298....tr6060.....67mm@20 psi.....in progress!

[Saleen S281]

Look in his sig where it says built not bought.... lol


On the birght side at least you know the turbo is good since there is no engine oil running through it!

Hopefully you are just an overbore and new set of pistons away from gettign her fixed. 2618 flavor of course.

Yeah, saw that, lol.

 

[05stroker]

Did you see the crank wheel? Anyone make a billet version?

Sorry to see this. I have a MMR unit and lower timing gear for it here if you go that route.

Looks like you my need a sleeve in that cylinder also. I have done that a couple times now.

The damaged crank trigger wheel should show a bank to bank difference in the datalogs if it was the issue though. It is so common on some cams theses days that it could be overlooked.

 

[one eyed willy]

Sorry to see this. I have a MMR unit and lower timing gear for it here if you go that route.

Looks like you my need a sleeve in that cylinder also. I have done that a couple times now.

The damaged crank trigger wheel should show a bank to bank difference in the datalogs if it was the issue though. It is so common on some cams theses days that it could be overlooked.

I was definitely seeing bank to bank a/f difference in the logs. I wasn't sure why, figured I had an exhaust leak somewhere.

There's no deep grooves in the cylinder wall really, I think it looks worse than it really is, most of what you see in the pic is left over piston melted to the wall.....hopefully it can be bored?

 

[05stroker]

I was definitely seeing bank to bank a/f difference in the logs. I wasn't sure why, figured I had an exhaust leak somewhere.

There's no deep grooves in the cylinder wall really, I think it looks worse than it really is, most of what you see in the pic is left over piston melted to the wall.....hopefully it can be bored?

If not a sleeve is a $100 and will hold fine. I have had a few of them. There are two in my block now.

 

[one eyed willy]

Dropping the block off on Thursday morning, they will be doing a bore job with torque plates and cleaning it all up. 3 day turn around. So I should be able to order new pistons next week.

 

[BLKS197]

Subd

 

[tmcolegr]

Dropping the block off on Thursday morning, they will be doing a bore job with torque plates and cleaning it all up. 3 day turn around. So I should be able to order new pistons next week.

How is the machine shop going to accurately hone the block for the proper PTW clearance and surface finish without the pistons & rings?

 

[Clipboard]

How is the machine shop going to accurately hone the block for the proper PTW clearance and surface finish without the pistons & rings?

You can order pistons to match your bore.

 

[one eyed willy]

How is the machine shop going to accurately hone the block for the proper PTW clearance and surface finish without the pistons & rings?

i have to order custom pistons already because of the bad piston messing up the cylinder wall. so once that bore it to get rid of the problem spot, ill know what size to order. when i called livernois they asked me what the bore was and i told them i didnt know what it was going to be yet.

 

[stang67gt]

How is the machine shop going to accurately hone the block for the proper PTW clearance and surface finish without the pistons & rings?

Usually bore to get your planned piston size, then hone to dial in PTW clearance and surface finish depending on the rings he is using.

 

[tmcolegr]

Usually bore to get your planned piston size, then hone to dial in PTW clearance and surface finish depending on the rings he is using.

Really...

thank you for clearing that up for me

 

[recordbreaker5]

nothing wrong with sending your motor off to someone who assembles hi-performance motors daily. I think once you reach a certain level of performance, it should be done by someone who has the education and experience. Gives you that warm and fuzzy feeling.

 

[GTGHOST]

dont feel bad one eyed im in your same boat right now with the motor issue...what boost levels were you going to run? i have the same setup as u 5.0 forged im buying a comp 80mm gonna go for big numbers...had a saleen blower now going turbo

 

[one eyed willy]

16-17 psi when it happened. I do believe its been slowly failing over time, getting worse. Then it just broke finally broke thru finally.

 

[GTGHOST]

its weird that i had the same piston issue but a plug burnt up and piece fell into the cylinder. only one tho. i am hoping to get an 80mm comp turbo on the car and run 20psi for the strip on race gas...see what we can get ourself into lol

 

[one eyed willy]

Tore everything down today so I can get the block to the shop. One of the wrist pin bearings looks shot. The rod connected to the bad piston is shot as well.do they sell wrist pin bearings?

After talking to mod max, they recommended ordering the pistons and then machining the block to match the pistons. So I'll need to run it by the shop and see what they can suggest for bore size.

 

[Turbostangs90]

Wrist pin bearings? Is there such a thing? I thought the wrist pins were pressed in, and they just spin inside the piston. Looks like the clearances may not have been right from the start therefore the pin was spinning somehow inside the rod.

 

[19COBRA93]

Wrist pin bearings? Is there such a thing? I thought the wrist pins were pressed in, and they just spin inside the piston. Looks like the clearances may not have been right from the start therefore the pin was spinning somehow inside the rod.

The pins are floating in these motors, the pin is supposed to spin freely. It is technically a bearing surface.

Your rod end likely looks like that from the overheated piston. It can be fixed, not sure of the process, but they can hone it, or press in a new sleeve and machine/hone it to the proper clearance.

When I put a hole in a CP last year, my piston and cylinder wall looked exactly like yours, and my cylinder ended up being out of round from the heat in that spot. We had to sleeve it to get it back in spec.

For reference, here is a CP out of my car, this is the result of just a little too much timing for the boost I was running and 91 octane:

 

[one eyed willy]

Wrist pin bearings? Is there such a thing? I thought the wrist pins were pressed in, and they just spin inside the piston. Looks like the clearances may not have been right from the start therefore the pin was spinning somehow inside the rod.

See the bronze color and the circle around the edge, it's a bearing that is pressed in.

 

[one eyed willy]

The pins are floating in these motors, the pin is supposed to spin freely. It is technically a bearing surface.

Your rod end likely looks like that from the overheated piston. It can be fixed, not sure of the process, but they can hone it, or press in a new sleeve and machine/hone it to the proper clearance.

When I put a hole in a CP last year, my piston and cylinder wall looked exactly like yours, and my cylinder ended up being out of round from the heat in that spot. We had to sleeve it to get it back in spec.

For reference, here is a CP out of my car, this is the result of just a little too much timing for the boost I was running and 91 octane:

Ouch, that's about how mine looks! I believe I will back out some timing down low, the particular run I was making when it blew was from down low in 4th gear. My timing may have been too high in that low area, creating a ton of heat.