ZF conversion, need help!
Thread Starter
Instructor
Joined: Dec 2005
Posts: 188
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From: Riverside CA
ZF conversion, need help!
Hi All:
I have an 89 Convertable, with a S.C. 383
I am in the middle of changing my 700R4 to a ZF 6 Speed.
I bought all the peices from a wrecking yard.
What am I going to need for a flywheel? (need a 400 type)
What will I need for a clutch? (Needs to support 500/500 RW)
Anybody recomend a scater shield bell housing as opposed to the stock aluminum? These L98 Motors realy don't turn many RPM. I usualy run under 6,000.
Thanks for the help.
Chad Tombyll
I have an 89 Convertable, with a S.C. 383
I am in the middle of changing my 700R4 to a ZF 6 Speed.
I bought all the peices from a wrecking yard.
What am I going to need for a flywheel? (need a 400 type)
What will I need for a clutch? (Needs to support 500/500 RW)
Anybody recomend a scater shield bell housing as opposed to the stock aluminum? These L98 Motors realy don't turn many RPM. I usualy run under 6,000.
Thanks for the help.
Chad Tombyll
Burning Brakes
Joined: Sep 2001
Posts: 1,013
Likes: 9
Originally Posted by BLWN BUX
Looking at Aluminum Flywheels, any Input?
Thanks,
Chad
Thanks,
Chad
Later tonight I plan to list the flywheel you need in the C4 Classifieds. It is a new custom Fidanza aluminum flywheel made specifically for mating a ZF6 transmission to an 2 piece rear main seal small block. It is presently neutrally balanced, but has a machined attachment point for adding a balance weight to match 400 externally balanced cranks.
I also have a new Spec stage 3+ clutch rated for 800 ft lb that I plan to sell.
Last edited by Mr6spd; Nov 26, 2006 at 03:04 PM.
Le Mans Master
Joined: Sep 2000
Posts: 6,303
Likes: 714
From: Bartlett IL
Originally Posted by BLWN BUX
Looking at Aluminum Flywheels, any Input?
Thanks,
Chad
Thanks,
Chad
Thread Starter
Instructor
Joined: Dec 2005
Posts: 188
Likes: 0
From: Riverside CA
Thanks ,
Actualy I decided to go with a "RAM" conversion
It comes with a new slave cylinder conversion that will turn the PPlate into a pusher type. I am to understand that the puller type has limitation in the PP #'s . I am now getting a 2800#er with a dual friction disc and aluminum F.W. Shuold be good to 600RW
Thanks All
Actualy I decided to go with a "RAM" conversion
It comes with a new slave cylinder conversion that will turn the PPlate into a pusher type. I am to understand that the puller type has limitation in the PP #'s . I am now getting a 2800#er with a dual friction disc and aluminum F.W. Shuold be good to 600RW
Thanks All
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by Mr6spd
Later tonight I plan to list the flywheel you need in the C4 Classifieds. It is a new custom Fidanza aluminum flywheel made specifically for mating a ZF6 transmission to an 2 piece rear main seal small block.
Thanks ,
Actualy I decided to go with a "RAM" conversion
It comes with a new slave cylinder conversion that will turn the PPlate into a pusher type. I am to understand that the puller type has limitation in the PP #'s . I am now getting a 2800#er with a dual friction disc and aluminum F.W. Shuold be good to 600RW
Thanks All
Actualy I decided to go with a "RAM" conversion
It comes with a new slave cylinder conversion that will turn the PPlate into a pusher type. I am to understand that the puller type has limitation in the PP #'s . I am now getting a 2800#er with a dual friction disc and aluminum F.W. Shuold be good to 600RW
Thanks All
Last edited by CentralCoaster; Nov 27, 2006 at 09:44 PM.
Burning Brakes
Joined: Sep 2001
Posts: 1,013
Likes: 9
[QUOTE=CentralCoaster]There is no need for a custom flywheel to put a ZF on a 2-pc seal block. Any 85-86 Corvette flywheel will work. I'm using one right now. The 84 flywheel might also work. For the same reason, I also expect that an 87-88 flywheel would work for a ZF conversion on any 1-pc seal block.
