line bore/hone question

[gnbeginer]

can someone tell me the actual measurement between the bottom of the cam journal and the top of the crank journal. Had billet caps installed on block - suppose to be .002 cut on block but a stock t-chain fits it really tight. Wondering if shop really bored and honed caps to block.

TIA

 

[Franks86gn]

power source book says 4.335" centerline to centerline.
I just had new billet caps put in and he cut it .005" I had to use a bigger cam gear to get the correct chain slack. Stock one was way too loose.

 

[Franks86gn]

Measure from bottom of cam bearing to top of main bearing.
Measure ID of cam bearing and divide by 2, Measure ID of main bearing and divide by 2 and add those to your first measure.

 

[earlbrown]

A line bore done correctly will not move the crank up. A line hone will move the cenerline up right at 1/2 of what was removed off the caps.

If you have billet caps installed, the block had to be line bored to even put in bearings and a crank.

 

[Pronto]

I'm curious, once it's line bored with the billet caps in place, does it have to be honed as well?

 

[Franks86gn]

I'm curious, once it's line bored with the billet caps in place, does it have to be honed as well?

Yes
On my receipt it says "line bore & hone"
I think they run a rough cut through it and then finish it with a hone. If I'm mistaken, somebody chime in.

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[Pronto]

Yes that does make sense...

 

[SCOOBY DOO]

I'm curious, once it's line bored with the billet caps in place, does it have to be honed as well?

No.

 

[we4Mateo]

No.

Doesn't it need to be honed to get the cross hatch in the bore?

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[Franks86gn]

I don't see a need for x-hatch in the mains. Only the cylinders need that for oil retention.

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[SCOOBY DOO]

Doesn't it need to be honed to get the cross hatch in the bore?

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A skilled machinist can take the absolute minimum from the block...and take the rest from the caps. Align hone brings the cam and crank closer because it takes 50/50.

 

[coach]

The cut is pretty important, but not as important as the correct hone. The billet caps are harder then the block. It's kinda tricky to get it really nice. The block cuts way easier.


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[Nick Micale]

......... Had billet caps installed on block - suppose to be .002 cut on block but a stock t-chain fits it really tight. Wondering if shop really bored and honed caps to block....TIA

There is no fixed amount of material that is removed in a line bore so that dimension not going to give you any usable data?

Installing steel caps require a line bore because the steel caps are made oversize as the "register" in the block, and other dimensions, that hold the cap can vary.

Once the caps are fitted and finish installed with a line bore, an align hone is done to set final clearances and to have all bearing saddles in close to perfect alignment.

We never do ANY engine build without an align hone if steel caps are done or not. This is necessary as the factory tolerances are not held as close as ours, and block flex and working over time and use will change these very close tolerances. We want the crank and block bore to be as good as we can possibly get it for proper oil clearance and bearing life.

It is too late for you to worry about your machine shop doing the job properly. In very few miles you will see bearing material in your oil filter if it is not right.

This is why you should get familiar with the machine shop and person doing the work before you hand over $$$$, not be guessing at this point to wonder if he did it correctly?

 

[gnbeginer]

well - the crank is in the block - so is the cam. both spin freely. but what i am having trouble with is - what t-chain to use. I got a factory double roller and it fits on the gears tight. after calling the shop and talking with the shop manager and him talking to the machinist - it was said to be .004 cut on the block side. so am i missing something? all the searching i have done leads to having to use a .004 smaller chain/gears. So why does this stock double roller fit so tight? this freckin block is is about to be scraped.

correction - they said i need a .004 t-chain set

 

[Mike Licht]

in most cases when machined correctly an undersize set is not needed. Sometimes they are but it is pretty clear when assembled if it is going to fit or not

 

[gnbeginer]

startin to think ls swap

 

[gnbeginer]

startin to think ls swap

 

[earlbrown]

because the shop didn't screw up and move the crank centerline ?