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1G So I tore down the engine.....Opinions needed

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SasaniFab

Proven Member
2,433
782
Dec 1, 2013
Mexico, Connecticut
As some of you may know I'm building a new engine, the motor i pulled was the stock motor with 100k. When the motor was pulled I was on my second composite headgasket. The motor was pushing coolant but not smoking. The block looks amazing, there is no signs of detonation. In fact the Pistons look "new". What do you guys think caused this failure? The gasket is perforated? The crank and cylinders are in amazing shape.
 

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Pushing coolant but not burning it off, as seen as white smoke from the exhaust pipe, is likely caused by either a cracked block / head or warped block / head like mentioned above. Did you happen to do a leak down test prior to disassembly?
 
Just adding a noob question here. If the head or block was cracked wouldn't there be coolant in the oil if there was no smoke? And shouldn't he have a lot of blow by as in pcv valve and catch can or dip stick poping out?also could a compression test find this out? In my experience with that problem there was an small leak in my heater coil. But don't listen to me I'm just a noob.:idontknow:
 
Too much timing. Composite gaskets dont like detonation(which you had a lot of). A mls gasket prob would of held but your pistons wouldnt of. Pistons look new because of the water/meth steam cleaning.
 
I would be checking for broken ring lands too
Thanks for the responses guys, the Pistons are in perfect shape. Ringlands are perfect, plugs are perfect. This headgasket went on significantly lower timing. If detonation caused this wouldn't there be evidence of it on the plugs at least? This was just an experiment as I didn't mill the block or head. The new motor was fully machined and I will be running a oem mls with l19 studs. I kind of wish I never installed the standard arps in the motor, I don't think it's needed. It seems like the combustion gases were passing through that area and blowing small areas of the gasket away.
 
I could be delusional, maybe I am. If I was detonating to the point of roasting my head gasket wouldn't there be signs on the plugs, pistons... valves. Every time I took the car out I checked the plugs and they looked perfect. For running meth I was always running rich, the first headgasket saw the timing. This second headgasket didn't see a lot of timing, peak timing was 16 degrees. I thought that was conservative for spraying meth. I don't claim to be an expert....these are just my observations. Its sad that I had to tear the block apart, it looks new. The bearings are great and the rings looked fantastic.....you can even see the cross hatching on the cylinder walls.I just wouldn't put the motor back in to service without having the deck machined. Its not worth it. I will also never use standard arp again, its a waist of money on a 6bolt. If its not broke, don't fix it. This new motor will be running on the 2g timing map for starters and im going to go from there.
 
My failure looked exactly like that. I went through 5 of them before I found the issue. My head studs were not completely seating. I thought they were because they all stopped at the same point but I was wrong. If you did not run a thread chase (do not use a tap) I would highly recommend that you do. ARP sells one for $60 at summit racing on their website. Cleaning the threads is an absolute must. Here is a list of the things that I have learned to do on HG jobs that are all a must or it will leak.

1. Clean the threads with a thread chase. Be sure to use some WD40 while running it through. Do not force the tap or it will break. Don't ask how I know

2. Make sure you check the block and head surface with feeler gauges and a straight edge. You should always have the head pressure tested and hot tanked. Inspect both the block and head for cracks.
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3. Clean the block surface with brake cleaner and one of the yellow plastic/rubber wheels with an air compressor. Do not use a roloc or a scotchbrite.

4. Install the studs into the block dry. No ARP lube here.

5. Make sure to use ARP ultra-torque on the tops of the studs, nut, and washers.

6. Torque in sequence using the 30-60-90 method. Be sure to use a known good torque wrench. Re-check them after a few heat cycles.

7. Be sure to have a good tune on the car. Be sure to run fairly low timing at peak torque and when the turbo hits.

These are just a few things that some people tend to ignore that helped me get over my headgasket issues. Since I have followed all of these, I have not lost a drop of coolant yet. ARP l19's, felpro composite HG, and an Hx40 at 32psi on E85.
 
I us
My failure looked exactly like that. I went through 5 of them before I found the issue. My head studs were not completely seating. I thought they were because they all stopped at the same point but I was wrong. If you did not run a thread chase (do not use a tap) I would highly recommend that you do. ARP sells one for $60 at summit racing on their website. Cleaning the threads is an absolute must. Here is a list of the things that I have learned to do on HG jobs that are all a must or it will leak.

1. Clean the threads with a thread chase. Be sure to use some WD40 while running it through. Do not force the tap or it will break. Don't ask how I know

2. Make sure you check the block and head surface with feeler gauges and a straight edge. You should always have the head pressure tested and hot tanked. Inspect both the block and head for cracks.
You must be logged in to view this image or video.

