An info post regarding my ZF6 conversion
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,146
Likes: 2
From: Albuquerque NM
An info post regarding my ZF6 conversion
The impetus for this is the search for a non-mcleod twin disk setup...if you wanna do it right-do it your self. I was looking at stuffing other companies twin setups into the bell housing with a howe hyd throwout bearing.
I have a L98ish stroker crank that sticks out from the block 18mm
the bellhousing (p/n magnesium 10126448) surface to surface is 153.8mm. This measurement includes the two 0.032" "isolation" shims on either end of the bell housing.
The transmission (blue tager) juts into the bellhousing 13mm not including the front bolts. I measured my diameter to be 33.4mm (1.31")
thus the clearance from crank surface to transmission is 153mm - 18mm - 13mm = 122.8mm (4.83").
I talked to the ram clutch dude in S. Carolina. Their twins range from 3.1" to 3.16" crank to clutch fingers and require 0.450" to accuate. Thus the Hyd TB needs to be 1.675" - 1.735".
... doable except that the ram twins are 168 tooth vice the vette 153 tooth and that you need some sort of bearing race between the clutch fingers and the bearing.
Thoughts, additions, haters?
I have a L98ish stroker crank that sticks out from the block 18mm
the bellhousing (p/n magnesium 10126448) surface to surface is 153.8mm. This measurement includes the two 0.032" "isolation" shims on either end of the bell housing.
The transmission (blue tager) juts into the bellhousing 13mm not including the front bolts. I measured my diameter to be 33.4mm (1.31")
thus the clearance from crank surface to transmission is 153mm - 18mm - 13mm = 122.8mm (4.83").
I talked to the ram clutch dude in S. Carolina. Their twins range from 3.1" to 3.16" crank to clutch fingers and require 0.450" to accuate. Thus the Hyd TB needs to be 1.675" - 1.735".
... doable except that the ram twins are 168 tooth vice the vette 153 tooth and that you need some sort of bearing race between the clutch fingers and the bearing.
Thoughts, additions, haters?
Last edited by ZD1; Apr 22, 2008 at 02:44 AM.
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Figure out what the necessary clearance requirement and then buy a spacer to put in between the BH and the block@ $60 or make your own like I did, then buy an extended Pilot Bearing for @ $20.
I have a Howe with a standard Ram PP, and spacers between my BH/Block.
I have a Howe with a standard Ram PP, and spacers between my BH/Block.
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,146
Likes: 2
From: Albuquerque NM
What clutch are you running? My dilema is to fit the biggest clutch (twin) possible. Otherwise, I'd just go with the ram c4 conversion.
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Buy the Twin package that you want, then bolt the thin FW on and the clutch package,,, then bolt the Bell housing on,,, measure from the BH mount face to the clutch fingers....
Now take the HOWE brand TOB and slide it onto the tranny and measure from the TOB collapsed face to the tranny mount face....
Take the difference and make sure that you have the necessary TOB disengagement travel,,, plus @ .250" for clearance......
What ever your stack up totals, is what you need and what you lack can be added by using a spacer between the BH and the Block,,,,
Here is a link that describes this as well, but he is using a McLeod #1345 TOB. Personally, I would use the McLeod TOB if you can swing the cost.
Also, because of the TWIN package, you will need to consider your Master cylinder bore as well.
http://forums.corvetteforum.com/show....php?t=1740664
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
Not that there isn't 40 thousand threads on the topic, but try these for starters:
http://members.cisdi.com/~anesthes/zf6/
http://members.cisdi.com/~anesthes/projects/stick-swap/
I don't know if your car is auto or 4+3, but either way those to links have
it covered.
(and rather than posting BS, or posting what a mechanic in some shop said he did - everything in those links have been done and covered by me, and in most cases been apart and together numerous times and ways before I finalize the perfect solution).
-- Joe
http://members.cisdi.com/~anesthes/zf6/
http://members.cisdi.com/~anesthes/projects/stick-swap/
I don't know if your car is auto or 4+3, but either way those to links have
it covered.
(and rather than posting BS, or posting what a mechanic in some shop said he did - everything in those links have been done and covered by me, and in most cases been apart and together numerous times and ways before I finalize the perfect solution).
-- Joe
Burning Brakes
Joined: Feb 2007
Posts: 865
Likes: 20
From: warner robins Georgia
Not that there isn't 40 thousand threads on the topic, but try these for starters:
http://members.cisdi.com/~anesthes/zf6/
http://members.cisdi.com/~anesthes/projects/stick-swap/
I don't know if your car is auto or 4+3, but either way those to links have
it covered.
(and rather than posting BS, or posting what a mechanic in some shop said he did - everything in those links have been done and covered by me, and in most cases been apart and together numerous times and ways before I finalize the perfect solution).
-- Joe
http://members.cisdi.com/~anesthes/zf6/
http://members.cisdi.com/~anesthes/projects/stick-swap/
I don't know if your car is auto or 4+3, but either way those to links have
it covered.
(and rather than posting BS, or posting what a mechanic in some shop said he did - everything in those links have been done and covered by me, and in most cases been apart and together numerous times and ways before I finalize the perfect solution).
-- Joe
cool thanks for the info.
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,146
Likes: 2
From: Albuquerque NM
actually i have a very nice/$$ zf-1 AL single mass flywheel
sigh!!!!!
sigh!!!!!
Mine is the Ram-410 / PP, but the only thing you need to be concerned about is having enough clearance for the TOB, I am assuming that you are NOT using a ZF flywheel , correct? You will need to use a thin Billet FW for your model year.
Buy the Twin package that you want, then bolt the thin FW on and the clutch package,,, then bolt the Bell housing on,,, measure from the BH mount face to the clutch fingers....
Now take the HOWE brand TOB and slide it onto the tranny and measure from the TOB collapsed face to the tranny mount face....
Take the difference and make sure that you have the necessary TOB disengagement travel,,, plus @ .250" for clearance......
What ever your stack up totals, is what you need and what you lack can be added by using a spacer between the BH and the Block,,,,
Here is a link that describes this as well, but he is using a McLeod #1345 TOB. Personally, I would use the McLeod TOB if you can swing the cost.
Also, because of the TWIN package, you will need to consider your Master cylinder bore as well.
http://forums.corvetteforum.com/show....php?t=1740664
Buy the Twin package that you want, then bolt the thin FW on and the clutch package,,, then bolt the Bell housing on,,, measure from the BH mount face to the clutch fingers....
Now take the HOWE brand TOB and slide it onto the tranny and measure from the TOB collapsed face to the tranny mount face....
Take the difference and make sure that you have the necessary TOB disengagement travel,,, plus @ .250" for clearance......
What ever your stack up totals, is what you need and what you lack can be added by using a spacer between the BH and the Block,,,,
Here is a link that describes this as well, but he is using a McLeod #1345 TOB. Personally, I would use the McLeod TOB if you can swing the cost.
Also, because of the TWIN package, you will need to consider your Master cylinder bore as well.
http://forums.corvetteforum.com/show....php?t=1740664
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I have a 16lbs steel singlemass 4+3 flywheel on my ZF6.. On start up, and shut down it sounds like rocks in a clothes dryer. Not too terrible at idle. At first I thought something was in my BH bouncing around.. I imagine it would have came through the floor by now if that we're true. 
-- Joe
-- Joe