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snapped cam-belt, help needed with head, block and turbo!
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Fasteddie313  



Joined: 29 Sep 2013
Posts: 1418
Location: Not Detriot - NMI

PostPosted: Mon May 25, 2015 5:15 am    Post subject: Reply with quote

What sort of turbo-manifold gaskets are you dealing with? There are 3 variations afaik...
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Josh931  



Joined: 03 Oct 2014
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Location: South Africa

PostPosted: Mon May 25, 2015 7:58 am    Post subject: Reply with quote

Sorry I don't understand the question? I basically need every single gasket for the engine. Non have been salvageable.
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Fasteddie313  



Joined: 29 Sep 2013
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Location: Not Detriot - NMI

PostPosted: Mon May 25, 2015 8:12 am    Post subject: Reply with quote

Between the turbo and exhaust manifold...

Do you have a flat gasket or an aluminum ring?

1st variation had a flat gasket, 2nd has an aluminum ring, 3rd has an aluminum ring and a sleeve sticking out of the manifold that goes into the turbine housing a bit. The ring will stay on the turbine housing when you take it off if it has one (probably). Its either ring or flat gasket, never both.

It being an 80 I suppose it could have any variation, mine is an 80 but US market, has the latest variation, I reused the ring but flipped it over, no leaks.. The rings are about $15 ea here iirc..
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Fasteddie313  



Joined: 29 Sep 2013
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Location: Not Detriot - NMI

PostPosted: Mon May 25, 2015 8:23 am    Post subject: Reply with quote

Josh931 wrote:
need to source new rings and if possible new main bearings. Any alternative rings that work on my car??

I've come across some stuff about machining 931 pistons ring lands wider to accept 924 N/A rings that are superior and much easier to get..

Could someone please give me an idea of how to measure up the spacer I'll need? I have no idea how much the head has been skimmed previously, so how would I determine what the stock dimensions were?

http://www.924board.org/viewtopic.php?t=37743



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Josh931  



Joined: 03 Oct 2014
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Location: South Africa

PostPosted: Mon May 25, 2015 8:24 am    Post subject: Reply with quote

I was pretty certain I had a ring and a gasket, but I'll have to check in the morning, will ask the place working on my turbo if they have any of them as you say theyre not as uncommon as I thought the part might be! That's good news! But then the square gasket that goes onto the exhaust from the turbo and then the j- pipe gasket I think I might struggle a bit with these, but tomorrow I'm going past the guy that supplies the parts for these cars, so I'll have to see what he's got and possibly go past a few exhaust places.

Any ideas for new rings and main bearings?
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Fasteddie313  



Joined: 29 Sep 2013
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PostPosted: Mon May 25, 2015 8:32 am    Post subject: Reply with quote

ebsracingtroy wrote:
hello all
we currently have 924 main bearings in stock now STD and .25 sizes

thank you
troy@ebsracing.com

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Josh931  



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PostPosted: Mon May 25, 2015 4:55 pm    Post subject: Reply with quote

Awesome!! So thankful for all the info! Sorry I should have used the search button for that one, I apologise!

Eddie if you have fiddled around with turbos a decent bit and I know Morghen is pushing around 1 to 1.1 bar, would you go the ARP head stud route? I know a lot of people of this board use them, and there's enough discuss why they use them. But are they essential, are the stock high tensile bolts not adequate? Do you two use them? To be honest I'd like to use them but they are pricey, so if it's something I can leave for now I'd be stoked! My goal is 14psi defiantly no more then that, will keep it stock for a while before going up to 14.
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Fasteddie313  



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PostPosted: Tue May 26, 2015 5:07 am    Post subject: Reply with quote

While I went through extreme research and put a turbo together a few times (because I can't afford to just give it to a shop and hope it comes in as quoted), I have not yet tackled an engine rebuild on one of these cars..

There are a lot more members here that know a lot more about 924 specific engine building than I do..

I have read thousands of pages here on 924board and I can throw links at you but I haven't been there done that on any 924 so any advice I can offer you in that department is only as good as hearsay..
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Josh931  



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PostPosted: Sun May 31, 2015 2:53 am    Post subject: Reply with quote

Just a thought for lowering compression back to standard, has anyone tried skimming the skirts of the pistons slightly?
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Josh931  



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PostPosted: Sun May 31, 2015 2:55 am    Post subject: Reply with quote

Sorry not the skirts, I meant the top edge of the pistons, as they have a fair amount of meat there
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morghen  



Joined: 21 Jan 2005
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PostPosted: Sun May 31, 2015 6:36 am    Post subject: Reply with quote

Just dial a tad less advance..dont machine the pistons ffs.
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Josh931  



Joined: 03 Oct 2014
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PostPosted: Sun May 31, 2015 7:10 am    Post subject: Reply with quote

Haha!! Possible not the best idea to mill the pistons. Less advance or even lowering boost levels to compensate for higher cr isn't to desired as I'd like to be gaining some performance and not loosing it. Will see when the head is done if they skimmed it again, if not then I can just get the same thickness head gasket. Surely these heads get skimmed often as a result of some of them strugging with overheating? What do people do to correct for the skim?

My new stainless steel valves have been machined. They look insane!! Still haven't diagnosed why the belt snapped. Thought maybe I'd dropped a valve as the belt shread itself which seams to be most likely due to the cam gear becoming jammed while the crank was still turning shreading the belt. Cambelt tensioner still seams good.

Organized rings locally, if I can't source mains I'll get the through EBS, gasket sets have been ordered. Turbo will hopefully be done this week. The head should also be done this week, then will drop the block off for a honing.
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Fasteddie313  



Joined: 29 Sep 2013
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PostPosted: Sun May 31, 2015 10:55 am    Post subject: Reply with quote

Josh931 wrote:


My new stainless steel valves have been machined. They look insane!!


Pics or it didn't happen...

What'd ya figure out with the turbo situation? just curious..
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Josh931  



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PostPosted: Sun May 31, 2015 5:32 pm    Post subject: Reply with quote

[img][/img]

[/img][/img]

[img][/img]

[img] [/img]

I was able to find the majority of the parts I needed on eBay for less then I was quoted, so took those prices to the guys rebuilding the unit for me, so they took off the massive markup they had put on the parts I'd needed for the turbo. So I've gone with the standard unit[/img]
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Josh931  



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PostPosted: Sun Jun 07, 2015 7:38 pm    Post subject: Reply with quote

Slowly going through the car. been polishing the corroded cooling system components, trying to match cooling system hoses ect.

The head will hopefully be done soon. Gasket sets have arrived, pistons have been polished, sourced some rings locally. Required matching two different sets. Managed to get a set of big-end bearings, just not mains. Might order the mains from Troy at EBS.

Turbo is finished, looks beautiful! New wastegate adapters have been made, will go with a screamer pipe untill I have time to make an adapter that plumbs back into the exhaust system.

[img] [/img]

[img][/img]

Are these little indents possible signs of slight detonation over the years?
[img][/img]


[img][/img]
[/img]
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