Gaskets RHS Indy X Heads LA style

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daniel9843

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Hi there, was just wondering if anyone knows of the correct gaskets ie cylinder head to use with the RHS indy heads to suit LA block, i have heard there can be some sealing issues around water gallerys on the head surface area. Also the intake and exhaust dont seem to be a real good fit .. i dont have much resource here in Australia.?
Thanks Daniel
 
I have those heads on a LA 360 as well. I never gave it much thought and they are working well. I don't recall if there was any exhaust gasket overlap, but even if there might be with 340/360 sized gaskets as opposed to 318, they are easy enough to trim. The head gaskets can have different water passage opening, but all have enough to function properly. The LA-X heads don't have a heat crossover, so the middle section configuration of the intake gaskets is irrelevant. As long as it seals the lifter galley from the outside. The Mr. Gasket intake isn't cut out for it anyway and looks like it was made just for that. Most performance applications block off the crossover anyway with thin sheetmetal and or hi-temp silicone.

My choice of gaskets are Mr. Gasket. Head # 3211G, Intake # 5840 and Exhaust # 5939.

You can look up the line on Summit's site for more details if these are part of your limited options. But a good quality, name brand head gasket is important. http://www.summitracing.com/search/...mily/mopar-small-block-la?N=400330+4294949549

Watch the rocker arm geometry. There can be some issues with the contact patch and sweep depending on valve height and which rockers you use. I have beehive springs on mine to eliminate any rocker clearance problems.
 
Yes, I was happy with these heads and they helped my car at least 2 tenths in the 1/4 mile over similarly prepped 308 heads with no other changes. No porting or polishing, OEM valve sizes (slightly bigger with the LA-X) and about 5 cc's smaller chambers on the LA-X. I had Harland Sharp help me get the rockers corrected. The valves I used were Magnum length +.100, but they are no longer available from RHS. But I'm sure that most of the gain was from the superior flow, over the valve and compression differences.
 
that sounds promising, i will just be running the valves that came with the head set as close as possible to 1.650 installed height hopefully i dont run into to many dramas with valve geometry.. Im fairly new to all of this ,will be running a hydraulic voodoo cam hopefully im heading the right way?
 
were these ported la-X or the standard? i know Brian at IMH has a cnc program
 
EL5DEMON340 said:
were these ported la-X or the standard? i know Brian at IMH has a cnc program
Click to expand...

Was that directed to me or Daniel?
My ports were as-cast compared to as-cast 308's, except the chambers were 4-5 cc's different. Around 62 compared to around 66.
 
ok sorry Loco, i am just after a low 12 sec pass with these heads my car weighs around 3500lb just wondering weather im heading in the right direction..
 
I used Cometic's on my current set.

On my previous set I used Felpro 519SD's they have a HD Fire Ring compared to the 1008. Compressed thickness on them are .054 FYI.
 
I just bought a set of RHS heads from Brian at IMM. He advised me to use felpro 521SD gaskets, so that's what I bought.
 
ou812 said:
That's what Mad Dart meant..lol!
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Actually I did use the 519's I snipped the pushrod holes off the gaskets after I torqued the heads! The Pistons on that one were out of the hole .016 or so. At the time that was the only gasket I found Available that would work cause of the .054 compressed thickness. That engine was a bastard in many different ways but it ran like a raped ape! Lol
 
The Mr. Gasket head gasket 3211G is listed as being .040" thick. You will need to factor in your piston deck height to help determine the gasket thickness so you don't lose any more compression than necessary, or end up with more compression than your fuel octane can handle.

At "0" deck, that thickness works well with my .035" deck clearance rule including head gaskets. Also gives just enough piston-to-head clearance for a decent quench. It works out to something around 10.5 if I remember correctly.
 
Mad Dart said:
I used Cometic's on my current set.

On my previous set I used Felpro 519SD's they have a HD Fire Ring compared to the 1008. Compressed thickness on them are .054 FYI.
Click to expand...
i thought the 1008 was the HD one with a .039 crush thickness creating a nice quench gap??
 
EL5DEMON340 said:
i thought the 1008 was the HD one with a .039 crush thickness creating a nice quench gap??
Click to expand...

The "SD" gaskets have the Super Duty - HD fire ring.

Depends on where your Pistons end up as to which compressed thickness gasket you will use. Mine were out of the hole on that engine .016. On that engine the quench pad ended up at .038 cause the compressed thickness on the gaskets are .054
 
Mad Dart said:
Actually I did use the 519's I snipped the pushrod holes off the gaskets after I torqued the heads! The Pistons on that one were out of the hole .016 or so. At the time that was the only gasket I found Available that would work cause of the .054 compressed thickness. That engine was a bastard in many different ways but it ran like a raped ape! Lol
Click to expand...

Smarty pants!
 
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