[bpang1234]

Idle question here just trying to get my thoughts in order:

I have been having some problems since a track day back in June. We've pinpointed them to a misfiring Cylinder #6 likely caused by a bad tune from my original tuner (Jannetty has since taken over).

I am going to have the spark checked and Leakdown/Compression tested. If it turns out the Piston needs replacing I am thinking of either having just the one replaced or doing a full set of drop in pistons.

I am ProCharger P1X Stage 2.

Does anyone know the price to have a mechanic change out 1 piston OR the price to do a full set of drop in pistons? I assume just changing #6 will be far cheaper.

[KingLT1]

At least regap the rings if you are only going to replace the one piston which requires removing all 8. That being said, I would do drop in forged if the engine was coming apart. I can't answer you price question directly, by logic tells me the cost between replacing 1 piston and all 8 labor wise would be minimal... Most of the labor will be pulling the engine and tear down.

[S2K+1LE]

Labor won't be too far off for either considering you are doing basically the same amount of work.

But, why would you do that? Why would you NOT go with forged internals at this point?

[laynlo15]

I had the same issue, not a bad tune but 200 runs on this motor and I have number 8 at 85 lbs of compression. I looked at mine with a bore scope and did a compression check but also had number 1 at 150 lbs and 2 others in the 185 range and 4 over 200. Mine still made over 700 rwhp with these issues and ran almost 140 mph on my next to the last pass. You need to see if there is any cylinder wall damage and you will probably have to pull the heads off in the car to figure out what you actually need as we did. Good luck but just replacing one pistons probably not gonna work .

[glenB]

You can do one piston, in chassis, pulling only one, all eight don't need to be pulled.

For balance purposes it's easier to use a factory piston. Chances are greater the problem is the rings or vavles, not the piston. If it's the rings you may as well do all.

[bpang1234]

Originally Posted by glenB

You can do one piston, in chassis, pulling only one, all eight don't need to be pulled.

For balance purposes it's easier to use a factory piston. Chances are greater the problem is the rings or vavles, not the piston. If it's the rings you may as well do all.

That's what I thought...why is it that everyone else thinks you need to pull all 8?

I mean I am dumb enough about all this stuff that I really don't know.

[glenB]

Originally Posted by bpang1234

That's what I thought...why is it that everyone else thinks you need to pull all 8?

I mean I am dumb enough about all this stuff that I really don't know.

Cuz they've never attempted it themselves.

Aside from the obvious, unbolt the cap, push up from the bottom, just as if it was on a stand. It just takes longer and a little more care.

[KingLT1]

I didn't mean you needed to pull all 8 if you are only changing one piston. I meant you should pull all 8 and regap the rings minimum if you are going that far into the motor. I just don't understand the mentality of band-aid fixing a car like this.

[Joshinator99]

Originally Posted by KingLT1

I didn't mean you needed to pull all 8 if you are only changing one piston. I meant you should pull all 8 and regap the rings minimum if you are going that far into the motor. I just don't understand the mentality of band-aid fixing a car like this.

+1. Not only that, but if you have smoked a piston there is a chance the bore now needs attention, which you definitely cannot do in chassis...

[laynlo15]

Pull that plug and look at the piston and cylinder wall with a bore scope. Just to pull the pan and replace one will be a pain in the ass. You still don't know what the other cylinders look like either. It took about 5 hours to get it down to the short block and I still have a couple hours pulling the motor and getting it down to the bare block. What ever you decide to do its labor intensive and if you've not done it, well its a lot of work. Since Ted is actually tuning your car now I think I would have a talk with him on what to do also. I doubt he will say replace just one piston, I could be wrong but he's not a band aid guy for sure.

[Deakins]

You really need to decide if you are going to simply repair the damage and move on or if you want to freshen it up. If it were me, I would take the opportunity to have all the bores finished as appropriate to upgrade to a better piston and ring package. Put a beefier set of I beam rods in it, rebalance the rotator, stud it all together and do an AFM delete with tie bar lifters. Now you know it's gonna fire up, run hard for a long time until you freshen the top end up again.

Now you can look at it as simply repairing the damage if you plan on building or freshening up in a season or 2. That way you dont spend the money right now and get more use out of your current parts. Just my thoughts.

[chross12]

Laynlo 15 you said a mouth full. I love true die hard racers. sounds like my dad. pull that plug out and bore scope it first; but if you have it down to the short block. I would have a hard time not taking it out and bullet proofing it. just saying, but money is the ultimate determining factor in a lot of racing situations. But it's all about having FUN!

[avalonandl]

Originally Posted by laynlo15

Pull that plug and look at the piston and cylinder wall with a bore scope. Just to pull the pan and replace one will be a pain in the ass. You still don't know what the other cylinders look like either. It took about 5 hours to get it down to the short block and I still have a couple hours pulling the motor and getting it down to the bare block. What ever you decide to do its labor intensive and if you've not done it, well its a lot of work. Since Ted is actually tuning your car now I think I would have a talk with him on what to do also. I doubt he will say replace just one piston, I could be wrong but he's not a band aid guy for sure.

This... inspect the cylinder. If you need to pull it, do it right and do the WHOLE enchilada....Pull the motor and 8 new forged pistons

[bpang1234]

What do you all think would be the labor on pulling the whole motor and having new pistons, rings and rods put in? I do not have that skill set nor do I have the free time.

Shoot I was trying to get away somewhat cheap enough to get back on track. But you all have a major point in getting it done right the first time meaning I won't have to pay again for the same work.

Ultimately, once the tests that Ted are complete I will ask him his thoughts...I just wanted some advice while I wait for that.