blown headgasket

[zilla5.9]

Hello everyone. Im new in here but Ive read the discussion forums for some time now. Anway Ive got a 96 2500 auto that Ive been tweaking on since 98. Ive done most of the typical mods and Ive really done It now! In my quest for more power I plumbed propane injection into the motor and cranked it upa bit. Bad thing is I had the bleed orfice on my turbo almost completely blocked off. Im running an hx-40 and It was seeing 45# of boost regularly Boy that propane can really spike that boost . Well my 50# guage had A poor time holding that little needle back! My compression was still 17. 5 At the time and my timming was about 16. 5 Of course my coolant has more synthetic in it than my crankcase does. Ive ordered the . 20 thicker headgasket. The past few months Ive noticed alot of blue smoke from the tailpipe before It blew. It never has done that . Im wondering if my head might have some bad seals or maybe a crack ? Is it worth it to get one of the ported castings from Piers and swap my valve train into it? Some feedback from some seasoned vets of pushing the limits would be greatly appreciated. I really want my baby back on the road Thanks in advance!

 

[HoleshotHolset]

IMHO, if you're going through the trouble/expense of taking the OEM head (or any part for that matter... ) off, you may as well put on an upgrade.

Piers' head drops EGT's in a big way, which will allow you to run more fuel = more power!

It's a bit hard to say what's going on in your situation with what we're working with here.....

As for the smoke - could be the turbo seals... . especially after reading how much boost you've been running.



Hope this helps,

Matt - NOT a seasoned 'Vet. , but I'm still 'spicy'!

 

[cumminsgetme]

Do you have any EGT problems? If you do then now is the time to switch to a ported head. It would probably be a good idea when you have the head off to have it checked for cracks.

 

[zilla5.9]

Hey guys thanks for the replys!!!
Whats really interesting is that Im not seeing much EGT over 900 degrees post turbo (been holding out for better guages before drilling my beloved ATS manifold) Its like Im running out of fuel! which would make sense becuase Im not running anything like trick high RPM springs in my pump or delivery valves yet( again holding out for custom Piers pump). The turbos brand new and still seems real tight as far as seals , although I think I'll uncork the wastegate now ! I think I'll call Piers and see about head though. .
By the way how do I post the signature for my truck??? I see the box for displaying It but not too sure how to fill it in? Thank you for your help and advice I'll try to keep you posted...

 

[MikeR]

zilla,



At the top of this screen you'll see a little gray bar that says "user cp" click on it,then click on "profile". You can then fill in what ever info you want visible to the forum.



BTW, If you're going to run serious power,I'd suggest you move your EGT probe onto the exhaust manifold. After the turbo is too inaccurate.



-Mike

 

[SLang]

zilla, just some observations.



With an HX-40 each pound of boost will drop EGT temp 10F from pre-turbo to post-turbo. So at 50 PSI of boost and 900F post-turbo, the pre-turbo temp is 900+500 = 1400F. That really is a problem. Doing it once is bad enough but if you hit 900F post-turbo day in and day out that will hurt your engine.



With a lot of fueling and propane your cylinder pressure can be out of hand. Thus the blown head gasket. Backing the timing down will help control cylinder pressure. Might be something to look at when you get it back together.

 

[sewman]

I just put a head gasket on my trck a month or so ago & while I had it apart I found & marked TDC & timed it b4 I put the head back on it sure turns over alot easier with the head off.

Have Fun

Bob