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Ej18 with EJ20 Pistons and rods, its possible?

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Hello again, i have troubles with my GC6 and i have to change the pistons and the rods of the EJ18, so i bought the EJ20 pistons and rods to install on the OEM EJ18E block, can i bore the EJ18 to 92mm? i need to know if this will be possible, and if i have to change the sleeves of the cilinder to, ty for attention and sry for my bad english.

Edited by Marter_Templar

you would probably have to resleeve it i would think...might be easyer to get a EJ20 and swap your heads and intake manifold onto it...lol plus you would get a high compression motor because the EJ18 has a smaller head volume than a EJ20....high compo= good for alcohol blend fuels you guys get in brazil

Edited by LPGsuperchargedBrumby

Yep as he says. The liners are only 4-5 mm thick so if you want to go from 87.9 to 92.0 you'll end up with only 2 mm thick cylinder walls - which is very good for cooling but a lot less for reliability!

  • Author
you would probably have to resleeve it i would think...might be easyer to get a EJ20 and swap your heads and intake manifold onto it...lol plus you would get a high compression motor because the EJ18 has a smaller head volume than a EJ20....high compo= good for alcohol blend fuels you guys get in brazil

 

yep, but here in brazil its to expensive to get an EJ20 Shortblock, and its much more cheaper to bore the EJ18, i will take some like 10,5:1 of compression with the EJ20 pistons and the EJ18 headers , i will look for the sleeves here in Brazil, tks for helping.

 

Yep as he says. The liners are only 4-5 mm thick so if you want to go from 87.9 to 92.0 you'll end up with only 2 mm thick cylinder walls - which is very good for cooling but a lot less for reliability!

 

hummmm, so the EJ18 sleeves can hold the EJ20 pistons ? the car will stay original i am not thinking to put an turbo in it...ty for help

Edited by Marter_Templar

If you aren't turboing, then why the EJ20 pistons?

 

You should return them and get some standard EJ18 pistons.

 

And just for the record, what are you doing to the poor N/A EJ 18 that you need to replace pistons and rods? Rods could be from lack of oil changes, but why would you need new pistons. If anything ReRing the ones you got and slap some new bearings in and go.

 

Trying to use ej20 pistons seems pointless.

  • Author
If you aren't turboing, then why the EJ20 pistons?

 

You should return them and get some standard EJ18 pistons.

 

And just for the record, what are you doing to the poor N/A EJ 18 that you need to replace pistons and rods? Rods could be from lack of oil changes, but why would you need new pistons. If anything ReRing the ones you got and slap some new bearings in and go.

 

Trying to use ej20 pistons seems pointless.

 

its not pointless, 1800cc its less than 2.000cc , with this simple "change" my car will gain some close to 15hp , i will have more compression ratio to use Etanol, so with the 200cc more and the 1~1,5 more of compression ratio (because i will keep the stock ej18 headers) , i wiil have an motor from 105 hp stock to 125~130 hp with etanol.

its not pointless, 1800cc its less than 2.000cc , with this simple "change" my car will gain some close to 15hp , i will have more compression ratio to use Etanol, so with the 200cc more and the 1~1,5 more of compression ratio (because i will keep the stock ej18 headers) , i wiil have an motor from 105 hp stock to 125~130 hp with etanol.

 

Simple? Boring two or three mils out of an engine block isn't very simple. It won't be simple to fix when it grenades because the sleeves are too thin. Import a used EJ20 block. It'd cost you less in the long run.

 

Also - I wouldn't even bother splitting a block to gain 15HP. Why not just slap a turbo on it?

In that case why not source a complete EJ22 longblock and swap it in? No wiring issues etcetera and 30 hp gain over stock.

  • Author
Simple? Boring two or three mils out of an engine block isn't very simple. It won't be simple to fix when it grenades because the sleeves are too thin. Import a used EJ20 block. It'd cost you less in the long run.

 

Also - I wouldn't even bother splitting a block to gain 15HP. Why not just slap a turbo on it?

 

the only problem of installing turbo is that in Brazil the law doesnt allow it, i am thinking on getting the EJ20T forjed short block and putting all other pieces of my EJ18 Headers, air intake , ECU, etc..., do u think my original EJ18 ECU can manage that change? , tks

 

In that case why not source a complete EJ22 longblock and swap it in? No wiring issues etcetera and 30 hp gain over stock.

 

Its to hard to find a complete EJ22 here, i thinking to get a EJ20T forjed short block that are selling here in Brazil, do u think the original ej18 ECU will handle that system? tks

its not pointless, 1800cc its less than 2.000cc , with this simple "change" my car will gain some close to 15hp , i will have more compression ratio to use Etanol, so with the 200cc more and the 1~1,5 more of compression ratio (because i will keep the stock ej18 headers) , i wiil have an motor from 105 hp stock to 125~130 hp with etanol.

 

Sooooooo much work and really you won't notice any difference when driving it.

 

Oh yeah, until it blows.

 

Honestly I don't even think there is enough material to bore out, the limit listed by FHI is .50mm so this is all an irrelavant discussion.

  • Author
Sooooooo much work and really you won't notice any difference when driving it.

 

Oh yeah, until it blows.

 

Honestly I don't even think there is enough material to bore out, the limit listed by FHI is .50mm so this is all an irrelavant discussion.

 

i am thinking on getting the EJ20T forjed short block and putting all other pieces of my EJ18 like Headers, air intake , ECU, transmission, etc..., do u think my original EJ18 ECU can manage that change, and the transmission its plug and play? tks

The ECU will run any normally aspirated engine up to even the EJ25.

 

If you want to stay n/a I wouldn't spend too much on a shortblock - and there is no such thing as a forged EJ20T unless you mean the semi-closed deck EJ207 STI engine 2001 and up. It has forged pistons and decent rods, all previous STI engines had/have the same crappy rods as your EJ18 and only some (STI V3 and up) have forged but heavy pistons.

  • Author
The ECU will run any normally aspirated engine up to even the EJ25.

 

If you want to stay n/a I wouldn't spend too much on a shortblock - and there is no such thing as a forged EJ20T unless you mean the semi-closed deck EJ207 STI engine 2001 and up. It has forged pistons and decent rods, all previous STI engines had/have the same crappy rods as your EJ18 and only some (STI V3 and up) have forged but heavy pistons.

 

i think i will simply rebuild my EJ18 engine and later put a turbo on it, ty for the infos...

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