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L24 Compression Problems

OUTATIME
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OUTATIME Community Regular

OUTATIME

Posted
Posted

atm have a l24e+t that likes to ping is ass off over 6psi. compression accross all 6 is between 168-172psi. head was rebuilt few months ago and i think too much was machined off.

im wanting to lower the compression so thinking either thicker head gakset or a shim.

what would b the better option? whats the std thickness of a l24 head gasket? how much thicker (if possible) should i go? also any thoughts on these shims? seen them b4 just thought was dodge that they r glued to the block (1 i saw done one a gemmie anyway). guess two flat serfaces so should seal alight under boost?

but yea any info would help me out heaps

cheers...

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Factory 5 Mentor

Factory 5

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Posted

if you have the E88 head, it is lower compression than my N47... so Im officially worried!

I think if you get a gasket taken to a metal laser cutting/waterjet place and get them to make up a 3mm copper gasket to start with

(i think the HKS ones were 3mm)

i think if you get a N42 from a L28 it might lower the comp a bit....

Ghostridcer will know.

blind_elk Grand Master

blind_elk

Posted
Posted

I was warned, by a knowledgeable person, when I proposed this some time ago that the engine would likely ping because the head wasn't designed to handle a turbo.

What ECU are you running? How much was shaved off the head? And did you pack the cam towers to compensate? (maybe the cam timing is "off" (retarded))

Why not get a head from a wrecker, get it machined (port, profile combustion chamber) to suit a turbo app. Might be a bit more expensive, but I'm sure it would be a better outcome in the long run.

I think a L28 head is unsuitable because the L28 is a bigger bore than the L24 (?)

OUTATIME Community Regular

OUTATIME

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  • Author
Posted (edited)

cheers 4 the feedback, yea have read about the combustion chamber being unco for boost (half moon) but mate is running l24et n47 head, 10psi no worries. smaller injectors, smaller turbo and fmic and stock ecu. (u should b ok andrew lol)

im only runnin stock ecu.

no idea how much was taken off the head and theres no packing under the cam towers. timing is spot on tho and chain is tight. unless need a vernier cam gear if its a pooftinkths out?

the head its self is good (just been rebuilt) so was hoping to use thats still with maybe a spacer, thicker gasket etc. or after market ecu would be the better option?. but then if comp is too high still wont b able to run much more boost?

1st ill borrow some IPA from work and test out this water injection set up as metho didnt work lol. was alot better but still ping country after 5k...

Edited by OUTATIME
OUTATIME Community Regular

OUTATIME

Posted
  • Author
Posted

with alcohol in there it deff did make a power difference but still pings after 5k.

thinking about a adjustable fuel reg. to richen it up when on boost. cos plugs r white after a thrash, black after puttin around.

http://cgi.ebay.com.au/New-SARD-Adjustable...1742.m153.l1262

any1 had any experience with those regulators? worth getting 1? i had a cheap ass monsta one b4 on my 31 but did f*k all and just broke in the end. dunno if it was a rising rate or not.

cheers...

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