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-   -   Jerico 4-speed (https://www.rx7club.com/race-car-tech-103/jerico-4-speed-1013128/)

abeomid 09-27-12 04:39 PM

Jerico 4-speed
 
I have a lead on a nice Jerico 4-speed for my race car. How is everyone's experience with it (the guys that use it on race track - road racing)?

BigAl... 09-27-12 06:51 PM


Originally Posted by abeomid (Post 11236971)
I have a lead on a nice Jerico 4-speed for my race car. How is everyone's experience with it (the guys that use it on race track - road racing)?


I've used the Jerico in the past, it is one of the strongest tranny's around. any idea what ratios are in it? (very important!!!) If the ratio's aren't correct for your application you can easily spend as much as the cost of the tranny getting the correct ratios from Jerico. If you're lucky enough to get the right ratios that tranny will survive anything you can throw at it.

BigAl...

SCCAITS 09-27-12 09:32 PM

I have a Jerico 4spd and it's one of the better decisions I have made but that's also going to depend on your ratios.

abeomid 09-28-12 12:13 AM

2.56, 1.92, 1.42, 1
Car will have a 3.55 rear end.

SCCAITS 09-28-12 08:07 AM

***

abeomid 09-28-12 09:04 AM

Well with my 23.5 tire and 7000rpm I am looking at 54mph, 72, 97, 128. I will need a much taller final ratio. Even with a 3.08, I am getting 159mph. This 1:1 top gear sucks! I like to get 175-185mph top out of it.

BigAl... 09-28-12 09:30 AM


Originally Posted by abeomid (Post 11237646)
Well with my 23.5 tire and 7000rpm I am looking at 54mph, 72, 97, 128. I will need a much taller final ratio. Even with a 3.08, I am getting 159mph. This 1:1 top gear sucks! I like to get 175-185mph top out of it.



those ratios look very friendly, how much is the guy asking for the tranny? keep in mind with the taller r&p your rpm will be lower in the slow corners. do you know what your slowest corner mph is at the track you visit the most? you don't want to be killed in that corner and have to spend the rest of the lap trying to catch up. you do have an advantage over the setup I used to run and that is TORQUE.

abeomid 09-28-12 10:56 AM

$2,000. Fresh rebuilt and it was from a Roush Performance car. I think a 2.9x final ratio would do the trick. Now that would most likely require that I go into first gear in Portland track, although I might be able to pull out if the engine has good torque around 3500-4000rpm. Most likely over 200ft.lbs!

Yes TORQUE definitely helps! Running 13B's on the track for years, keep having to remind myself that!

abeomid 09-28-12 10:57 AM

By the way, what are you currently running in your car BigAl as far as the transmission goes? (From the previous pictures on your thread, looks like Jerico)

BigAl... 09-28-12 11:01 AM


Originally Posted by abeomid (Post 11237761)
$2,000. Fresh rebuilt and it was from a Roush Performance car. I think a 2.9x final ratio would do the trick. Now that would most likely require that I go into first gear in Portland track, although I might be able to pull out if the engine has good torque around 3500-4000rpm. Most likely over 200ft.lbs!

Yes TORQUE definitely helps! Running 13B's on the track for years, keep having to remind myself that!


thats a good price for a fresh Jerico, crunch your numbers (lowest mph, r&p, top end etc...) and if they work out you won't be disappointed with the Jerico. it will be one less thing to worry about.

BigAl...

SCCAITS 09-29-12 08:35 AM


Originally Posted by abeomid (Post 11237646)
Well with my 23.5 tire and 7000rpm I am looking at 54mph, 72, 97, 128. I will need a much taller final ratio. Even with a 3.08, I am getting 159mph. This 1:1 top gear sucks! I like to get 175-185mph top out of it.

Is this a RR car? I don't know what tracks you run but even the roval tracks where I am 140mph is about top speed. I've got a .72 spread from 1st to 4th and spend all my time at 65-140mph on a road course - 80/98/116/137mph, nice consistent RPM drop between gears and always in the peak power range. Seems to me you won't be using 1st at all but rather just 2-3 with an occasional 4th. Take it FWIW but that gearing doesn't look optimized for RR but that $2k price tag is very low. I just spent $1500 having mine refreshed and paid way more than $2k for it.

abeomid 09-29-12 08:38 PM

It is a road race car. The car is 600hp turbo engine, so little bit different than your E-prod. both Seattle and Portland have pretty long straights. I will do some more crunching with the gear ratios to see.

Thanks for the input guys! Keep it coming!

SEDUCE 10-28-12 04:59 AM

Hey guys just wondering if anyone an give me a hand I have just got a jerico 4spd for my fc and I need a cross member for it. Has anyone used a jerico in a fc and where did u get or did u make your cross member?

My ratios are 3.29-2.03-1.45, and 1:1 but I have the stock s4 diff ratio which I think is 4:11.

SCCAITS 10-28-12 09:49 AM


Originally Posted by SEDUCE (Post 11269233)
Has anyone used a jerico in a fc and where did u get or did u make your cross member?

I modified a stock manual tranny mount. Can't find any pics on my computer but if you send me a PM I'll try and stop by the shop and take some this week.

SEDUCE 10-28-12 12:39 PM

Thanks SCCAITS, pm sent
Anyone here use te DR4? As that's what I have it I got told it was clutchless box and found out after I brought it that it wasn't so wasn't happy.
So these are strong boxes ah?

CJarrett 11-02-12 06:02 PM

Were you guys able to fit it up with just an adapter plate? Up to the stock bellhousing?

abeomid 11-03-12 11:25 PM

Most adapter plates use the TII bell housing!


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