topline 8:1 pistons

[1gjosh]

I am in the process of a rebuild right now, and i was just curious about these pistons. Anyone have them? are they any good? I know they're not wiseco or JE or anything. But does anyone know how much power they can handle? Any info would be great. Thanks

-josh

 

[keltalon]

I have been runing strong for over a year now with itm pistons. I am pushing over 300hp to the wheels. I boke a ringland in a set of topline pistons.


http://www.store.partsdinosaur.com/product90.html

 

[mikyrc]

Then you're not the first one to tell me about broken ring lands on Topline's.

So ITM's are as good as OEM then?

 

[roni-wan]

I am running ITM pistons 18+ psi of boost no problem at all

 

[brute]

Right now I have ~2000 miles on my rebuild with Topline pistons. They are going strong, and I have been happy with the quality thus far. I'm only on 11psi, though. Good luck!

 

[laserspeeddemon]

2g pistions go for about $50 on ebay. Get them hot tanked and checked by a machine shop for intregrity. All in all, you will probably only pay about $100 for a set of good, reconditioned 2g pistons.

 

[mikyrc]

I need to lower the CR as i'm suffering of detonation, so 2G pistons will not be good for me. And also i need .020" overbore as the cyl walls are in bad shape.

 

[C_Keagy]

Motor had over 10,000mi on it laying down 326 on 26 lbs with race gas. they seem fine to me. make sure you have a good tune !

 

[keeler]

I'm running 22psi daily on pump gas with Topline pistons and have had no problems, I'm right around 10k miles

 

[Splitpi]

I need to lower the CR as i'm suffering of detonation, so 2G pistons will not be good for me. And also i need .020" overbore as the cyl walls are in bad shape.

Get a thicker head gasket and or port the head compression bowl to lower your compression.

 

[mikyrc]

Yeah, that would work too, but if i'm going to have to bore the cyls anyways, why not just get lower CR pistons?

It's easier, don't?

 

[mikyrc]

I've finally bought a set of ITM pistons from partsdinosaur.
They're 0.20" overbore 7.8:1 CR for a 6bolt block.
I'm gonna run around 20-22psi on 93 gas and EvoIII turbo. 264/272 cams 720cc injectors,...

I need to know what piston to cyllinder wall clearance and ring gaps should the machine shop leave them at.

Please, Keltalon or anybody can help me on this??
Thanks a lot guys.

 

[TimG]

Call ITM or wait for the packaging as the specs are usually provided. (At least they were with my ROSS pistons). And even when I lost the specs, I called the boys up at ROSS and they told me the clearances I need.

 

[eviltalon1]

I ran Topline pistons on one of my builds and I think they are good for a stock rebuild but not for a performance build. I broke 3 ring lenses probably due to detonation, But not severe detonation, 2 to 3 degrees of knock retard on my Dsmlink at the most. They only lasted about 12000 miles. I would just spend the extra money and get factory or forged pistons.

 

[mikyrc]

Hope the ITM ones aren't as weak as topline.

 

[90tsiPA]

I think any cast piston will fail if your motor detonates. When I bought my car the pistons that were in it had broken ringlands. I put in ITM pistons and ran great but the ringlands broke after 11,000mi(of constant beating). If my car was tuned I probably would still be running those pistons because my car detonated quite often. Topline and ITM are probably about the same quality and anyone can see failure if things don't run correctly

 

[mikyrc]

The question is, would a stock pistons support the same beating that ITM's weren't able to handle?
Or would them fail the same way too?

I mean if ITM are as good as stock ones then if i take care of detonation they should last right?

 

[Jrgunn5150]

The question is, would a stock pistons support the same beating that ITM's weren't able to handle?
Or would them fail the same way too?

I mean if ITM are as good as stock ones then if i take care of detonation they should last right?

IF you take care of detonation, any piston should last. The problem is that cast pistons are very brittle, one slip and they shatter. If you want to put your motor together, get a safe tune, and just drive it, it'll be fine. If you want to be swapping turbos and constantly chasing the highest dyno number/lowest ET, odds are you will go too far and pop them.

 

[90tsiPA]

I was very impressed with the amount of detonation the ITM's handled, I had a lot of problems with the car breaking up in the top end but i continued to beat on it, during last summer I went out racing almost every other night and if it started to break up i would keep in it. This time I'm putting toplines in just because i got them for very cheap from my friend. I am buying an eprom and getting a real tune this time around so i shouldn't have a problem for a while.

 

[96_turbo_spyder]

I recentlly re built my eclipse with abana motors they only use top line parts for the rebuilds... I ended up useing my stock pistons because they were in grate shape but every thing else is top line... I have now about 2000 miles on them and I am happy to say that the car is runnig grate its my dailly driver and I drive about 30-40 miles dailly mon- thurs and about 20 on the week ends.

 

[bbmop]

Ring lands breaking is usually due to one of several reasons which has nothing to do with name brand or manufacturer.

1) machine work on bore not done correctly, meaning Bore plate not used to keep bore line straight and round. When a machinist bores a block there is flex in the cylinder walls which can cause ovaling especially if a bore plate is not used. If this occurs you will have ring/piston faiure no matter what brand you are using.

2) Improper spacing from piston to cylinder wall. This usally happens when someone rebuilds a motor in the garage at home and hones the block not checking if the tollerances are correct. A ring gets caught on the cylinder wall surface during a high rev and Snap the ring breaks and so does the ring land of the piston. Does not matter what brand its going to fail.

3) Failure to remove the ring lip created in a used block on the cylinder wall. Its the area where your piston stops rising and you can catch it with your finger nail. What happens when you put a new piston and rings in the rings ae fresh and rise up and smack the lip on the cylinder wall. After a few hours of this you get rind land failure the rings break and the piston fails. Does not matter what brand its going to fail.

I deal with all these problems on a daily basis.

 

[mikyrc]

good Info bbmop.

 

[Anarchology]

Topline makes better than OEM replacement parts for the majority of JDM engines. They are still cast, but worth the money.

It may just depend on where you are looking to go with the car. If you are looking to boost the ever living hell out of it, then you might just spend the extra cash for some forged internals, but if just moderately boosting with like a Big 16g, then go with the Topline pistons.

Like I've said, they are OEM replacement, but better quality than what you would get from the dealer... Plus, buying from the dealer would only make you pay the same price as forged.

 

[dsmnightracer]

if you are going big, than don't use them.

 

[supersayianjim]

A coupule of months back modified(i think) magazine did a test on forged internals versus cast. and found out that forged pistons not oult handle boost better. but they also cool down the block(reducing temperature.

 

[SnowBird]

Why not just buy OEM pistons?