Thread: drilling the VE head

we're going to be using a carbide slot cutter to drill the dowel holes out on my VE head, only problem i have is i need a 19/32" (which is 15.1mm) cutter but can i hell find one, the closest i can find is a 5/8" that is the same as or there around 15.7mm. with tolerances in mind etc, would the 5/8" be ok or does it need to be bang on? ive rang our local tools workshop and he said he was enquiring about getting one slightly bigger then modifying it to 15.1mm but has he got back to me...hell no! i know its only 0.6mm bigger which is bugger all, but in terms of head bolts etc...is it really bugger all :lol:

the dowel holes in the VE head are 13.6mm and the DET head came to 15.1mm which is yes 1.5mm bigger :roll:

cheers fellas

keep us posted on how it turns out

19/32" is equivelant to 15.081mm, so you're going to be off by 2 hundredths of a MM. I don't know how close it should be, so I can't answer that for you. I would imagine that it would be pretty damn close, if not perfect, though.

we are going to measure the dowels on the GTiR block, the holes in the GTiR head and the holes in the VE head again just to be double sure, i had another measure of the dowel holes in the GTiR head the other day and they came up at 15mm dead using the same vernier, im hoping that 15 turns out to be correct as that will be straight forward. i'll let you all know chaps

Short answer is 5/8 wont work it will be like a c*ck in a sock. Dowels are used for location so need to be pretty tight tolerance.
Why don't you drill them out to 14.5, then ream them 15mm, double or even triple check all your dimensions for both the holes and dowels, but i would say 15.00 would be more likely to be correct.
If i was going to do it i would be aiming for a tolerance of 15.00 +0.02, +0.05mm for the dowel hole. But thats the tolerances we use for dowel holes for our tooling so it may be a bit looser for a cylinder head. I wouldn't go more than +0.1mm on the dowel hole though.
Hope that helps?

I just re read you last post, are you talking about the two little location dowels that the head locates to the block or are you just talking about opening up the holes for your head bolts

Holy crap, all this time, I was on crack! I thought he NEEDED 15.1mm, and whatnot. That's why I was saying that .02 hundredths off should be fine.

Reading > Me.

Sorry for that! I guess what you were REALLY asking, was if a 5/8" drill would work, and I think not, as mentioned above. It's WAY to big, unless you plan on going with larger dowel pins, somehow.

Would this work?

http://www.tooltopia.com/index.asp?PageAction=VIEWPROD&ProdID=33172

I don't know where your located, but I'd imagine they'd ship just about anywhere.

thanks for that old chap, my friend is bringing his vernier down tonight to measure the dowel holes in the DET head, what ever they come up at thats what we are going to drill the VE dowel holes to. he mentioned that he has made some adaptors out of graphite so we will see if they work. i'll let all know when we have measured up again

well we measured up and typically it came up at 15.2mm with his newly calibrated vernier :o

we are sacking the drilling idea, custom stepped dowels are getting made out of graphite now, anyone know the size of the GTiR dowels, if not im taking them out tomorrow to measure up