined alpine, even with 25% OD.
Hi Jim,
The reason you and I agree, is because we have owned V6 Alpines. We know that the little 2.8 will live with almost any gear, but if you really want to let it perform, it needs a low gear. As far a strong, I don't think the 2.8 would stress the pinion gear on a 3.89/4.22 to where it would wear or break.
The 2.8 V6 not only performs better with the lower gear, but as you have experienced, it is much more economical with the lower gear. Any engine will be more economical when it is working at it's sweet spot. Some guys don't want a racer, so think they don't need a lower gear set, but even with lower gears, they will get a car that is well rounded., noit just a racer.
Jose
The reason you and I agree, is because we have owned V6 Alpines. We know that the little 2.8 will live with almost any gear, but if you really want to let it perform, it needs a low gear. As far a strong, I don't think the 2.8 would stress the pinion gear on a 3.89/4.22 to where it would wear or break.
The 2.8 V6 not only performs better with the lower gear, but as you have experienced, it is much more economical with the lower gear. Any engine will be more economical when it is working at it's sweet spot. Some guys don't want a racer, so think they don't need a lower gear set, but even with lower gears, they will get a car that is well rounded., noit just a racer.
Jose
RootesRacer
Donation Time
OK, OK, I concede!
I drove for years in a 77 merc capri with 2.8, 2bbl 4 speed and the stock 3.09 final drive ratio, and it worked pretty good in a 2700lb car, not to mention 27mpg.
Now would someone please send me that 3.70?
I drove for years in a 77 merc capri with 2.8, 2bbl 4 speed and the stock 3.09 final drive ratio, and it worked pretty good in a 2700lb car, not to mention 27mpg.
Now would someone please send me that 3.70?
Hi Doug,
The 3.9 you mention will work also, just that the lower you go, the better the 2.8 will perform. With the T5, the overdrive will let you cruise on the freeway at any speed you wish, because the 2.8 loves to rev. It will be as happy at 4,000, as the Alpine four is at 3,000.
For those who want the baddest 2.8 V6 Alpine available, you'll need to go with a set of 4.11's (the lowest ration you can get for the 8"). If you are using a stock type rear end, you should get one with a set of 4.22"s.
Jose
The 3.9 you mention will work also, just that the lower you go, the better the 2.8 will perform. With the T5, the overdrive will let you cruise on the freeway at any speed you wish, because the 2.8 loves to rev. It will be as happy at 4,000, as the Alpine four is at 3,000.
For those who want the baddest 2.8 V6 Alpine available, you'll need to go with a set of 4.11's (the lowest ration you can get for the 8"). If you are using a stock type rear end, you should get one with a set of 4.22"s.
Jose
lgurley
Donation Time
3.89/4.11
Ok. I will want to use either the 3.89, 4.11 or the 4.22. I bought my 3.70 to go behind a non syncro Alpine overdrive. It works nicely there. I will be moving this setup to one of my other projects.
My question now is where do I get one of these ratios for my V6. I have the chunk from the one I removed plus one in another SV plus two in SIVs. Will one of these fit and how can I tell?
Ok. I will want to use either the 3.89, 4.11 or the 4.22. I bought my 3.70 to go behind a non syncro Alpine overdrive. It works nicely there. I will be moving this setup to one of my other projects.
My question now is where do I get one of these ratios for my V6. I have the chunk from the one I removed plus one in another SV plus two in SIVs. Will one of these fit and how can I tell?
4.11 Gearing
I agree (now) with the 4.10/11 alxe ratio, as mine has a 3.32 and everything you have said is correct. If I'm not seriously "motivatin'" when I go into 5th the rpm drops and I go back into 4th. I'm considering regearing my current car which has the Dana 44. Question: If I do that, I know I'll need the larger carrier but can I still use the same locker?
OK. Let's look at the other end. My math tells me that with the 4.10/11, first gear becomes nearly worthless. Jim and Jose-do you do second gear starts normally or can you still use first for something besides pulling stumps?
I agree (now) with the 4.10/11 alxe ratio, as mine has a 3.32 and everything you have said is correct. If I'm not seriously "motivatin'" when I go into 5th the rpm drops and I go back into 4th. I'm considering regearing my current car which has the Dana 44. Question: If I do that, I know I'll need the larger carrier but can I still use the same locker?
OK. Let's look at the other end. My math tells me that with the 4.10/11, first gear becomes nearly worthless. Jim and Jose-do you do second gear starts normally or can you still use first for something besides pulling stumps?
Hi Larry,
I don't know about interchangeability of your different parts, but I highly recommend going with the Ford 8" anyway, rather than keeping the stock Alpine unit. Some think the Alpine rear is good enough, but my experience hasn't been too good with them. Of course, I am really hard on my cars, because I drag raced them every chance I got. If you are going with the big power engine, go with the Ford. It isn't cheap to modify to fit the Alpine, plus installing a set of 4.11's, but you will be very happy you did.
