i am planning to build a reacing gearbox for a long time. but still i coulnt decide. there is some kinds like helical or strait cut gears, sequrential or not. i know that these gearboxes can be used with or without clutch which affects gearbox life. anyone have experience?

it really depends the sequential gear box that would be available to us would still require the use of clutching although changes would be made by and up/down only motion...

i've been looking into these transmissions here
http://www.xtrac.com/mainindex.htm

you mean like a ratchet shifter?

only 1 of these was ever made in the world to fit a 6gc

but my previous post refers to an actual transmission

tuffy have you ever driven an SMG M3?

no i didnt
i know that fensport make one for 3sgte 4x4 gearbox they sell it for 5000 gbp. they use this on 7 th gen celica project.

if you ever get the chance try going to your BMW dealership and test driving a SMG M3 you'll get a good feeling for wat an ELECTRONIC controlled sequential gear box is like..

but like i said if you check out that Xtrac company their history and accomplishments look pretty good and they offer a wide variety of gearbox setups for different types of racing, and they also offer a 6spd in most cases, i'm not sure how the GT4's gearing is but having the ability to select your gear ratios is an incredably appealing piece to me.

but good luck i hope i provided you with something helpful

thanks for good info m8 ii make some more investigaton

Straight cut offers better power transfer and durability when done correctly. Can be noisy as hell though. Helical gears are quieter and with all the modern advances in metal tempering can be made almost as strong as a square cut set. They will destroy fluid faster due to a smaller transfer surface, and without proper changing of fluids or contamination you will get surface chipping.


We have a 5088 IH (yes I work at ag parts, big toys store) torn down in the shop as the heli-cut pinion was shreaded after the surface chroming came off and ran through the gears a few times.

I've always like the turbo 400 Rock Crusher for Chevy engines. It's strait cut. If I were to build a transmission for the car, I would want strait, no matter how noisy it was. It's just going to wine anyway, and that's a cool sound. It is if you know what it means, rock solid transmission. With the AWD, and putting out as much power as you are planning too, I don't see how you could go any other way if you wanted a really reliable transmission. Oh and btw, 6 speed is over rated. Save yourself a couple thousand euro and just get a 5 speed.

if your going to claim "6spd is overrated" why not back up your comments with supporting evidence?

i can see 6spds being very practical depending on the selected gear ratios that he choses and what kind of driving he is after

making blanket statments without evidence is stupid

If you are drag racing, or autox racing, or pretty much any racing other than big rallies and top speed competitions, you don't need that 5th gear. I bet the built gt-4 doesn't even go out of 4th in a drag. How often do you go over that speed anyway? And, for a boosted motor, you'll have more power through the power band if proper turbo set up. NA needs a 6 speed more because it's harder to keep power on with the cams you have to run with high hp NA set-ups. 6 speed is cool, and it's good for mileage, but it's not god-like. That's why I say it's over-rated. Heck, I use to think I needed a 6 speed in my Mustang. But 5, or even 4 for it, is just fine. That's why, on a properly tuned boosted motor, a 6speed is more for bragging rights than practicality in most cases. If you're really going to use it, go for it. But don't feel like you have to get one.

Playr158, you are an asshole. I'm sick of you. I'm sick of what you do on this board. All you do is try to piss off people. If I had my way, you would have been banned a long time ago. Sure, you do have a nice car, and you've made some nice contributions, but I'm just sick of your mouth. If you weren't some pussy ass internet punk, and where were I could get to you, I would honestly kick your ass. Eat ****, man.

Moderators do whatever you have to me for saying what I did, I'm sick of him, and he needs to know it.

glad you think i'm an ass! really doesn't matter to me...

i just was curious why you thought 6spds were overrated..
now if you think that was an asshole comment, you need to get outta the carebears club and back to reality cause i'm pretty sure i havn't gone to piss anyone off in this thread...if you want to talk to me PM it, don't trash a thread

but on topic

drag racing i only see 4 gears being used in total
but if your a road coarse racer 6 gears depending on gear ratio and a few other things can make a difference...and if tuffy is driving the 4 around town...maybe a 6th gear would be nice to save gas...
nobody here is praising 6spds....

i found a guy on google that made the sequential for the rally purposes, i don't know where it was i can't find it all though it was good, it was electronic shifter and everything the whole 9 yards

the two of youz need a hug...and tufy needs to give me his car

racing trannies are not good for daily driving. Why? Just trust me. It'll take too long to explain.

ok...
is it some think like
racing clutches are not good for daily drive..
big turbos are not for daily drive....
harder suspensions are not for daily drive...
light weight flywheels are not good for daily drive...
higher duration cams are not good for daily drive...
etc..etc..etc
i wanna know the reason.

I have just one in my mind...

racing part is "prepaired" for short but extreme effort, daily use is long but low effort (example from athletics: world's best 100 meters runner will not be best marathon racer). I belive I'm not far from true...

malpaso you prove a good point. the way the interact and wear is very different from something thats ment for higher reliability and prolonged use where all the parts tuffy stated are more frequently replaced (with exclusion of cam and turbo) as they experience more/faster wear

but those pieces decrease the ability to "easily drive" the vehicle...clutch points become more "on/off" and less able to slip...idle is going to be more touchy and ruff....ect...its more the ability to drive the car with the modified parts becomes harder and harder on the street...thus not as comfortable as a daily driver should be

Just imagine your driving in traffic (If there is any in Cyprus) and need to rev the engine to 2000-2500 rpm otherwise the engine will stall. Thats my experience with a "on/off" clutch.

Have driven a race/track/fun car some guys build for fun but to use that on a daily basis...... nope.

Clutches are something I think most know about. The transmission isn't though. I think Kwanza was proving a point with his statement, or he would have explained. I think if you build it right, it should be good for most anything. A racing auto isn't as good as a street auto, but I don't know why, other than noise, that a heavy built transmission would be bad for dd car. I think it depends on what you call a racing transmission. It would be nice if you would elaborate a little bit Kwanza. I'm pretty curious about this.