Max valve size for 4.0/4.6 heads?

[BlownMGB-V8]

Might be. My heads are at the shop to be machined for final assembly using the PAC springs. Might be done in a couple weeks.

One of the advantages of staying close to stock height is not having to shim the rocker pedestals to maintain geometry but the longer stems on the valves in my TA heads did not cause much of an issue fitting under the MGB repop valve covers so clearance doesn't seem to be much of a problem. Just had to trim a small notch in the boss for the oil filler plug to clear the chevy stud type adjusters. To go over .550" lift I'm sure a longer valve is needed though. I agree it took a lot of effort to get here but I sure do appreciate your help. I have that bottle sitting on the shelf, the car's back together and all we have to do is figure out the schedule to make that visit happen.

Jim

[BlownMGB-V8]

Still need to do the rocker shafts. These will go on the 340. I still need to order the cam and main bearings but it will go back together this summer. I have the options of using the old intercooled blower intake, (too tall) an iron 4bbl intake, making a new blower intake, or using spacers with a 300 intake. I'm leaning towards making another blower intake. Maybe I'll post the old one in the classifieds or something.

Jim

[mgb260]

Jim, what installed height, and pressure closed and open did you end up with?

[BlownMGB-V8]

Dustin did the final assembly so I really don't know. He told me he had to cut the pockets .050" deeper and used a .015" steel shim for a seat. Had .600" range of motion so my .550" lift is OK. Had to cut the guides .150". Installed height should be around 1.7" but I'm not taking it back apart to check. He felt the open and closed pressures were appropriate for a solid lifter cam, and from earlier calculations I think probably around 350 open and 150 seated. I think those were about the numbers he was throwing around. Really my only complaint is that instead of ordering the pocket cutter for the LS springs he used one he had and it cut the pockets bigger than they needed to be but they won't dance around enough to contact the seals so I think it'll be fine.

Jim