[JH1711]

hi guys so my built ej205 is basically back together and I’m having valves hit pistons
RCM street forged 2.1 stroker kit 90mm bore
Come with forged rods , pistons and heat treated ej25 crank (79mm rather that ej20 75mm)

Hitting valves to pistons with stock cams let alone the bigger ones I spent money on

I’ve got the timing done right to Subaru specs

Where I think my problem lies is with the crankshaft but I’m just wondering if anyone else has had this problem ?

 

[zax]

Yes, piston-to-valve clearance is an issue to consider since you are adding an additional 2mm of interference if using stock rod length.

EJ205s in the USA did not ship with Cam Phasing tech. I see you are not in the USA so this is probably something additionally you need to be concerned with.

What pistons? What rods? What camshafts?

Not sure how you ended up with a 90mm bore when the OEM block is 2mm wider.

 

[JH1711]

Hi Zax

Sorry I meant 92mm haha

The stroker kit includes

Manley Conrod Set

• Manufactured from 4340 forgings.
• Heat treated, stress relieved, shot peened and 100% magnafluxed.
• Weight matched sets + 1.5 grams.
• 3/8" ARP 2000 bolts.



RCM / Omega Forged Pistons

• Forged from 2618A aerospace alloy.
• CNC machined at a constant 20.5°C.
• Weighed and batched to within 0.5 grams.
• Piston sets are supplied with piston rings, gudgeon pins and circlips.

The cams I’ve purchased are

Kelford cams 199C
268&264/264 Degrees advertised duration. 10.30mm&10.00mm/10.00mm lift.
The cams fit but they r just too big with the 79mm crank and even with advancing the timing it still hits valves to pistons

I believe if I switch back to my ej20 crank that I might get the clearance I need maybe with some advancing (hopefully I don’t need to ) but that would ultimately make my build a forged 2.0 rather than 2.1 which then I spent more money then I should have haha 😭😭😭😭😭