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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

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

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

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

sailaholic wrote:I put arp studs in mine just to be sure.

...and only $170 or so best price from ebay.

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.

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.

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.

Cheers
Woz

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

Good point!

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.



Sent from my potato.

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

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

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

Dann

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?

use OEM, they never fail even at 400whp.

Dann