We have a book chassis 2 litre pinto on 5 speed type 9 box, with 15 inch wheels, 185 x 60s and found that when we are on motorway at 70mph we are doing 3200 rpm which seems a bit high and the 1.3cc diff has a bit of a whine above 30mph as well. Tried seraching but unable to find any post that recommend the best ratio for us to change to for normal town driving, a bit of track action hopefully one day, but still give us a goor pull away and acceleration. Thinking of a RS2000 one ( 3.54 I think ) Your suggestions please.

For more relaxed cruising you want a lower diff number eg 3.5:1

For better acceleration you would want a higher number - eg 4.4:1

If it was me I would have a 5.1:1 with a pinto in order to scare bike engined cars up to about 50 mph

Can i have a glass of what you are on please?????


I know this is of limited use, on my sierra diffed car im using 3.92:1 with pinto and it seems fine. Probs can be improved with slightly better ratio's on gearbox.

This one of my pet projects and i have researched it to death.
The big problem is the gearbox ratios in the Type 9 (worse in the MT75) Ist is to low and only the Cosworth T5 has a usable 1st thats why the racers use a Quaffe or BGH gearset with a 1st from 2.8 and a .93 5th.

I have modified and fitted a V6 Type 9 with the 3.36 1st as opposed to the 3.6 of the standard box still only gets me to 30 ish in first but 60 in second with the 3.9 diff.

Now comes your choice if you want best performance 2nd to 4th then the 3.9 is the diff for you also helps with the standard power Pinto, if you want a more usable 1st and better crusing then the 3.6 is the one and this works well with the higher output engines, i would suggest that BHP around 130 or more, is about the change over point. But then it comes down to personal choice, as changing the diff is not much of a job and a standard non LSD 3.6 is cheap, give it a try.

cheers gents, it's back to ebay for me then.