First off, i have searched and read. Im looking and ready to get my 3.9 350evo gear set. But i wanted to know before i order them, Has anyone here installed them on a 5AT? all i read is those with 6MT. If you have, what is your impression of them on a 5AT?

Second, With having a 5AT with 3.9 gears, is there anything else i need?
Im looking at ordering this coming week, so need some info asap.

Thanks in advance,
James

P.S. Ill be getting my car back from the repair shop this week, as i jump with joy. Ill post pictures of the whole process of repairs.

 

This would probably be my next mod in my 5AT, but without getting any solid info, i am really worried about trying it.

 

a little off topic but if your looking for the fd I have one for sale.
https://my350z.com/forum/showthread.php?t=139073

 

I have never heard of it being done but the people that switched to the 3.5 on their 5at's seemed to have rave reviews. I think people who do FI like to switch to the lower 3.35 or whatever the 5AT is; so you may be able to find someone who will do a swap with you.

 

Thats my understanding too. I think the 3.9 would be way too aggressive for the 5AT.

 

what gear set is in the 5AT?

 

ok finaly took some time and did more re-search. Found that the 5AT has the 3.3fd and should upgrade to the 3.5 not 3.9

So now i guess ill need to find the 3.5 w/LSD pumpkin. Ill try to install myself.

James

 

How much of an improvement would the 3.9 be in the 5AT though..

 

Subscribing.

 

sq40, From what im reading, that the 3.9 in a 5AT would be to much.
I look at it this way,
6MT has 3.5 FD upgrade to 3.9FD
5AT has 3.3 FD upgrade to 3.5FD

 

im interested in this also.

why would the 3.9 be too much on the 5AT's? 3.3 to 3.5 doesnt seem like its worth the hassle. 3.3 to 3.9 is a whole new story. am i right or am i missing some info?

 

As soon as Tonio gets his car out of the shop, I will be swapping his 3.5 FD with my 3.3FD. I also have the Vortech so I am very anxious to see what results I get in the 1/4 mile.

 

Don't swap gears. Swap the whole pumpkin. If you swap pumpkins, it's a bolt-on modification. If you just do the FD gear, you have to build the gear-set. I have read where installing the 3.9 FD renders your cruise control inoperative, so think twice. If you think you'll go FI in the future, you might consider staying with the 3.3 FD... You'll want the 3.3 FD back in a hurry if you go FI.

 

I have read several posts in another thread that say if you are a 5AT and go FI, then you will want to go to the 3.5 FD if you will have LESS than 400RWHP. SO, since I am ONLY seeing around 340RWHP, I am doing the swap to see what it will do for me!

 

i usually stick to electronics, so im not understanding the whole pumkin thing. is it the bubble looking thing that houses the rear diff? how much would this whole process cost?

i dont use the cruise control anyway, so thats not a biggie. i wont be going with FI ever, im sticking with nitrous.

now if i swap gears, ill lose top end right? as in my top speed will be less?

 

Mysunset, yes the pumpkin is the housing with the gears, between the main drive shaft and the side drive lines. Going with the pre-assembeld pumpkin it is a easy bolt on. The pumpkin i seen online cost about 1,300 or so for 3.5FD w/LSD. But would be easier to go that whay if you do it yourself.

 

The pumpkin is the big bulge in the rear end. If you can find someone with FI that is local to you and is willing to swap, you will only have to pay the labor to do the swap. When me and Tonio do our swap, we will be paying around $100-150 each and thats it.

If not doing a swap, go wo www.car-part.com and look for the CARRIER assy. Thats what you need. Several guys on here have bought used ones for under $500.

Lastly, from what I hear, you will lose your top end speed. But who really needs to go 150 anyway?? IMO, its not how fast you go, its how fast you get there!

 

5AT pumkins won't be able to use aftermarket LSD's, just the factory VLSD and I think maybe cusco or someone offers an LSD specifically for the 5AT pumkin

 

Where did you hear that cruise is inoperative??? There would be no reason or this because the speed sensors take their info from the speed sensors on the outboard axles. Think of it like putting cruise on in 5th gear.

 

arent '05 g35x 3.5 already ? if swapping pumpkins, what car should i get 1 off from, 350z or G coupe?