3. Clean the block surface with brake cleaner and one of the yellow plastic/rubber wheels with an air compressor. Do not use a roloc or a scotchbrite.

4. Install the studs into the block dry. No ARP lube here.

5. Make sure to use ARP ultra-torque on the tops of the studs, nut, and washers.

6. Torque in sequence using the 30-60-90 method. Be sure to use a known good torque wrench. Re-check them after a few heat cycles.

7. Be sure to have a good tune on the car. Be sure to run fairly low timing at peak torque and when the turbo hits.

These are just a few things that some people tend to ignore that helped me get over my headgasket issues. Since I have followed all of these, I have not lost a drop of coolant yet. ARP l19's, felpro composite HG, and an Hx40 at 32psi on E85.
The ran all of the threads with a thread chase, I think my issue was the head and block needed machining. Like I said it was just an experiment. I would NEVER just throw a head gasket on a motor I was building. I think its essential to have both surfaces machine flat in any case. Even when using a composite gasket. I used lube on both ends of the stud....I think there is a lot of conflicting info on this matter. Some say use lube, some don't, some copper spray some don't. I have heard going over 90 ft lbs can egg the composite gasket and ruin it. The new motor im building is completely machined, im running wiseco hds with turbo tuff rods with a oem mls gasket and the l19s.....
 
If anyone can find a thread chase for me send me the link. The arp thread chase is all sold out until the end of December. All the other ones ive found are not very long. I would like a deep thread chase kit. I cant find one anywere.
 
Just make your own. Use a bolt and cut 4 flutes in it.
 
For people who continue to try and make big power and continue to only torque their cylinder heads to only 90lb/ft are going to continue to experience problems. Torque the head down like a man.
 
For people who continue to try and make big power and continue to only torque their cylinder heads to only 90lb/ft are going to continue to experience problems. Torque the head down like a man.
Don't you risk damaging the head gasket? Also damaging the head studs, stretching them beyond yield. I think the deciding factor has always been surface preparation and proper bolt instAllation. How high are you going on composite gaskets. My head was final torqued to 96 lb ft
 
I'll threw a number out here, I regularly torque standard ARP head studs to 102 - 105 ft lbs on motors that are going to see over 30 psi.. no matter the turbo or fuel used. I'm not sure about others.
 
I have a local guy who has been building these motors for years and warned me not to overtorque composite gaskets. I know there is a lot of conflicting information but he has gone 9s in a colt, omni and talon. Either way I'm straying away from composite and going to mls....
 
105lbs as a minimum up to 120lbs. Depends on the goal. Each motor is torque plated. I have even done stock head bolts to 118lbs before. This motor I just finished was done to 105lbs for a composite gasket.
 
105lbs as a minimum up to 120lbs. Depends on the goal. Each motor is torque plated. I have even done stock head bolts to 118lbs before. This motor I just finished was done to 105lbs for a composite gasket.
Have you ever blow a headgasket, and reassembled the motor and just slapped on a head gasket without machining and didnt have problems?
 
I have personally never blown a head gasket. I have however gone in for repairs in mine and my friends cars and put new gaskets on of all kinds and put them back together without issue. Just finished a valve repair on our mirage and will be installing a new gasket and don't expect issues with it. The head was resurfaced as it was a virgin head my friend insisted on using when the build was new from a Hyundai. It took .005" to clean it up. We did make 900hp with it and a basic Mls gasket without resurfacing it at the beginning. After taking an asswhooping it warped in the middle like they normally do. The motor was torque plated to 110lbs with standard arp's. It will go back together at 110lbs.

Before we figured out how to keep a head gasket in our land speed car we would blow them at the salt flats, take the car to town, swap the gasket out and make more runs the next day. We even did it one year at the Texas Mile. Ran a new best pass later that day.
 
I have been chastised but I torque mine to 110lbs knowing I was going to push the boost higher than 30 pounds on a Cometic MLS, and so far up to 38 psi, I haven't had an issue except a earful from some people saying it should always be factory specs. Well they can do their factory specs and I will keep quiet while I toodle around at 38 psi and no problems. :cool:
 
I have been chastised but I torque mine to 110lbs knowing I was going to push the boost higher than 30 pounds on a Cometic MLS, and so far up to 38 psi, I haven't had an issue except a earful from some people saying it should always be factory specs. Well they can do their factory specs and I will keep quiet while I toodle around at 38 psi and no problems. :cool:
I have been told, on a mls, 110 is ok, im just hearing alot of variances on a composite. I will always take advice from the guys in the trenches doing the work and pushing their cars.
 
Im on a felpro composite L19s @90ft lbs. 850+ awhp @45psi. No issues here and see no need in torquing it any higher. You guys that are over torquing and still having head sealing issues have problems else where. I.E. tune, softened head castings, deck prep....etc
 
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