Looking to start my auto to manual conversion and came across a few comments about the back end of the crank in an "automatic" engine not being drilled to accept a pilot bushing. Does any one know of a way to check from the vin or some other number on my original '76 L-48 engine to know beforehand that the engine is compatible with a manual trans? Thanks, joe

 

I do not know the answer but about to start the same project and concerned about the same thing. I do have the benefit of a very gifted machinest friend around the corner from me(Norval ) who will drill it out if we have too.

 

I assume your car is automatic and doesnt have the clutch support bracket on the frame. Are you going to go with a manual or hydraulic clutch?

 

Yup, I am going to use a camaro bellhousing with the slave on the side. I have original clutch linkages but do not want to fuss around making a mount on the frame. I am using the Ford T5 with an adapter plate. What are you going with?

 

Sounds like you have been talking to Norval!
He recommended that to me when I first started. I was concerned about the offset (twist) in the camaro bellhousing and the resulting placement of the shifter.

What shifter will you use?

And the next big question is what master and slave cylinders?

I am at the point where I need to make a decision on hydraulic or manual clutch.

I did acquire a bellhousing from a mid 80's GM truck. My Super T10 bolts right to it without a twist or offset. I am not sure at this point if it will work. The stock throwout bearing arm interferes with the bell housing where the slave cylinder attaches.

 

A clutch master from a 85 one ton truck bolted directly into my 75 without drilling any holes. The original plate covering where a manual rod would have passed through had all the proper holes. As for a slave cylinder whatever bellhousing you choose that is the slave cylinder you want. To join the 2 use a simple brake line.
As for the offset built into the bellhousing to roll the transmission over when I make the adaptor plate I roll it back so the transmission sits straight up.
My donor bellhousing was also the 85 one ton truck but I wanted to run the 11 inch clutch with a 14 inch steel flywheel.

Coleman sells a really nice remote resovior for the clutch.

 

Forgot. If Doug's crank is not drilled I will build a nice jig that allows you to drill it with a hand drill. The jig centers the drill bit and holds it in a sleeve perfectly centered and at right angles. I never heard of this before, don't expect it to be a problem but am ready to remedy it if that is what we find.

 

In my case since I am using a spacer plate the camaro offset bellhousing is not an issue at all...we will just drill the spacer so that it is straight up. But I can see why you would not want to go that way with your trans.

I am using a aftermarket T5 shifter that has a bolt-on stick...that way I can modify or fabricate the stick easily for a placement that works for me. I may even modify a stock vette stick.

I have not purchased the clutch hydraulic master/slave cylinders yet. However I plan on buying them new for the same camaro that the belhousing came from. The only question that I have yet to nail down is what the master looks like and if I will I need to modify it in order to bolt it in. If it needs a lot of mods, I will use the 85 truck master since Norval already found that it works well.


On your bellhousing clearance problem, I am wondering if you could use the stock arm from the truck rather than the vette.

I am using a T5 from the 94/95 mustang which has an even longer input shaft than older models. This will mean an even thicker spacer plate that will place the shifter in almost the stock location(from front to back). However I will need to build a dog leg into the shifter handle mount in order to move it closer to the drivers side of the car in order to avoid mods to the console which I really want to avoid.

Question....is your truck bellhousing the larger style housing for the 11" clutch, or is it the smaller one for the 10.5". I recall that Norval had to deal with some minor tunnel clearance issues when he used the larger version.

 

Doug I took my flywheel with me to the wrechers. The first pulled a camaro bellhousing and when we tried to fit the flywheel in it the bellhousing was too small. We then pulled the truck bellhousing and it had the proper clearance to run the larger 14 inch flywheel. You need the 14 inch flywheel to clear the 11 inch pressure plate and clutch disc. I would go with the smaller flywheel and a 10 1/2 inch clutch.
Yes the slave cylinder lightly touched the floor so I just cut and refiberglassed a small area for increased clearance.

 

 

I believe it is the "large" bellhousing. It takes an 11" clutch and has 168 teeth on the flywheel. The diameter from end of tooth to the opposite end of tooth is about 14 inches. It seems to fit into the bellhousing without any problems on the bench.

The top half of the bell exactly looks like the shape of corvette bellhousing and it should fit within the body. From the first starter bolt downward if differs.

It looks like it takes a starter with a really really big snout and not my stock starter off my 76.

I will post some picture of the bell a bit later ....worth a thousand words.

I have to pick up the 85 truck master and slave to see how well they mate to the everything. I have seen pictures of the master and it looks like it is designed for a firewall with much more of an angle than my 76.

I do have the truck throwout bearing bracket. It might hit the floor as Norval mentioned but I can deal with that.

Keisler has a master that is a direct fit. Looks to also have support plates for the floor to beef it up. Try and get one out of them without buying a whole conversion.

I have all the parts to use the manual clutch linkage including a bracket for the frame but I would need to get it welded to the frame. On my car it looks like there brake lines all in the same spot. It doesnt look like it would be easy to do without removing the engine.

 

I just did another conversion from auto to manual. This time I used all the parts from a 91 Camaro witht he T5. I used the stock Camaro clutch master and slave cylinder setups. I used the stock Camaro starter. I also used a Centerforce clutch setup for a 91 Camaro. Because 86 on 90 degree Chevy small block crankshaft bolt patterns differed from the pre 86 crankshafts, you cannot simply use the 91 Camaro flywheel. The Camaro bellhousing uses the smaller GM 153 tooth flywheel, so I had to order a Hays 10-330 internal balance flywheel.THe stock TH350 style trans yoke fits the T5 and I even used the stock vette driveshaft. The shifter even bolted into the stock location with no problems. Everything simply bolted in with no problems. I did have to do some floorpan clearancing for the slave cylinder. But that was easy. Good luck!

 

Never seen that....

 

me neither....all pre 86 small blocks that I have seen had the hole for the pilot bearing.

 

Well that's a relief........could just be an urban legend floating around the discussion boards.

 

sorry for the double post

 

SHARKY..This is helpfull..Thanks. Assuming that you did this conversion on a vette....Did you have do any mods to hook up the master? Do you see any reason why a stock vette flywheel would not work? I am surprised that the shifter ended up in the stock locations...throught the GM T5 puts it toward the passenger and the front.

 

I have a line on a complete 86 camaro t5 setup to convert my 79 and am also curious as how the shifter comes thru.
Chris

 

SHARKY,do you have a ballpark cost on that conversion?

 

I bought the 91 Camaro as a parts car at a cost of $1500. Last year, I bought a T5 trans, from bellhousing and flywheel to tailshaft including clutch master and slave cylinders and pedals for $1200.

I am sure that if you go to an auto wrecking yard, you might find a better deal. The last time that I went to a local yard, I saw three possible manual trans donor cars.