Need Help on selecting pistons

[lodhammerdin]

Hey guys, I've been out of the loop for a while and have come crawling back looking for some help. I have an 03 cobra (mods in signature) and it has apparently melted a piston.

Here's some back story:

I left the car with my brother and father while I left for Afghanistan figuring they would take care of it. Flash forward to about a month ago, I call my wife and she's telling me something is wrong with my car but I cant get an answer as to what the problem is. I get home, go get the car (trailered there and back to Tucson from El Paso) and start looking at it. Car wasn't leaking oil, started and would run but was smoking slightly out of the right side exhaust pipe. So I do a compression test and I have no compression in my Driver side #3 cylinder. So, about 2 weeks ago, the car gets dropped off at a shop here locally. They get it apart and I go take a look and this is what I find:

Sooooooo yeah... The other 3 pistons on this side are all fine. The other side, I'm assuming is fine because compression numbers were all between 145-150.

So this brings me back to why I'm asking you all for help. I need to get a set of pistons and rings but I don't know where to start. A simple search reveals a scrambled brain. To be honest, I have no idea what I'm looking at. So what should I look for? Can you guys make me some suggestions on where to start or even just what to get? Money for me is a little tight right now so I cant really afford something ridiculously expensive but at the same time, I don't want the cheapest option out there. I know that's a lot to ask for but I'm sure something will meet all the requirements.

I'm all ears guys so let me hear it! If you have any questions, please let me know. Thanks in advance for any and all help

UPDATE 15 Dec, 2016:

Made some phone calls today and spoke to many, MANY people and different places and have decided to go with .020 over weisco pistons and rings. So after all is said and done, I'm so far looking at 4k for parts and labor between the mechanic and machine shop.

UPDATE: 28 Dec, 2016:

Motor came apart and here's a better picture of the piston. He sent me pictures of all 8 but this is the only one that has any type of unusual or abnormal wear, all the others look just fine.

UPDATE 06 Jan, 2017:

So got some bad news today. There's a crack in the head from the seat of an intake valve to the plug hole for the same cylinder that melted the piston. So now I'm waiting to hear back from the machine shop to see if he will be able to repair said crack. So in the meantime, I start looking for a decent used drivers side head.

Also, today I was called and told that the injectors are all good and in working order.

And finally, I got the valve covers back from getting powder coated today. Payed $80 for them both. I also had the "32 valve V8" plate done as well. They look great and match almost perfectly. They are a slight shade brighter than the car paint but I think they will work out just fine. Thinking of getting the blower when I go to drop these off to paint the fins of it. Not to sure yet though.

 

[03 Indy Cobra]

All the info you need in this thread.

http://www.modularfords.com/threads/231649-Off-The-Shelf-(OTS)-Custom-ModMotor-Pistons

 

[lodhammerdin]

All the info you need in this thread.

http://www.modularfords.com/threads/231649-Off-The-Shelf-(OTS)-Custom-ModMotor-Pistons

Thank you for this information. I'm going to spend some time reading and read and reading some more. I should have some updates tomorrow on decisions and whats going to be happening.

Thanks again.

 

[jrgoffin]

To go along with that thread, I was the first customer to buy them. Fantastic to say the least.

http://www.modularfords.com/threads/236857-Aluminator-Gibtec-Build

 

[Livernois Motorsports]

Hey guys, I've been out of the loop for a while and have come crawling back looking for some help. I have an 03 cobra (mods in signature) and it has apparently melted a piston.

Here's some back story:

I left the car with my brother and father while I left for Afghanistan figuring they would take care of it. Flash forward to about a month ago, I call my wife and she's telling me something is wrong with my car but I cant get an answer as to what the problem is. I get home, go get the car (trailered there and back to Tucson from El Paso) and start looking at it. Car wasn't leaking oil, started and would run but was smoking slightly out of the right side exhaust pipe. So I do a compression test and I have no compression in my Driver side #3 cylinder. So, about 2 weeks ago, the car gets dropped off at a shop here locally. They get it apart and I go take a look and this is what I find:

Sooooooo yeah... The other 3 pistons on this side are all fine. The other side, I'm assuming is fine because compression numbers were all between 145-150.

So this brings me back to why I'm asking you all for help. I need to get a set of pistons and rings but I don't know where to start. A simple search reveals a scrambled brain. To be honest, I have no idea what I'm looking at. So what should I look for? Can you guys make me some suggestions on where to start or even just what to get? Money for me is a little tight right now so I cant really afford something ridiculously expensive but at the same time, I don't want the cheapest option out there. I know that's a lot to ask for but I'm sure something will meet all the requirements.

I'm all ears guys so let me hear it! If you have any questions, please let me know. Thanks in advance for any and all help

UPDATE #1: Made some phone calls today and spoke to many, MANY people and different places and have decided to go with.020 over weisco pistons and rings. So after all is said and done, I'm so far looking at 4k for parts and labor between the mechanic and machine shop.

