[Tom Vaught]

Originally Posted by Rar_421

Had no idea Tom was involved with Pontiac projects,he was very well known for his work with Kohler snowmobile race engines with Rupp and the Kalamazoo Kyotee sno pro sleds,I've been collecting parts to build a Kalamazoo Kyotee replica

He ever take you for a ride in his 1000 hp chevy Pontoon Boat??

Tom V.

[spectramitch]

The dowels in the block are .308 DIA and the New billet caps came reamed already to .312. The new caps should just drop on with slop, they do not. It seems like the spacing between dowels on PMD is not the same as the billet. Has anyone encountered this? It sounds like I need to re-establish location with a mill cutter and maybe open up to 3/8" dowel and not just re-ream the block holes.

[krisr]

Originally Posted by mgarblik

I will add, when drilling or taping stainless steel, use Elmer's glue as a lube. Just the plain old white glue! Sounds crazy, works beautifully. I don't know why. Friend who owns a sheet metal shop showed me that.

I've never heard of using Elmers for a tapping lubricant in SS! I'm guessing you see much more tap life with it?

[mgarblik]

The biggest difference I have seen is when drilling SS with high speed steel or cobalt bits. The glue doesn't let the bit overheat and the SS doesn't turn blue like it often does. Use the glue and moderate to slightly high constant pressure and it drills right through. Again, I don't know the science behind why it works, but it does.

[shermanator2]

Originally Posted by spectramitch

The dowels in the block are .308 DIA and the New billet caps came reamed already to .312. The new caps should just drop on with slop, they do not. It seems like the spacing between dowels on PMD is not the same as the billet. Has anyone encountered this? It sounds like I need to re-establish location with a mill cutter and maybe open up to 3/8" dowel and not just re-ream the block holes.

Stock Pontiac dowels are about 0.3096" diameter. With the Milodon splayed caps that I have, a 0.3096 dowel will drop into the holes, but a 0.3125 is not even close to fitting.

And BTW, I have bought dowels from http://www.precisionautomotivespecialists.com/. That is the only place I have found proper 0.3096" dowels. I also like the extra length of his.

[Skip Fix]

Originally Posted by spectramitch

The dowels in the block are .308 DIA and the New billet caps came reamed already to .312. The new caps should just drop on with slop, they do not. It seems like the spacing between dowels on PMD is not the same as the billet. Has anyone encountered this? It sounds like I need to re-establish location with a mill cutter and maybe open up to 3/8" dowel and not just re-ream the block holes.

Yes the 400 block I had converted the shop id not really check fit. One of the billet caps drops on the other 2 are tight as the spacing must be a hair off.

[spectramitch]

Current Progress, I think the fixture is coming along nice. Now I need to pick up locations of dowels in the block and in the cap to figure out what amount to move holes to get back in line with each other. I am going to try to make 8mm dowels work.

[spectramitch]

I made the plates able to hold the block square and at 18°.

[67Fbird]

Looking good! Alot of work for a 1 off project but moving rather well. Is that couple of injection molds i see laying around?

[Scott Stoneburg]

Nice work!

[spectramitch]

Originally Posted by 67Fbird

Looking good! Alot of work for a 1 off project but moving rather well. Is that couple of injection molds i see laying around?

Thank you, yeah its a bit of work but I am sure any engine machine shops near me would have totally hacked this thing up. Good eye those are some molds back there. Its crazy how many guys I work with making these custom molds and none of them have any idea what they are looking at when they see an engine block. One guy asked me “what are you doing for the exhaust there?” I said “what exhaust?”, as he pointed at the 3 freeze plug holes lol

[Tom Vaught]

A lot of different knowledge levels out there. Congrats on a very nicely engineered fixture to drill your block.

Are you using bushings in the outer main caps holes to help locate the center lines of the drills when doing the initial small bit drillings
in the block?

Tom V.

[spectramitch]

Originally Posted by Tom Vaught

A lot of different knowledge levels out there. Congrats on a very nicely engineered fixture to drill your block.

Are you using bushings in the outer main caps holes to help locate the center lines of the drills when doing the initial small bit drillings
in the block?

Tom V.

I did make a drill guide ‘sleeve’ to fit inside the splayed hole and have the ID be the tap drill for 7/16-14. I was going to use that for if I had to use my bridgeport with the head tipped. Now that im doing it in the cnc. Im not sure if I am going to use it or not because I am planning on installing the caps on dowels with block set on the 18* fixture side. Then tramming center zero in cap and spot facing, center drill, tap drill then tap.

[Tom Vaught]

Thanks.

Tom V.

[spectramitch]

I have the new dowels installed and they fit very nice now. I have layed out the thrust 'step' dimensions. I will do a rough cut and re-install and make sure measurements are lining up before finish cut.

For drilling the 18° holes, how deep until the water jacket becomes close?

[Tom Vaught]

http://forums.maxperformanceinc.com/...22#post2332622

All the info you need is here.

Thanks to Pontiac Jack and others.

"You don't really want .001" interference fit in the block. A "light press fit" is called for, which means very close to a "zero" fit. Usually the first 1/4" or so of a reamer is slightly undersize (some fraction of .001") and gives the fit you want.
You also don't want a 34mm long dowel- more like 5/8"-3/4", with more than half of it into the block. You could shorten them with a cut-off wheel, then grind a little chamfer on the cut end." Pontiac Jack





Tom V.

[shermanator2]

Out of curiosity, do you race guys use dip sticks? Or do you just assume no significant oil is lost between oil changes or tear downs? The reason this matters here, is that I have not figured out a dip stick solution that works with splayed caps. The stock dip stick would route through the splayed bolt. Something through the side of the pan could work.

[AG]

I don't use a dipstick on my race motor and it does not leak oil at all. I change the oil frequently enough it's not an issue.

[Dragncar]

Originally Posted by shermanator2

Out of curiosity, do you race guys use dip sticks? Or do you just assume no significant oil is lost between oil changes or tear downs? The reason this matters here, is that I have not figured out a dip stick solution that works with splayed caps. The stock dip stick would route through the splayed bolt. Something through the side of the pan could work.

The only way as far as I know is to install one on the side of the pan. Canton makes a weld in version for their pans. You could adapt it to any pan if you wanted to bad enough.
I has Steffs weld in a bung for this on my aluminum pan I bought from them.
Not sure if I will even use it as there are plenty of knowledgeable racers getting by without any dipstick at all.


https://butlerperformance.com/i-2445...tegory:1285261

[73 TRANSAM]

What I did on mine is to weld 6AN fitting then use a braided line then cut it to length for the dipstick to read correctly. This way its flexible enough then when ur done, just cap it with a 6AN plug. Incase ur running a vacuum pump.