Best upgrade

[BAC5.2]

Dog boxes generally have no, or partial synchros.

http://www.turboxs.com/turboxs_dog_box.htm

Vikash - Could you do some high-level manual tranny descriptions, at least for my benefit. You can either post here, or send me a PM when you get a chance. I'm very interested, and I know far to little about a manual tranny.

[legacy92ej22t]

Vikash - Could you do some high-level manual tranny descriptions, at least for my benefit. You can either post here, or send me a PM when you get a chance. I'm very interested, and I know far to little about a manual tranny.

I would really like that also but I'd like to see it in a seperate thread in the Drivetrain forum. That way when people are searching that forum they'll come across it and if it's really informative then it would make a great sticky.

[tris91ricer]

I'm in on that one, too. I nice 5MT primer would be kinda coool... perhaps that Marshall Brain website --uh, www.howstuffworks.com
dunno what they have on that.. only autos, i guess.. but knowing the what/how/why things work the way they do in there would be kinda nice.
I'll even help research, if you don't want to do it all by your awesome lonesome.

-=tris

[tris91ricer]

oops. i think i FUBAR'd that one...
http://auto.howstuffworks.com/transmission.htm
could we still get a legacy tranny write up then?
pwetty pwease?

-=tris

[vrg3]

Wow, I don't know how I missed that HowStuffWorks article. That's really good.

I don't really know much about how the Subaru transmission differs materially from the norm. But I'll come up with a really short primer on manual transmissions and how shifting works and post it in a new thread. Then everyone can add their knowledge to it and it'll end up as a good reference thread that we'll always link to whenever anyone asks a question about gearboxes.

[legacy92ej22t]

Ya, that "how stuff works" write up was nice. I love that site. They make thing very easy to understand.

[evolutionmovement]

That site's the next best thing to tearing something down.

Steve

[-K-]

I thought 98 RS would have the newer tranny?
Have you looked at the Subaru top mount Air to Water Intercoolers? It's a great set up and with a new turbo it wouldn't be hard to set up. I'm real happy with mine and the guys from Austraila where they get them stock say they are good up to 250hp.
My syncros are going as well but it's a wearing part that won't last forever. Mine was driven with a bad clutch for a while before I got it I think and that's what did the damage.

[dzx]

I think im going to go with a TDO5 16G turbo and a spearco front mount intercooler, at the same time get a ecu upgrade and see what i can do about the fuel needs. I also have to go pick up some 17" prodrive rims that i bought last week. Anybody have suggestions on a good loud BOV for not too much?

[-K-]

Sounds good, though I'm not a huge fan of Mitsu turbos spool up time, they make great power.
Fuel: I have thought of the WRX manifold, don't know if it would fit up right, might try when I get home. I also might just modify my manifold to use standard Bosch injectors, being a machinist it should not be hard for me. Kelly is also working on fuel rails for us, I might just wait for them.

[musketeerracing]

Missed this thread for some reason. Here's the gearbox skinny:

First thing to always remember: All your forward gears are always in constant mesh. When you shift, you don't cause gears to run into each other. You cause them to lock onto the shaft that otherwise they would spine freely on.

You lock them onto the shaft with a slider that has some sort of teeth on its face that interfaces with the SIDE of the gears. Dogboxes ans syncro boxes both have these teeth.

The real difference is that dogboxes have like six big chunky teeth on the side of every gear and slider, while sychro boxes have a lot of little teeth and two cones that work like your clutch does to matcht the speed difference between chaft and gear like your clutch does for flywheel and input shaft.

Most dogboxes have straight-cut gears. Helical gears - quieter because as they mesh they hit each other on an angle - are the norm in street cars. But straight cut and dog engagement are completely seperate things. (The only relation between them is that helical gears create a lateral load on mesh that can make dog engagement more tricky).

YOU DON'T NEED TO DOUBLE CLUTCH A DOGBOX. IN FACT THAT'S EXACTLY WHAT YOU SHOULD NOT DO. I don't know why people keep thinking this. Dogboxes rely on extremely fast shifts so that the teeth fall into each other rather than skipping across each other. The whole point of dogboxes is that you really don't need to use the clutch at all - just unload the input shaft and click to the next gear.

That said, I think dogboxes are pretty stark for street use. Everything about them is the opposite of synchro boxes: they RELY on extremely fast shifting to be smooth. I have a serious Hewland dogbox in my Evo, but my 5MT in the LEgacy will do me just fine on the street, thank you.

ACP