We do not recommend going to a .020" overbore on a supercharged application unless you are doing a o.e. type of rebuild with the factory blower. The liners are already thin in the block (yes even the iron blocks)
Looking at your avatar you have a Whipple on the car.
You can use this failure as an opportunity to upgrade your build
With that piston looking how it does you got some bad/poor fuel or something took a dump like bap, fuel pump driver/pump or clogged injector/rail, maf crapped out...
4K for parts and labor on a d.o.h.c. mod engine?
That definitely doesn't sound right.
You would have circulated debris throughout that engine and everything that touched oil would need to be disassembled, cleaned and inspected at a minimum. If not the bulk of it needing to be replaced/upgraded
There should be 40-50 hours in a proper dohc rebuild at a min. with proper machining and assembly
I don't know what kind of labor rates your seeing locally but it's looking like next to free or someone doesn't know what they are getting into which are red flags.

-main bearings
-rod bearings
-pistons & pins
-rings
-gaskets
-lash adjusters
-oil pump
-head fasteners
-camshaft bolts
-main fasteners
-machine work
-disassemble,clean, seals. lap, ck springs at a min.
-assembly


-R&R
-figure out what failed on the car to cause the failure
-tune
for approx. $4K? that sounds like $15-20K worth of work?
We are happy to help with any questions you have as we have been tinkering with mod engines for a min.

 

[97snakebite]

There are a lot of big power cars with .020 block.... just sayin

Sent from my SM-N920P using Tapatalk

 

[98 Saleen Cobra]

I would call accufab and get a set of their pistons.. They're beast mode. The Gibtec's are nice as well

 

[Livernois Motorsports]

There are a lot of big power cars with .020 block.... just sayin

Sent from my SM-N920P using Tapatalk

We do our best to advise people down a path for long term reliability and success.
We are talking about a hot street car from what I gather here.
What you get away with on a weekend warrior or strip car vs something your going to put miles on get treated differently.
Do you know what a .020" piston looks like from running in a big power engine after time?
Maybe those guys are hardblocked?
The liner turns into a "wet spaghetti noodle" at rpm when they are that thin and ring seal is a tad compromised to say the least.
not arguing what others get away with as my personal luck has never been as good as what others seem to have...
I reiterate we are only trying to guide members to a successful conclusion.
We do not offer any engines in a .020" over as a standard.
If a customer stomps their feet and wants us to build one we do our best to make the end user aware of pros and cons and try to accommodate.

 

[Livernois Motorsports]

I would call accufab and get a set of their pistons.. They're beast mode. The Gibtec's are nice as well

Accufab is a great vendor and has offerings similar to what we have.
Gibby is great people and offers killer stuff but I suspect a forum member conversing about a $4K dohc build is not in the market for a billet piston...

 

[Brutal Metal]

Over 50 hours labor for block machining,balancing and assembly?
Are there 45 minute coffee breaks every hour?

 

[lodhammerdin]

Thanks for all the input guys. To start off, 4k does sound a little low but for what its worth, I know 2 guys here in town that took there cobras there for similar work and they payed around the same.

Livernois Motorsports:
As for going .020 over, what kind of an alternative would you suggest?

98 Saleen Cobra:
I have called accufab and heard great things from other members in the past but sadly, they are a little out of my price range.

The way things in my life are going right now have almost drained my savings and this is going to all but deplete. I know that having this car was not going to be cheap or anything like that, its just times are tough and I'm trying to make some changes as well as fix the car. I'm going to be selling the car after its fixed.
I'm still trying to get a full breakdown of parts, labor, what all is being done before I actually move ahead with anything. I'm not trying to spin some sob-story, just explaining everything and how things are for me right now. Least of all did I expect my family to do this to my car (I still haven't gotten a straight answer as to what happened or how or who was driving it when it happened for that matter)

 

[Livernois Motorsports]

Thanks for all the input guys. To start off, 4k does sound a little low but for what its worth, I know 2 guys here in town that took there cobras there for similar work and they payed around the same.

Livernois Motorsports:
As for going .020 over, what kind of an alternative would you suggest?

98 Saleen Cobra:
I have called accufab and heard great things from other members in the past but sadly, they are a little out of my price range.

