Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by TED, Dec 8, 2002.
Im hoping to get a set of Thorley headers for Christmas, who makes the best header bolt?
Get the locking header bolts from summit A+++++
Or Jegs .
I have them and they are a little tough to get on but they work really good.
I used Stage 8 locking header bolts, a bit pricy but They kick ass /forums/images/graemlins/thumb.gif
one of my friends swears by putiing them im loosley with lots of silicone and then once it dries removing them. essentially gluing them onto the block. i use the ones from summit.
just my .02
I don't use those locking header bolts. Too much gobbledy-gook to mess with. Put on a set of Earl's header seals (forget those junk composite paper gaskets!) and use ARP bolts. ARP's bolts are nice because they have under-sized hexes on their heads, reducing any clearance problems you'll have getting a wrench on them with the header tubes in the way.
I think gaskets are included with the headers form Thorley, are Thorley's gaskets the junk paper kind?
I have Thorleys, though I can't say how good they are since my FOR is going slowly (I actually put oil in the various axles, gearbox, tranny and engine last night).
What I do know is that they come with:
1) A pretty thick gasket (I'm guessing it's some sort of composite material)
2) Header bolts that are long enough to get a good enough hold through the thick gaskets and header material. They are a hex head, but reduced size (7/16) so that there is plenty clearance to get a combination wrench on them. They appear to be a hardened material specifically chosen for the application. I tried to use the ARP bolts that came with my engine overhaul kit but they were too short.
3) Great instructions. One of the most stressed points was that the gasket will hold up well if you stay on top of their bolt tightening procedure. This entails not only retightening after the first fire-up but regular intervals thereafter.
The engine hasn't been fired up, but given the design, parts and instructions, and time on the market, I think the whole package is pretty high quality as it comes out of the box. (I did clean-up some ambitious welds in the exhaust port areas to match the head porting I did).
I had pics on the old picture forum before that got removed and I haven't mustered the energy to re-post. /forums/images/graemlins/mad.gif Also "skyblazer" (on this forum) has a pair that he has been using for some time, you may want to check with him. Steve Chin, is a firm believer in Heddmans...
I should point out that the ARP bolts use a 3/8" hex on their heads. The finish is very good on thes bolts as wel, making getting wrenches on them and starting them in holse easier than with standard header bolts.
FWIW, with the Earl's header seals, I just tighten the bolts, fire the engine and run it for a while, then let it cool, then re-tighten and forget 'em. No need for periodic replacement and the gaskets can be re-used without leaks if you need to pull the headers. Check 'em out at: http://www.holley.com/HiOctn/ProdLine/Products/EPP/EPPPM/HeadSeal.html
Those look good and they have various port sizes(I had to trim mine).
Now I have to decide if I should give mine a go or swap in the Earl's while the body's off... thanks Steve /forums/images/graemlins/confused.gif
Separate names with a comma.