blower experts needed: blown HG on my kb'd 5.0

[BOWTIEKILLR]

the car is an 85 gt with a kenne bell and its headgasket is definitely blown and now i need to figure out what to do next. it was running 5-7psi, then my dad and i switched it to 9-11psi, then back to 5-7 because we noticed alot of pinging with the 9-11, and then realized it was blown after switching it back. we are not sure wether it was the extra boost that blew it, or that it was blown for quite some time and we never really noticed(realitively new-to-us car that sat alot with previous owner and when we got the car one plug wire was completely burnt apart by header). should we just get a nice headgasket, run the 5-7psi, slap it together and call it a day? i would love to run it at 9-11psi but am afraid that it will blow agaian. can i safely run 9-11 psi? do i need to o-ring the heads? i know the motor has about 30k on a 89 block, the original kenne bell, ported gt40 heads, msd ignition, boost-a-pump, bigger injectors (they are black, im not sure what # they are), mass-air conversion with stock ecciv, and some other things i might be forgetting or dont know about. i wish i knew more about the motor but ill try to answer everything i can. thanks in advance

 

[Roland69]

you should be able to change the HG's with some good ones and run the 9-11 pully.

 

[feifong]

where do u buy a supercharger for kb'd?

 

[BOWTIEKILLR]

huh? im not exactally sure what you are asking....

 

[Daggar]

Change the head gaskets. Get some quality FELPRO gaskets. You don't need any fad gaskets or o-ringed surfaces or any of that stuff. Just quality head gaskets.

The boost you were running is not what blew those gaskets. Your TUNE or rather the lack thereof is what blew them. You can't just sit around swapping pullied out then taking the car out for a spin. You created a lean condition, the car pinged, you blew the gasket out, end of story. You're damned lucky that Kenne Bell didn't take a piston or rod out for you.

Once you get the car back together, take it to a reputable dyno tuner and see what's going on with the thing. If you're running after market injectors, then it's also likely that you're running a custom tune. Check the back of the EEC to see if there's a chip in there. If there is, great! It'll save you lots of money on your next tune.

If you want to run more boost, you're going to have to tune for it. That means strapping to a dyno with AFR readings while a custom tune is burned to chip for you or installing an AFR meter of your own and a TwEECer or PMS and street tuning it on your own.

Once again... you cannot just swap boost pulleys around with no regard to tune. PARTICULARLY on positive displacement superchargers. Even if the EEC was somehow able to accommodate the additional boost, it's not able to make those adaptations quickly enough for a PD blower.

 

[just4bob50]

I agree with what Daggar said, and if it wasnt a problem with the tune it you could have been lifting your heads under boost. That is what happen to me. 3 water jackets were blown on each gasket from the port to the fire ring.

 

[Treachery]

- more F-U-E-L!!! <- can't stress this enough! Bigger injectors, fuel pump, etc.

- Custom Tune (chip) <- absolutely mandatory!

- O-ringed heads <- not really necessary but nice to have. There are good points and bad points regarding o-ringed heads.

- Head Gaskets <- Ford Graphite gaskets (for superchargers) work well for non-O-ringed heads. Forgot the part number but they are made to withstand the added pressure/boost that superchargers produce. They are same as Fel-Pro, i believe, but i'd get the Ford branded gaskets for voodoo reasons.

 

[Daggar]

... i'd get the Ford branded gaskets for voodoo reasons.

LOL... I like that. I'll have to remember that line.

 

[BOWTIEKILLR]

damn...i have been trying really hard to get my dad to get it dyno tuned but hes so stubborn. he says that if it still runs good then why mess with it. this is his first blower car and im trying to get him to understand the necessity of chip + tune. ill just get some nice gaskets, put the 9-11 pulley on then get it dyno tuned at apex motorsports. thanks for the help guys

 

[bluevenom867]

damn...i have been trying really hard to get my dad to get it dyno tuned but hes so stubborn. he says that if it still runs good then why mess with it. this is his first blower car and im trying to get him to understand the necessity of chip + tune. ill just get some nice gaskets, put the 9-11 pulley on then get it dyno tuned at apex motorsports. thanks for the help guys

Just remind him that with out tune it might cost a ton for a new short block after the KB blows it to piece cause of detonation do to no tune....

