IH8FORD

iTrader: (6)

I want to know who is using what type of head gasket/Bolt or stud combo?I have the heads off of my 383 right now because they lifted and it was pushing compresion into the cooling system. AGAIN! What came off of it was Flat-out head gaskets and ARP bolts. ON motor it is fine .When I spray it with 150 shot I start having Problems. I think I will go with Cometic head gaskets and ARP stud kit . What has everyone had the best luck with. Mainly interested in Head, Compression , engine size and whether or not you are using nitrous.

speed_demon24

iTrader: (6)

You shouldn't be lifting your heads at your power level. Are you sure you're not getting detonation?

Z8'S

iTrader: (6)

Fel-Pro 1074 ARP studs 24+lbs of boost . Never lifted a head.

fordeater

iTrader: (5)

I run felpro 1074's and ARP bolts not studs no problems

IH8FORD

iTrader: (6)

That's what I keep hearing. That lt1's are not known for lifting. I May have had a detonation problem. I was using pump gas 93 and TR55 plugs I am going to switch to TR6's.I mix race fuel naxt time I spray.

IH8FORD

iTrader: (6)

What heads?

Z8'S

iTrader: (6)

I have had them on my LT1/LT4/AFR220/AFR215rr

96capricemgr

iTrader: (1)

Too hot a plug for juice with a motor that makes any NA power. Maybe even go too a Autolite 103. I have found TR6 and 104 to be about right for a high compression NA motor.

What thickness gasket do you have now?
Victor Rienz 5898 a nice .026 like the Mr. Gaskets but these are better packaged and don't peel the coating unwrapping them
Felpro is .039 the good old standby

Cometics are picky about surface finish, ask your machinist what the surface finish on your heads and block are, if he can't answer you may not want to try as they can weep coolant if the surface is too coarse.

I have only used the Mr. Gasket/Victor .026, when I first installed the heads and cam my fuel system was not up to par and it did see some lean detonation, everything took it well.

Use whatever fasteners the engine was honed with, bolts and studs result in different cylinder distortion when the torque plate is bolted down. For ring sealing purposes I would just stay consistent and not switch between the two.

IH8FORD

iTrader: (6)

I think I should just buy some new ARP bolt's then because I am worried the ones I have may be streched.ARP bolt's are what is was TQ plate hone with.

ABA383

iTrader: (1)

I'm N/A only but I use the Felpro .039s and ARP bolts...11.2 compression 383 ported LT1 heads...

--Alan

matt94z

iTrader: (49)

I've used Felpro's and GM's. I did pop a GM gasket though...

gatorhead

iTrader: (4)

I think that is your problem but I also feel it may be coupled with your fuel delivery, maybe not getting enough when it sprays. With a hot plug the cylinder pressures increases dramatically before it fires off. You also have to pay close attention to your gap in the plug.

Only other thing I can think of is what you set your ring gaps to.

JonCR96Z

iTrader: (33)

Whats your piston/deck clearance? And dish/valve relief volume? IH8FORD has 4cc reliefs, and .007 in the hole. Which with the .040 gaskets he had put him at 12.6 SCR and 9.3 DCR with the CC306. Which is a little on the high side. Especially on the gas.

Jon

IH8FORD

iTrader: (6)

On the Dyno the car ran fat. On the 150 shot the gragh started at 12.0 and at 6000 it was 11.2. What Gap would you recommend?

ABA383

iTrader: (1)

I don't know off the top of my head...LPE and Joe Overton worked out the numbers based on what I had...The pistons are JE flat tops, but I don't know what size the reliefs are or how much in the hole they are, sorry...

--Alan

96capricemgr

iTrader: (1)

I do not run nitrous but all my friends and mentors that do say the bottle loves compression and that it is a myth that you need to lower it for the bottle.

I agree that DCR is getting high, but on the otherhand you are saying the hell with quench.

I would try using the same gasket and going colder on the plug.

Another off the wall idea would be go too a thin gasket to improve quench but change the cam timining slightly to bring DCR back down. I have not taken the time to fully understand DCR but I think retarding the cam a little would bring it back down.

IH8FORD

iTrader: (6)

I cant remember for sure but the cam may be advanced.

SincalT/A

iTrader: (16)

If your cam is advanced then that is not going to help the issue.You are deffinatley on the ragged edge of pump gas capabilities.I if i were you this is some steps i would take to prevent some major damage.


1)If you can bring the cam back 0.
2)Run colder plug TR6 .035 gap
3)Bring your quench to about .035.
4)Run at least 100 octane on the bottle.
5)Keep you engine as cool as possible.
6)Run a retard box on the bottle at least -2 degrees

IH8FORD

iTrader: (6)

I have the heads off of the engine now I will pull the timing cover off THURs. and take a look. If it is advanced that is to easy to set it back to 0. So bringing the quinch back down to .035 will help prevent the heads from lifting on nitrous even though i will be raising the compression .

96capricemgr

iTrader: (1)

Nitrous likes compression.
The "impala" .029 gasket might be worth considering if you do want to try and get quench right.
Cometic has a .027 IF the surface finishes are perfect, they have a lot of options actually.
I listed the .026 gasket PN above but I don't know if I would try and pull quench down that far.

You running a dedicated system for enrichment fuel?