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Discussion Starter · #1 ·
My buddys k24/20 has 11.1 wiseco pistons. Occasionally one can expect some "piston slap" while the engine warms up, but even after 3 straight hours driving it still makes that sound. The sound is more or less like a 4 cyl diesel but quieter.

After chatting with the engine builder he thought it was odd. He contacted Wiseco and they said everythings o.k. and that was typical.....

Understand this is "second hand" knowledge, I know what the builder said but I wasnt in on the conversation with Wiseco.

The pistons have some kind of "coating" on them....teflon, perhaps.

Either way this sounds like crap to me :down: ...any thoughts guys?
 

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Ive heard that same info from arias also...

Then had motor actually checked and the sleeves that were installed were slighlty off.. and found pistons also were wrong size...

Ask to see if the installer measured the piston diamter vs. the sleeve bore..

once the head is off you can also see if you can move the pistons very easily like a friggin turntable.
 

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V8KO said:
Occasionally one can expect some "piston slap" while the engine warms up.
That's all i have ever witnessed myself.

Go straight to the source. Contact a Wiseco rep yourselves and see if his story checks out.
 

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Discussion Starter · #5 ·
TeamPacman said:
That is true...
Im glad you rang in Pacman. So its obviously wrong for an engine to sound that way after it warms up. I want to get as many facts straight as I can before I talk with Wiseco...or have to take the head off.

This engine probably has a few thousand miles on it, what kind of damage if any to the cylinder walls could they expect to find? The installer also said that the comp check looked great. I reckon I can run one and check the findings out myself.

Anyone here have prior problems with Wiseco? Are they outstanding in solving customer disputes like this. BTW, my new k24/20 swap (which I havent heard run yet) is supposed to have that exact same sound with zero miles on it.

GUys thanks so much...you to Supafly!
 

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V8KO said:
Im glad you rang in Pacman. So its obviously wrong for an engine to sound that way after it warms up. I want to get as many facts straight as I can before I talk with Wiseco...or have to take the head off.

This engine probably has a few thousand miles on it, what kind of damage if any to the cylinder walls could they expect to find? The installer also said that the comp check looked great. I reckon I can run one and check the findings out myself.

Anyone here have prior problems with Wiseco? Are they outstanding in solving customer disputes like this. BTW, my new k24/20 swap (which I havent heard run yet) is supposed to have that exact same sound with zero miles on it.

GUys thanks so much...you to Supafly!
If the noise goes way after it's warmed up, then you have a pistons problem. I think it's an installation problem...Because we ran Wiseco pistons before and never had any problems...

It can do some damage to the rings not the walls...

Call Wiseco and ask them yourself...

It all comes down to a clearance issue...
 

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Discussion Starter · #7 ·
TeamPacman said:
If the noise goes way after it's warmed up, then you have a pistons problem. I think it's an installation problem...Because we ran Wiseco pistons before and never had any problems...

It can do some damage to the rings not the walls...

Call Wiseco and ask them yourself...

It all comes down to a clearance issue...
Oh, o.k. So I was wrong thinking that the "piston slap" was alright if it went away after warm up. Well thats not the case here...so either way its bad news.

I will contact Wiseco Monday morning and update this post later that evening.

Thanks. :up:
 

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Exactly what Pacman said, you will have to check for piston play, you will have to check your tolerance's, especially because you are running aftermaket pistons, and they arent made out of the same aluminum as stock OEM's they expand with engine heat that is why they slap when the engine is cold, but once they warm up, there should not be any excessive noise, we have used JE, Wiesco, ROSS, CP, ETC, and none of these piston's exhibit those sign's after a few hour's of running, it is best that you take Pacman's advice and re-check all your tolerance's and spec's, because it is better to spend a few hundred dollars now :wink: , than a few Thousand dollar's later :eek:


D
 

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here are afew ways in which this can be the engine builder error or no ones fault at all.

#1 Every cylinder has to be bored to exact matching specs of the particular piston that is going into that cylinder. If you just go and bore every cylinder to exactly say 87mm's then it is possible that you will have a bigger or smaller piston to wall clearance on a particular cylinder vs. the others. Which will cause your problem.

I wonder if your engine builder mated each piston to a cylinder then measured the piston then bored that cylinder for it??? If not he could be making up the BS answer that wiseco supposedly gave him just to cover his own ass!

#2 If Wiseco coated the skirt of the piston in-house like JE does they will then give you the new updated piston to wall specs.

If you got the piston coated after the fact from someone else now you have to take into account the thickness of the piston stock vs. what it measures out at coated.

Also if the coating is a crappy one it can wear away very quickly and or if the Piston to wall clearance is to big then the skirt can have overly to much contact with the cylinder wall and wear away the coating and then cause a even larger cylinder to wall gap then what was already there.

Also you have to take into consideration that when a piston expands under heat that the coating has to expand with it!!! If it doesn't expand at the same rate it will start to flake off.
 

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one of my motors with wiseco 9:1 pistons in it does the same thing. runs fine and compression is good however.
 

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TeamPacman said:
No, that can't happen..

