Question for stick shift racers

Garbageman

Garbageman

 
Supporting Member 1
I am switching out my M22 for a Jerico 4spd this winter and have a couple of questions.

First some background. My car weighs approx. 3900lb with me in it. Second my rear ratio is 4.10, which puts me through the traps at 6100 rpm where I want it. And third I am using a 9 x 26 slick designed for stick cars.

1. What first gear ratio would work well? Jerico recommended a 3.08 but my engine guy says 3.20 range. What are your thoughts?

2. I have been using a RAM 6 paddle metallic disc with a 2800lb long pressure plate. I plan on using the same but stepping down to a lighter pressure plate. I am not a high hp car, 400+, so I feel this combo will continue to work well. Soft lok and dual stage clutches are more expensive and probably over kill for me. I'm I right.

3. Input shaft on the M22 is if I'm not mistaken a 10 spline. Jerico will put a 10 or 26 spline. I think, like axles, the more splines the better so I'm thinking 26 spline input shaft.

I just want to hear from anyone racing a stick and get your thoughts.

Thanks
Paul
 
H

HIVOLTAGE

Well Known Member
I competitively drag race but with an automatic trans. I trap at 126mph and cross the line at about 5600rpm's and run 10.9 et's. I haven't ran with the n2o yet which should net me some lower numbers. Oops, sorry - I forgot where I was for a moment. I'm not on my f**d Lightning website right now am I?:dunno :p :D

Just being a smartazz, I'll return you to your normally scheduled program already in progress.:rolleyes:
 
CDNpontiac409guy

CDNpontiac409guy

Banned
Congratulations, Paul !... you're graduating to having a first gear;) :deal !
I hate the close ratio thing.

If I'm not mistaken, the "M22", although being simply the GM option code for the HD 4 speed, is customarilly identified as the late model HD close ratio aluminum case Muncie, that was available in the big horse, Chevelles, Camaros, Novas, Corvettes, and extremely rare big cars... 69-72 ? ( probably 442, GSX, ect, as well ).
A rare bird indeed. This is the one that we think of, which has the large output, and 26 spline input.

Anyhow, the 26 spline input is stronger, simply because the splines are a shallower cut into the diameter of the shaft, thereby leaving a larger "minimum" diameter of that shaft.

With your 4.10's, I'd be inclined to agree with your engine guy, and be near 3.20. However, this gear will certainly get that torque multiplication to your driveshaft, and crown and pinion. So, you better make sure you have these items ready for the fight:brow .

The 3.08, to myself personally, would be my selection. I made the mistake when I ordered my Jerico for my Stocker, by selecting a 2.83 first gear. Yes, it IS easier on driveline parts. Yes, it DOES provide a very even spread between all shifts, which I like. But if I ever get this thing to hook, I'm concerned that I'll find that it's not enough... and I have a 5.13 rear gear.

Aluminum... aluminum flywheel. I think that's a given, especially with the low first gear transmission. Easier on driveline parts, quicker engine RPM gain, particularilly in 1st and 2nd gear. The result will be 20-25 pounds of rotating mass off odf the front end of the car. Can only help.

A soft hitting clutch, will be easier on parts too, as well as providing a bit of a "cushion" from pulling the enginge down too much on launch.

All big talk:yawn: .
Hopefully, some of the guys who have actually made their car work, will post with their recommendations:coffee:
 
Garbageman

Garbageman

 
Supporting Member 1
Aubrey, thanks for the input. I respect your knowledge.

I've done a lot of research and calculations on other websites and a 3.20 would be ideal for my ratios but I haven't built the car to take that hard of a hit yet. I have replaced the 2 piece drive line with a single piece and that connects to a 9in with the big bearings and 31 spline axles.

Getting rid of the 2.20 first gear and moving to a 3.08 or 3.? will get rid of my bog and launch the car like a real racecar.

I am going to stay with my current steel flywheel for now, it's only got one season on it. If I do get into this project and find it is toast I will change it. Do you really feel an aluminum flywheel works better on a 409? I have always been afraid it would rev too fast and not stay together. Maybe I am a little over cautious.

Thanks again for your advice.

Paul
 
CDNpontiac409guy

CDNpontiac409guy

Banned
Garbageman said:
Do you really feel an aluminum flywheel works better on a 409? I have always been afraid it would rev too fast and not stay together. Maybe I am a little over cautious.
Paul
Click to expand...

Thanks Paul...

Rev too fast ?
nah....
Just be prepared to be REAL BUSY:deal :deal
Besides, it's nothing that a 6200 RPM chip in your rev limiter can't look after.

Sounds like the driveline will be fine.

Yeah, I'm THAT convinced of an aluminum flywheel. As long as there's a good gear multiplication in 1st, for both racing, AND just driving around, I think a heavy steel flywheel is just a collosal waste of energy:dunno

Hey, if your car daylights the front tires, please let me in on the secret:bow :p
 
Garbageman

Garbageman

 
Supporting Member 1
Aubrey, you got a deal:D If I daylight the front I'm going to be jumping for joy...as I run back to the motorhome to change my shorts.:roll

I'll make the change to aluminum when I can. I do use a chip already.

Thanks

Paul

Hey, when are you coming south for a visit? DQ needs some proding to get his act together.

