Fire ring vs. O-ring

Guys, this truck is running the same file that Jason Epling did 860 on fuel at thoroughbred's dyno day and 943 with a little spray. The tuning is there and he seems to have the supporting parts, I am surprised the head has not lifted with just 425s. FWIW, Hunter I would strongly suggest fireringing the head and block with the power that truck is capable of. Did you ever get your rail pressure issue figured out?
 
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Joesixpack said:
Machine the head and the block and then take two cracks at so you can re-torque after every other race just so you can hold what the MLS will already with 625's.

And by me boost is a good measure of potential, correct tune a given. And in that case more boost more cylinder pressure all else equal.
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That is basically 5+ miles of constant WOT and 95+ lbs. of boost before retorqueing it. Probably more WOT running than a street truck would make in 40,000+ mi. ESPECIALLY one that was 900 hp!! I can't even drive my 900+ hp truck on the street for more than a sec. or two at 50% throttle let alone at WOT:poke:


Have you seen what 625's do to the cylinder walls? I have numerous times!! They distort the block tremendously!!

I would NEVER use 625's unless I was having the block bored with a torque plate!!
 
Can't help your tune's so miserable it can't be used on the street.

625's dont distort the block any more then any other fastener at the same clamp load.
 
Joesixpack said:
Can't help your tune's so miserable it can't be used on the street.

625's dont distort the block any more then any other fastener at the same clamp load.
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Bull...Then you have never seen one being bored or honed using a torque plate as compared to 425's!! The cylinder literally becomes an oval and the threads are visible.

And my "tune" is not "miserable" :rolleyes: I'm just a little more responsible than most of you 20 somethings!! :doh:
 
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Well,,, I ran over 1000 HP for almost 2.5 years, at over 80 PSI with ARP2000's no O-Ring or anything. Never lost a head gasket in my life. Only went to O-Ring when I upgraded to an even bigger turbo... my new engine has fire rings and I wish it didnt... I see way too much opportunity for error. If you undersize your head gasket even just a tiny bit, your dead in the water (pardon the pun) A MLS gasket with properly torqued studs and a little care will hold a lot of boost
 
Dockboy said:
Bull...Then you have never seen one being bored or honed using a torque plate as compared to 425's!! The cylinder literally becomes an oval and the threads are visible.

And my "tune" is not "miserable" :rolleyes: I'm just a little more responsible than most of you 20 somethings!! :doh:
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Another waste of time, I've seen the cylinders on multiple engines using 625's at 150lbs and have yet to see any sign of any kind of seaing issue near the stud bosses. Any excessive cylinder deformation would show in crosshatch wear and I've yet to see it.
 
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Well I appreciate the suggestions a bunch. I'm thinking I'll just go up to the 625s, bottom tap to grab a few more threads, and call it good. I think I'll just wait on the rings and if it blows, then we'll cross that bridge when we get there.
 
Greg, I think that you might be thinking that 625's are 14mm,, which is not the case. They are the same 12mm as the others, just a much stronger metal that can be torqed down much harder
 
morkable said:
Greg, I think that you might be thinking that 625's are 14mm,, which is not the case. They are the same 12mm as the others, just a much stronger metal that can be torqed down much harder
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Kevin, I know they are 12mm, not 14mm. I am just letting people know what I have seen with my own eyes at the machine shop
 
Ok, just wanted to make sure that there wasnt a communication failure,, LOL seen it too many times, guys arguing the same point, with 1 major peice of info missing,, LOL
 
Joesixpack said:
Can't help your tune's so miserable it can't be used on the street.

625's dont distort the block any more then any other fastener at the same clamp load.
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Dockboy said:
Bull...Then you have never seen one being bored or honed using a torque plate as compared to 425's!! The cylinder literally becomes an oval and the threads are visible.

And my "tune" is not "miserable" :rolleyes: I'm just a little more responsible than most of you 20 somethings!! :doh:
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Did you skip over the bolded part? Same clamp load is going to provide the same distortion, whether is brass threaded rod or unobtainium super secret stud material.
 
morkable said:
Greg, I think that you might be thinking that 625+'s are 14mm, which is not the case...
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I have a box of those in the shop. They aren't cheap, but they are out there. Those + mls gasket = 9's @ 140mph @ 7000lbs no o-rings or fire rings. *bdh*
 
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