nt 4g63 pistons

[lq1driver]

Ok guys ive done my research and im still uninformed. I have the connection on a non turbo 4g63 with about 35k on it. my 7 bolt blew apart this week so im looking into my options. will the non turbo pistons take 20psi from a evoIII 16g and last. i know all about the motor not having oil squirters and everything. i also know that the evo III had 9.0-1 compression and so does the non turbo block. will these pistons fail on me or will i be ok, or should i just try to put a set of 2g pistons in it. my build plans are as follows. 6 bolt block 2g head 1g cams evo III intake exhaust and turbo, and probably arp fasteners ?

 

[bastarddsm]

If you keep it from detonating yes...enough detonation will kill any piston.

 

[lq1driver]

i run 93+ octane i also run some pretty agressive timing but i could probably tame it down

 

[bastarddsm]

Well th only time ive ever seen a n/t break was when some one was trying to break it....lots of boost+ nitrous, ect...

 

[r1991_4g63t]

the NT blocks dont have oil squirters, which are a pretty good idea on stock internals, weaker ringlands, higher compression and no knock sensor.

 

[lq1driver]

i see your running a non turbo with turbo what turbo are you running and how many lbs of boost

 

[bastarddsm]

the NT blocks dont have oil squirters, which are a pretty good idea on stock internals, weaker ringlands, higher compression and no knock sensor.

They DO NOT have weaker ringlands. The crown is a lil thinner around the edges, but its not a huge concern. He will also have a knock sensor. If you have not run a n/t shortblock, I'd prefer you kept your mis information to yourself.

 

[bastarddsm]

i see your running a non turbo with turbo what turbo are you running and how many lbs of boost

I run 15 on the street daily, I have more agressive 1g timing, so I can't get away with as much boost. However my car sees 20+ on the stock fuel system often. It has also survived a few excursions into 30psi territory when the wastegate line blew off. The only time my car gets knock is when I bounce it off the revlimiter when shifting. My car also has a shaved head so my compression is like 9.5+:1.

Currently the car is getting put on the corn juice, and i'm shooting for 12's on E85 with the factory injectors, factory ecu, and no safc/maft ect...

 

[lq1driver]

im lookin for 300hp think the n/t block can handle it? also daily driver during the summer

 

[bastarddsm]

Thats exactly what i'm shooting for with mine. Just watch your knock.


What are you paying for the 7bolt... I have bough n/t shortblocks for as little as $40 One thing you will need to watchout for is that its still a 1g 7bolt, so its not a drop in affair. But with only 35k miles its just getting broken in...

 

[lq1driver]

im on dsm link i was running 25psi on 14b i didnt get any knock till it spiked to 27psi and said BOOM im gonna go for 20 psi on evo III i dont think it should be a problem i also am planning on running corn juice as soon as our local sheetz gets it the only place for me to get it around here is 45 mins away then 25psi all day

 

[bastarddsm]

I'd probably pull a couple degrees of timing at the onset of boost fading to 1 degree less at redline, just to be safe...


Edit, You were probably on the ragged edge of destruction...I'd pull at least 3-4 degrees across the bord and go from there.

FYI The oldschool v-8 guys liked to pull 1* per pound of boost..

 

[yesItsdsm]

What about using non-turbo pistons in a turbo block? Anybody know how much they can take?

Since they would be in a block with oil-squirters and a knock sensor, shouldn't they be able to handle more horsepower than in their stock block?

 

[kris_stewart10]

how many psi can the N/A pistons take without detonation????? thats what i want to know

i am curious too i want to put higher compression pistons in my car so i can get my turbo to spool quicker

 

[1qkfwd]

Bastardsm hey have you ran into any head gasket problems runing a non turbo engine. I put a turbo on a non turbo engine when I first crossed over. I personaly had some coolant seepage which caused the car to overheat going up into the mountains. I wasn't gonna be stuck on the side of the road so I let it over heat to get me to the top. The engine was so hot that I barely would give it gas and you can hear the car pingin. I let it cool down filled it with water and went home. For a month after I raced a lot and beat up on that engine. It blew oil all over the place. I pulled the pan and droped a rod and piston and the ring land fell apart with the upper rings. I wish could have kept the car running good I believe that it can hold some power after what I put it through if it was tuned.

