Yet another head thread, Need advice |
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Yet another head thread, Need advice |
bbrock |
Nov 11 2017, 06:37 PM
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#1
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
This is related to the AA/HAM head GB but I didn't want to hijack. But that offer means I need to make some decisions sooner than anticipated on my resto. The main question is whether to rework these heads or buy new? My very strong preference is to rework what I have, assuming the castings are good. They have not been cleaned so I was thinking about walnut blasting them myself so I can inspect for cracks before deciding whether to move forward on reworking. Is there any reason I should not blast them myself? Any spots that should be masked or blocked before blasting? Basically, I just want to get to a decision point on whether to rework or buy new. After reading so much about how hard it is getting to find good original castings has me a bit spooked, and if I hit a dead end on reworking, I'd like to do it while the HAM GB is still an option. I also don't know what a basic head rebuild will cost. Anyone have a ballpark estimate? I used to be able to send them out to Cali for a couple hundred bucks, but those days are gone. Here's a short version of the history my engine. It's GA 2.0L engine that I rebuilt the bottom end on in the late 80s, but the project stalled before I got to the heads. My best guess is that the engine had about 110K-120K miles on it when it was split. That's a guess because the odometer quit at about 92K shortly after I bought the car. The engine ran strong when the FI cooperated when it was pulled, so no reason to suspect any major issues. Other than a busted exhaust stud, the heads look good with no broken fins and very little carbon in the combustion chamber. So, overall, I feel these heads are a good candidate for rebuilding but would appreciate any advice or opinions. |
McMark |
Nov 13 2017, 05:06 PM
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#2
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Are there any numbers stamped on the cam? Usually they're stamped where the cam gear bolts on.
If you're that on the fence, I'd recommend: Stock fuel injection WebCam 73 96mm AAPistons Stock heads (back to the crack question) Pretty easy build, great torque, reliable fuel injection. Carbs take some 'babysitting' to keep running right and have no cold-start aid. |
bbrock |
Nov 13 2017, 05:38 PM
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#3
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
Are there any numbers stamped on the cam? Usually they're stamped where the cam gear bolts on. If you're that on the fence, I'd recommend: Stock fuel injection WebCam 73 96mm AAPistons Stock heads (back to the crack question) Pretty easy build, great torque, reliable fuel injection. Carbs take some 'babysitting' to keep running right and have no cold-start aid. I should back up a bit. I rebuilt the bottom end of this engine in 1989 and the case has been buttoned up with CAM inside since then. So I can't access without splitting the case. It already has new (and by now, old stock) 94mm euro spec OEM (Mahle) pistons and jugs. I also bought the Weber 40IDFs back then because my FI was a POS and all the cool kids were going to carbs. Crank and flywheel were machined and engine was balanced, and the bottom end was assembled. Basically, everything was ready to roll except rebuilding the heads. Then the project stalled because life got in the way. Almost 30 years later, I'm picking up where I left off. Obviously, I'd like to avoid splitting the case if I can, but I'd like to avoid blowing up the engine even more. (IMG:style_emoticons/default/beerchug.gif) I'm about half way through a major rustoration but as for the engine, the quickest route to being road-ready would be bolting on rebuilt heads and these carbs and calling it good. My FI was totally unreliable before the tear down so I'd need to spend significant time and $ getting that sorted. Plus, I've spent 30 years dreaming about driving this car with carbs, and would really like to see what they are all about. All that has weighed in to my current plan to continue with the carbed engine and make a decision on FI later after I've spent a winter refurbing parts. But if I really have to split the case and swap a CAM now... that could change things. And I REALLY appreciate you taking the time to offer advice. (IMG:style_emoticons/default/smilie_pokal.gif) |
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