New head bolts??

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gslender
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New head bolts??

Postby gslender » Fri Feb 08, 2013 1:59 pm

Hi,

About to start the process of rebuilding my B6 engine and was wondering on the opinion around new head bolts?

Ebay sell Durapro kits for under $60, so seems like a good thing to do.......
http://www.ebay.com.au/itm/Mazda-Ford-B ... 076wt_1163

Thoughts?

G
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spikes
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Re: New head bolts??

Postby spikes » Fri Feb 08, 2013 2:00 pm

You can just reuse them, they aren't stretch bolts

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gslender
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Re: New head bolts??

Postby gslender » Fri Feb 08, 2013 3:34 pm

spikes wrote:You can just reuse them, they aren't stretch bolts


Mmmm, the Mazda and Rod's Enthusiast's Shop Manual both don't mention replacing them, so that sounds right.

Interestingly the engineering shop (The Torque Team) strongly recommended it... so I'm unsure, especially if it is only $50 considering the large $$$ spent so far on the rebuild.

????

G
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sailaholic
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Re: New head bolts??

Postby sailaholic » Fri Feb 08, 2013 3:42 pm

I'd believe the engine shop. I put arp studs in mine just to be sure.

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gslender
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Re: New head bolts??

Postby gslender » Fri Feb 08, 2013 4:40 pm

sailaholic wrote:I put arp studs in mine just to be sure.
...and only $170 or so best price from ebay.
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sailaholic
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Re: New head bolts??

Postby sailaholic » Fri Feb 08, 2013 4:56 pm

Yah, I was buying valves as well so pricing was a little better out of the states. Though I think 949 might do them cheaper now.

Wasn't saying you need to use arp, just that I also was told to upgrade. I figured it was just something I didn't have to worry about from that point on. ( vague plans of going really high compression bottom end at a later date)

Same reason I put a genuine head gasket on instead of a cheapie.

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timk
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Re: New head bolts??

Postby timk » Fri Feb 08, 2013 5:02 pm

I had head lifting issues on my supercharged NB, it wasn't getting hot just pressurising the coolant and blowing it out the overflow tank. I replaced the head gasket and used some ARP studs and it was never a problem after that.

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Re: New head bolts??

Postby wozzah1975 » Fri Feb 08, 2013 5:38 pm

gslender wrote:
spikes wrote:You can just reuse them, they aren't stretch bolts


Mmmm, the Mazda and Rod's Enthusiast's Shop Manual both don't mention replacing them, so that sounds right.

Interestingly the engineering shop (The Torque Team) strongly recommended it... so I'm unsure, especially if it is only $50 considering the large $$$ spent so far on the rebuild.

????

G


They don't have to be replaced but they should be. They are a torque/yeild bolt and designed to flex. Given what you are using it for (this is your track car, yes?) I wouldn't take any short cuts with it, get an ARP set. Any of the aftermarket factory replacements are fine for general use, but not for high stress. Under high stress the std type bolts allow the cylinder head to flex and move around, and you will eventually have head gasket problems.

The ARP set is more expensive, but the difference in cost is around the same as a decent head gasket.

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Woz
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gslender
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Re: New head bolts??

Postby gslender » Fri Feb 08, 2013 5:54 pm

wozzah1975 wrote:The ARP set is more expensive, but the difference in cost is around the same as a decent head gasket.


Good point!
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koop21
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Re: New head bolts??

Postby koop21 » Fri Feb 08, 2013 6:27 pm

Has anyone used the durapro head bolts before?? I'm going to be change my head also but don't want to pay for arp head bolts, to expensive for my application.



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Re: New head bolts??

Postby NitroDann » Fri Feb 08, 2013 7:00 pm

Durapro is a common brand for lots of engine rebuild parts. Ive used it, not sure how it would rate for a 400% stock power build etc

Dann
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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: New head bolts??

Postby gslender » Fri Feb 08, 2013 7:30 pm

NitroDann wrote:Durapro is a common brand for lots of engine rebuild parts. Ive used it, not sure how it would rate for a 400% stock power build etc

Dann


400% !? Of what? Not power or torque, as I'd like to hear how that's done!

G
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Re: New head bolts??

Postby NitroDann » Fri Feb 08, 2013 8:38 pm

A stock na6 makes like 80 atw and there are plenty that make 320rwhp.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: New head bolts??

Postby project.r.racing » Fri Feb 08, 2013 10:11 pm

what makes a good head gasket? I've seen BP ones from $20 to $200, normal to cosmetic? How do I spot a good one?

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Re: New head bolts??

Postby NitroDann » Fri Feb 08, 2013 10:31 pm

use OEM, they never fail even at 400whp.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.


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