 

[lq1driver]

from what i understand thier is a spot for a knock sensor on the non turbo block the only difference in the engines is the pistons and oil squirters and detonation is based on alot of things timing boost intake temp type of fuel ect. im kinda leaning torwards this set up but using meth injection for my race tune which will probably be 22 psi in the head they have different cams, and injectors

 

[yesItsdsm]

Everyone is talking about what the nt pistons can do in the nt block. What about in a turbo block with a good tune, oil squirters, and a knock sensor

 

[lq1driver]

all im interested in is can they take 20 psi from an evo III or not and who if any one has tried it i know the blocks are the same cranks the same rods are the same can the pistons take it or do they need to be swapped for some 2g 4g pistons

 

[bastarddsm]

Bastardsm hey have you ran into any head gasket problems runing a non turbo engine. I put a turbo on a non turbo engine when I first crossed over. I personaly had some coolant seepage which caused the car to overheat going up into the mountains. I wasn't gonna be stuck on the side of the road so I let it over heat to get me to the top. The engine was so hot that I barely would give it gas and you can hear the car pingin. I let it cool down filled it with water and went home. For a month after I raced a lot and beat up on that engine. It blew oil all over the place. I pulled the pan and droped a rod and piston and the ring land fell apart with the upper rings. I wish could have kept the car running good I believe that it can hold some power after what I put it through if it was tuned.

Nope I have never had any headgasket problems with a n/t motor. You might have had a HG that was marginal to begin with. I have had good luck with ajusa gaskets. Currently I am running a really cheap chinese gasket..we'll see how it holds up.

 

[1qkfwd]

all im intrested in is can they take 20 psi from an evo III or not and who if any one has tryed it i know the blocks are the same cranks the same rods are the same can the pistons take it or do they need to be swapped for some 2g 4g pistons

I wouldnt go with the NT pistons if you are wanting 20psi. They are not that strong. I would say that they are more for the 10-15lbs range well tuned.

 

[bastarddsm]

Everyone is talking about what the nt pistons can do in the nt block. What about in a turbo block with a good tune, oil squirters, and a knock sensor

I would speculate the same, as a turbo, same as a n/t. The detonation might be a little bit easier to avoid with the squirters. The knock sensor is a non issue. All 4g63 blocks have a spot for it.

 

[bastarddsm]

Detonation will kill either turbo pistons or non turbo pistons. For the goddamn 9 millionth time: TURBO PISTONS ARE JUST AS STRONG AS NON TURBO PISTONS!!!!!!! However, with the increased compression they are slightly easier to detonate, especially with a 1g's agressive timing. Every piston that gets broke shears the ringland off between the first and second compression ring. These are the same exact size as the turbo pistons. END OF STORY!

 

[yesItsdsm]

Detonation will kill either turbo pistons or non turbo pistons. For the goddamn 9 millionth time: TURBO PISTONS ARE JUST AS STRONG AS NON TURBO PISTONS!!!!!!! However, with the increased compression they are slightly easier to detonate, especially with a 1g's agressive timing. Every piston that gets broke shears the ringland off between the first and second compression ring. These are the same exact size as the turbo pistons. END OF STORY!

Finally somebody could clear that up for me.

Now I am gonna have to toy around with some nt pistons, Looks like a cheap way to get a bump in compression

 

[lq1driver]

id be interested in seeing if some one had 1g nt piston and 2g turbo piston and seeing the size difference on the ring lands and mic them out to show size also are either piston forged?

 

[1qkfwd]

Detonation will kill either turbo pistons or non turbo pistons. However, with the increased compression they are slightly easier to detonate, especially with a 1g's agressive timing. Every piston that gets broke shears the ringland off between the first and second compression ring. These are the same exact size as the turbo pistons. END OF STORY!

Agreed with this and all is true. Detonation will kill any engine. Using these would be like puting a turbo on any N/A engine. Yes you can make power but it is like walking on thin ice. I just say this from personal experance that I have had non turbo pistons fail sooner with heavy detionation spikes and over heating than with the turbo pistons. I am not talking about the compression ratio differance or none of that. So that would make them weaker than the turbo pistons only because the ring land is higher up on the piston making it more prone to be affected by detonation. I believe that the only reason that there is such a high failure rate with the N/A 2.0 is that knowone compensates for the higher compression and doesnt keep an eye on there knock. I don't know how much power that they will hold quite yet. Have you found that threshold yet? I am experimenting with that right now with a G4CP engine out of a N/A sonota. This is the same bottom end as a 2.0 1st gen short block.