QUOTE]
I pulled a 4+3 out of an 1985 vette ... Trying to use the stock 85 flywheel, There is not enough room for a sprung hub disk to clear the crankshaft bolts. The recess is simply not deep enough.
I had read before on ther Forum that you could use the stock 85-86 flywheel, So that was my plan. But there was no way it would actually work.
Are you using a non-srung hub disk with the stock 85-86 single mass flywheel? Or did you find a special sprung hub disk that is not as thick as the normal? The SPEC disk that I have sure won't fit with that flywheel.
QUOTE]
I pulled a 4+3 out of an 1985 vette ... Trying to use the stock 85 flywheel, There is not enough room for a sprung hub disk to clear the crankshaft bolts. The recess is simply not deep enough.
I had read before on ther Forum that you could use the stock 85-86 flywheel, So that was my plan. But there was no way it would actually work.
Are you using a non-srung hub disk with the stock 85-86 single mass flywheel? Or did you find a special sprung hub disk that is not as thick as the normal? The SPEC disk that I have sure won't fit with that flywheel.
Last edited by Mr6spd; Nov 28, 2006 at 12:26 AM.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I'm using the 85 flywheel with the ZF6 (springless) clutch and pressureplate.
I'm not sure what clutches work. I know the Camaro clutch has a smaller hub. Clearing the crankshaft bolts isn't the concern (the stock clutch's large sprung hub obviously clears them), it's whether or not the hub clears the pressure plate.
I'm not familiar with the 1-pc crank setups. If it helps, I have a list of the parts interchangability between years. I also measured everything on mine for future reference. I wonder if that RAM setup or new Mcleod setup will work on 2-pc cranks. The only reason it wouldn't is if the crank extends futher back.
I'm not sure what clutches work. I know the Camaro clutch has a smaller hub. Clearing the crankshaft bolts isn't the concern (the stock clutch's large sprung hub obviously clears them), it's whether or not the hub clears the pressure plate.
I'm not familiar with the 1-pc crank setups. If it helps, I have a list of the parts interchangability between years. I also measured everything on mine for future reference. I wonder if that RAM setup or new Mcleod setup will work on 2-pc cranks. The only reason it wouldn't is if the crank extends futher back.
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Burning Brakes
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
Originally Posted by CentralCoaster
There is no need for a custom flywheel to put a ZF on a 2-pc seal block. Any 85-86 Corvette flywheel will work.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by JLeatherman
He said it's a 383. Therefore it needs an externally balanced flywheel which means he can't use the stock flywheel. I just went through this with my engine and ended up going with a Hays.
I presume the original poster has a 1-pc seal crank, so none of our last few posts apply, I was just getting off topic. In fact, I'm not sure what the original poster has, he never said.
Burning Brakes
Joined: Sep 2001
Posts: 1,013
Likes: 9
Originally Posted by CentralCoaster
I'm using the 85 flywheel with the ZF6 (springless) clutch and pressureplate.
I'm not sure what clutches work. I know the Camaro clutch has a smaller hub. Clearing the crankshaft bolts isn't the concern (the stock clutch's large sprung hub obviously clears them), it's whether or not the hub clears the pressure plate.
I'm not familiar with the 1-pc crank setups. If it helps, I have a list of the parts interchangability between years. I also measured everything on mine for future reference. I wonder if that RAM setup or new Mcleod setup will work on 2-pc cranks. The only reason it wouldn't is if the crank extends futher back.
I'm not sure what clutches work. I know the Camaro clutch has a smaller hub. Clearing the crankshaft bolts isn't the concern (the stock clutch's large sprung hub obviously clears them), it's whether or not the hub clears the pressure plate.
I'm not familiar with the 1-pc crank setups. If it helps, I have a list of the parts interchangability between years. I also measured everything on mine for future reference. I wonder if that RAM setup or new Mcleod setup will work on 2-pc cranks. The only reason it wouldn't is if the crank extends futher back.
