Ya, if you do not lke the 3.55's you can always swap them out. Good luck Norval.

 

that is the whole point against O rings. This weeping messes up the engine compartment and undercarriage. My car has to run for thousands of miles and I can't have any weeping, none.
My last motor weeped a little and it bugged me.

 

If you look at the head bolt pattern on the BB's, you notice 4 cylinders, 2 on each side, already have 6 bolts completely "surrounding" them. The other 2 "need" those inner mounting bolts in for the gaskets to do their job effectively. Not certain I would trust those "allen" bolts in there, much prefer some ARP studs,washers, and their 12 point "AN" nuts. This is all we use on this style build.

If you've got your block setup for "O" rings you may want to swap over to Corteco's new copper head gaskets WITH the entire piece pre-sealed. We have them on 1200/1400 HP units where we usually used the "dead-soft" copper and install our own sealer. No more leaks OR "blow-outs". They are available in assorted thicknesses and bore sizes for the BB's. Thanks, Gary in N.Y.

P.S. These gaskets are under the heads of a number of units we now build along with many of the "high-end" racers in the country, all with excellent results. One of our own at 7.40's & 180 MPH has a pair on for 2 seasons now. There's a pair on this all-aluminum blown "Keith Black" pictured below!

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just wondering, how well (or poorly) do the extra bolts holes in the block, and in the heads, line up with the extra bolt holes in the GM or FelPro gaskets?

did the holes in the block line up with extra holes in the gaskets in the first place? since you probably don't have an original ZL1 block laying around (I don't either), and unless you have the original GM heads with the extra bolt holes, not sure how to establish which one is the reference standard.

 

The Fel Pro head gasket lined up perfectly with the bosses on the Merlin block. The center drilling on the Brodix heads was off. I adjusted the holes in the head to match the block so I don't know if my taped holes are right for another block?
But again the block lined up perfectly with the gasket. If I had drilled the holes where Brodix meant I would have been off and the head bolts would not have worked.

 

The block is NOT set up for O rings. My last block was. I actually had a complaint from the buyer when he saw the O ringed block. He doesn't like O rings and that means alot of machening to deck the block to get rid of them.
As for the allen bolts they are grade 8 and torqued to 55 foot pounds. Well within their limit but studs would have been nice.

 

Hi Norval, to date with our own units at or above 1400 HP, I "O" ring ALL units. I have NO water leaks with the "Corteco's".

Now, as to blocks that have existing "O" ring grooves, we've been experimenting for some time now with a truly correct "cure". I CANNOT remove the grooves in many of the returning units without an entire new build. Don't want to be milling decks down .031"+ to a "new" surface, SO, we came up with our own "fix" as follows:

This is only for using castings that have the existing grooves. It DOES require re-milling, BUT, removing only a minimum amount of material. What you do is install "copper" wire, .041", and literally "pound" it, as much as possible, into the grooves. Once "seated" the block can now be resurfaced to flat and the "copper" becomes the new "base". We've done a number this way to date AND with ALL gaskets on the market. As I said above, the "Corteco's" are a real pleasure to use. I have some issues with the "Cometic's" to date. Not ours, and probably a surface
"finish" issue, no doubt.

I can "sympathize" with you with respect to the cooling system water "spraying" right out from between the block and heads on the high-end" blown units, it use to really annoy us, but I haven't had that one for some years. It was somewhat common however after each 1/4 mile pass.

(Add) The "Corteco's", these are "dead-soft copper" by the way also, MUST be used in conjunction with the "O" ring grooves only. This is what they've told us, but we have not tested this yet, as we groove any BB in the 1000 HP area and above as "standard procedure".

Thanks, Gary in N.Y.

(Add) To Norval and others with the inner head bolt holes, keep in mind we use a high number of these blocks and have put a "kit" together for this sole area. Consists of 4 stud, 4 washers, and 4 AN nuts, ALL ARP components. If anybody needs them you are welcome to contact me with an e-mail. Although your setup "gets-it-done", it much easier to work the studs/washers/nuts deal, you don't need as accurate measurement with respect to the lengths! Again, it keeps it simpler! Also, I don't see any washers on the "Allen" bolts, always better to have a "buffer" between the casting AND the head of the fastener, especially with the "seat-size" on all allen bolts, much like when using head bolts/studs. They all use washers. If they're in place I can't see them from the photos.

P.S. Just another "tip" here on removing the stainless wire. This was a real "headache" for us through the years and after much "studying" realized the "fix" was a really simple one. We drill a 1/16" hole outside the wire, while it's in the groove, about an 1/8" deep, and simply "pick" the wire out. The "stainless" wire acts as guide so you don't drill into the groove itself. We can remove ALL 8 wires in a matter of minutes. We drill them with a 1/4" drill motor and the 1/16" bit. Simple!

 

Thank you Gosfast. That is alot of information. I just wish I had it a few weeks ago. I would have definitely ordered the stud kit. I just didn't know what else to use beside the allen bolts.
I used Fel Pro composite gaskets but if I have any problems I will go back to the solid copper gasket.
Thank you
Norval

 

good job.