[jdw_poncho]

Any thoughts to adding some lightening holes? Thanks for the efforts.

[gavin]

I just unwrapped the latest laser cutting and have found I did not tell brent to change the hole size from the chev 2.992" to the pontiac 3.25".Its a good thing laser cutting is cheap It will only put us back a few days but I am upset with my self.Any way sorry Bruce but it is coming.

[BruceWilkie]

Just walked by my engine stand and realized that the Chevy 6 starter might be useable. Hole in adapter plate would have to be large enough for starter nose including mount flange. The pilot plate would have to be on transmission side. Pilot stop would then be at correct depth(as long as adapter is 1/4" thick). Maybe mock up the "mistake" piece and see?

[gavin]

That was what I was thinking Bruce waist not want not.At a later date we might draw up the bits and do it properly.Sorry about the hold up on our project but brent will send it in a few days as I will be back in my indian ocean purgatory.

[gavin]

Ok first up sorry for leaving this for so long as I have spent little time in brisbane for the last few months.This basically is the finished item and its just a case of showing how it all bolts together.First the adaptor plate is placed on the block and then the late flex plate note the spacer that goes over the crank centre first to correct the early to late size difference.The 55-60 starter then has the adaptor bolted to it so it can be bolted to the 61-64 starter holes or you could use the other spacer on the drawing for the 61-64 starter.

[johnta1]

Looks great!

[gavin]

You will notice the 3/8" rod used to set the starter in the correct spot as suggested by bruce.As it happens the starter was correct as bolted in the holes in the plate so no ajustment was needed.The dowel holes will be added to the adaptor plate drawing and the way to use them on the 55-60 starter is as follows.pull your starter apart and remove the pinion return spring and bolt your starter in position with the pinion extended.Check the pinion to flex plate to see if it spaced correctly(a paperclip is about right).If it needs moving use a round file to elongate the bottom hole in direction needed.Then put it back together and check it again.When you have it right tighten the bolts up and use a hand drill to drill through the adaptor plate and into the starter adaptor but not right through.Take apart and drill both plates to 3/8" you now have your holes to weld your dowel into.When you bolt the gear box on you can see how close the flange on a chev box is to the starter snout.You may have to grind a notch in the flange and on a p/glide you may have to do a small amount of grinding near the uper bolt hole .On a t/400 you will need to notch out as marked for the starter bolt.You could use a c/sunk bolt but you would have to remove box to change the starter.

[gavin]

Looking at it now you could put a stud in the adaptor plate and have the nut on the starter side.I missed a couple of pics I will add now them now.Sorry spell check not working. I still have not got pontiac box to bolt on but I think its not a problem.First pic p/glide flange second pic t/400 flange third pic cut down converter to suit early centre.

[BruceWilkie]

Gavin thanks for bringing this back up. I've had little time myself...then it got HOT and muggy.

I made a slightly different starter adapter plate for my early starter. (Temporarily its aluminum but was easy to work with home shop equipment)

Anyway the starter(using the early starter) and its adapter can be removed as an ASSEMBLY then starter can be removed from starter adapter plate.(removing or modifying transmission NOT required). Tested both BOP and chev T400's

My starter bolts are countersunk allen bolting thru starter adapter plate holes .

Securing starter and its adapter to the engine adapter plate....the upper fastener is a stud in 61-64 big car starter hole on engine adapter plate (faces front of engine)and requires a 7/16 thread 12 point nut (1/2" box wrench) for comfortable working clearance.

(Fwiw the contact area is the same as an 11/16" 8 point nut which makes wrenching slow and challenging)

A 7/16 stud on starter adapter (facing transmission) comes thru the lower 61-64 big car starter hole on the engine adapter. I used a 12 point nut there as well so you can use the same wrench you used on upper nut(12 point 1/2" box wrench).

The modern flex plate cover needs trimming to clear differences but will otherwise bolt on.

61-64 big car starter came in two varieties. The common solenoid high version has a threaded hole in upper position, you'd need a hole in trans to access it. The less common "upside down" or "421 starter" will bolt on. I've seen the upside down starters on 2 64 389 Bonnevilles so it wasn't exclusive to 421.

Delco only offers the solenoid high as a reman. 55-60 starters are easier to find at part stores.

BEST starter option IMO is the IMI 61-64 big car mini starter(Butler). RARE also offers a mini for 61-64 and it offers more clocking options.

Headers(common apps) may need some mods to avoid starter interference or just too close to solenoid (heat concerns). The mini starters should resolve that.

My 58 starter and adapter clears the kick-out on my Canton pan but header tube(old 3 tube) touches solenoid.

I'll post pics later.

[BruceWilkie]

BTW my 59 crank was machined for a large roller bearing so I need to bush down to standard convertor snout.(or use a modern crank)

My "prototype" aluminum starter adapter would not be adequate for long term use as you can't weld in studs.(1/4" plate with 7/16" fastener is not adequate thread engagement IMO)

Doweling starter adapter to engine adapter insures everything lines up after an R+R. Tightest dowel fit is achieved by drilling smaller than dowel and reaming to light press fit. Loctite on one end keeps you from losing dowels.

[BruceWilkie]

Here are some pics

[BruceWilkie]

More pics

[BruceWilkie]

more

[BruceWilkie]

one more

[BruceWilkie]

BTW the allen head countersink bolts I used are hardened bolts. The hardware store only had them in full thread 1.5" so I shortened them to what best fit.

Some pics show thick adapter in steel... I was looking at best engagement vs starter stickout. 1/4"seems fine. I used aluminum because of time.(perfecting starter pilot hole was time consuming with tools on hand. I rough cut steel with plasma cutter then routed rough edges with carbide rotary file in a router. It should be steel for reasons mentioned in post 90.

Aluminum was much quicker drilled a hole and used wood bits in my router.

I have my block nose down with crank installed in decent used bearings and plenty of grease. The starter engages clean and sounds fine spinning the crank. Normal wear on both flexplate and ring gear my clearance is about .030". You should check clearance in several spots to account for run-out.
( I also found out I had two used flexplates that were bent! They went to scrap.)

[BruceWilkie]

I highly suggest not creating your BOP/Chev dowel holes till last. (Chev and BOP share same dowel hole locations)
Use a stick "modern" bell housing(borrow or buy a used factory piece) or if you have a junk t250/350 etc you can cut up(cut so pump hole remains. Pump hole is bigger than stick pilot, making it easier to set up dial indicator) use a dial indicator to center the housing for no run-out. Clamp it down and use dowel holes in housing as a guide to just START your dowel holes.(you can use a light hand drill if you grease the bit. You only want the bit to start the cut) Finish the dowel holes on a good drill press thats square to bit has no slop in head and a drill bit that has no run-out.(cheap bits or slop in press throws accuracy off).

[gavin]

Good point on the dowel location I must admit I have not checked mine with a dial indicator I will check later.And yes I have two different thickness plates to play with and the 1/4" does have better engagement.I will get back later with the dial indicator results and other missed details.

[BruceWilkie]

btw see the bare metal on block. Its been bare at least 5 years. Plenty of other stuff in shop has rusted nearby. Lots of nickel is obvious.

Early blocks TTF!

[Jack Gifford]

Nice work, both Gavin and Bruce!

[gavin]

The runout was .031 on my rather rough setup. I may have to find another case as this one has been weld distorted witch is why it ended up on my junk pile.However if correct it makes it about .015 misalignment and that's too much.Perhaps you can add bellhousing alignment to your video.