Nitrous vs head gaskets

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elitesrock2

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so i'm purchasing a 340 right now that consists of
302/309 duration .654/.655 lift solid roller
x heads ported with stainless ferrara valves
forged rods and crank
customs ross pistons 11.7-1 compression
super victor intake
berry grant 750 cfm carb

now my question is when it was ran on nitrous it kept blowing head gaskets.
is there any way to help with this issue or something possibly doing wrong.
it was hesitating just a hair when we put nitrous to it and popping a little at high rpm
and then the next try it blew
 
I would recommend getting your nitrous tune dialed in. Sounds lean and lean will melt head gaskets. Aside from that I recommend arp stud kit and make sure your surfaces are flat. You didn't mention how much nitrous your were putting to it. O ringing the block is an option as well.
 
340dartley said:
I would recommend getting your nitrous tune dialed in. Sounds lean and lean will melt head gaskets. Aside from that I recommend arp stud kit and make sure your surfaces are flat. You didn't mention how much nitrous your were putting to it. O ringing the block is an option as well.
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Good advice here, Cometic head gaskets hold up well.
 
IMO, someone didn't know what they were doing putting nitrous on a NA engine. You have to build an engine for nitrous. With a static compression ratio that high, that engine was not built for nitrous. I think it will be a miracle getting any head gasket to hold up.
 
try cometics and over torque the head bolts, make sure they a ARP first. O-rings and copper will work great. there is nothing wrong with that compression ratio. you just have to retard the time more. and don't skimp on the gas jet.
 
It should be fine - sounds like the tune on the bottle is off. Too rich is as bad as too lean, and the ignition has to be really consistent and powerful given the higher static and NO2. It's easier to tune a lower static ratio - but it's not a necessity. What did the plugs look like? You should be looking for aluminum transfer to the porcelain to see if it's detonating.
 
Probably should dial in the nitrous tune-up before taking away the pressure vent. Currently the head gaskets are the weak spot that's letting go. If you add studs and serious gaskets/o-rings without sorting out the tune, where's the pressure and heat gonna go? Bye-bye rings, ring lands, rods, upper rod bearings etc. Something else has to take that beating. And all of those things are more money and work than gaskets. Tune then strengthen would be my route.
 
RustyRatRod said:
IMO, someone didn't know what they were doing putting nitrous on a NA engine. You have to build an engine for nitrous. With a static compression ratio that high, that engine was not built for nitrous. I think it will be a miracle getting any head gasket to hold up.
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Just realized I did nothing to actually answer the original question. Need to get some measurable data on the tune. Read the spark plugs, get gauges on fuel pressure, AF would be a great idea.

Also don't discount it being a few problems at once. For instance the early hesitation could be tuning and the pop at the big end may be not enough fuel pump. Double check fuel pump and line size are plenty big for your power level on the juice. Common formula is: For GPH, estimate your total HP then divide by 8. This is based on a BSFC of .50 and includes a 50% safety factor. Shouldn't see a drop in fuel pressure at WOT and nitrous/n2o fuel flowing.

Put the same style gaskets back in it, run to half track and read. Get that perfect, then start going farther and fine tuning until a full clean pull is no problem.
Good Luck!
 
I run SCE copper head gaskets. My heads are O Ringed and I have receiver grooves cut into the block. ARP head studs too. There simply isn't enough clamping force on a SB Mopar with 4 bolts per cylinder with boost and spray. Debate all you want with FelPro 1008's, Cometics, tuning..... Excessive cylinder pressure, excessive RPM's will result in lifting the head and ultimately a head gasket will let go. The ultimate in head gasket sealing is copper gaskets, O Ringed heads with receiver grooves in the deck... This will not fail.
www.scegaskets.com has some great tech under their FAQ.
 
MiradaMegaCab said:
I run SCE copper head gaskets. My heads are O Ringed and I have receiver grooves cut into the block. ARP head studs too. There simply isn't enough clamping force on a SB Mopar with 4 bolts per cylinder with boost and spray. Debate all you want with FelPro 1008's, Cometics, tuning..... Excessive cylinder pressure, excessive RPM's will result in lifting the head and ultimately a head gasket will let go. The ultimate in head gasket sealing is copper gaskets, O Ringed heads with receiver grooves in the deck... This will not fail.
www.scegaskets.com has some great tech under their FAQ.
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I agree o ring copper the best sealing setup, but if the tune isn't pretty dialed in it'll be a bigger disaster than smoked head gaskets. Lots of CR and juice means it's not gonna have much margin for error. I'd sneak up on it, and use weaker head gaskets as a safety valve until the tune is relatively sorted. Nuking the short block a few times figuring it out gets expensive! Even with a good tune the weaker gaskets likely will be a common failure. Once the tune is good, clamp some serious copper gaskets in and rock on. Still havent heard how much N2O he's running? If its a big shot then back it off, tune it work back up.
 
Oh I definitely agree with everyone's advice on the tune. Plenty of good suggestions posted above. A tighter plug gap, cooler spark plugs,non projected tips, full groove main bearings,**** I use a 12" line from fuel solenoid to plate and a longer 18" line from nitrous solenoid to plate. Just so the N20 and fuel hit the engine at the same time. Many tricks to engine longevity but after the tune is dialed in the head gaskets are still the weakest link.
 
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MiradaMegaCab said:
Oh I definitely agree with everyone's advice on the tune. Plenty of good suggestions posted above. A tighter plug gap, cooler spark plugs, full groove main bearings,**** I use a 12" line from fuel solenoid to plate and a longer 18" line from nitrous solenoid to plate. Just so the N20 and fuel hit the engine at the same time. Many tricks to engine longevity but after the tune is dialed in the head gaskets are still the weakest link.
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Yup!
Let us know how it progresses, Elites.
 
What ignition system are you using? What's your timing? How much do you pull out when you start the nitrous? What nitrous and fuel jets? S/F....Ken M
 
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