Boosting a 5AT?
#1
08-19-2009, 10:16 AM
Boosting a 5AT?
Now guys, I know a lot of you will say don't bother if its not a 6MT but I want to hear from the guys who have done it and what kind of gains they've gotten. Does it mesh well with the auto trans? I know the gearing of the 5AT is substancially taller than the 6MT since having the extra gear allows for a shorter gear. Just give me some basic input and we can go from there.
#2
08-19-2009, 06:13 PM
I had the weaksauce stillen s/c on for allmost 30,000 miles and now the greddy twins on for about 28,000 miles and my trans is holding up quite well.You must have a decent size trans cooler and at least a valve body mod or it will def fail.
The biggest thing with the 5at is make sure when you get on it you are in the right gear and dont leave it in drive as the downshift will be harsh and shock the hell out of the trans.
The biggest thing with the 5at is make sure when you get on it you are in the right gear and dont leave it in drive as the downshift will be harsh and shock the hell out of the trans.
#3
08-19-2009, 10:42 PM
#5
08-20-2009, 08:08 AM
Registered User
Join Date: Apr 2005
Location: Houston
Posts: 260
Likes: 0
Received 0 Likes
on
0 Posts
#6
08-20-2009, 09:15 AM
Thanks for the input guys. I've been looking at the Greddy twin kit and I researched the Transgo and just by chance one of the installers (Brwn5454) is in on this thread. I'm not exactly how the tranny cooler mounts, does anyone have a pic of what one might look like? Just to double check, you guys are running 100% stock internals? Even if you have a plenum spacer can you please clarify?
#7
08-20-2009, 11:20 AM
Trending Topics
#8
08-20-2009, 03:16 PM
Registered User
Join Date: Apr 2005
Location: Houston
Posts: 260
Likes: 0
Received 0 Likes
on
0 Posts
I am running stock internals, correct. I do have a tranny cooler to help with the TX heat....it is mounted to the left side of my intercooler....B&M.
http://www.bmracing.com/PRODUCTS/Aut...BTU-11x6x1-1-2
http://www.bmracing.com/PRODUCTS/Aut...BTU-11x6x1-1-2
#9
08-20-2009, 04:39 PM
Guest
Posts: n/a
Are you saying as you are coming down from highway speeds not to leave it in drive because the 5-4, 4-3, 3-2, 2-1 shifts will be too rough? It's actually better to manually downshift the trans? It seems rougher to manually downshift? My 5-4 shift at around 30mph is quite raunchy, but it was also a little rougher in stock form. I actually remember asking about it when I first bought the car. Did you mean don't leave it in drive while upshifting (accelerating)?
Clarify, "Make sure you get on it in the right gear"... highway pulls at 70mph in 3rd instead of 4th? It wouldn't even let you go into 2nd at that speed, so no worries there. Or are you talking about boosting in 5th? I know a lot of guys, mainly 6MT, don't like boosting in 6th because it's overdrive and not meant to be boosted in. Or are you simply referring to being aware of not putting too much load/strain on the engine/trans for a long period of time... say climbing a long slopping hill in 5th and almost in boost but not really accelerating?
Not trying to stir up anything, but like I said, I've had my built tranny for about 2 years now and around 10,000 miles. I'd like it to last so I always be sure I'm treating it the right way!
And as to not ignore OP, there is good info here and found elsewhere on the forum. There are quite a few boosted 5AT's that are doing just fine. Once you get a cooler and valvebody upgrade you'll start getting cocky that you can chirp 3rd every time without missing the shift while sipping on your coffee... let's see those 6MT's do that
#10
08-20-2009, 05:16 PM
Damn, after boosting you guys are actually getting rubber in 2nd n 3rd? Thats pretty impressive! I'm really looking into this seriously, I actually had the phone number dialed today to purchase a TT kit but backed out because the wife came home early and I got distracted. On another note, how much would the transgo kit cost me in labour to have installed? In Canada, we don't have too many G35/350 specific shops or that are very familiar with them. The ones that are absolutely RAPE you in price, I was considering Mr. Transmission or something along those lines since they would be able to provide me with warranty, what are your guys' thoughts?
