Piston+rods for gen 2 coyote / block strength

[Jackson1320]

Do you think I’m better off buying a straight edge from summit to check for head/block flatness or just take the heads to a shop to have them check?

I’d love to not have to mill if possible.... I wonder about conflict of interest when asking a machine shop to check if a part needs to be machined haha.
The plan is to keep the motor in the car and just pull the heads so they wouldn only be able to check the heads for flatness but obviously if I buy a straight edge I can check both...
Any thoughts?

A straight edge is all you need and feeler gauges. There’s about a 99% chance you don’t need nothing but a head gasket

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[Jackson1320]

Is that your opinion of just the blocks strength ? Or pistons and rods as well?

At 700 to 800 hp he does not need anything. Check the heads check the block if it is good install new gasket and turn it up because you still have room

 

[Jackson1320]

Do you think I’m better off buying a straight edge from summit to check for head/block flatness or just take the heads to a shop to have them check?

I’d love to not have to mill if possible.... I wonder about conflict of interest when asking a machine shop to check if a part needs to be machined haha.
The plan is to keep the motor in the car and just pull the heads so they wouldn only be able to check the heads for flatness but obviously if I buy a straight edge I can check both...
Any thoughts?

If you know what you are doing and just want to do something pop the pistons out install total seal rings or gap yours a little more and reinstall. But if you do that then you may as well put a new bearings then at that point you may as well do new timing chains and tensioner’s why not head studs do you see the domino effect.
But I would use head studs or at least the upgraded head bolts. But definitely do not use the same head bolts again

 

[Bmaughan]

At 700 to 800 hp he does not need anything. Check the heads check the block if it is good install new gasket and turn it up because you still have room

If you know what you are doing and just want to do something pop the pistons out install total seal rings or gap yours a little more and reinstall. But if you do that then you may as well put a new bearings then at that point you may as well do new timing chains and tensioner’s why not head studs do you see the domino effect.
But I would use head studs or at least the upgraded head bolts. But definitely do not use the same head bolts again

I was planning on going with studs.
so you feel that the pistons/rods can handle my power level? If so.. then I suppose gapping my rings (or new rings)would be a good safety measure.
Do you have any specs on ring gap that would be appropriate for my application?
The car only has 20k miles on it so I would imagine bearings/timing chains are in pretty good shape. The only thing I was thinking about, and maybe you could speak into this... mmr makes a case for the secondary chain tensioners failing when running e85 full time. Not sure about that though...

 

[Chris Barnes]

I just recently blew a head gasket... so while I have the whole thing apart I was thinking about swapping pistons and rods since I’ve heard the pistons are most likely the weakest link.

so the question is what do you all recommend?
My car is Procharged making an estimated 700-750 at the wheels on E85 at about 13lbs.

At that power level, what would be the best value?
Are there any “no balance needed” setups?...
or is that lingo just empty marketing and a balance is always necessary?

Any idea if this power level is pushing it for the stock block? Or is it no sweat?
Man I just don’t want to tear this thing down again haha

thanks for your help!

Curious where you are finding E85 in the Phx area? All I can find is E54.

 

[Cory S]

Find out why you blew a head gasket, before you blow another one. Detonation with knock sensor desensitizing isn't a good thing...

 

[Bmaughan]

Thank you for your help by theway

Find out why you blew a head gasket, before you blow another one. Detonation with knock sensor desensitizing isn't a good thing...

yeah that was my first concern... but after talking with Lund he was 99.99% it wasn’t detonation and said that random leaks can occur and they’ve experienced it before. So I’m hoping it’s that simple... we’ll see

 

[Jackson1320]

I was planning on going with studs.
so you feel that the pistons/rods can handle my power level? If so.. then I suppose gapping my rings (or new rings)would be a good safety measure.
Do you have any specs on ring gap that would be appropriate for my application?
The car only has 20k miles on it so I would imagine bearings/timing chains are in pretty good shape. The only thing I was thinking about, and maybe you could speak into this... mmr makes a case for the secondary chain tensioners failing when running e85 full time. Not sure about that though...

