Hi everyone,

I will be turbochargine my engine shortly.... finally got all of the parts for my custom kit, but unfortunately I am running into problems with my 97 ITR tranny. The 3rd gear synchro is really bad and grinds every time I try to put it in 3rd. I will be rebuilding this tranny, but I was wondering if it would be a good idea to swap the 5 gear from a LS tranny??? This would help out with higher top speed as well as better rpm range for driving on the highway. Is there any disadvantages to this? Will this actually work???

And would anyone have a spare LS 5th gear?

Thanks

 

Not sure if it would work but i do know of someone with a ls tranny that might be for sale.....It has a bad 3rd gear synchro. If it works pm me and i will ask him.

 

The gears are transferable, only problem I forsee is if you are racing you pretty much have to stop after 4th gear otherwise you drop out of your powerband, it will stil accelerate but not to racing duties.

If you're a 1/4 mile nut then if will be fine as long as you choose your tire size well so you won't run out of gear at the end.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Screamer &raquo;</TD></TR><TR><TD CLASS="quote">Hi everyone,

I will be turbochargine my engine shortly.... finally got all of the parts for my custom kit, but unfortunately I am running into problems with my 97 ITR tranny. The 3rd gear synchro is really bad and grinds every time I try to put it in 3rd. I will be rebuilding this tranny, but I was wondering if it would be a good idea to swap the 5 gear from a LS tranny??? This would help out with higher top speed as well as better rpm range for driving on the highway. Is there any disadvantages to this? Will this actually work???

And would anyone have a spare LS 5th gear?

Thanks</TD></TR></TABLE>

it will work.. i drive type r with type r gearing.. and getting ls 5th gear would make everything retarded.. it works great as it is.. my car don't make much at low rpm so whats the point of lower rpm....

 

Thank you for all the comments.

vtec.dc2 - your car don't make much of what??? I don't quite understand your answer. Can you please comment on what you mean.

Just for information I am estimating my power output to the wheels at about 400hp. Therefore there should be no issue with droping out of power band in 5th, but it should help out with top speed right???

Has anyone actually done this gearing setup???

 

keep the type r tranny..leave the gearing alone..rebuild it..it'll be fine for what you're doing.

 

Thank you for your comments, but I still have not received an answer to my question. Will this modification allow for better highway drivability and will it increase the top speed???

Anyone?

 

It will "allow" higher top speed, but only if you plan to open it up past ~150mph (approx) where the ITR 5th gear redlines. It may help increase gas mileage, if you care...

 

Hmm... I guess than the top speed is not really an issue, but the milage is. Would anyone know where does the LS tranny in 5th gear rev at 60 miles/hr???

 

bump for you.

 

about 3100-3200 rpms

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Screamer &raquo;</TD></TR><TR><TD CLASS="quote">Hmm... I guess than the top speed is not really an issue, but the milage is. Would anyone know where does the LS tranny in 5th gear rev at 60 miles/hr???</TD></TR></TABLE>

You'd need to change the final drive too, to a 4.4 to a 4.266 to get true LS gearing in 5th and that'd mess up all you other gear ratios. You probably only loose 1mpg, if that, by reving higher, i still get 26MPG on my LS with ITR tranny and that tank i used half a bottle of nitrous. So i probably get 30 if driven nicely. You'd probably be better off making sure your tires were fully inflated... and a lot let work. If you still want to do it, a ls 5th gear ratio is .714 and a ITR is .848, i think, so it'd be about 20% longer gearing in 5th. A tranny shop would probably charge a couple hundred dollars, assuming you dropped the tranny and brought them the gear. I'd think that if you are concerned about gas milage, you drive cross-country on the money you saved... literally. Actually twice.

And to answer you question, it will help drop the RPMs in 5th. It'll slow you down slightly in the quarter though since you'll shift from redline to like 4500 or something. It will also increase your top speed, but that shouldn't be too much of an issue cause if you have an LS your top speed w/ ITR tranny would be like 126MPH... which is pleanty for me.


Modified by Cyphear at 9:59 PM 8/12/2003

 

Thanks a lot this is exactly the type of answer I was looking for. I guess I will be sticking with the ITR gearing for now than... who really cares about milage anyways right . LOL... if you go turbo power is where it is at

Thanks for the great reply.

 

the reasoning why many switch trannies is due to the short gearing to stay in powerband....in a Fi car many have seen videos of 400whp cars getting screwy and ripping thur 6000+rpms....in the blink of an eye....w/ the ls tranny youd have talller gears allowing your turbo to work a bit more....yes youd fall out of powerband, but if you designed your setup to accomedate this you in essence could have a larger powerband w/ **** loads of power.....there is a guy in the itr forum who has something like 400whp and has such tall gearign he can do something like 205 in 5th....so....also dont forget torque of the motor is multiplied thru the tranny....more torque = less traction.....less traction = less go esp on a street ride

 

why not just use ls final drive to lengthen all your gears? wouldn't that benefit you as you have all that power to spare?? 400hp is a grip load of power...giving it a little more room wouldn't hurt.

 

Yes, you guys are both right... unfortunatley my car is not turbocharged yet, well at least for the next 2 months. For now I think I will stick with the stock ITR gears. If that does not work out too well I will try to play around and get new gearing, maybe do the LS final drive... I don't know yet, but thanks for great input.

 

no prob...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Screamer &raquo;</TD></TR><TR><TD CLASS="quote">Thanks for the great reply.</TD></TR></TABLE>

I'm happy to help. I'm in the same boat actually, but i'm not considering switching to longer gearing. I'm running a B18B with ITR tranny and collecting parts for boost. In my unscientific opinion, i think the shorter ITR gearing is probably best for up to a 11 second car or so. After that you are acellerating so fast that shifting isn't worth the time.

Keep in mind, bigger tires and higher rev limits effectivly create the same effect as lengthening gear ratios.

 

Yes, you are right, but the larger wheels and tires combo also comes in at a cost . And that is not only as a financial cost but lower profile tires reduce the traction. Anyways... thanks for the info.