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Proper Torque procedures RX and Apex Motors

What are you guys doing with head shims?
Splitting the gasket with half on one side half on the other with a gasket spray?? I didn't have much luck with that. I am going with a full gasket on the top and full gasket on the bottom with a smaller head shim to keep the compression the same. I can't decide if I want to use gasket spray this time.........anyone have an opinion???
 

Sapling said:
What are you guys doing with head shims?
Splitting the gasket with half on one side half on the other with a gasket spray?? I didn't have much luck with that. I am going with a full gasket on the top and full gasket on the bottom with a smaller head shim to keep the compression the same. I can't decide if I want to use gasket spray this time.........anyone have an opinion???
Click to expand...

What is your set up exactly.
 
I'm not a proponant of stacking head gaskets, pistons are the BEST choice for lowering compression bar none!!! That being said I think that MIGHT be a low cost alternative, that is a shim between to stock head gaskets. I have never tried that don't know if that wil give good results but I think it's better than just stacking head gaskets.
No need to coat the gaskets, they are already coated that black color is a coating. Clean the mating surfaces with good parts cleaner, no oil, and assemble Good luck with that let us know how it works. :flag:
 
I am not stacking gaskets. I am using a head shim. I'm running a Powderlites turbo on an 07 Apex. I installed the head shim using one factory gasket that I split and installed one half on the top of the head shim and one half on the bottom of the head shim. I used Hi tack gasket spray on all surfaces and torqued to factory specs using the torque plus angle procedure. I have a head shim coming that is 20 thou shorter to allow me to use another full gasket.

I'm running 15-18 lbs on full race at 4000-6000 feet. Turbo is a GT2860RS that Dave ported the wastegate on. I have the double down pipe.

Not sure why it went but the last ride out I ended up with all of my coolant in the overflow and in a catch tank I had put on the drain tube by the chain case. I let the sled cool and checked the coolant the next day and it was still in the overflow bottle and when I removed the cap on the resevoir it was under pressure.

Depending on what I find when I open it up I would prefer to just clean it up and reinstall it using the above torque specs with the head shim and gaskets like I described. I can't decide on the gasket spray. Wet or dry........?????? That is the question of the day..... Normally I would say I always go wet........ ;)!

Hoping to get back on the snow next week.
 
I said I thought you might have a better way with the shim in the middle of 2 stock gaskets, rather than just stacking head gaskets. Still think pistons are the best way to go!!!
You should not of had a problem with the shim between the 2 gasket layers I've done that many times for the budget racers. You had to detonate it for whatever the reason. Whats "full race". Race gas is not quite that simple, there's hundreds of blends some much better that others and I'm not talking OCTANE.
DON'T re-coat gaskets, if it's black it's coated. If you did that above, you might have the answer yourself. :flag:
 
Sapling said:
I am not stacking gaskets. I am using a head shim. I'm running a Powderlites turbo on an 07 Apex. I installed the head shim using one factory gasket that I split and installed one half on the top of the head shim and one half on the bottom of the head shim. I used Hi tack gasket spray on all surfaces and torqued to factory specs using the torque plus angle procedure. I have a head shim coming that is 20 thou shorter to allow me to use another full gasket.

I'm running 15-18 lbs on full race at 4000-6000 feet. Turbo is a GT2860RS that Dave ported the wastegate on. I have the double down pipe.

Not sure why it went but the last ride out I ended up with all of my coolant in the overflow and in a catch tank I had put on the drain tube by the chain case. I let the sled cool and checked the coolant the next day and it was still in the overflow bottle and when I removed the cap on the resevoir it was under pressure.

Depending on what I find when I open it up I would prefer to just clean it up and reinstall it using the above torque specs with the head shim and gaskets like I described. I can't decide on the gasket spray. Wet or dry........?????? That is the question of the day..... Normally I would say I always go wet........ ;)!

Hoping to get back on the snow next week.
Click to expand...

I would just stack 3 stock gaskets DRY and torque, there will only be .003 thousands difference and it is dead reliable.

Ted.
 
thats what i'm doing on mine, i`m stacking 2 stock gaskets, local guys here have run that setup up to 14psi reliably on pump gas. Ted, thanks for answering me on the sequence. Now you said 43lbs final torque with oil, and 42final with moly. Shoulnd't it be a bigger difference between the 2, thanks alot!
 
turbor said:
thats what i'm doing on mine, i`m stacking 2 stock gaskets, local guys here have run that setup up to 14psi reliably on pump gas. Ted, thanks for answering me on the sequence. Now you said 43lbs final torque with oil, and 42final with moly. Shoulnd't it be a bigger difference between the 2, thanks alot!
Click to expand...

Always Use Moly

Ted.
 
I was using a .064 head shim with one split .020 stock gasket giving me a total shim height of .084. I will now be installing a .40 head shim with two .020 stock gaskets giving me a total shim height of .080.

This is on a mountain sled that sees wide open throttle for HUGE amounts of time. I am running a RB3 and giving it timing advance across the bottom that makes up for a bit of the low compression and I am only pulling half a degree at 15 lbs at 10,000 rpms/up. The RB3 will pull more as the boost increases to a max of 2 degrees out at 18lbs or higher. I have had no knock at all.

Twin, I am running VP c12 at 108 mon. Mostly at 15-16 pounds. I have only hit 18 twice.

I pulled it down last night and it was leaking between the #1 cylinder and the water port that is next to the cam chain slot. It also looked like it might have lifted enough for it to leak out on the front clutch side of the motor. I got it all cleaned up with acetone and she looks good as new. No deto or any other issues. I did have more soft brown deposits on the head than I thought I would with the miles that are on this motor.

I think I had two issues. One I really feel the split gasket doesn't allow for any variances in head or head shim. Two I think that using the stock torque procedure that I did not get even torque on the head. I knew when I responded to this thread earlier in the year that I might have an issue with the torque.
I hope to have the shim today or tomorrow and get it back together.
Starting fully together with plastic and all I had it pulled down to the head in 2 hours five minutes. I took me another 2 hours to get it as clean as a hospital!! The most time spent soaking up the oil in the stud holes!

Thank you for the advise. Sorry for the random thoughts.......
 
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