Jump to content

Recommended Posts

Posted

hi i have broken my diff three days back with pushing the a little hard .. when i opened the diff it showed 3.8 ratio 35/9 i dunno what diff it is but it is from toyota..

my car is daily driven should i stick to 3.8 or try different because i want to be quick in drag race .... the engine is sr20 redtop totally stock with s15 turbo and bpu mods like fmic,ic pipings,3 inch down pip to cat back and avcr boosting 12 psi

 

 

just have a vid for now

 

http://www.youtube.com/watch?v=LdWn3lt33vY

 

 

feedback is appreciated

Members dont see this ad
Posted

if ya handy with a welder, tarago diff suited me, lighter then hilux and a ton cheaper, still uses same 4x114.3 jus tracks 40mm wider from memory

but if ya don't want it to ever break go a hilux for drag i guess

Posted
go for 3.8 or should i try 4.1 or 4.3 for drag

 

Depends on how far/fast you drag to. You can lower all the gears by going to 4.3, but you will have to change into 3rd at a lower speed and may have to change into 4th where in the old days you were still in third.

 

So its important to cross the finish line with the minimum number of geachanges, as well as having a low enough diff to get off the line well. If you lower the diff to 5.1 you wll be making a lot of gearchanges.

 

Investigate what the vans run, see if you can get a 4.6.

Posted

i run 3:7 hilux, which is perfect for the power range i run

 

 

you are going to struggle to find a tarago diff ( i only found 1 in brisbane at the wreckers), and they will expensive.

i think you should go for a r31 diff because they are cheap, strong, have factory lsd and aftermarket options, disc brakes, and 4x114.3 stud pattern.

ratios are 3.89, and you can also get 4.11

Posted

The 4.3 is the common ratio that i have seen around the traps,

 

over 400m given your setup, would be ideal, you can get off the line rather snappy and with MT's on board,

 

You should be able to squeeze some more boost out of the turbo safely also

 

You are going to have to get out to some test and tunes

Posted

yea 16 to 17 psi is achievable out of turbo with some nitrous ..as for 3.7 car will become a little lazy and good for topend but mine is sr20 not 1jz so my power will break soon 4.1 or 4.3 is ideal

Posted

thats some pretty serious speed you have there for 11.8!

 

you have alot of power, so i would think that perhaps 4.3 might be a bit short.

 

i would be inclined to go with 4.1 or even the 3.7. but hey just a feeling here...

 

if you are dead set on drag racing being the goal, get yourself a gear ratio calculation spreadsheet, and you can work out how to get hte maximum power to the ground over 400m.

 

i don't know much about drag racing, but i suspect you want to be mid 4th gear by the finish line?

 

either way pick what you want, then caluclate it out.

 

i think i have a spreadsheet at home if you want a copy send me a pm with an email address.

Posted

dave you have been in my car and is rather punchy with the 3.7 ratio, oh i was in third gear when i jumped past you and reed haha

 

i run up to 20ps in winteri, i have not put mine down the track but if i was lookin for numbers i would look at 4.11

 

so either which way you are going to suffer bottom or top, unless you forge the engine IMO

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...