If he did then right way he would of had a blow head gasket..
I have run across two engines, both with Cometic HGs, that didnt have blown HGs (yet), and had a very slight knock. They were also both freash engines. When we pulled the heads the pistons were clipping and very thin strip of the GH. Since both blocks are 84mm we grabbed a factory B20 gasket and compared it to the Cometic. There were very noticeable differences. Lets just say I will never use a Cometic gasket in any more of my engines. Now this was on Bseries engines and not K series. Both engines are fine now with the factory HGs.
 

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Discussion Starter · #14 ·
jtuner77 said:
here are afew ways in which this can be the engine builder error or no ones fault at all.

#1 Every cylinder has to be bored to exact matching specs of the particular piston that is going into that cylinder. If you just go and bore every cylinder to exactly say 87mm's then it is possible that you will have a bigger or smaller piston to wall clearance on a particular cylinder vs. the others. Which will cause your problem.

I wonder if your engine builder mated each piston to a cylinder then measured the piston then bored that cylinder for it??? If not he could be making up the BS answer that wiseco supposedly gave him just to cover his own ass!

#2 If Wiseco coated the skirt of the piston in-house like JE does they will then give you the new updated piston to wall specs.

If you got the piston coated after the fact from someone else now you have to take into account the thickness of the piston stock vs. what it measures out at coated.

Also if the coating is a crappy one it can wear away very quickly and or if the Piston to wall clearance is to big then the skirt can have overly to much contact with the cylinder wall and wear away the coating and then cause a even larger cylinder to wall gap then what was already there.

Also you have to take into consideration that when a piston expands under heat that the coating has to expand with it!!! If it doesn't expand at the same rate it will start to flake off.
Good point-s.

I cannot speak for the installer, Im going to assume that he made all the correct measurements but then again the evidence points towards a bad install...or well a bunch of other things.

I guess whats most disapointing to me is the installer (a friend of mine) insists that there is NOTHING wrong. :wow:

Ever since I was just a little kid I was either at the drags (Pops ran a toplino v-8) or in the garage, and Ive never heard anything like this to be o.k.

As for the coating it came from Wiseco with it on the pistons.

BTW this is something I just remembered...last year when we picked up the car right after the install the "ticking or slapping" was alot louder. You actually raised your voice a little with the hood open to talk to someone right next to you. At that time I let the installer know that it seemed not right and he said to drive it around for awhile and see if it diminishes (s?)

My friend told the installer to keep the car until they resolve the problem and thats when the became addament about there not being a problem to fix.

Well Monday is just around the corner and well hopefully have some updates by then. I may not get back online till Tuesday however...going out of town to see my new paint job on the hatchy!!! :up:

Thanks guys for all your expertise...I was really hoping some of you big dogs would write in, thanks.
 

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H2nr said:
I have run across two engines, both with Cometic HGs, that didnt have blown HGs (yet), and had a very slight knock. They were also both freash engines. When we pulled the heads the pistons were clipping and very thin strip of the GH. Since both blocks are 84mm we grabbed a factory B20 gasket and compared it to the Cometic. There were very noticeable differences. Lets just say I will never use a Cometic gasket in any more of my engines. Now this was on Bseries engines and not K series. Both engines are fine now with the factory HGs.
did you make sure that you got the correct cometic gasket not to mention that you used the b20vtec gasket and not the straight b20 gasket like most guys like to use. keep in mind that cometic specifically makes a lsvtec/b20vtec gasket for such purposes. dont justgrab the gasket that matches the bottom end. just because you can.
 

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importpalace said:
did you make sure that you got the correct cometic gasket not to mention that you used the b20vtec gasket and not the straight b20 gasket like most guys like to use. keep in mind that cometic specifically makes a lsvtec/b20vtec gasket for such purposes. dont justgrab the gasket that matches the bottom end. just because you can.
they were the correct gaskets for the application. I am not new to this, we have been building and racing Hondas for over 7 years now. Maybe they just had a bad run but the gaskets we had were not stamped out as straight or exact as the OEM gaskets and the dowle holes were a few thousands looser than the OEM holes allowing the gasket to move slightly. We are not the only people to run into this with the Cometic HG.
 

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H2nr said:
I have run across two engines, both with Cometic HGs, that didnt have blown HGs (yet), and had a very slight knock. They were also both freash engines. When we pulled the heads the pistons were clipping and very thin strip of the GH. Since both blocks are 84mm we grabbed a factory B20 gasket and compared it to the Cometic. There were very noticeable differences. Lets just say I will never use a Cometic gasket in any more of my engines. Now this was on Bseries engines and not K series. Both engines are fine now with the factory HGs.

Everyone is making good points, but bottom line is, when in Doubt, Pull it out... :wink:


D
 

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Discussion Starter · #20 ·
Hey guys, well I spoke to Wiseco today and he assured me that any piston slapping sounds would never happen. He mentioned that even if the tolerances varied slightly from cylinder to cylinder that it wouldn't happen...he explained that the skirt on the piston is actually machined to reduce noise.

Someone had mentioned earlier about the valve train being the potential source, what and where does one start with that. Pretty much whatever you guys tell me is what I will relay to the installer.

I could make an audio recording of the sound but Im not sure how to post it here. FYI I use imagestation and we-todd as my host.
 
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