i'm planning my next foolish car project, and i've got to decide if i'm going to use this engine i have. it's a Navarro-built Rambler six that i bought as a load of parts 7 years ago.

the issue is that block and head are both cut for o-rings. see pics. my question is, is this suitable for durable, long term reliability in a street engine? i have plenty of o-rings for it. i have zero experience with o-ringed engines.

i plan on a mild build, carbureted, normally aspirated, cam undecided (streetable), relatively high revs (this engine was run up to 6200 i believe). turbo would be something for later.

the head is unique, a factory "R & D" casting (R&D part number cast in, not a production item) that has has substantial porting. the block was bored and sleeved, to reduce the 199" displacement to 182" for the car class (67-69 Indy).

Tom,

If that's the engine from his INDY car he told us he used gas filled "O" rings, the ring looks large for an standard copper or stainless steel .040 ring. Does the head have a reciver grove? hard to tell from the pictures? Or is the head for a double ring? If they are gas filled they may be rare, don't lose them.

Anyway seal water and oil with silicone and you should have no problems.

Harry

THATS A PURDY HEAD AND WORTH A BUNCH..... IT WILL NEED HARDENED EXH VALVE SEATS FOR TODAYS GAS THOUGH.

thanks harry. the two o-rings per cylinder are concentric; the diameter of the o-ring circle is 4.1" on the block, and 4.2" on the head. double ringed.

So with Right Stuff etc to seal coolant and oil, o-rings should be good for the long haul?

the rings i have are steel (or stainless). hmm, i just pulled out the box, and i may not have a complete set. looks like what i have is tail-ends of sets of 8. the marked bags are from JABCO. some are large wire ID (.040 by eye), some have rectangular cross section, some are packed round+rectangular, and one is an odd crushable? ring, shaped like a tire ("U" cross section) with another "U" ring inside it.

i have other exotics, solid lifter/adjustable pushrods (stock, hydraulic), cast timing cover for camshaft driven fuel pump, cast stainless turbo manifold. likely won't use that stuff.

oh i forgot -- navarro built *two* rambler six indy engines. i've got the first generation -- single turbo, Delorto carb'd, allegedly 550hp (number varies). the better-known one was twin turbo, 750 hp, mechanical fuel injection. i'm fairly sure i have a 'test mule' engine, that ran at buttonwillow and el mirage for testing.

the twin turbo had a block modified for four-bolt mains (mine's stock, two).

O-ringed blocks or heads will require a copper head gasket, so you'll likely have to have one custom made from one of the gasket companies.

YEA AND THERE HARD TO KEEP FROM SEEPING TOO.

Tom,
Would you post some pictures of the "O" rings, all types.

A normal gas filled ring is filled with powder and becomes a gas when welded, it's hollow inside.

Thanks
Harry

ahh. then i have a set of gas-filled, i think.

OK, i'd assumed all along that all of the parts i got from the Navarro auction were for the rambler motor, but these clearly are not. i'd only eyeballed these before; they are 4.25" ID so dont fit my engine. also, one of them is tagged 1970 (other tags fell off) so that post-dates the navarro rambler(s).

the odd double-U ring. only one of these.


one of the possible gas rings. bagged as a pair, with a close-fit surrounding steel square-section ring.





also have a bunch of square-section rings, an assortment, different thicknesses.

i think at this point i'm going to sell/trade all of the navarro stuff and stick with my new 'specialty', the old 195.6 OHV. it's too exotic for my bankroll to make this go.

Tom,
The U shape may be to encapsulate the gas ring, do any of the U shape also fit the inside dia of the gas ring? Different thickness may be for different crush on the gas ring.

Really neat to see.

Mr.Navarro was always ahead of the curve.

Harry

well just fyi followup, i've decided this stuff isn't for me, and i'm putting it on eBay. even at low open/no reserve no bids yet. search for 'navarro rambler' if you want to see them.

the whole lot will go up. i realize i'm skirting close to hawking wares but i just want this stuff to go somewhere useful, money is a lesser concern.

What if he had a driver with two good feet at Indy. Man, did Barney have an up-hill struggle at Indy or what.