I know first hand from my friend's aggravating experience, that using a regular ZF non sprung disk with a single mass flywheel is a very bad thing. Others on the forum have made the same mistake. It is pretty much universally recommended on the forum, and by the clutch manufacturers, that you use a sprung hub disk with a single mass flywheel.
So to clear it up for all who are planing to use a 2 piece rear main seal engine: No, you can't use a stock 85-86 single mass flywheel, if you want to use a correct sprung hub disk.
Last edited by Mr6spd; Nov 28, 2006 at 11:12 AM.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I've seen a lot of feedback from those with sprung hub disks, and they seemed to have very little effect on the trans rattle. I think I read somewhere (ZFdoc or G Killebrew?) that said the sprung hub clutch wasn't capable of silencing the ZF, and that's why they had to design a new flywheel. The dual mass flywheel spring is very different than a sprung clutch.
On the other hand, there's a huge difference between single mass aluminum flywheels and stock single mass grey cast iron flywheels, regarding the trans rattle. The iron fw is much heavier and dampens better. Which did your friend use?
My car has noticeable rattle at warm idle in neutral, particularly when parked next to a wall, but the transmission noise at all other times is insignificant. I'll confess that I haven't ridden in any ZFs with a sprung clutch or dual mass alum flywheel.
On the other hand, there's a huge difference between single mass aluminum flywheels and stock single mass grey cast iron flywheels, regarding the trans rattle. The iron fw is much heavier and dampens better. Which did your friend use?
My car has noticeable rattle at warm idle in neutral, particularly when parked next to a wall, but the transmission noise at all other times is insignificant. I'll confess that I haven't ridden in any ZFs with a sprung clutch or dual mass alum flywheel.
Burning Brakes
Joined: Sep 2001
Posts: 1,013
Likes: 9
My friend used a 13lb aluminum flywheel ... but the 85-86 iron flywheel is lightweight at only 15 lb ... not a big difference.
The clutch disk configuration results from my friend's '91: 1) Solid disk, 2) Mcleod disk with 1/2 over molded springs (semi-rigid), 3) sprung disk with springs only.
Observations:
-Idle Gear noise was not much differnent between the three clutch disk types.
-Noise and vibration under load at low rpms (under 2500) in 5th and 6th gear: Dramatic differences between the clutch disks. Solid disk was by far the worst, Mcleod was better but still not great, spring only disk was much better.
The clutch disk configuration results from my friend's '91: 1) Solid disk, 2) Mcleod disk with 1/2 over molded springs (semi-rigid), 3) sprung disk with springs only.
Observations:
-Idle Gear noise was not much differnent between the three clutch disk types.
-Noise and vibration under load at low rpms (under 2500) in 5th and 6th gear: Dramatic differences between the clutch disks. Solid disk was by far the worst, Mcleod was better but still not great, spring only disk was much better.
Le Mans Master
Joined: Sep 2000
Posts: 6,303
Likes: 714
From: Bartlett IL
There's a big difference in mass between the AL and Iron FW. The AL spins up so much more readily. I was originally going to use the 84 FW but found that it required a "modded" ZR-1 clutch fork pivot. That's because the FW is thin and the fork needs the extra travel to engage the disk. Otherwise the clutch grabs right at the bottom. And I didn't want to do this all over again, so I took the plunge on an AL FW. Fidanza makes FWs specifically for both the 2 piece and 1 piece cranks retro-fitting the ZF trans.
Racer
Joined: May 2005
Posts: 360
Likes: 0
From: Canton GA
Originally Posted by Mr6spd
-Noise and vibration under load at low rpms (under 2500) in 5th and 6th gear: Dramatic differences between the clutch disks. Solid disk was by far the worst, Mcleod was better but still not great, spring only disk was much better.
Thats interesting because I do get ALOT and I mean ALOT of vibration and noise in 6th gear under 2000rpm.... now I know why.
But 5th isnt bad, and the rest of the gears are quiet.. I do get some trans rattle in N, but its not a big deal.
