Eddie 70

iTrader: (3)

I am wanting to put an LS in my 70 vette. I am trying to gather info and parts as I go along to try and make this as painless as possible. I have a few questions. First one is, is the pilot bearing in the LS motors the same size as in the old small block chevy? Also, what about the flywheel? The reason I ask is because I now have a Keisler 5 speed in my vette and would like to be able to reuse that transmission as it only has around 5K miles on it or so.

Any help you can give would be greatly appreciated.

Novas Forever

Take a look in the Stickys for at least some of what you are looking for. I put a Muncie 4 speed behind my LS1 and it certainly works but there are some tricky items to consider, the pilot bushing/bearing being one of them. Your Keisler is probably like a Muncie dimension-wise. It would be easier for you since you can use a standard Chevrolet bellhousing. Beautiful car by the way.

Eddie 70

iTrader: (3)

My car had an M20 in it when it came from the factory. All I really had to do was make sure the bell housing was going to allow the input shaft center line and crankshaft center lines were in line.

Did you reuse the stock bell housing in your installation? I know Keisler makes some hybrid bell housing but I do not know if they have accommodations for the stock style clutch linkage.

I will check out the sticky for the pilot bearing stuff and post my findings here.

Eddie 70

iTrader: (3)

Looks like you had a special bearing made. Where did you have this done at, Local machine shop?

Novas Forever

I used the GM bearing and it worked OK but the extended bushing would be my choice now. Since a Chevy II has the clutch fork at the 5 o'clock position I couldn't use a stock regular bellhousing not the stcok Chevy II housing since it would only allow a small flywheel. I went with a Lakewood scattershield to use as an adapter, didn't need the protection. I had to modify the block plate because there are parts that stick out beyond the mating surface in the area between the block and flywheel. I would probably just leave the block plate off next time. It bolted right up minus 1 bolt that is not used. I have got to fabricate the clutch z-bar mounts, they mount on the block from the factory. It will all work it just takes some patience to figure it out.

Eddie 70

iTrader: (3)

Keisler responded to me that they make an extended bearing for the LS motor. That should help quite a bit. They also make a bellhousing that will adapt the LS to the Muncie, of course at a price.

I think I read that you just used the standard bellhousing and had to leave one bolt out. How is that working out now that you have had a chance to add a few miles to the car?

69blackwidow

iTrader: (1)

eddie70, i used an extented pilot bushing from day motorsports. i think it was like 10 dollars mike

Eddie 70

iTrader: (3)

Sweet deal. I will look into it and get me one on order since it seems I am going to need one.

Eddie 70

iTrader: (3)

Would you happen to have the part number anymore? I looked at their website and did not see what I was looking for.

G-Body

iTrader: (4)

The missing bolt should not be a problem as far as durability. There are a bunch of guys with 4th gen f-bodies that have stuck in th350 and th400 transes because they were sick of rebuilding 4l60e`s after blowing them up at the dragstrip, and I have not heard of anyone having problems with only using 5 bolts.

nitrovette

iTrader: (13)

Ive only got 5 bolts in mine eddie with my 700r4 and its fine,i beat on it pretty good too every chance i got.

Eddie 70

iTrader: (3)

Thanks for chiming in Patrick. Good to know I can get away with the stock bellhousing.

I believe I will just use what I have.Now if I can come up with a solution to my clutch linkage. I want to use the stock stuff if I can.

V8 Supra Builder

iTrader: (37)

I got some good pilot bearing/bushing information here when I installed the Tremec TKO600 behind my LM7 Gen 3 truck motor. I lined everything up (trans to block) and measured how much engagement the input shaft would have into the crank by measuring how far the input shaft surpassed the front edge of the BH using a long straightedge. I then measured from the face of the block to the crank hub to see how far it stuck out. I drew all this up to scale and determined an extended bushing by about .5"" would be ideal. Unfortunately, all the drawings I had for this were lost when my computer crashed last fall, but I see I attached it in my post on the above thread.

The closest I could come on this was an old school "extended" pilot bushing (it is like 1/4" longer, for a total of about 1") on eBay. It was a real tight fit in the crank. I used a stock LS1 flywheel and LS6 pressure plate with an "eBay special" clutch disk along with a mid 80's GM truck bellhousing since the pattern was the same for the 4 bolts on the tranny and as mentioned above all but one bellhousing to block bolts.

I don't have much time on the combo, still working the bugs out, but the clutch setup has not been an issue other than neededing a larger bore MC over what the Toyota had.

Eddie 70

iTrader: (3)

Thanks for the reply. Nice work on the drawing. I may have to do a little ebay surfing for the pilot bushing. Corvette Expo is coming up pretty soon here in Knoxville and I will get a chance to finally pick me up an LS motor and get this project underway.

69blackwidow

iTrader: (1)

hey eddie, the part #for the long pilot bushing i used from day motorsports is pb-6500. its $10.99 mike

Eddie 70

iTrader: (3)

Thanks for the help Mike. Great help like you guys are giving sure does help make a project like this go a whole lot easier.

jeepinpete

Per the GM Racing LS1 Installation Guide, use pn 12557583 pilot bearing. This is a sealed ball bearing that fits in the larger counterbore in the crankshaft.

V8 Supra Builder

iTrader: (37)

This may not fit with what you want to do. Per my research in the other thread:

I suspect your Keisler tranny is a Tremec series similar to my TKO600, if this is the case, the 12557583 inner diameter is way too big for your input shaft. The 12557583 appears to be used in truck applications that use a larger input shaft diameter than the T56 or old school style trannys. The LS1 T56 pilot bearing is shown to be .600 inch ID, 1.096 OD, .720 inch thick.

You should go by your Chevy dealer & see if they have one on hand that you could measure.

Eddie 70

iTrader: (3)

You are correct in your assumption of my transmission. It is essentially a TKO 500 with Keislers mods that make it fit the corvette without cutting the corvette in any way. It comes through the floor in the stock location. Very nice fit and looks stock, another reason for me wanting to use the Keisler with the LS1.