FINAL BUILD no 302 heads

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quick maybe dumb question

do i have to zero deck the kb107s?

or can i jsut run them with a .050 deck clearance
and a .020 gasket and run at 10.1 compression with a 72 cc head
 
If you have 0.050" deck clearance your compression will be 9:1.

As I stated in your other post if you can't afford to do it right I would recommend that you just re-ring the the engine and run it until you can afford to do it right.

You are NOT going to find any one recommending all the short cuts to doing it right you propose as a good way to go.
 
dgc333 said:
The shop that did the machining on my block had a machine that registered off the center line of the mains and cam. If they were machining the decks they couldn't help but square them with that machine. This same machine was used for the ruff boring prior to the finish hone with deck plates.

It cost me just shy of $1050 to have the block cleaned, magnafluxed for cracks, the cylinder walls sonic checked for thickness, the mains checked for alignment (didn't need to be machined), bored, decked, finished honed with deck plates, new cam bearings installed and painted. This cost also included balancing the rotating assembly which needs to be done with the KB107's because they are so much lighter than stock. I had had the crank cleaned, magnafluxed, turned 0.010/0.010 under and polished prior to bringing in the block which was $250.

If you do not have the money to do it right it would be more appropriate to just rering and regasket the engine and run it until you have the money to do it right.
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Dave,
This isn't totally true as there are shops around here that have the same type of machines and the block was returned in worse shape than it was taken to them. As over time the machine that they use had some ware in the fixture, and clamping devise and being this couldn't square a block any longer. Another thing is how can they adjust for a block thats out .020-.030 from end to end and the mains are straight, as the factory cut should have taken care of this but didn't, if what your saying is true. After being so discouraged I built my own tooling and did it myself, and will outlast the machines with more adjustability and accuracy.
And thats a good price on the machine work that you had done.
 
The only way a block can be square decked is if the mains are attended to first. Regardless of fixture manufacturer, they all use the cam bore centerline, and the crank bore centerline, to set up the deck height. So, you can chuck a block up on any milling machine with a BHJ style fixture, but if the mains are not corrected (and we all know how good factory machining is in terms of accuracy) the deck may be flat, but if wont be parallel with the crank centerline. Similarly, the same equipment bores the holes. So while the block is in the fixture, all 8 holes are bored exactly spaced properly, and exactly 90° to the deck and crank centerlines. Like BJR said. You either do it all, and do it right, or you dont, and IMO anyway, waste money. Old school horizontal millers cannot square deck a block. They dont have the capability to cut the surface as flat in terms of right to left as opposed to front to back, or with the right finish for modern MLS gaskets either. If you look at the milling equipment, and it has a round disc with cutters evenly spaced around it, and a large arm that the motor and wheel are mounted to coming out of the large flat table, walk away. It's fine for rebuilding flat heads, and stovebolts, and farm equipment. It has no real value in a modern performance automotive machine shop. In fact, the shop that just closed trhew one out because no-one wanted it. When I rebuild an engine, any engine, there are certain things that get done regardless of output: the usual cleaning/magging, then (in this order) align hone the mains, bore, square deck to set my piston's installed compression height. In the shop I recently switched to, that's all done on a CNC Rottler F-65A. Attached is a pic of the fixture in use on the manual version F-65M where I had been going. Not the cutter is sinlge, the round disc is a shield. The spindle speed and feed rates can be set +/- 1rpm, from 0 to 3000+ as needed. That's where the surface finish for Cometics and MLS gaskets come from. Old millers cannot control the speed well enough, and because the flat disk has to be angled slightly so only one side cuts as it crossees the surtface. So depending on diameter, the center of the sweep will be cut slightly deeper than the edges. (think about the ride at county fairs where teh people stand up, and it spins, then tilts. The cutting hed is tilted the same way. When you shoot for demensions for quench of exactly .035 and the outside of the deck is flat, the center (between the cylinders) is .002 deeper, that dip can be a pain to account for and a gasket sealing issue. That sounds anal. But things like this are the difference between a performance build, and a repair back to stock factory shape from wear.

Sorry for the ramble attempt at clarifying. The reason the "old guys" say dont bother, is we've spent the money, and found out that for what you are intending, you dont have to spend or make that effort. You can always say "but I want to to be right". But sometimes, factory is good enough. Your's is one of those cases. And truthfully, I've had less trouble from junkyard jewel spray cam rebuilds with a cam, than some top dollar build ups. Spend if you want. You're headstrong and will do what you want. Just try to understand the reasoning behind the advice.

rottler2.jpg
 
The equipment that was used to deck my block looks very much like the one in the picture moper posted. This place has an excellent reputation in my area and specializes in high performance and odd ball engine work, he does the engine work for one of the local top alchol funny cars. Looking at this guys shop and how he keeps it I can't imagine him allowing any piece of equipment to wear to the point it can't do the job right.
 
I guess I should have said that it has more to do with the operator running the machine and who set it up than it does with the machine it self.
But I've still seen machine work like I stated on some fairly new equipment, and the machinist said to me and the owner of the place that it wouldn't cut any closer than what it did and then he told me that the engine wouldn't ever see it. Believe me I got out of there as fast as I could and laughed for the next ten or so miles.
 
I did end up remachining it my self, and I didn't take it there to start with as it was someone else block.
 
dgc333 said:
If you have 0.050" deck clearance your compression will be 9:1.

As I stated in your other post if you can't afford to do it right I would recommend that you just re-ring the the engine and run it until you can afford to do it right.

You are NOT going to find any one recommending all the short cuts to doing it right you propose as a good way to go.
Click to expand...





how do you get 9.1? i got 10.1 with the compression calculator from keith black
 
sorry i got 9.1 with 73 cc heads and a .039 gasket

i meant 10.1 with a .028 gasket at 0.050 and 73 cc head
 
wait can some one give a good calculator to use becasue i use 2 different ones and they gave me different answers
 
actually guys dont worry i found a machine shop in morgan hill that will do my motor and maybe my heads iono yet

but they will bore it hone it wash it, balance it and deck and square deck it
150 to bore and hone 60 to wash
200 to balance
and like 150-175 to deck
 
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