Diff question..
Hi guys,
Hoping to get a new diff into the car soon after the new year.
Unsure if I'll go 3.7's or 3.9's, Kinda thinking 3.9's at the moment (if anyone has any info or valid points why I should go for one over the other that'd be great).
Anyway, I've been quoted about $1500 to get the new gearing etc all fitted ( or maybe a new diff, I dunno how they do it). But then it'll cost me whatever to get the speedo calibrated.
Now I've seen diffs for sale on Ebay for 800-1000 that are apparently completely reconditioned/new with whatever gearing u want etc.
I'm just wondering if this is worth buying and fitting to the car myself (how hard is it?), or if I should just pay someone else to do it and do it properly ?
Just thinking I MAY be about to save myself some money that's all...
Diff is for my VT SS S1, with IRS.
( .Y. )
Its easy enough to fit an IRS diff yourself mate.
Its just a bit heavy so a trolley jack is a good idea.
Id say you would have the old one out and the new one in within 3 hours if it was your first time and wanted to take your time.
Nice!
That'd be alright, cause then I can just take it straight to getting the speedo recalibrated to suit the diff. (Anyone know how hard/expensive this is).
Apparently LS1's are just a matter of plug and play into a PC and they calibrate it easily from there within minutes, haven't heard how the 304's are done though.
Are those ebay diffs worth looking at? Anyone used them?
I think I heard that fitting a diff was quite technical and took a lot of time and if you don't know what you were doing you could fk it all up.
white trash hillbillie
i've heard the 5L delco computer can be tuned to fix the speedo, dunno about cost or what tuning program they use.
i got one of those ebay diffs in 3.9 lsd behind a 420rwhp 6L in a vs ss irs, i dont give it that much of a hard time but i cant complain about it so far
Originally Posted by UFO
How do you find the 3.9?
I've not been in a car with either of the ratio's I'm looking at so I don't know how they perform.
Is it revving high at 100kmph ?
Anyone else got any feedback regarding 3.9's or 3.7 diff gears?
Your car manual or auto? Much highway driving? All i can say is i put 3.46's in my SV6 and it the best mod ive done by far.
Auto.
Don't currently do too much highway driving, only every now and then
3.7's would be a good way to go imo. Unless you are after max acceleration at all costs then go the 3.9's.
That's what a friend told me.
He thinks I'd be crazy to go 3.9s in it when it's my daily and only car.
Everyone comments on how much of an improvement was made by the change, I'm really excited to find this out for myself (well... fingers crossed it all goes well...)
I do want to build a very quick car, but I don't want to make it a nuisance to drive at 100kmh for extended periods of time (my folks live at the end of a very boring and long freeway).
What ratio is in your car as standard?
I'm not sure I think it's 3.07 or 3.08 from factory?
Well I've been quoted about $930 for the 3.9's.
I think the 3.7's came out more at about $980
Really want to get this done, damn Christmas though... I swear it's gonna drain me of a lot of money.
What rpm would you be on, at 100km on a 3.9 diff.
Cheers Brenton
ɹoʇɐɹǝpoɯ ǝsınɹɔ ɐʍ
^About 2600 in my vz. I'd 100% go 3.9s, the difference over 3.7s is basically nothing and you'd end up kicking yourself for not doing it. 3.9's were the best mod i've done so far, i got "motive" brand diff gears for arounf $500 delivered, and they have held up good so far and don't whine etc.
Black, Red leather, 20" Pentagons, Red walls, Lowered, OTR, Mafless, 3.9s, Diff dumpers, 341rwhp...
185i, Chasers, Flappers, Venetians, Sunvisor, Twin diff dumpers, 194rwhp...
▲
▲ ▲
parkway, did u do the work yourself?
How far out would the 3.9's make my speedo ?
would it be out by a particular percentage or ?
Obviously I'd aim to get the speedo recalibrated, but in the meantime I wouldn't want to get slapped with a fine for nothing.
Easy way is to get someone with a stock car in front of you doing 100KMH and see what your doing. There is no way I would go 3.9's or 7's, 3.45 or around about is what I want for the street. You would be suprised how much extra punch you get over the stock diff while maintaining decent highway economy.
50LTRv8
Posting Permissions
LinkBack URL
About LinkBacks
Reply With Quote