Engine machine shop or more specifically, head work

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Joined
Aug 27, 2021
Messages
173
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Location
Williamsburg Virginia area
My Car
1972 H code convert., 351C 2V, FMX, 9in., Ram air, Pwr Steering, Pwr Disc brakes, air-conditioning, 15" sport wheels, Ivy Glo w/white deluxe interior.
Does anyone living in the Hampton/Newport News/Williamsburg area know of a very reputable machine shop to take their 4V hads to have work done?

As of now, they are completely bare, having been stripped of the valvetrain. What's know so far is they will need; to have them completely cleaned, Seats checked and refinished, valve stem guide bosses machined and new guides. On the new guides, can't remember the size that a friend suggested due to the need to machine but I'll hopefully have a reminder answer from him soon.

These are screw-in rocker studs so, actually thinking of having them machined to receive guide plates. However, this one is a wild card since the engine, as of this moment and not knowing the condition of the internals, I'm only planning a refresh with breaking any glaze, removing any ridge not too severe requiring a new bore, new bearings (checking clearances), seals and rings. For what it's worth, we're talking under 80,000 miles and comparing it to the 351w I did the same with way back when, it had considerably higher mileage and was driven by a then 17-year-old frenemy who did "drive it like he stole it" being it was a '69 Mach 1 and gas was still only $0.60 gallon.

We're not talking adding any horsepower other than what 4v heads, intake manifold, headers and carb will provide. The cam will only be a "nostalgia cam" Don't need it but having it sound great is a like.

Mentioned the valve stem guide bosses above, it appears as if someone before me replaced the guides but did a really half arsed job. All 16 are broken, not cracked and to various stages of chipping and many of the guides themselves, are not fully or properly installed. It's a shame, would have saved me a few steps but then again, I probably wouldn't have gotten them for the price paid. Seem to be allot of that surrounding this car, from the purchase forward. Lol. Have a pic of the issue explained below. Knew they were going to need work, but the new stem seals and old springs made it impossible to know this was the condition.

Thanks in advance. Hopefully I can get back here later today.

IMG_2286.jpg
 
That's a very easy fix. Whoever installed the guides didn't cut them down to 1/2" to clean up the "eggshell" left behind. That was a normal part of an install where I worked. The guide shows knurling...I don't recall for certain, but it seems like some guides came with a short knurled section to allow for a film of oil in that area....we didn't like that style, but I don't know if they are the standard, these days. If those guides are worn in excess, those can be driven out and a new set installed and reamed to fit. All very standard stuff.

Below is what the cutter looks like that they'll use to clean up the eggshell.

1708790461789.png
 
Good morning Cal 72,
Yes, your guides have been replaced at some time previous. Since the guide boss is cast originally with a taper towards the top from the factory, the old material will crack away when drilled and reamed for replacement guides as pictured. Most all reputable cyl head machinists will completely machine away the old guide casting to avoid this, and it is necessary to do this when installing teflon PC seals. I can see knurling on the I.D. of your guides, some replacement guides come this way new out of the box, some are totally smooth internally, then again, sometimes a machinist will cheap out and knurl an already replaced guide. In any case, you're all apart, it doesn't get any easier than right now to go ahead and have new replacement guides installed, and have your machinist machine away the broken original remnants of guide down to the raised locating pad. If you are going to run a "stockish" hydraulic cam of conservative lift and stock springs, there are kits that utilize 5/16ths screw-in studs and guide plate inserts with nylon guides to hold your non-hardened pushrods in place. These "Bolt-in" components are totally acceptable in a stock or mild application, and will save you the expense of completely changing over your valve train if you don't need to. However, if you are going to put in heavy valve springs , 7/16ths screw in studs will be in order.
 
Cool. That means, with the additional info gathered from my friend Tom, I'm much better off than I thought. I had the vague recollection there was something I could do to correct it but just couldn't remember. Seeing the tool in the first reply reminded me. They also appear to be .500 11/32 guides. Determining if they're any material other than stock I'm not sure but given the source where these came from, I'm thinking Teflon.

I don't have the rockers or studs so those are not decided. I like the bolt-on option/idea and saving some cash too. Valves has some mushroomed heads so tossed those with the springs and such. Seats are just going to be cleaned. The seats are the question, but it's been a very long time since leaded was available. Hardening the seats might be overkill since this is going to be far from use as a daily driver. If needed, I'll throw a lead substitute in for good measure but I'm already using 93 Sunoco Racing Fuel. Our Phillips Energy location keeps several hundred gallons on hand, in an above ground tank even. No water issues!

Cam is strictly limited to my pulling the engine and doing the refresh. Jury is still out on that. It will be a more stock or slightly milder to what we would have installed in 1978-79 back in High School. The nostalgia side gives me the lope without needing to worry about pistons. I just remember that was the way to let you know there was a much taller than stock cam in that car. Going really any taller than mild is a worry. Remember, these heads are going on a 2v short block, so lift is a concern without the change in lift. There are other variables being considered but I'm not mentioning them in a superstitious sort of way. Then again, not expecting it so maybe more preparing myself for possibilities.
 
Many years ago I had a '64 F100 that I swapped a '72 390 and C6 into (the 292 Y block and T98 went into a '55 Willys 4x4 wagon). When it started running like crap, after 5 or 6 years, I pulled the heads. The valve seats had recessed so much the valves couldn't seat. This engine had never been run hard. Ever since I have had hardened seat installed whenever I had any head work performed. I have a set of Q code heads at a machine shop having guides and seats installed, along with 7/16" studs. I have a set of M code heads that I had seats and guides installed in 20+ years ago that I used the Crane conversion guide plates on and never had any problems with them, never put a lot of miles on them, though. Summit shows them as being not available, so I don't know if you can still get them, or not.
https://www.summitracing.com/int/parts/crn-52655-16
 
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