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Discussion Starter · #1 ·
So who has trod this ground before me? I'm having "issues". Believe me, I've searched here, several other forums, and google. I've already gotten a pricey Quicktime LS- to Gen1 adapter bellhousing. Now, I find the nice Z06 LS7 flywheel I got with the transmission deal has to be changed to a regular old 2pc flywheel.

I'm ok with that, and according to a popular online partshouse tech I should be able to reuse my LS7 press/plate and disc. I'm not seeing it as so easy. Every Gen1 flywheel I see illustrated is completely flush across and does not have a spring recess that is clearly needed for the LS7 disc I have.

I don't mind ditching the whole LS7 clutch setup, but maybe you can see where this is going. Am I going to find when going to an old-style Gen1 press/plate setup that I can no longer use the LS- type pusher slave cyl., and that I have to go to either an LT- puller type slave or even a mech. Z-bar?

I want to see this go together, I'd just hope not to accumulate a bunch of parts and find it won't work anyway.
 

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You will basically want to treat this as , say , 71 chevelle, camaro, corvette when choosing components. 26 spline first showed up in 70 LS6 then became somewhat common 71 and up .

If you already have a starter in 153 teeth spacing and want to keep it then look at 10.5 or 10.95 clutches.

Be Careful with pilot bearing depth. If too far back, the LS7 bearing will help, if too far in you might need some creative bushing work.

Once you are mocked up you can determine finger height and whether or not you will need to spacer the LS throw out forward.

Should be a big deal.

Want to sell the LS bell housing?
Gerry
 

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Discussion Starter · #3 ·
Gawd Gerry. I hope you mean to say it should NOT be a big deal. ;)

I've been searching several places for info. s-10 and LS1Tech forums show guys who have done this, but they all seem to be using mech. linkages.

All the pics I see show 2pc. flywheels are flush with no spring pack recess. So, even though an LS- clutch and 168T 2pc. flywheel have the same 12 5/8" boltring I've pretty much confirmed it is not possible to bolt to two together.

I just got off the phone with the McLeod tech (pretty straight fella) and he mentioned the Gen1 crank-to-block offset is .4" further back than a Gen3. (Gen1 = .740, Gen3 = .340). I don't have the parts here for mockup so I'm concerned I'll run out of room to use a hyd. T.O. bearing.

If finger hts. are variable both ways then that may not be as big a deal as I'm fretting. I got a used 168T 2pc. flywheel on the way so that's a start.

Oh yah, about the b/h. Gerry you're the first to ask so ok. I can poke around looking for a price or you can PM me an offer. ;)
 

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Sorry , SHOULDN'T

If it helps, I have a 2 piece back end sitting here I can measure for you.
I should have enough bits around here to dummy up a clutch and flywheel .

And the LS7 but the flywheel is on and it is on the stand for a week or two more.
My bell housing is in between the LT and LS for depth and I am really hoping to use it (after welding the oil pan bosses on, but want to have an LS housing on hand if my plan goes awry.

Diaphram fingers are set in stone.
If guy was a little too tight, a piece sheet can be made into a block plate.
Or as I said the other direction, a throw out spacer
 

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Discussion Starter · #6 ·
......
Be Careful with pilot bearing depth. If too far back, the LS7 bearing will help, if too far in you might need some creative bushing work.

Once you are mocked up you can determine finger height and whether or not you will need to spacer the LS throw out forward.
........
Gerry
I already got a 14061685 ready, but your comment prompted more search. I'll be prepared in case the Quicktime converter b/h is not perfect.

http://www.ls1tech.com/forums/conve...-gm-extended-pilot-busing-2.html#post14045261



Pardon the cross-foruming, I'm just documenting this for any future search.
 

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Sorry to take so long getting back.
I mocked a two piece crank, flywheel , used disc, new McLeod diaphragm pressure plate together.
From the back of the block to the clutch fingers I get 3.83 inches.
Hope this helps you. Anything else I could check ?
Gerry
 

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Discussion Starter · #8 · (Edited)
Thanks. Funny, that happens to be very close to the ht. of just the Z06 flywheel, clutch and p/p I have. Then there's the crank-to-block offset to add to that.

The flywheel I have coming will eliminate one variable, and then I may have a question or two thanks.

You mentioned you need a LS- bellhousing. LMK And look at my parts and tell me if those 7/16" raised bosses are normal for all LS- flywheels, or is it just a Z06 thing? Other pics I've seen of LS- flywheels show just a flat face and depression for the spring hub.
 

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Unfortunately, my LS knowledge is extremely limited.
The only LS stuff I have on hand is the clutch assembly that came bolted to my LS7.

I do know there are many variants based on reading about fitting dual discs to LS engines but I have no idea what the thicknesses are.

http://www.lingenfelter.com/mm5/mer...de=LPE&Product_Code=L360031410&Category_Code=

Caddys with their dual mass flywheels also had unique distances.