Paul
 
Quickshift409

Quickshift409

Well Known Member
Supporting Member 11
Paul, I have a M-20 Muncie with 2:56 first and use a Hoosier 27" tire. It makes 6300 at the traps.
 
jim_ss409

jim_ss409

Well Known Member
Supporting Member 5
I have the same rear gearing and tires on my convertible, 4.10 gears and 26" X 9" slicks. I went from a close ratio Super T-10 with a 2.45 first gear to a Tremec 5 speed with a 2.8? first gear and it was a big improvement. So my guess is you should see a HUGE improvement with either the 3.08 or the 3.20's. The first to second shift is going to come up real quick.:beerbang
 
CDNpontiac409guy

CDNpontiac409guy

Banned
Paul... I was just thinking ( actually, it took a lot to lead up to what one could call "thinking" )...
The Jerico ?
Why a Jerico ?
A new Super T10, with a 2.88 1st gear, is available for about $1500.
( oh, the Jerico requires modification to the transmission tunnel on the floor, as well as a lower mounting pad )
 
Garbageman

Garbageman

 
Supporting Member 1
I had thought about a Richmond Super T-10 but I didn't think the first gear was low enough, though I have been known to be wrong. I didn't know the tunnel needed modifying for the Jerico to fit. Why does it need modifying and what do you need to do?
I am looking at the DR4 tranny.
Thank Aubrey

Paul
 
CDNpontiac409guy

CDNpontiac409guy

Banned
They're square and bulky. The top outer edges of the main case, will contact the underside of the trans tunnel at some point. I had to cut a slot in mine, and add a strip of sheet metal about 1-2" wide, "insert" it, and weld it... effectively making the tunnel wider ( shifter linkage really gets in the wat as well... particularilly 63 and earlier cars... yes, the tunnel is different on a 64 ! ).


http://www.bruneauperformance.ca/mybelairjericot10.jpg
 
SSpev

SSpev

Well Known Member
Supporting Member 3
watch out for the torque ratings of a ST10. each lower gear ratio has a lower torque.
http://www.richmondgear.com/cat/supert10.html

My brother split the case of a ST10 with a 2.43 1st gear (strongest) in his 65 Skylark 455. run 12.2s luanch at 5000. Had a paddle disk and 3.73. I t might have lived if it had the right clutch/disk and a lower launch.

I have a 2.43 ST10 I am planning to try in a Biscayne behind a 396 +60 (409:D )
lower launch, 4.10, less torque.
 
DIV1RACER-2

DIV1RACER-2

Well Known Member
Supporting Member 12
Jerico

Paul what i am gonna describe here is my personal experiances / Not written in stone !!


[ 1 ] If you don't drive the car on the highway at all the Jerico is definately the way to go, the T-10 might have been a good way to go when the 9310 gear sets were avalible . We used to move 1st gear ahead .125 and use steel rear supports to make them live , but there we no other options. Seldom in life are things better than you expect , a Jerico is one of a very few .

[ 2 ] As far as gear ratios go there is a way to have your cake & eat it too, depending on which 1st gear counts you are advised by Jerico to use 33/15 or 34/16 , with a head set change [ the input gear & frt gear on cluster ] the ratio can be changed from 3.08 to either 3.17 or 3.19 . I'm not sure of the cost now but for $250.00 , give or take you can change to a deeper 1st gear .

[ 3 ] The 26 spline input is what you want .


[ 4 ] I would change the pressure plate to a Ram # 435 , it is a long style 1200 -1800 lb , more than enough pressure w/o having slippage problems to deal with , the clutch disc part# is 6130 . It is a 6 paddle metallic , wears like iron & is very dependable & repeatable [ doesn't change as it gets hot ] ......This is the exact setup i run in both cars , not expensive & you can send back to Ram and have it rebuilt . As a matter of fact send yours to them & have it updated !!

[ 5 ] I have to disagree w/ Aubrey as far as floor modification for trans clearance, the trans is a little tight but clears everything on my car , you do have to remove a section from floor to clear the lenght of the 3-4 shift rod. You also must notch crossmember and drop rear of trans about 3/4 -1 inch . The mount pad is that much lower .

[ 6 ] Use the steel flywheel till you outgrow it . w/ small cubes & a heavy car it will help in the first few feet , it does hurt down track some / probably a trade off !


I have gone 1.45 60' -- 1.47 - 1.48 regularly w/ the biscayne & 1.35 best in the camaro w/ this set up . I have broken the Jerico 1 time w/ a 1st gear tooth count that Jerry H. said was weak !!!!!


JMHO :dunno :dunno
 
Garbageman

Garbageman

 
Supporting Member 1
Thanks Denny.

That's a lot of good first hand information and experience. I looked at the ST-10 from Richmond but as SSpev said their torque ratings aren't very reassuring. I will order the Jerico tomarrow and talk about gear sets, tooth count. And, as Aubrey said, I need to modify the tunnel I will do that.

There aren't many racers here in Oregon running stick shifts so it's hard to get experienced opinions. The one guy I do talk with on occasion is Johnny "Jerico". He has a straight axle '57 Chev, gasser stance, with a 327 and Jerico 4spd. He runs 10.20s easy. It's a beautiful car. He is sold on the Jerico for us more budget minded racers.

Thanks again

PS I still haven't fixed the fricken trunk you helped me with in Kansas City. Oh well.

Paul
 
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