Beating a dead horse? Bore x Stroke x 300 heads

[phongshader]

Carl,
I found them here: https://www.uempistons.com/catalogs/silvolite_catalog.pdf pg 78
I would think that with the valve reliefs in the piston I might get a cc or two of piston volume to lower the compression a bit. I get 10.8:1 on the UEM calculator with 0 piston volume but I think I can pick a cc or two of piston volume from the valve reliefs, I'll say 2,and with that extra volume drops the CR to a more manageable 10.5:1 There's another piston listed in the catalog identical to the 1758HC, the 1765HC that has a about a 6cc dish which would drop the CR to around 10:1. I just haven't been able to find some one who actually sells it.

I see that you already found the catalog

[MGBV8]

Yeah, I found it in the catalog.  I have been wearing that website out for many years.  I put Keith Black 11:1 pistons in my Camaro 25 years ago.

I was just surprised that searching for your part number returned " There is no product that matches the search criteria."

Usually you can get info like this.

https://www.uempistons.com/index.php?main_page=product_silvolite_info&cPath=6_25_26&products_id=6408

[phongshader]

That's where I got my Olds pistons 25 years ago.
I looked through Chris Gill's build on MGEXP to try and get some info on his valve setup but it was very thin. Do you, or anyone, have any info/part #s on his setup? How do the stock valve length compare to the Chevy valve lengths?

[mgb260]

Justin, I'm the one who recommended the GM 2.8/3.4 V6 valves for Chris's build. I assumed he would get new seats for the valves. Looks like he cut the diameter down to use the stock seats. About the same as the larger valves you listed. The ex valve is .030 longer and he uses custom length Smith Brothers pushrods with upper tip 215/300/340 ball size and lower 350 Buick ball size for though the pushrod oiling with 350 Buick lifters. The shim under the rockers is for geometry for the longer valves plus blocks the head oil hole.Info on this page:

http://www.mgexp.com/phorum/read.php?40,2598435,page=5

[phongshader]

Jim,
Thanks for the additional info. This just confirms my choice to go with the V8tuner valve set. With the exception of enlarging the valve seats it's pretty much a straight swap, well maybe new exhaust valve seats.

[phongshader]

Reviving this thread, I'm looking for a good head porter in California to do up my 300 heads. Any recommendations? I'm in the SF bay area and I'd prefer not to ship them to Missouri to get the work done.

[phongshader]

Wow! No recommendations for a west coast shop to port some 300 heads? All right how about recommendations for any shop to do up some 300 heads?

[roverman]

" Mc Kenzies" ,(spell check), north of Oxnard, CA., ported my Merlin F85 heads,(Real Steel). They flowed quite well throughout the lift range.  Spec's are posted on this site.  I suspect also, "West Coast Racing Cylinder Heads", would perform good porting.
                                                                                                                                Good Luck, art.