Northstar Engines and System Technical Discussion Discussion, New Studs to incorporate alignment pins in Cadillac Engine Technical Discussion; Just thought I'd post this to let everyone know I've got another order of studs placed that will incorporate the ...
Just thought I'd post this to let everyone know I've got another order of studs placed that will incorporate the alignment pins in the stud.
There is very little movement of the head once you slide it over the studs but some customers have asked that I modify the kit to allow for alignment pins to be re-installed. I've done one better- four of the studs included with each kit will have the pin machined right into the stud. The alignment pin is just a tad shorter than the original in case of installer error (I don't want the heads tightening against the pin) but is still there to hold the head exactly where it needs to be.
The order has been placed and the CNC machine is working on it. These new ones will be available soon.
The original alignment pin diameter has been retained and with careful drilling and tapping using the jig provided, it will be an accurate fit just like the factory pins- I've tested this to be sure.
I have 13 sets of studs left as of now, another 50 on the way.
I will post photos of the new studs once they arrive.
Hey Sub have you ever heard of the DOHC 32 valve Olds 455? I heard there was a prototype built back in around 1970 that was producing around 700+HP. You know those engines better than anyone else I know- do you know how many were built and if there are any left out there?
It was a prototype, there were a dozen or so built, and the entire chain-based cam drive system was a Rube Goldberg arrangement. Incredibly complicated. Joe Mondello tried to get GM to keep at it, but it was just too finicky and expensive, even in '69. I doubt that any survived. I heard that they also fooled with a SOHC head, sort of like a pent-roof hemi setup. Oh, don't I wish.....
I just picked up a 1970 long block 455 with unknown (a LOT) hours on it and the cylinders have no wear, no taper, and no ridge. I'll lightly hone it and stick in a set of stock bore pistons with moly rings. The heads will need hardened seats, but it will become a 525 hp RV engine. Forged crank, too. Roller, rollers, Keith Black, my Quadrajet, MOROSO, Melling, Comp +4 degrees. A stump puller. ALL the torque will come in from 2,200 to 4,000.
Automobile(s): 1997 ETC (GAVE TO STEPSON 2011), 2000 DTS (RIP)
FOUNTAIN HILLS, AZ
Re: New Studs to incorporate alignment pins
How come the original alignment dowels can't be reinstalled? Are the studs too large in diameter? It seems like the drilling and tapping will have to be done carefully and accurately with the new design, as you stated. I don't think the Norm's setup I used would be precise enough - one or two holes appeared a little off center at the bottom - hard to explain - those of you that have done them know what I mean; there was ample slop in the head bolt to head fit, and I re-installed the original alignment dowels, so there was no problem. Oh, that was 2 years ago - before your system was announced.
The alignment "pins" are hollow sleeves through which 2 head bolts pass. The "pins" are pressed into machined recesses in the block, and mate with respective machined recesses in each head. 2 is all that are required.
The new studs will have a machined "shoulder" at the block surface on the proper pair, which will align with the head recess. Instant alignment within .002".
Think of the proper slot keys in your water pump removal tool.
Nope- the top 2 corner bolts on each head have alignment pins as Sub said, with the bolts passing through. The studs are too great in diameter, very very little, to use new alignment pins. I would have to machine the threads down a bit to re-use alignment pins. This way it's all in one unit. The studs all have two inches of firm grip in the block, except for the four corner holes where the alignment pins once were. The nature of the engine only allows about 1 1/2" of thread holding on the studs in these four holes. I had some other options when I designed the studs but I wanted to keep the threads as close to the top of the deck as possible. There is more material in this area and less of a chance for coolant to get around the threads again.
All of the studs are the same depth in the block, 16 have 2 inches of firm grip, and the other four have approx. 1 1/2" of grip, now with an alignment pin machined into the stud. The difference in hold from 1 1/2 to 2" is minimal and will never cause an issue, since 1 1/2" of M11 fine thread was the factory standard and since most of the threads that get eaten away from porous blocks are in the lower bolt holes. The 2000+ blocks hardly ever have coolant on the threads at all.