Have you got your aftermarket bell housing in hand?
If so maybe plunk it on and measure from block mating surface back to the throwout.

I have interest in your stock LS bell housing in case my plan to reuse my Weir doesn't work.
Haven't contacted you yet.

Gerry
 

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Discussion Starter · #10 ·
I had posted a new thread
http://www.impalassforum.com/vBulletin/showthread.php?t=269918
hoping not to drag up this old one, but maybe I'm doing better to just stick with this.

So an update:

I mocked a two piece crank, flywheel , used disc, new McLeod diaphragm pressure plate together.
From the back of the block to the clutch fingers I get 3.83 inches.
Hope this helps you.
Gerry
With all the parts in I did the same mockup with my two piece crank (but remember it's on a one piece motor), oem steel 1 1/2" flywheel, new Sachs disc and diaphragm pressure plate together. For mine the back of the block to the clutch fingers is 4.125 inches.

I can't figure why/where the extra .29 is coming from compared to Gerry's stackup, which incidentally would be ideal for me.


.... I don't have the parts here for mockup so I'm concerned I'll run out of room to use a hyd. T.O. bearing.
It turns out my fear was real. The RhinoPac T.O. bearing I got is 2 1/4" compressed to tranny face. The diaphragm finger to bellhousing is 2 1/8". That's negative clearance and instant bind. There must be something about a 2-pc rear main seal on a one piece motor that throws the clearances off.

I would like another solution other than having to get a new (and pricey) T.O. bearing if they make slimmer ones. And Prestolite (bought QuickTime) has a 1/4" tranny spacer, but right now my input shaft dimension to pilot bushing is exactly right-on and I'd prefer not to mess with moving the tranny back.

Just wondering if anyone has gone through this too.
 

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If I had to guess , I would be thinking it's probably in the pressure plate. There seems to be no real standard for finger height with these clutch people.
You're about .125 pre loaded now and looking for .125 clearance.
I agree with this.
How thick is your clutch disc?
I can't do it right know but will try and get you flywheel face to finger assembled (possibly tomorrow).
One thing, are you posititve you have the throw out 100 % compressed ?
Gerry
 

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Don't know if it helps ,
Used Mcload disc .280 thick
Used Mcload 10.5 diaphram pressure plate.
Assembled , the fingers are 2.24 above the surface of the flywheel where the pp bolts down
Gerry
 

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I'm not sure of the exact measurement, but because of the thicker dual mass flywheel, the gen1 CTS-V slave is about 1 inch shorter than the LS7 slave. This pic shows the spacer that make up the difference. Perhaps that slave would work for you.


I'll be swapping my stock stuff for LS7 flywheel/clutch/pressure plate and slave in the next couple of weeks. I can measure the exact difference then.
 

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Discussion Starter · #14 ·
If I had to guess , I would be thinking it's probably in the pressure plate. There seems to be no real standard for finger height with these clutch people. I sure agree with you there. I made a similar comment in my other recent thread about most makers not listing the o.a. disc/PP stack ht. on different kits.

You're about .125 pre loaded now and looking for .125 clearance.
I agree with this.
How thick is your clutch disc? My new disc is ~.328.
I can't do it right know but will try and get you flywheel face to finger assembled (possibly tomorrow). Also, from that other thread - "My new Sachs 11" clutch and pressureplate I got is measured 2 7/8" (flywheel to fingers when bolted on). And, it appears Bryon on that other thread checked and has a McLeod setup with exactly the same stackup as that too.

One thing, are you posititve you have the throw out 100 % compressed ?
Gerry. Yah I probably pushed on that thing hard to the stop at least 30 times trying to get a smaller dimension. lol :(
Thanks for the dimension checks. I'm sure baffled where I'm losing clearance in my stackups compared to yours and others.
 

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What's up 96! I don't know if you realize that there is a shim under the slave cylinder. I had to install a Ram shim so it would disengage properly. I bought the transmission from D&D and it didn't come with a shim like the factory ones. Hope this helps.
 

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Discussion Starter · #16 ·
Yo bhop how's it going? Sadly yes I did know to look for the shim, so it's not part of the equation here.

It's going to be a few more months before I can work on the install again. My options then appear to be either the 1/4" tranny plate ("not so dood" as my grandson says), a slimmer adjustable TO bearing, or a slightly shallower PP/disc kit.

One thing is strange: I notice from the info for the flywheel I bought it specs 1.25" thick. I measured 1 1/2" (more than once). I'm reconfirming the measurement - one more time.

Dave M thanks for the lead on the TO bearing, but if I can't trace the problem to the flywheel I'll likely go after a different clutch kit to get that valuable 1/4" additional clearance.
 

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My push clutch is about the same dimensions as the one 95wagin posted. My clutch application is a late 70's Buick lemans,skylark with the pontiac 400 motor. Also my flywheel was thicker as well. one piece steel mcleod. I have been running a 3/8 spacer I cut for years without issue. just figured is put a little more info in print.
 
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