Engine Keep Blowing The Durn Head Gaskets!!!!

[elarm1]

My set up is typical cookie cutter simple, why do I keep blowing my head gaskets??? This will be the second time in the last couple of months. Do you think I should get it retuned? Last time it smoked the gaskets between 3-4 and 6-7 and I think it will be the same case this time.
AFR165 heads
9333 PT1's
306 bottom end
block appears fine
Custom dyno tune
Aeromotive 340 pump
42lb injectors
Autolite Copper plug gap at 28
AFR guage is reading 12.5- 12.9 when in boost
about 12#s of boost
This sucks..... I need a guru, Please discuss

 

[Grn92LX]

You are too lean in boost, richen it up. I have mine dialed in @ around 12.8:1 a/f n/a 11:1 347

 

[mikestang63]

Couple of thoughts

• I think you are maxing out your injectors at 540 flywheel hp - either dial it back or get 60#
  
• I'd richen up the tune tune to 11's A/F
• Maybe time for MLS gaskets
• Have you checked the heads and block for warpage

I run AFR 165's, 60# dekka's, FelPro MLS HG's, and still had my tuner dial it back from 475 to 422 rwhp @ 10# of boost. I'm not racing the car and rather have 50 less hp than need to tear it apart all the time. Dyno #'s are great but I see too many tuners tune the car for the piece of paper. not longevity.

Sorry about the misfortune and hope you get it worked out.

 

[a91what]

I agree, I tuned mine for 12.3 afr at 5psi and 11.9afr at 8psi. 12.3 is the leanest I would go in boost...... ever.


Also what does the timing curve look like? At 12psi you should have 21* total at max most people run as little as 16*

 

[jrichker]

Pull the SPOUT out and that will lock the timing at whatever base setting you have. That will reduce performance some degree, but it wall also reduce combustion temps and pressures.

While you have the heads off, have them checked for flatness and have the engine block cylinder head surfaces checked as well. Spend some $$ on a 24" heavy gauge machinist straight edge and some feeler gauges to check the engine block deck with. If you can slide a .002 gauge between the block deck and the ruler, you need to have the block deck resurfaced.

http://www.amazon.com/s/?ie=UTF8&keywords=machinists+straight+edge&tag=stangnet-20

If you haven't already installed a set of ARP head studs, I highly recommend that you do just that.

 

[elarm1]

I straight edged the block last go around and everything checked out well. Arp studs are in the heads and I had the heads milled as well. One was .006 off and the other was .004 when i had them done a coue of months ago. I really believe that its running lean and needs more petrol. I havent talked to my tuner yet and think I will go else where to get it retuned. I will break it down this weekend and we'll see what pops up

sent from my butt pocket

 

[elarm1]

Couple of thoughts

• I think you are maxing out your injectors at 540 flywheel hp - either dial it back or get 60#
  
• I'd richen up the tune tune to 11's A/F
• Maybe time for MLS gaskets
• Have you checked the heads and block for warpage

I run AFR 165's, 60# dekka's, FelPro MLS HG's, and still had my tuner dial it back from 475 to 422 rwhp @ 10# of boost. I'm not racing the car and rather have 50 less hp than need to tear it apart all the time. Dyno #'s are great but I see too many tuners tune the car for the piece of paper. not longevity.

Sorry about the misfortune and hope you get it worked out.

I'm entertaining and researching these MLS gaskets. What are the drawbacks? Do they prep just like regular head gaskets? Which ones would be right for my application?

 

[mikestang63]

I'm entertaining and researching these MLS gaskets. What are the drawbacks? Do they prep just like regular head gaskets? Which ones would be right for my application?

The RA is different- 50 I believe- and both the deck and head surface need to be extremley straight and clean. I would also spray both sides with copper RTV put a dab of Right STuff in the conrers where the HG meet the intake. I ended up using the Felpro 1133, but know they are only good up to a 4.1 bore. They are .041 thick so you that may throw off your valvetrain adjustment a hair and your compression. Plus they are chearper than the Cometic

http://www.summitracing.com/parts/fel-1133/overview/

 

[elarm1]

Smoked!

The same as last time.... between 3-4 and 6-7. I believe its running lean at high rpms. I will be straight edging the block tonight and I need some more information.
1. 60lb injectors are on my list..... What and where can I get them?
2. Upgrading my valve springs to keep up with my cam. These are what Ed Curtis provided me but I am not sure which is which. Help
http://www.flowtechinduction.com/lunati-lsx-dual-valve-spring-kit-73925k1/
http://www.flowtechinduction.com/lunati-lsx-dual-valve-spring-kit-73925k3/
http://www.flowtechinduction.com/fti-lsx-dual-valve-spring-kit-gen6a-k1/
3. New tune is in order. I hear a guy is pretty good in New Jersey..... @84Ttop Can you help? Got time?

 

[FoxMustangLvr]

Maybe send @TOOLOW91 a PM and he can get you hooked up with Kris?