I am having some trouble with deciding on a transmission and woul like some experienced input. I have a rb30 making 300rwkw and i need a transmission for it. I look at having a stronger tune soon for the track hoping for 350rwkw. Due to it being a street car predominantly, im thinking of going back to the 4 speed jatco w all bells and whistles tbrake etc for the few times i want to go to the track and also just for the ability of overdrive etc for road use. I want to steer clear of a powerglide as it is not making good enough power to require one, and im torn between a C4, TH350, TH400 or just getting a 4 speed jatco as the amount of times ill run it im sure it will hold the power fine. Thanks.

C4 man. Can't go wrong, and will be fine for road use unless your planning on driving from Melbourne to Queensland. My car has a glide with a 5500 converter, locking up at 4600 with the old combo and sat on 3000 @ 110kmh, I'm pretty happy with that. A c4 will see similar depending on converter choice

Why not go JATCO 3 speed instead of the 4? Think they can be built a bit stronger then the 4 speed... Plenty of places with good reps that'll build one for you.. Als Race Glides Preston Automatics & Diffs Protrans KEAS Best bet would be to call up and have a chat to them and explain to them what you're after!

yeah but the way i see it is too many people have dramas with these jatco's. So why go the 3 speed when i'd go to a proven C4 for that bit extra that can actually handle 750-1000hp if the right money is spent. Not borderline hp rating for what im running. the only reason i was even contemplating the 4 speed is because of the overdrive option. I will give them a call though and see what they say. thanks

for 300kw jatco is the go, they have been built to handle this power for donkeys hell i brought one off this site to handle that donkeys years ago. Stay away from any of the gm boxes (t350, 400etc) the will suck way too much power for what you want. with that power you have an awsome street car are you against manuals? an r33 5speed would be perfect.

Mx7 ?

mx7 or r33.. happy days

You completely contradicted yourself... If you don't want something thats "borderline hp for what ur running" then why not just go glide? Would be the toughest, and cheapest option of anything bar JATCO.. With the most available parts etc. :S

powerglide, C4, TH350, TH400 all have 1.00:1 top gear, Jatco is closely based on a C4 but with mostly roller bearings compared to bush bearings.

maradine make a killer fan you can normally get them from jas ociania

i would like to retain a 3 speed or 4 speed though, as i want it snappier off the line. I am pretty likely to go a C4 from the states.

I'm with AVG45 100%, dont muck around with a jatco. If you decide to get more serious with it down the track then you will have only spent your money once. If you'd prefer a 3 speed over a glide then just go C4. A guy here in Canberra got one from the states with all the fruit and cost him half price by the time it was in the car.

Quote: Originally Posted by vin-vlt [View Post] i would like to retain a 3 speed or 4 speed though, as i want it snappier off the line. I am pretty likely to go a C4 from the states. Snappier off the line with 350rwkw? The only thing that will make that snappier is a set of slicks. People wanting a 3 speed always say they want a shorter first gear but in all honesty with that kind of power you never use first to anywhere near its potential on the street... it just wont hook up.

^^ yeah that's it. Wat sort of power is your car making progmh? And you run a glide aswell? Don't no wat yours is like but my car on run in tune made 260kw on 14psi and was in 2nd/top gear in an instant, so vin-vlt if you are going to be making 300-350 then with the right converter choice it will be a good car wheather it's a glide or C4. Don't be scared of the driveability of a glide!

Nothing wrong with a built 3 speed jatco. Especially on slicks with upto 400rwkw, first gear is ur best friend !!! Especially when you're racing the big V8 boys at Powercruise who try n slow u right down for a run or if u wanna get a little jump in the off street drags. Definitely nothing wrong with a 3 or 4 speed jatco, the only benefit of the 3 being it can be rated to a higher hp rating.. Can be built here by multiple workshops using reputable top of the range KEAS components, direct bolt up, no bending or bashing and after sales support from whoever you buy from.. Something that I'd imagine would become an issue with a transmission bought from the states if it happens to have issues out of the box.

What trans to run is just a question so many guys would be asking themselves i believe. I have not heard a bad remark about the C4 (which would feel similar to a Jatco) and i have never been in a vlt with a powerglide so its a difficult decision. Just would like to keep the ratio lower for better launches and top gear is always 1:1 anyway. Just wish i knew someone in adelaid with a vlt & glide.

Endud up going a 1000hp glide with transbrake. CBF with all the Jatco dramas people have. Happy days hopefully!

Good stuff mate

Woohoo

Where did you order it from? or is it S/H?