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  #1  
Old 22nd October 2011, 10:48 AM
DaveyB DaveyB is offline
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Default 3.38 ratio diff

Hi it's me again going on about diffs could someone tell me if a 7 inch 3.38 ratio diff would be all right for a Haynes roadster. That's if there is someone around who is not at Exeter. I will probally use a 1.6 pinto to a type 9 box
Thanks again
Daveyb

Last edited by DaveyB : 22nd October 2011 at 10:50 AM.
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Old 22nd October 2011, 11:03 AM
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ozzy1 ozzy1 is offline
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3.38 would give you slow acceleration.
3.62 or 3.92 would be better.
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Old 22nd October 2011, 10:23 PM
DaveyB DaveyB is offline
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Thanks ozzy 1 just the reply I was hoping for.
DaveyB
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Old 23rd October 2011, 10:18 AM
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twinturbo twinturbo is offline
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Normaly that ratio would be paired with an engine with much more torque than a 1.6 Pinto. You would not "sensibly" put the combination in a sierra as the engine would struggle. It may fell ok in the roadster.

However, you not going to have the power/torque combination to get the value out of that diff which is higher top speeds. And, realy, the roadster is not cut out for HIGH speeds and is more of a point to point acceleration and braking car.

TT
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Old 23rd October 2011, 11:46 AM
robo robo is offline
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Have a play with this.
http://www.boosttown.com/gearbox_dif...calculator.php

TT`s right but dont go to far that way or it will drive you bonkers on a run.

Bob
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Last edited by robo : 23rd October 2011 at 11:56 AM.
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Old 23rd October 2011, 01:06 PM
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I once swapped a DOHC for a 2.9 in a sierra 4x4, keeping the DOHC 3.92 diffs. It was much more sprightly than with the 3.62's but 1st was kind of superfluous.

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Old 23rd October 2011, 08:40 PM
DaveyB DaveyB is offline
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Thanks again for the info, someone has offered me a 1.6 pinto and so thought I would be going down this route using that engine, I have some drive shafts and no diff, have just been looking at diffs for push in shafts and been concerned that they may not fit I know of a 3.62 diff that will fit and I have seen a 3.92 but I,m not sure if that will fit, and not sure of which one to go for any suggestions. Hope I making some sense!
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Old 23rd October 2011, 09:05 PM
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3.92, to give the pinto a chance..

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