Mazda3 Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
320 Posts
Discussion Starter · #1 ·
Putting this here since it's more a general power mod question than a boost specific one. I am doing the background upgrades to my '3' sedan so that later I can boost. One of the upgrades that I've seen on this forum is to upgrade to a LenTech valve body, but I don't quite understand why. I understand that the new valvebody will change the shift points, and make the shifts quicker/more positive, but I can't figure out how this might allow the transmission to handle heavier power loads. Seems to me that you'd have to upgrade more than just the VB, say the input/output shaft, to handle a lot more torque.

Anybody know the answer?

Thanks in advance!
Rick "Weeble" Fogle
 

·
Registered
Joined
·
501 Posts
I can't answer your question fully but, i can help. A valvebody controls the flow of the fluids in the transmission and a new one can increase that flow and not only make better shifts but, will make the transmission engage the clutches harder and cause it less likely to slip under heavy loads. You are right that it doesn't physically make the transmission stronger i.e. able to handle extreme modifications and hard drag launches all day. In the end the valve body will allow your transmission to handle more power and more abuse without burning up the clutches. I don't know what the limits are of the automatic transmissions in the mazda3 i bet it is pretty strong since some people with ATX have boosted and survived. I'm sure that someone else has a better explanation but, that is what I know a valvebody does.
 

·
Registered
Joined
·
320 Posts
Discussion Starter · #3 ·
Thanks Adam, that cleared it up a bit - the VB will help me not burn up the clutches, but won't keep me from twisting the shafts or shredding a gear.

As far as the strength, I seem to see a lot of opinions that our ATX, especially the 5-speed ATX, is relatively weak. I know that the Reactive Racing turbo kit has been used on an ATX successfully "as long as you don't do something stupid", which I'm guessing means no hi-rev launches, or two-gear upshifts at 50 mph. They run 6 psi on that kit with stock engine internals.
 

·
Registered
Joined
·
3,404 Posts
the valve body and probably more importantly, upgraded solenoids, allow the clutch packs to engage and disengage more rapidly between shifts. this prevents slippage, which is the main cause of automatic transmission failure. the gears and shafts are not likely to fail, which is why they are rarely replaced. aminzer also upgraded his torque converter when he had his trans built, allowing for a higher stall speed. stall speed is the rpm at which the torque converter locks, transmitting 100% of the engines torque to the input shaft.

and on a side note. there is the 4speed and 5speed ATX. LevelTen makes the upgrades for the 5 speed, and lentech makes then for the 4 speed. the 4 speed is stronger in stock form than the 5 speed.
 

·
Registered
Joined
·
2,626 Posts
good info! :stirthepot:

Since we are on the topic of upgrading an AT; I have not seen one person on here upgrade the tranny but still staying N/A.

Is it because it'll be a waste of money to upgrade the tranny and not boost, or just personal preference?
 

·
Registered
Joined
·
320 Posts
Discussion Starter · #7 ·
Thanks Verto, you anticipated my biggest problem which is that I've got a 5 speed ATX so I'll check out the LevelTen site now. Staying NA we're not going to get enough balls out of our engines (I think the most I've heard of is high 160's or so) to make the trans upgrade vital, but even on a stocker they'd help increase the lifespan.
 
1 - 7 of 7 Posts
Top