I just talked to Jerico transmissions and got some basic info about their 5-speed road race trannies. This is the dog-ring rail-shift type with an offset shifter. Can handle upwards of 1000 hp and buttloads of torque. i.e. bulletproof for those with doubt. They will work easily with the engine. Any bellhousing can be adapted to it, including the TII. The TII bellhousing will rotate the transmission several degrees which is beneficial since it will help locate the shifter in a more central location in relation to the centerline down the transmission tunnel. This also maintains starter mounting location since the same bellhousing is used. The longitudinal position of the shifter can be located from 19-1/4" to 30" back, each + 2-1/2" if the adapter is used. Any clutch/flywheel combo can be used...as long as it is 18 spline Chrysler.
Ohhh yesss, I love left foot braking!!!

http://www.jericoperformance.com/products/rr5spd.html

Silver Kodiak, if he is around, does this all sound about the same with your tranny?

 

havnt been able to talk to my builder yet, but it does sound kinda similar to some stuff my father told me
glad you got you're info

 

Are you planning on streeting the car? Because dog transmissions like Jerichos can cost a small fortune in rebuilds.

 

****** forum, just screwed my reply for the third time

speaking of straight cut trannies, heres a picture (kinda) of Exit13b's Doug Nash sequential. He doesn't like it to much because you lack the ability to downshift and hear your engine.
Theres a vid of his car with this tranny somewhere on the forum

well since i cant ******* upload, heres a link
http://www.pbase.com/image/11900241
btw, heres a link to the local west penn rx-7 club meeting, was at sevenspeed (co-owned by exit13b). they had a 1000hp r32 there. hks t51r kai, nitrous, trust built engine, http://www.pbase.com/meanrex/feb_1_2...nspeed_meeting

 

I will be running it on the street, but very limited. Maybe as much street time as track time. I'm not to worried about the cost, I can rebuild any dog-ring tranny, they are all basically the same. The only differences are if it is a transaxle or standard box and the size of the gears. Besides, most only require new dog-rings anyways. Plus a strong box can take tons of abuse, as long as the gear oil is changed often enough.

 

If cost is no object, then I envy you! You sound like you know what you're doing though, so no worries.

 

I only sound like I know what I'm doing

 

RX-Heven are you also changing the diff and LSD, if so which ones will you be using?

 

I am using the Kaaz diff 4:10. I was going to go with the 4:30 since this will primarily be a road race car but figured that would multply any traction problems that I would have. Ari from RX-7.com and others assured me that this lsd would hold up. Actually, the diff housing would be more likely to break than anything which is more of a problem in 3rd gens than 2nd.

 

Back from the dead...

Hey Dave, did you ever get the Jerico dogbox? As you can see from this post of mine (https://www.rx7club.com/forum/showpo...&postcount=165) I've done quite a bit of research on the various trannies, and I have not come across ANYTHING that'll withstand a substantial amount of power other than the Hollinger and just now the Jerico. Hollinger has an amazing reputation, but at $10,000 for just the box, plus about another $2,000+ easy to get it to mate to the rotary, + shipping from Australia, AND their recommendation to have it rebuilt every 3,000 miles, I think it's simply more trouble than it's worth.

So I'm def. trying to get more info on the Jerico unit. They require a $2500 deposit, so I'm guessing the tranny is somewhere around the $5000 range? And did they document in writing (email etc) any solid torque rating figure for their 5-speed roadrace trannies? Also I know you said any bellhousing can be adapted to it, including the TII. Now what's this about "any clutch/flywheel combo can be used...as long as it is 18 spline Chrysler"? Not sure what that means... (Don't mind the noob )

Thanks!
~Ramy

 

Finally something good about living in north carolina. I live about 30-35 minutes away from there, so I could actually go pick up a transmission.