Gaskets I like the Cometics,really nice gaskets,a little pricey but their worth it cause they will probably be the only HG youll need.You can reuse them even after hard use,just give them a coating of copper gasket spray.

But they wont work if you got ruff deck and head surfaces,if thats the case stay with the fel-pros.

 

[BOWTIEKILLR]

its not that hes dumb or anything, he just says if its not broke dont mess with it. i kept telling him he should get a tune from the second he bought it, the he did the pulley and here he is with the blown hg. damn kids are smart these days so im thinking either the ford graphite/fel pro gaskets or the cometics....whichever i can find easier. and as for anything else needed to run the 9-11lbs the dyno tune will tell us whats up.

 

[Daggar]

Just remind him that with out tune it might cost a ton for a new short block after the KB blows it to piece cause of detonation do to no tune....

Gaskets I like the Cometics,really nice gaskets,a little pricey but their worth it cause they will probably be the only HG youll need.You can reuse them even after hard use,just give them a coating of copper gasket spray.

But they wont work if you got ruff deck and head surfaces,if thats the case stay with the fel-pros.

Normally I knod my head in total agrement with bluevenom like his pet chimp however....

I think that Cometic gaskets are the LAST set of gaskets you should ever use in your particular circumstance.

1. Special/additional prep work is required on both the deck and head surfaces in order to install these gaskets.

2. If the tune is even slightly out of whack and detonation occurs, those cometic gaskets are not going to give! They'll stay intact and will handle the punishment. Why is that bad? Because it's your internal eninge parts that are the next weakest link. Those parts are what will take the ass-whoopin and break as opposed to just blowing a head gasket.

Steer clear of cometics unless you're absolutely certain that the tune is perfect.

 

[dragnazz5.0]

damn...i have been trying really hard to get my dad to get it dyno tuned but hes so stubborn. he says that if it still runs good then why mess with it. this is his first blower car and im trying to get him to understand the necessity of chip + tune. ill just get some nice gaskets, put the 9-11 pulley on then get it dyno tuned at apex motorsports. thanks for the help guys

apex motorsports? where are you from? hopefully not apex north carolina

 

[bluevenom867]

Normally I knod my head in total agrement with bluevenom like his pet chimp however....

I think that Cometic gaskets are the LAST set of gaskets you should ever use in your particular circumstance.

1. Special/additional prep work is required on both the deck and head surfaces in order to install these gaskets.

2. If the tune is even slightly out of whack and detonation occurs, those cometic gaskets are not going to give! They'll stay intact and will handle the punishment. Why is that bad? Because it's your internal eninge parts that are the next weakest link. Those parts are what will take the ass-whoopin and break as opposed to just blowing a head gasket.

Steer clear of cometics unless you're absolutely certain that the tune is perfect.

Actualy Dag,as long as your deck surface is smooth and not all gouged up,there isnt any additional prep work.Just remove the old gasket and clean the surface with acetone or mineral spirts.You dont even have to retorque them,but i like to break the bolts loose 90* and torque them again just to be sure I got the proper torque (use the ARP moly lube).

You bring up a good point about the detonation,but really,mild detonation aint gonna hurt the shortblock.The tune doesnt have to be perfect either,just start out on the rich side and lean it out to get power,the other way is how you get into trouble fast (starting lean on a tune).

I dont mind the fel-pro its just after the first pair we used burned through the #3 and#4 fire rings on a 150hp shot on a mild 357 with rich tune up,just didnt really impress me with their strength.

 

[Daggar]

I'll split the difference with ya and say that detonation sufficient enough to blow out a set of felpros is sufficient enough to cause internal damage with a gasket that doesn't blow.

 

[88Stang331]

I'll split the difference with ya and say that detonation sufficient enough to blow out a set of felpros is sufficient enough to cause internal damage with a gasket that doesn't blow.

+1 like he said earlier, if the HG doesn't blow, something else will.