#11
08-20-2009, 06:29 PM
Being a ProCharged 5AT (350whp, 320wtq) with a built tranny from SGP (my second trans after the first one blew from being kept stock) I always try to follow up on these kinds of topics to see if any new info has come up... and this is the first I've heard about not to leave it in drive while down shifting.
Are you saying as you are coming down from highway speeds not to leave it in drive because the 5-4, 4-3, 3-2, 2-1 shifts will be too rough? It's actually better to manually downshift the trans? It seems rougher to manually downshift? My 5-4 shift at around 30mph is quite raunchy, but it was also a little rougher in stock form. I actually remember asking about it when I first bought the car. Did you mean don't leave it in drive while upshifting (accelerating)?
Clarify, "Make sure you get on it in the right gear"... highway pulls at 70mph in 3rd instead of 4th? It wouldn't even let you go into 2nd at that speed, so no worries there. Or are you talking about boosting in 5th? I know a lot of guys, mainly 6MT, don't like boosting in 6th because it's overdrive and not meant to be boosted in. Or are you simply referring to being aware of not putting too much load/strain on the engine/trans for a long period of time... say climbing a long slopping hill in 5th and almost in boost but not really accelerating?
Not trying to stir up anything, but like I said, I've had my built tranny for about 2 years now and around 10,000 miles. I'd like it to last so I always be sure I'm treating it the right way!
And as to not ignore OP, there is good info here and found elsewhere on the forum. There are quite a few boosted 5AT's that are doing just fine. Once you get a cooler and valvebody upgrade you'll start getting cocky that you can chirp 3rd every time without missing the shift while sipping on your coffee... let's see those 6MT's do that
Are you saying as you are coming down from highway speeds not to leave it in drive because the 5-4, 4-3, 3-2, 2-1 shifts will be too rough? It's actually better to manually downshift the trans? It seems rougher to manually downshift? My 5-4 shift at around 30mph is quite raunchy, but it was also a little rougher in stock form. I actually remember asking about it when I first bought the car. Did you mean don't leave it in drive while upshifting (accelerating)?
Clarify, "Make sure you get on it in the right gear"... highway pulls at 70mph in 3rd instead of 4th? It wouldn't even let you go into 2nd at that speed, so no worries there. Or are you talking about boosting in 5th? I know a lot of guys, mainly 6MT, don't like boosting in 6th because it's overdrive and not meant to be boosted in. Or are you simply referring to being aware of not putting too much load/strain on the engine/trans for a long period of time... say climbing a long slopping hill in 5th and almost in boost but not really accelerating?
Not trying to stir up anything, but like I said, I've had my built tranny for about 2 years now and around 10,000 miles. I'd like it to last so I always be sure I'm treating it the right way!
And as to not ignore OP, there is good info here and found elsewhere on the forum. There are quite a few boosted 5AT's that are doing just fine. Once you get a cooler and valvebody upgrade you'll start getting cocky that you can chirp 3rd every time without missing the shift while sipping on your coffee... let's see those 6MT's do that
#13
08-21-2009, 03:55 PM
I've coming up on 30k boosted miles on stock motor. In January (6300 miles ago) I had a fully built tranny done and a valve body done by SPG. I could not be happier with the way the tranny shifts and I have no doubt it will hold whatever I throw at it (I'm hoping to get high 400 at some point).
Make sure you get a tranny cooler put on ASAP at the very least. I have an 11 x 11 x 1 1/2 inch tranny cooler on. The one listed in this thread is tiny and IMO too small. I had that exact one actually and the tranny went into limp mode due to overheating at the track. I used this cooler:
http://summitracing.com/parts/BMM-70274/
Make sure you get a tranny cooler put on ASAP at the very least. I have an 11 x 11 x 1 1/2 inch tranny cooler on. The one listed in this thread is tiny and IMO too small. I had that exact one actually and the tranny went into limp mode due to overheating at the track. I used this cooler:
http://summitracing.com/parts/BMM-70274/
#14
08-21-2009, 11:11 PM
.
