Calculating hp after slight rebuild

[ga129]

I'm currently looking at buying this guys 99 eclipse gs, I'm selling the one I have now due to mechanical issues. So he's told me that he rebuilt the trans with stock replacement parts. Then he bored it 10 over, put Eagle rods and pistons in it that he reconditioned after pulling them from a gst, replaced the valve cover, has added an Aem intake, headers (idk brand), left the cat connected. I'm still trying to talk to him but I'm not sure if he did any other internal work. So my question is: will the resulting power be very much more over stock, and would there be any effect on gas mileage? I've tried to find this info before but no luck. Also, the body has 130k miles on it and the "rebuild" has 8k miles on it
Thanks in advance
-Ga129

 

[grothe3297venge]

He reused parts from a GST and put them in his n/t? Did I read that correctly??

 

[ga129]

Edit: also replaced cams with stock cams and replaced all gaskets

 

[talonguy85]

If he put the pistons in a n/t from a turbo motor that doesn't make any sense. Our 4g63t engines have lower compression to compensate for boost. I would think you would actually lose hp unless this engine was being prepped for boost? Any thoughts on this?

 

[ga129]

He reused parts from a GST and put them in his n/t? Did I read that correctly??

That's what he said, I haven't gotten to see the car in person, but it runs so idk if that was a typo on his part or what

If he put the pistons in a n/t from a turbo motor that doesn't make any sense. Our 4g63t engines have lower compression to compensate for boost. I would think you would actually lose hp unless this engine was being prepped for boost? Any thoughts on this?

I was wondering the same


After I told him that I was glad that he did Boltons already and asked him about "rebuild", he said "yeah, all you need is a turbo"

 

[Abe'sGST]

If i were you i'd stay away from that car. If he said that about the pistons, it makes me think he had no idea what he was doing. And I'm not too familiar with the 420a but I'm pretty sure that those mods won't make much of a difference power wise. Only way you can really make a difference is going forced induction.

 

[glowryder]

^ This.

Your buying another "mechanical" issue..IMO if you cant fix your own car, you should just pass and buy something un-touched and RELIABLE. this car sounds very sketch and sounds like he has no clue what hes doing..

 

[ga129]

If i were you i'd stay away from that car. If he said that about the pistons, it makes me think he had no idea what he was doing. And I'm not too familiar with the 420a but I'm pretty sure that those mods won't make much of a difference power wise. Only way you can really make a difference is going forced induction.

^ This.

Your buying another "mechanical" issue..IMO if you cant fix your own car, you should just pass and buy something un-touched and RELIABLE. this car sounds very sketch and sounds like he has no clue what hes doing..

So the gst he was referring to was a gs that someone added a turbo to, he just didn't tell me that before, he just told me a few minutes ago, so now what are you Guys thoughts

 

[Jesse2012]

Still sounds extremely sketchy. I would never buy a 420a car from someone making huge claims about it unless you want to take the risk of buying a beat on half assed car.

 

[ga129]

Still sounds extremely sketchy. I would never buy a 420a car from someone making huge claims about it unless you want to take the risk of buying a beat on half assed car.

Yeah I'm going to try and test dive it this week and see how it runs, thanks for all the input everyone, anything else?

 

[91DSMdave]

He didnt use pistons from a GST, they would have to be .1 overbore 4g63 pistons, not gonna happen. Or the bottom end was a .040 over 4g64. Stock bore on a 420a is 87.5mm.

4g63: 85mm
4g64: 86.5mm
420a: 87.5mm

 

[bullettdsm]

He didnt use pistons from a GST, they would have to be .1 overbore 4g63 pistons, not gonna happen. Or the bottom end was a .040 over 4g64. Stock bore on a 420a is 87.5mm.

4g63: 85mm
4g64: 86.5mm
420a: 87.5mm

So the gst he was referring to was a gs that someone added a turbo to, he just didn't tell me that before, he just told me a few minutes ago, so now what are you Guys thoughts

I'd need more info on exactly what's in there. Forged? Compression? Actual overbore or just hone and go? JE? Wiseco?

Honestly, if I'm buying, I would consider the engine condition suspect and in need of repair. I would then look at the rest of the car as a whole.

At least do comp check.

MB

 

[ga129]

I'd need more info on exactly what's in there. Forged? Compression? Actual overbore or just hone and go? JE? Wiseco?

Honestly, if I'm buying, I would consider the engine condition suspect and in need of repair. I would then look at the rest of the car as a whole.

At least do comp check.

MB

##He said they are eagle rods and pistons, he bored it 10 over from stock, most of everything else was stock oem replacement, it's a 420a and I believe stock heads.
That's why I'm going to drive it and maybe even have others look at it too, he says that he's put 8000 miles on the work already, so Atleast we know it runs, what do you mean comp check, like obdII scanning?

 

[mac 108]

##He said they are eagle rods and pistons, he bored it 10 over from stock, most of everything else was stock oem replacement, it's a 420a and I believe stock heads.
That's why I'm going to drive it and maybe even have others look at it too, he says that he's put 8000 miles on the work already, so Atleast we know it runs, what do you mean comp check, like obdII scanning?

Don't buy this car. You're wasting your time.

 

[Fotowntalon]

I was unaware eagle made pistons. Everyone on here has told you to steer clear, but its a waste of time, you already have your mind made up....

 

[BogusSVO]

Sorry.... this makes no sense to me... Bored 10 ? as in .010 over?

I have never seen .010 pistons, unless they are one off customs, never an "off the shelf" piston.

Its about next to impossiable to bore .010... If the block had a min of wear, lets say .003 -.004
That leaves .007 - .006

When you bore a block, you leave appox .003 to hone the machining marks out of the cylinder bore.

so now that leaves .003-.004 to be bored out

Now cut that in half, the amount of metal to be bored any 2 points 180* out, so thats .0015 -.002

So if the set up is off in any way, you will have a egged shape bore.

Now if he said the block was honed .010 to take it from .020 over to .030 or .030 to .040 That I can understand and accept.

 

[ga129]

I just want to thank everyone for the time and replies, I truely appreciate it, I want a car that I can depend on to be reliable and have decided to just leave this one be.
Thanks everyone
-Ga129

 

[jayson427]

just keep saving up your money for an eclipse that is worth it. you will find a better car down the road.

 

[99 gs iowa]

gst internals in a gs? wow what a joke, that car sounds like a serious scam

id say by hearing that you believe that those internals would work in your gs, u need to buy a stock car and do ALOT more research, 4g63 parts arent meant for the 420a, its not like the honda platform