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DIY rebuild or give it to the pro?

Old 05-30-2016, 05:08 PM
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Default DIY rebuild or give it to the pro?

An engine builder quoted $1500 for the head refresh. I'd have to bring the engine to him already taken apart.
Compression is down, thus the necessity of work.

Or, I can give it the old shot in the dark and try my hand at figuring out what it takes to rebuild the motor (with a little help from my mechanic}

Would it be worth it to DIY?
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Old 05-30-2016, 05:11 PM
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1500 for a head refresh or 1500 for a long block refresh?
around here it's 500-600 for a complete head refresh, so I'd say 1500 is really expensive
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Old 05-30-2016, 05:13 PM
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Originally Posted by 18psi
1500 for a head refresh or 1500 for a long block refresh?
around here it's 500-600 for a complete head refresh, so I'd say 1500 is really expensive
Not quite sure.
Let's say long block...
Would it still be too much?
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Old 05-30-2016, 05:25 PM
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kinda stupid to have a whole discussion when you can't even get the simplest fact straight, wouldn't you say?

how about ask him what exactly his prices are for various services?

then we can actually try to help you. 1500 for a complete long block refresh with parts is dirt cheap
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Old 05-30-2016, 05:35 PM
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I suppose you're right.
I'm only curious, having never rebuilt the head (only swapped one on 4G63), how hard would it be to do a good job on the rebuild?
Or is it the case of "whenever possible, give it to the pro"?
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Old 05-30-2016, 05:48 PM
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I've done a few miata head refreshes, and to me it's totally not worth doing yourself.
Lapping the valves, testing for leaks, swapping the guides, re-shimming (on 99+ heads), measuring lash, cleaning, changing stem seals.

If you want to do it to learn or cause you're dead set on doing it, go for it, otherwise it's not worth it at all.

All of this assumes you want it done properly, not some backyard hack job
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Old 05-30-2016, 06:04 PM
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Thank you.
Exactly what I wanted to know
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Old 06-06-2016, 11:36 AM
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A 13B has like three moving parts (or wait, do you mean a turbo 13B?). Rebuilding a head is about a million times more involved.

A guy who does heads seven days a week is going to do a much quicker and less incompetent job than someone who has never done it before and has none of the tools handy. I concede that it's possible to rebuild a head on your own, but I wouldn't do it, especially if you need any valve seat work done.
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Old 06-06-2016, 12:02 PM
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I am a firm believer that if you want something done right- do it yourself. BUT you must be prepared to learn, spend time, and possibly buy specialized tools to do the job. In the end the cost usually comes out the same. Machining a cylinder head is one thing a backyard mechanic simply cant do though without expensive tools to complete a valve job accurately. Sure you could lap valves but you cant give it a performance cut or change the installed height of the valve.

A long time ago (~1998) I needed a GM 2004r transmission built. I brought it to the *best* performance/race transmission builder in Naples Florida at the time. He agreed to help me rebuild my transmission because I couldn't afford his price. Not physically help, but help with pointers and selling me parts at his cost. When I came to him to order selective washers to adjust lash on certain parts- he said "oh you checked that? I never do..." This was from the BEST transmission guy in town, that had a great reputation for building higher end transmissions!

That taught me to always do things myself, and if not (rare for me) demand up front what you expect to be done, and check to make sure its done the way you want in the end.

I can see machine shops not checking installed valve heights, not checking spring installed heights, etc. Merely just swapping parts to quickly get the job done with just enough quality to last in a regular driver.
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