 

I figured I'd add that the Doug Nash design was purchased by Richmond gear, and I spoke w/ them. They rate their tranny at 450 ft lbs of torque, and have one in the test phase that supposedly will be good for 500 ft lbs of torque. Useless IMO. Ditto w/ the Saenz 910 tranny, which is good for 580 ft lbs of torque. Better, but still quite low, given that Ivan (20bfd3s) broke his stock tranny at about 680 ft lbs of torque! https://www.rx7club.com/20b-forum-95/damaged-tranny-my-20b-today-368723/

Lenco makes trannies good for over 3500 hp (yes you read that right lol) but they all use multi-level shifters. Not only nasty, but very impractical. Ditto w/ Liberty trannies; they can hold well over 1,000 hp, but apparently only use a standard sequential shifter only. No H-pattern available.

Hewland offers a 5-speed good for 600+ ft lbs of torque, which is the best I've seen (I have yet to get a quote on the Jerico tranny), AND it's available in an H-pattern (the MVE-STA tranny).

I haven't spoken w/ G-Force yet, but I will soon, although I've heard the Jerico trannies are better/stronger.

~Ramy

 

Problem I hear is that if you find one that can handle the torque, check the RPM rating.
Most of them cannot handle anything over 6kRPM...maybe 7kRPM.
You're really choking the engine is you gonna keep redlines like that.


-Ted

 

Jericho's reputation speaks for itself.
I have not looked into them for quite some time since my project was put on hold and I was not really interested in cutting up the tranny tunnel to accomodate the 5-speed tranny. The cutting to the tranny is to accomodate a box a where I like to put my leg. The external shift rails would require that but the 4-speed would not iirc. I am only interested in 5-speeds.

Sarcastic statement mentioned by the guy on the phone at Jericho. He really meant there is a limited though sufficient selection of clutch options.
They did not offer any evidence in writing of torque figures on their trannies. You can see plenty of that proof live during one of the 37 "Sunday 500" races. The trannies started around the $5000 iirc. They were quite friendly on the phone, at least the guy I talked to, and he was familiar with 20b's and even how the TII and 3rd gen bellhousings lack a few mating points with the 20b rear side housing.

Keep in mind all my info is three years old. If you do end up contacting them and getting some info, be sure to spread the word back here.

Not sure what you plan on using the car for but knowing that and your budget should help narrow your search.

 

What trannies are you refering to that are limited to 6k-7k rpm?

 

If you do get the jerico, get ready to cut your trans tunnel...

 

Well, if you're doing a 20B "right," you gotta move the motor back anyway, which means the tranny's gonna have to be moved back, so cutting the trans tunnel is inevitable. Might as well...

 

So I spoke w/ Jerico today, and on cars as light as ours (2800 lbs), they rate the Road Race 5 Speed tranny at 900 ft. lbs (at least!). It's available in a gated H pattern only (which isn't as nice as an ungated pattern, but it's a minor point). Tranny's $5,000, including the lightweight magnesium case. The FD/TII bellhousing adapter is $275, and the shifter is $795. Lead time is about 4 months. As for clutches, you can use whatever disc you want, but the plate used must be an 18 spline Crystler plate. I wonder if Exedy offers such a plate... or if they don't if they can mak a custom one

~Ramy

PS: I emailed G-Force, and have yet to hear back from them. Hope this info helps

 

Cutting the trans tunnel is not inevitable when moving the motor/tranny back...at least with an fc and no oil pan to worry about

 

Yea but I'm talking about an FD Dave And even w/o an oilpan. IMO (as there are several ways to do it), I'd drop the motor as low as possible, use a dry sump to eliminate the oilpan, and push the motor back NOT through the firewall, but through an expansion of the tranny tunnel - about 6 - 8 inches or so.

 

You dont have to cut the tunnel at all to install 20b in the FD. There are several ways of doing it. The people that move them back are doing it mostly to keep the COG intact with stock steering geometry. However, you can mount the engine with a stock steering rack, stock oil pan etc. Check out: https://www.rx7club.com/20b-forum-95/my-rx-7-done-cup-holders-3-rotor-semi-p-port-n-setup-stock-subframe-454580/

He retained 50/50 weight distribution. His COG might not be as good as some other 20b cars with lowered engines, but i doubt this makes THAT much of a difference in the driveability and dynamics of the cars handling.

