compression ratio

[safirenside]

Ok so I have a question sine im changing the stock compression ratio to JE 8:5 I was wondering if i would need a tune. In a later date I paln to turbo and get megasquirt but for now it will be a N/T.

 

[jayson427]

then you should wait till you get everything to go turbo. theres not much of a point to just rebuild the bottom end with low compression untill you can buy a turbo.

 

[g4ebguy90]

Isn't stock like 9 or 9.2:1 for the 420a?

You would not need a tune, but you will probaly notice a difference in regards to less off line power.

 

[96' Eclipse GS]

9:6:1 is Stock Compression Ratio.

 

[g4ebguy90]

That's a pretty good drop...

 

[Josh97eclipse]

No need to wait for the turbo to wait and build the motor. Built the motor now and break it in some (even tough breaking in a motor is a myth) I dont break them in nor does buschur. I drove my 8.8:1 motor unboosted for like 30 miles then i cam across a turbo kit for a decent price. I have been boosting 12 psi since 250 miles.

 

[LD25Delta9]

No need to wait for the turbo to wait and build the motor. Built the motor now and break it in some (even tough breaking in a motor is a myth) I dont break them in nor does buschur. I drove my 8.8:1 motor unboosted for like 30 miles then i cam across a turbo kit for a decent price. I have been boosting 12 psi since 250 miles.

It's not a myth, man. There is plenty of research to back up proper engine brea-ins. A lot of time the damage that is caused is microscopic at first, but it's been proven that the initial wear caused to the cylinder walls and rings during the break-in period can be drastically reduced with proper techniques and/or the use of certain additives such as ACES.

 

[safirenside]

So did you need a tune? I already have my pistions and rods and really want to get it running but if im going to need a tune ill just wait till I get megasquirt.

 

[LD25Delta9]

You can't tune our ecu's. They are not Eprom or reflashable. If you want more from an NA motor, the AFX ecu will give you a boost. I would save the loot for a MegaSquirt system, though. That ECU is tunable till your heart's content.

 

[Josh97eclipse]

Ha you are funny, Breaking in an engine......... Now read and tell me if its a myth, as long as its built right its not gonna break!

 

[1996Eclipse420a]

Well, I'd drive it like 300-500 miles just to make sure. That's kind of like saying you don't have to break in a new clutch. Whatever floats yo boat tho. Either way, i'd go the safe route.