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440 Head Gasket Advice

moparmark440

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New to the forum and new to Mopar. Purchased a 74 Charger about a year ago as a father/son project. Built a 440 to a 512 stroker with 440 source components. No racing just street stuff on pump gas but it did get hot a few times while working to get the cooling right. It is a stock 440 block .030 over to 4.350 with TrickFlow 240 heads. Used FelPro 1009 head gaskets (.039) compressed to end up about 10.6:1 compression. Started leaking coolant between cylinder 1/3 and looking for advice on head gasket replacement. Cometic makes a head gasket with 4.380 bore (.040 compressed). Any comments on a head gasket recommendation is appreciated.
 
Welcome. The fact that you indicated the engine got hot a few times could say something about the gasket failure. Check surfaces for warpage first. What bolts are you using ? What did you apply to the threads ? Did you use proper fastening/torque technique during installation ?
 
Plan to check the heads to be sure they are not warped. 440 source head bolds were used and torqued in sequence as recommended. Nothing on the treads. Not finding ARP bolts for TrickFlow heads.
 
Pretty sure you need a minimum of a light cut on both head and block, regardless of what checking the surfaces tells you after a failure like that. Cometec makes expensive gaskets, but there are a range of thicknesses available to help keep compression where you want it.
 
My take is there is a sealing area issue. That 1009 is not known for that issue. You need to look real close to the firing ring on that gasket. Some blocks can allow a slight over hang into the combustion chamber. If there is any evidence of that then there is most likely your failure. I believe there are other gaskets that can offer less overhang. Cometic is not without issues and can have issues of its own.
 
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Use a straight edge and feeler blade to check the block and heads first. There is a tolerance of around 2 thousands.
Check the surface across and from end to end in several places.
 
Lots of builders use these larger bore gaskets to help with cylinder overhang. FelPro 8519PT1
 
1009 gasket fire ring can get into the bore or bore chamfer and burn thru with the 400 and 440 bore sizes, basically a poor choice. i use the 8519's without any issues, there is a marine gasket that will work but i don't know the part number. i've used 1039's on 400 stroker without any problems.
 
Was the blocked decked when you built it or just bored? Cometic need a specific deck and head surface finish to work properly. If you didn't have this finish done, forget about Cometics. For Trick Flow head bolts, call ARP directly - they know their **** and will help you out.
 
Might want to check deck bolt hole thread depth. Found a few '70s blocks that I had to run a bottom tap to get sufficient thread depth in some holes.
 
All guess work until the head comes off & the cause of the problem found...
 
I'm also in the 8519PT camp...no special finish machining needed, zero gasket issues ever up to and just over 600 HP.
Plus....they're not nearly as expensive as some of the others especially the MLS type.
They also state specifically no need for a re-torque, which I've never done with them, but I'm sure that's a subject the internet could turn into a whole other argument..
Plan to check the heads to be sure they are not warped. 440 source head bolds were used and torqued in sequence as recommended. Nothing on the treads. Not finding ARP bolts for TrickFlow heads.
You put the bolts in dry? Oops...lube on the threads and under the washer against the head is SOP when torquing head bolts. And as far you saying "no ARP bolts for the TF" I can't believe they still don't make a set! I coughed up for TF's own bolt kit when I did mine because ARP didn't have a kit for them "yet"...that was two years ago. You could also buy 10 of the longer bolts, which is what's needed there, I just bought all new ones. TF's bolts are (at least they were) USA made in Cleveland.
 
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All guess work until the head comes off & the cause of the problem found...
Appreciate all the comments. Heads are off and burnt between 3/5. I think I said 1/3 before. Also forgot I used ARP lube on the original head bolts from TF which makes me wonder if ARP actually made the head bolts? I guess the 8519 were in there before. I thought 1009 were used. I was thinking the 4.380 from Cometic would be better on the over .030 of 4.350? Just looking for knowledge from the group as this is not my area.
I'm also in the 8519PT camp...no special finish machining needed, zero gasket issues ever up to and just over 600 HP.
Plus....they're not nearly as expensive as some of the others especially the MLS type.
They also state specifically no need for a re-torque, which I've never done with them, but I'm sure that's a subject the internet could turn into a whole other argument..

You put the bolts in dry? Oops...lube on the threads and under the washer against the head is SOP when torquing head bolts. And as far you saying "no ARP bolts for the TF" I can't believe they still don't make a set! I coughed up for TF's own bolt kit when I did mine because ARP didn't have a kit for them "yet"...that was two years ago. You could also buy 10 of the longer bolts, which is what's needed there, I just bought all new ones. TF's bolts are (at least they were) USA made in Cleveland.

Mopar 440 markup.jpg
 
Appreciate all the comments. Heads are off and burnt between 3/5. I think I said 1/3 before. Also forgot I used ARP lube on the original head bolts from TF which makes me wonder if ARP actually made the head bolts? I guess the 8519 were in there before. I thought 1009 were used. I was thinking the 4.380 from Cometic would be better on the over .030 of 4.350? Just looking for knowledge from the group as this is not my area.


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Those gaskets are the cheap stock replacements. It looks like the heads were over torqued. The gaskets are stretched and distorted. The 1009 race gaskets would be a definite upgrade, and the cometics would be the best answer.
What you have there is a very uncommon failure, that I can only attribute to an overtorque condition.
 
Appreciate all the comments. Heads are off and burnt between 3/5. I think I said 1/3 before. Also forgot I used ARP lube on the original head bolts from TF which makes me wonder if ARP actually made the head bolts? I guess the 8519 were in there before. I thought 1009 were used. I was thinking the 4.380 from Cometic would be better on the over .030 of 4.350? Just looking for knowledge from the group as this is not my area.


View attachment 1409798
wow! that's the first time i've ever seen a fel-pro blow like that. usually the 1009 blows between the two inner cylinders; i know i had to weld some heads up. my guess is when the engine got hot it must've "really" got hot. alum expands different than iron so i bet the head lifted. also i always relieve the dowel pin holes in the head to make sure the head doesn't fit tight. i believe alum heads need a little wiggle room to grow when hot. alum isn't as stable as cast iron and i always chase the head bolt holes to try and find an extra thread or two as previously mentioned. you can look at the bottom of the bolts to see if they have bottomed out. a 1039 gasket is a little thicker. also those look like Icon pistons which i'm using in one of my engines with 8519's. i've had no issues, but i don't have any detonation or cooling problems.
 
Explain your logic
They are all-metal. No composition to "decompose ".
There will always be talk about surface finish, but in reality, they are a 3 PC steel shim gasket. With a better sealing surface than the originals.
Just about every BBD at our track uses them with or without deck resurfacing.
I've used them, re used them, and re used them again.
Would have to be a pretty rocky deck surface before I say no.
 
There will always be talk about surface finish, but in reality, they are a 3 PC steel shim gasket. With a better sealing surface than the originals.
Just about every BBD at our track uses them with or without deck resurfacing.
I've used them, re used them, and re used them again.
Would have to be a pretty rocky deck surface before I say no.
And if you talk to Cometic they will STRONGLY advise against using their gaskets without the proper surface finish. Now, considering they have nothing to gain from that I consider it solid advice.
 
And if you talk to Cometic they will STRONGLY advise against using their gaskets without the proper surface finish. Now, considering they have nothing to gain from that I consider it solid advice.
Yes a retail customer disclaimer. For DIY'ers.

Go with what YOU are comfortable using.
 
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