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Axle Diff Ratio


farmerjack
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Can someone confirm that my Manta B Coupe 2.0 GTE 1987 has a 3.44:1 diff? ( assuming it is standard)

Secondly, wishing to lower the ratio somewhat, can I fit a 3.67 diff from a 1.8?

If so what is involved? I see someone is advertising a 4.7 and 5.2 on ebay but looking for serious money.

best wishes

FJ

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Can someone confirm that my Manta B Coupe 2.0 GTE 1987 has a 3.44:1 diff? ( assuming it is standard)

Secondly, wishing to lower the ratio somewhat, can I fit a 3.67 diff from a 1.8?

If so what is involved? I see someone is advertising a 4.7 and 5.2 on ebay but looking for serious money.

best wishes

FJ

You are correct about the GTE having a 3:44.

You can do a stright swap with the lower ratio 3:67 axle from the 1.8.

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  • 1 year later...

You are correct about the GTE having a 3:44.

You can do a stright swap with the lower ratio 3:67 axle from the 1.8.

i have a 2.0 gt/e hatch and a 1.8 axel. i was planning on fitting the lower ratio diff from the 1.8 to my 2.0 axel to gain better acceleration.

has anyone done this already? ( i'm sure that they have)

is it as strong?

and does it make a big difference?

i'm not bothered about going over a hundred but i want to get there bloody quick!!

thanks

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Monkeynuts, the axles are the same so you might as well put the whole 1800 axle into your car, changing the diff into the existing axle is a lot more work.

Vealmonkey, the 1.9 B series had the 3.67 diff so I assume A series would be the same, it was only the 2.0 cars that had the 3.44 diff.

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Monkeynuts, the axles are the same so you might as well put the whole 1800 axle into your car, changing the diff into the existing axle is a lot more work.

Vealmonkey, the 1.9 B series had the 3.67 diff so I assume A series would be the same, it was only the 2.0 cars that had the 3.44 diff.

This is not correct. The A series came with a wide variaty of diff´s . The 1,2 came with a 4,22, the 1,6 and some 1,9 came with 3,67 and some 1,9 GT/E came with 3,67 and 3,44 and some even came with a 3,11 which gave them a top speed around 200km/h still with only a 4 speed box.

The 1,6 1,8 1,9 and 2,0 diffs is identical and can be swapped with no problems at all.. The 1,2 / 1,3 are different.

A 3,67 will give you better acceleration, but you will also get shorter gears. So i would recommend it for anyone with a original 2,0E 110hp engine, it will acutally be give you a bit of an advantage (i have played around with diffs alot). For engines with more than 125hp and especially good torque engines like the 2,2 and 2,4 i do not recommend it. You dont get the benefit of the torque. We did it on a Manta A series with a mildly tuned 155hp 2,2 and it was shite.. So we changed back to the 3,44 which was better. I actually believe this car would have been best of with a 3,11 but those are hard to come by.

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This is not correct. The A series came with a wide variaty of diff´s . The 1,2 came with a 4,22, the 1,6 and some 1,9 came with 3,67 and some 1,9 GT/E came with 3,67 and 3,44 and some even came with a 3,11 which gave them a top speed around 200km/h still with only a 4 speed box.

The 1,6 1,8 1,9 and 2,0 diffs is identical and can be swapped with no problems at all.. The 1,2 / 1,3 are different.

A 3,67 will give you better acceleration, but you will also get shorter gears. So i would recommend it for anyone with a original 2,0E 110hp engine, it will acutally be give you a bit of an advantage (i have played around with diffs alot). For engines with more than 125hp and especially good torque engines like the 2,2 and 2,4 i do not recommend it. You dont get the benefit of the torque. We did it on a Manta A series with a mildly tuned 155hp 2,2 and it was shite.. So we changed back to the 3,44 which was better. I actually believe this car would have been best of with a 3,11 but those are hard to come by.

Agree with Montza on this one. The 2.2 180bhp motor i had in the grasser ran with a 3.11 diff (grasser is fitted with a sierra rear end) mainly because i run 2nd gear all the time. This gave me a top speed of about 80 in 2nd, and had a big top end, think it was registering 150 on rolling the rolling road. But the car would out drag a 16v witha lower diff ratio and quaife hot rod box out of the corner to mid straight, so the torque of the CIH will let you run higher ratio's.

You can play around with tyre sizes to change the gearing, i did this quite a lot with the racer as it saves changing the diff. Pretty sure there was a 12 mph difference from the smallest tyre size to the largest one. We're talking rolling radius here by the way, if i'm not making myself clear. So if your running 14's a switch to 13's with a low profile will drop it considerably.

An example, the moggy minor i'm building runs a 3.9 diff with 175/70 13 tyres but i want it on 175/50 13, but the gearing is good the way it is. The 175/70 13 tyre is 69.32 rolling, the 175/50 13 is 60.89 so the gearing would reduce too much. Fitting a 3.62 diff brings it back to where it is within 1mph. A simple tyre change could make the difference you want.

I'm pretty sure that this was the way that the GM rally team geared the 400's up and down.

HTH

Chris

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manta 400 rally car used a 5.7 diff ratio and pulled to 8500 rpm with 300 ftlb of torque.

i agree with above on tyre changes ihave a 16v redtop running 14 inch wheels with a 3.67 ratio i used toyo proxies 225/40/14 it reved like hell wheel spinning at every chance even with a ZF diff just went sideways. i now have 225/50/14 proxy r888 much better :D

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manta 400 rally car used a 5.7 diff ratio and pulled to 8500 rpm with 300 ftlb of torque.

i agree with above on tyre changes ihave a 16v redtop running 14 inch wheels with a 3.67 ratio i used toyo proxies 225/40/14 it reved like hell wheel spinning at every chance even with a ZF diff just went sideways. i now have 225/50/14 proxy r888 much better :D

were you using the standard gt/e ronal 14's ? as i was wondering how fat a tyre i could fit on the 5.5J (?) wheel rims?

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