Do you think I’m better off buying a straight edge from summit to check for head/block flatness or just take the heads to a shop to have them check?

I’d love to not have to mill if possible.... I wonder about conflict of interest when asking a machine shop to check if a part needs to be machined haha.
The plan is to keep the motor in the car and just pull the heads so they wouldn only be able to check the heads for flatness but obviously if I buy a straight edge I can check both...
Any thoughts?

I would recommend new aftermarket secondary chains sai li has good ones.
Gt350 primary there only $60-$70.
Boss tensioner I really think that these are a good idea.
MMR secondary tensioner flip kit
Total seal gapless rings would be my first choice. If you are not going to get gapless then just reuse your rings and gap to about the top to 022-.024 and second ring .020-.022 oil ring leave it alone
You’re already going to be there so oil pump gears crank sprocket you should expect this job to take you if it’s your first time a good 10 hours of solid labor

 

[Bmaughan]

I would recommend new aftermarket secondary chains sai li has good ones.
Gt350 primary there only $60-$70.
Boss tensioner I really think that these are a good idea.
MMR secondary tensioner flip kit
Total seal gapless rings would be my first choice. If you are not going to get gapless then just reuse your rings and gap to about the top to 022-.024 and second ring .020-.022 oil ring leave it alone
You’re already going to be there so oil pump gears crank sprocket you should expect this job to take you if it’s your first time a good 10 hours of solid labor

That’s for all the info! Couple questions if you don’t mind...
Why new chains? Could they be that worn after 20k miles?

How did you determine those gap specs?... I’m just curious so I can do my own research as well.

thanks again!

 

[Jackson1320]

That’s for all the info! Couple questions if you don’t mind...
Why new chains? Could they be that worn after 20k miles?

How did you determine those gap specs?... I’m just curious so I can do my own research as well.

thanks again!

Not that the chains are wore out but the secondary chains are a weak link and the gt350 are cheap upgrade for the primary’s.
If you research ring gap you will find that on a boosted engine the top ring gap should be between.006 and .007 x cylinder so .006x3.630 or .007x3.630 so .022-.024 is right in that area. The second ring doesn’t need as much as the top because it is not going to expand as much as the top. Some people run top and second rings at the same gap but it doesn’t need the same
I have built 1 or 2 coyotes

 

[schmeky]

That's a really wide ring end gap, but depends on the amount of boost. Mahle says .005" x bore size = .018".

That's what I'm setting my gen3 engine build at.

 

[Bmaughan]

Not that the chains are wore out but the secondary chains are a weak link and the gt350 are cheap upgrade for the primary’s.
If you research ring gap you will find that on a boosted engine the top ring gap should be between.006 and .007 x cylinder so .006x3.630 or .007x3.630 so .022-.024 is right in that area. The second ring doesn’t need as much as the top because it is not going to expand as much as the top. Some people run top and second rings at the same gap but it doesn’t need the same
I have built 1 or 2 coyotes

I see.. I didn’t know that the secondary chains are a weak link.
I was wondering what benefit does the mmr flip kit provide? I was thinking about getting the mmr secondary guides since I’m on e85 full time but not sure if that’s necessary.

you commented on the opg’s/cs... already did that at least so tearing it down will be at least a bit familiar.
I was planning in just doing all this with the motor in the car since I don’t have a lift and I figured taking the motor out the top would be a PAIN... maybe I’m wrong. Haha

 

[Bmaughan]

That's a really wide ring end gap, but depends on the amount of boost. Mahle says .005" x bore size = .018".

That's what I'm setting my gen3 engine build at.

What kind of boost are you building it for?

 

[Jackson1320]

That's a really wide ring end gap, but depends on the amount of boost. Mahle says .005" x bore size = .018".

That's what I'm setting my gen3 engine build at.

No Mahle says.007 for boost.005 for N/A high performance
This is Mahle Aries and cp pistons recommendations

 

[schmeky]

Street/moderate turbo = .005"

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