Yes, I know the standard 'fix' is to do the 6-speed manual transmission swap, but I investigated another option today.

I called the transmission shop where I have taken vehicles in the past to ask a question. This is not a national chain transmission shop, but rather a local, well-respected shop that many engine shops refer customers to for tranny work. I asked whether the 4th gear alone could be swapped-out in our cars.

As many of you know, 4th gear in the 5-speed automatic transmissions in our cars really sucks. 3rd gear has a 1.021:1 ratio, then in 4th it drops to 0.653:1 (0.727:1 type-s), then finally in 5th it goes to 0.470:1 (0.520:1 type-s). So, in 4th gear you are already into a substantial over-drive situation, which is meant for better gas mileage, not performance.

So I thought to myself, "Self, I wonder if it would be possible to swap-out just the 4th gear with a better-adapted gear that has a closer ratio?" The short answer is 'yes' according to the transmission guy.

He said that Honda trannies (no, not chicks w/d!cks) are one of only a few manufacturers (including Subaru and some Saturns) that use gear-on-gear technology in their automatic transmissions. From my understanding, this means that Honda/Acura automatic transmissions are built like manual transmissions in design, but operate as automatics. This is one reason that they are more expensive to work on. Being designed that way, he saw no reason that a specific gear (like 4th gear) could not be replaced. Of course procuring that gear could be a challenge, but if obtained, he said it could be swapped-out.

Labor would be intense, though, as he said rebuilding a Honda tranny takes 18-20 hours. He added that there would be other supplies needed such as gasket kits, internal filter, etc., but it is all doable if someone wanted it done. At $50/hr, that would be around $1,000 just for labor, plus supplies and of course obtaining that new 4th gear...somehow.

This may not be a viable option, but I thought it was at least interesting.

 

if you are that desperate for a different gearing, go buy a used race car and take it to track days for some real fun
You can get a decent racer for the price of screwing around with the TL

 

you change 4th you might as well change 5th. The jump from 4th to 5th would be unbearable. 4th isnt that bad if you manually run 3rd to redline, you stay in vtec once in 4th and the acceleration isnt that bad.

And yes, the honda auto is a 3 shaft design that is just like a manual trans.

 

^ wait there arn't any engagement of meshing gears in the auto right? kinda hard to picture an auto set up like a manual, meshing gears just come to my mind.

 

If it'd cost approx a grand, why not put that money into a fund for 6spd swap? And get the full performance throughout all the gears

 

Not desperate...just curious.

True about 5th. Yeah, I know about redlining in 3rd, but I hate to redline if at all possible.

I don't see myself doing either at that price. I was just curious as to whether it could be done. However, changing the auto would be less invasive than the 6sp swap, and I drive in too much rush hour traffic to enjoy the manual anyway.

Another option would be to change the differential, but that would affect all gears and still require a rebuild. I guess I'll just enjoy running 3rd gear up to 70 or 80mph, then hope I'm ahead.

 

Why not, you arent going to hurt the motor.

 

how so? i thought redlining was not healthy for the engine.

 

Because we have revlimiters to keep us from harming the motor.

 

^ You'd just bounce off the rev limiter. It won't go high enough to harm the motor.

 

It might not break on the spot - first time or fiftieth time - but probably shortens the overall life of the engine. You gotta figure any engine has a finite number of RPMs in it, so you would reach the engine's end-of-life faster the more often you rev it that high. You would also have to do valve adjustments more frequently if you redline it often.

 

Ummmm No. The whole point of the rev limiter is to protect your motor from going to far. You wont hurt it. Mine hits it many times a day. (1st gear comes so fast with the 6 speed its not funny, plus on track days) I havent needed a valve adjustment in the 340,000 miles of driving yet, nor have i taken any life off the motor. If it was bad for the motor to rev to the revlimiter they wouldnt build the motor to do so.

 

That's true.

I can't believe you haven't needed a valve timing in that long. I've had to do it twice since I've had the car.

 

I should have added the first motor didnt need it when i pulled it out for the swap at 220k, this motor has near 200k on it and doesnt need it either. (though i did check them one day and they were all in spec)

 

Can we send you the bill if we throw a rod? Seriously, what was wrong with your first motor that required a swap? Too many redlines?

 

I know you did the 6-speed swap as well. Did you kill an automatic first? I know they are more fragile, so redlining might put them in further jeopardy.

 

Nothing was wrong with my motor, i wanted the type-s motor.

I went thru 5 trans. Redlining them had NOTHING to do with them failing.

Nor is it going to cause you to throw a rod

 

That's right, you did the 6-speed swap and the engine swap at the same time. I don't doubt anything you've said, but I just have a fundamental problem (fear) redlining. When I did my post-Sea Foam blow out run, that was the most I have probably ever revved a car in my life. But I must say it was fun to see how fast my car could go in 3rd gear. It definitely gave me more confidence to rev 5,000+.

I also enjoyed toasting a riced-out Prelude from a traffic light later that day He never saw it coming from my stock TL-S. I would back off, and he would try to pass...I don't think so.

 

LIke i said earlier, if it was bad for the motor they wouldnt have designed the motor to let you go that far.
Go out and play, its a HONDA, They love to Rev HIGH!