Rebuilding a 7.3 IDI Turbo

FrozenMerc

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Mahle offers a set of new head bolts for a much better price then an ARP stud kit, and they will get you to about 95% of the strength of studs.
 
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u2slow

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Just an alternative idea for studs... perhaps there's a higher strength off-the-shelf bolt available. Fastenal, etc.
 

hacked89

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Just an alternative idea for studs... perhaps there's a higher strength off-the-shelf bolt available. Fastenal, etc.
You can use gator studs for the IDI which are under $400. Reviews are mixed, I tested them on the engine in my bronco no issues so far.
 

KansasIDI

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The general rule is 20 PSI without studs. With your Factory set up, you'll be in no danger from too much boost. The bottom ends of these engine are very overbuilt. They can hold up to a lot of power just like they are. The biggest weak link is the N/A rods. Your Turbo rods will hold up to more power than 98+% of us will ever see. I wouldn't worry at all about the bottom end.
No there isn't a cheaper head stud option.
I always thought 15 was the max. That makes me feel better about the 16 my service truck can make, it isn’t studded.

If I ever have to have it that far apart, of course, then it’ll get studded. Doesn’t seem super likely to be any time soon, that truck has very few miles…
 

The_Josh_Bear

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Mahle offers a set of new head bolts for a much better price and than an ARP stud kit, and they will get you to about 95% of the strength of studs.
Are these a better steel than OE head bolts?
You can use gator studs for the IDI which are under $400. Reviews are mixed, I tested them on the engine in my bronco no issues so far.
Wes @ www.classicdieseldesigns.com sells off-brand studs from back when ARP couldn't keep theirs in stock. He doesn't say but I'm sure they are the Gator brand.
 

XOLATEM

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cogitator
Lord...I didn't even know if that was a real word...but it is...dates back to at least 1830....

That is a good word...I am gonna hafta use it from.... time-to-time....

Back to the rebuild topic...I reckon I am going to have to source some of those Gator Studs....

Edit; again...when I look got gator studs...all I get is a bunch of john deere returns...how do I find these studs...?

I learn a lot of good stuff from you guys...


Thanks, Men...

Edit; I asked The Girl if she knew about that word and she said..."Of course.."

I am closer to not needing my encyclopedias...She knows more than I do...
 
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Nero

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Or its a super smart computer in Warhammer

Sorry, nerd in me is leaking out
 

IDIBRONCO

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Lord...I didn't even know if that was a real word...but it is...dates back to at least 1830....

That is a good word...I am gonna hafta use it from.... time-to-time....


Thanks, Man...
You're welcome. Actually it was the best teacher that I had in school who taught me that one and he said "cogitate". I extrapolated and used the "cogitator" version. I wasn't sure if it was a real word or nor. I just used it anyway and, what do you know? The heavy handed computer program that oversees this forum liked it, so I was pretty sure that it was a word.
Or its a super smart computer in Warhammer
Didn't know that one.
 

CalebHa

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Hello everyone, I finally got the motor back from the machine shop and started assembly the other day. I got the motor on the stand and after I started on the pistons I noticed there is a gouge on the deck that goes into the combustion chamber.... This is damage that I guarantee I did not do. The shop I went to had good reviews but when I got the motor back it had a lot of little scrapes and dings/fittings that I will now have to replace.

My question is what do you guys think about what my course of action can be? I know I should probably get the shop to fix their mistake and deck the motor but I don't think there is a high likely hood of getting them to do that. Plus I don't feel like waiting another month for them to work on it. I've heard of people fixing things like this with JB weld or other similar products which I'd prefer to just do that If it would hold up but I am seeing what y'all think.
 

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CalebHa

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I think the machine shop didnt plane the deck. You can still see the old firing ring impression.
They did not. I asked them to do the deck as well when I dropped it off but they told me the deck did not need any work done.
 

Nero

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I've never heard of an outfit never doing deck work upon request, but thats me.
As for the integrity of the fire ring with that mark there, I understand the hesitation before using it. I personally wouldn't, and have condemned blocks for it, but let's see what others say.

I know on the engines I work on, there's a spec for divots on the deck surface, usually its only 0.002" unsure what the spec is for an idi
 

u2slow

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That scratch a tough one to argue fault. It can be a scrape from a prior HG replacement, engine rebuild, or any sort of rough-handling of the block by the shop, or yourself.

Last time I had something machined (albeit heads), 0.005" was considered a minimum cut. I think I would try to use that figure to calculate piston clearance height and resulting CR (also see about available HG thicknesses). If acceptable, I'd prefer to have it machined. You're far enough in it seems dumb to cut corners.
 

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