Jose
I don't know about interchangeability of your different parts, but I highly recommend going with the Ford 8" anyway, rather than keeping the stock Alpine unit. Some think the Alpine rear is good enough, but my experience hasn't been too good with them. Of course, I am really hard on my cars, because I drag raced them every chance I got. If you are going with the big power engine, go with the Ford. It isn't cheap to modify to fit the Alpine, plus installing a set of 4.11's, but you will be very happy you did.
Jose
Hi Nick,
I can't tell you about your Dana or if specific parts will fit, but I can tell you about the effect of the gear ratio. The only five speed transmission that isn't good to use on this conversion, is the T54 from behind the four cylinder engine. That first gear is way too low, so is best to not use it. All the other transmissions will work fine. First gear will be quick, but not to where you can't use it. Your Alpine will be real peppy in first gear, and all the other gears as well. Which transmission do you have? If it is from a four cylinder, I would suggest getting rid of it and getting one from a 1996 or later Mustang 3.8 V6.
Jose
I can't tell you about your Dana or if specific parts will fit, but I can tell you about the effect of the gear ratio. The only five speed transmission that isn't good to use on this conversion, is the T54 from behind the four cylinder engine. That first gear is way too low, so is best to not use it. All the other transmissions will work fine. First gear will be quick, but not to where you can't use it. Your Alpine will be real peppy in first gear, and all the other gears as well. Which transmission do you have? If it is from a four cylinder, I would suggest getting rid of it and getting one from a 1996 or later Mustang 3.8 V6.
Jose
RootesRacer
Donation Time
On the dana 44, the high ratio powr-loc is different than the low ratio powr-loc, basically the thickness of the ring gear is different so the cases are different due to the different ring gear offset. 19 spline 44 powr-locs in the high and low gear configuration are usually not hard to find and shouldnt cost too much either.
Thanks guys!
Well that answers that. Cool.
Jose, my trans is from a Mustang 5.0 GT which was what I was advised to locate. I didn't have to machine the input shaft.
Here in Phoenix, the gearing and locker swap shouldn't be an issue as a bunch of Jeep guys dump their 4.10's and go numbericaly higher and there are good companies to do the swap. Also I have an associate at Dana that migh help me out.
RootesRacer-When you say the cases are different, do you mean the pumpkin itself?
Again, thanks for the help.
Well that answers that. Cool.
Jose, my trans is from a Mustang 5.0 GT which was what I was advised to locate. I didn't have to machine the input shaft.
Here in Phoenix, the gearing and locker swap shouldn't be an issue as a bunch of Jeep guys dump their 4.10's and go numbericaly higher and there are good companies to do the swap. Also I have an associate at Dana that migh help me out.
RootesRacer-When you say the cases are different, do you mean the pumpkin itself?
Again, thanks for the help.
RootesRacer
Donation Time
Dana 44 doesnt use a pumpkin, its a salisbury or back loading axle.
A pumpkin (hotchkiss type) is like whats on the stock alpine or ford 8/9 inch, where the gears and pinion came out of the front as a unit (pumpkin).
What I mean by case is the "carrier" for the ring gear, where the spiders and clutch plates are located.
Dana/spicer made 2 distinct units for each axle spline type, one for high and one for low numerical ratios, the specific ratios of each type I do not recall.
For an unmodified tiger dana 44, the case/carrier type is the 19 spline with the internal semi-floating button which allows the axles to put force on one another so you can shim the tapered bearings for proper preload.
Not all powr-loc cases/carriers will have the button inside but you MUST get one that does.
Hi Nick,
The T5 you have is perfect for the lowest set of gears you can get into your Dana. It has the highest percentage overdrive of all of the T5's. First gear will be tall enough to not be too low for the V6. I think you will have a great combination when you get it done.
Jose
PS. Do you have the pilot bearing adapter needed for that transmission?
The T5 you have is perfect for the lowest set of gears you can get into your Dana. It has the highest percentage overdrive of all of the T5's. First gear will be tall enough to not be too low for the V6. I think you will have a great combination when you get it done.
Jose
PS. Do you have the pilot bearing adapter needed for that transmission?
Hi Jarrid,
The Capri you drove years ago, had only a four speed. The new five speeds have an overdrive, which allows a low rear gear, yet still have reasonable cruising speed on the freeway. The five speed really makes the little 2.8 V6 come into it's own.
Jose
The Capri you drove years ago, had only a four speed. The new five speeds have an overdrive, which allows a low rear gear, yet still have reasonable cruising speed on the freeway. The five speed really makes the little 2.8 V6 come into it's own.
Jose
OK, OK, I concede!
I drove for years in a 77 merc capri with 2.8, 2bbl 4 speed and the stock 3.09 final drive ratio, and it worked pretty good in a 2700lb car, not to mention 27mpg.
Now would someone please send me that 3.70?
RootesRacer
Donation Time
But I already conceded...