The way things in my life are going right now have almost drained my savings and this is going to all but deplete. I know that having this car was not going to be cheap or anything like that, its just times are tough and I'm trying to make some changes as well as fix the car. I'm going to be selling the car after its fixed.
I'm still trying to get a full breakdown of parts, labor, what all is being done before I actually move ahead with anything. I'm not trying to spin some sob-story, just explaining everything and how things are for me right now. Least of all did I expect my family to do this to my car (I still haven't gotten a straight answer as to what happened or how or who was driving it when it happened for that matter)

Well if the block cleans up @.006" or .007" it would leave more liner but then your into a full custom piston which has more cost.
Keep in mind the 03-04 Cobras are 2 bolt iron blocks
The boss block would be a minimal upgrade as long as your sticking south of the 1000 flywheel# It has the same 2 bolt design as the 03/04 Cobra block
then you would gain the big bore and be able to run a less costly design piston vs full custom.
we have our Street Series 298 short blocks rated to 750 flywheel for sale for $4500.00 but with a Whipple on the car I would proh step up to one of our Pro Series 298 pieces rated to 900 flywheel with the iron block for $5500.00

of course we have aluminum versions, Boss versions and Big bore sleeved aluminums

 

[lodhammerdin]

Yeah, see, these are all great options if I had a bunch more cash. I appreciate the feedback and information, I just cant afford that right now.

 

[01yellercobra]

So 15-20k to build his current block or 5000 for one of your pre-built short blocks? Doesn't sound like you're trying to sway him at all.....

OP, depending on your skills and shopping ability you can probably come in close to your budget. I know everyone is suggesting custom pistons, but IMO you'd be ok with something like off the shelf Manleys. I ran Diamonds in my big bore set up, but they were one offs. And after Malcolm's issues with them I probably won't go with them again.

 

[oldmodman]

Gibtech can make your set of pistons to whatever bore size your block will clean up at. If you can get a good surface finish without any boring, just a mild honeing that is the way to go. You want AS MUCH cylinder wall thickness as possible. It's way to easy to make more power with a pulley change than it is to bore or stroke the 4.6 engine block. And the Gibtech piston is FAR SUPERIOR to any similarly priced piston out there. Remember, it is a billet piston designed specifically for the needs of the blown 4.6 Mod Motor.
And they can set up your piston for whatever type of ring you want to run.
A lot of people are starting to run a steel top ring and a total seal 2nd. With a standard tension oil ring. After break-in they are getting under 1% leakdown.
And consider using Total Seals dry cylinder break in treatment for faster and safer break-in of steel rings.
Read all the discussions on pistons over on ModFords. It's well worth it.

 

[Livernois Motorsports]

So 15-20k to build his current block or 5000 for one of your pre-built short blocks? Doesn't sound like you're trying to sway him at all.....

OP, depending on your skills and shopping ability you can probably come in close to your budget. I know everyone is suggesting custom pistons, but IMO you'd be ok with something like off the shelf Manleys. I ran Diamonds in my big bore set up, but they were one offs. And after Malcolm's issues with them I probably won't go with them again.

The intent of the participation on the post was to try to offer solid advise for this member and the forum in general when looking at projects like this.
Mentioning the short blocks was only to show what we have available as pre build packages at a fixed price point. The 15-20K was a spitball/ballpark figure for what the whole project would entail parts,head work, assembly, R&R, tune, fixing what failed.
"Doesn't sound like you're trying to sway him at all....."
We want to sell our products but also want to make sure we can reach out and offer help/advise when we can.

Over 50 hours labor for block machining,balancing and assembly?
Are there 45 minute coffee breaks every hour?

That is to assemble a long block for future reference.
Our guys only get two 10 min coffee brakes a day ;P

 

[Nightmare302]

The wiseco are the most durable off the shelf piston. If you plan to stay with your build and not go "crazy" in the future a .20 over will be just fine. If you can swing the extra ~600 bucks it's worth it to have a custom piston and bore only what needs to be taken out to clean up the cylinder. But, you won't notice a difference if you are 600-700rwhp.

 

[MG0h3]

Man sorry to hear this happened.

Tell the rest of your family that a new engine for your car is cheaper than a funeral for your dad and bro. I would lose my $hit over this.

sent you a pm regarding local shops

 

[lodhammerdin]

Ok, so first I want to say thank you for the solid advise from everyone here. You guys have been such a big help and I really appreciate it.

So, I've talked with the shop owner and the machine shop owner and will be kept in the loop as far as how much ends up having to be taking off. If they can do .020 and stop there, we will. If it has to go to .030, I will be getting a little nervous but will still have to go with it. The machine shop doesn't think It will have to go that far because its seems to be more melted onto the cylinder wall, not gouged, but will have a better idea after the machining.

Better news is, my dad and brother will be ponying up for the pistons so I'm definitely going forged. The guys at wiseco are giving me a solid deal on the pistons and are keeping my order in house till i figure out which ones I need.

Again, thanks for the help and insight guys. I'll keep you guys updated on the work as it goes along.

 

[Weather Man]

Didn't see the root cause of the engine failure mentioned. Definitely need to find out if tune, injector, fuel pump, etc need to be addressed. Good luck with your new motor!