My fab man also makes a 20b engine cradle/subframe replacement that is pretty trick, but not exactly cost effective. It retains the stock 20b engine and stock FD mounting locations. it is a tight squeeze, but it works.

Ill ask for pics if hes taken any.

Ramy, im excited that you are persuing the jerico option. If I could do it over, I would have ponied up the extra cash for a 5 speed. Also, remember that these transmissions are not sequential. The vertigate shifters you are talking about are for drag racing only. You cannot downshift until you come to rest, so for a street driven car it is pointless. The H pattern is fine. With the jerico, there is really no chance of missing a gear. The gates are extremly well defined. With the 5 speed, it might be a little different, but with my 4 i slam it without even thinking, and it shifts instantly (and loudly )

Are you still thinkin about checkin mine out this weekend?

bobby

 

I just got off the phone w/ G-force. Their GF-5R 5-Speed is rated at 1,000 ft lbs, 1200 hp, is good for 11,000 rpm, and comes w/ an option of 10, 18, and 26 spline clutches. Lead time is 3 - 4 weeks. It's available in both the Vertical gate (which to my understanding is what's called a sequential tranny) and an H-pattern. It's $5500 + shifter and some adapters for various bellhousings are available (I didn't ask which ones).

Oh and the Jerico RoadRace tranny is rated for at least 10,000 rpm, although he says a bunch of the Puerto Rican 20B racers launch w/ their trannies at 13,000 rpm, so I think it's good too

Bobby, yes I'm aware you don't HAVE to, which is why I prefaced my statement with "IMO (as there are several ways to do it)." But IMHO, if you're gonna do it, do it once, and do it RIGHT

Thanks...me too. Although I'm still weighing in between the Jerico and the G-force...and what clutch I can use (for some baseline streetability) will be a considerable factor in making the decision.

What's the diffeence between a vertigate and a sequential? The ability to downshift? Sounds like a drag race tranny only (you'll never need to downshift; just upshift).

Yea I'm def. sticking w/ an H-pattern, although I'm kinda curious how a sequential shifter would be

Absolutely. I'll find out today what day I'm on call (and thus what day I can meet up with you).

~Ramy

 

Ramy,

I've been holding off on some major portions of my project largely because I'd like to have a transmission choses. I appreciate all the information, and look forward to you sharing more of your results.

As for the clutch, I was hoping to used a carbon carbon varient for streetability/power handling. Do you have any thoughts on what you might do?
Any information on the dimensions/lengths/shifter placements of these options?

-Chris

 

Chris,

I'll update this thread once I've figured everything out. This is a LOT more complicated than I thought it would be...

Thanks
~Ramy

 

If you are going to go with a Jerico (they are the best for the money) call up Taylor Race Engineering in Texas (talk with Scott Young) he set me up with a 5spd for my FD (just a 13brew) if you do call him up tell him Jeff Kiesel told you to call him (they already have all the info to make the tranny work for you, adapters, throw out bearing, etc......

Some of you might have seen my 7 on Ebay (it was the 100% carbon fiber rx-7).... Anyway the tranny is very wide, and you will need to cut the transmision tunel to get it in there, you will also need to move your drivers seat 1.5 inchs the the left side.

A couple of years ago I had a 3rotor in a FD and I had the Pettit subframe, having the motor so far forward is a bad thing, your steering geomitry goes to ****, also you now have more weight on the front tires. So I moved the motor back 7.5 inches and put the rack back in the stock location (car was great after that)...

If you are going to do the 20b, do it right... Buy the Jerico 5spd and move the motor back to run the stock rack. I am working on my new FD right now it will have 3 rotor periphrial port N/A that will make 480 horsepower and 330 torque (I am having CLR build the motor)... I will be moving the motor back to run the stock rack, not sure on tranny (since it is non-turbo I might run the stock tranny and make an adapter to move the shifter forward, or just put another Jerico 5spd in).....

Anyway I hope that this info, helps (since I have already done what you are trying to do and gone through it, it should help).....