Turbo tb 45 compression

[mudbug]

Hay guys could some one lead me in the right direction , I have a TB 45 with a garret turbo stuck to the side of it placed in a GQ wagon , the patrol goes great but the compression from the standard motor is to high and pings every now and then I am running 9 pound max (with a modified fuel rail and injectors, it also has 42 rods for added strength) but want more . I have to remove the head due to oil leaking from the front of the head and block , what might be the best way to reduce the compression : thicker head gasket , do some head work , or maybe looking at different pistons and where could I start looking , I am from Adelaide

cheers
ready to pop !!

[nissannewby]

Is it intercooled? What size turbo?

[mudbug]

yes its intercooled and a garret 3582 ballbearing

[nissannewby]

Yeah I would be looking at custom pistons to suit.

[BigRAWesty]

Is decompressing the way to go? To me that's just offsetting the turbo so why not just turn down turbo?
Could it be more timing or Fuel mixture?

[nissannewby]

Is decompressing the way to go? To me that's just offsetting the turbo so why not just turn down turbo?
Could it be more timing or Fuel mixture?

On a petrol it is, it's already on the low side for that setup boost wise. He could get the tune looked at and make sure its nothing simple like timing. If it hasn't had the compression lowered then what they do is basically start to diesel (compression ignition) so it's already starting to ignite before its even sparked.

[Ben-e-boy]

big rig had the head done. I think its about 7.8:1 but he still had to take some timing out as it was still pinging. the mechanic would have prefered about 7.5:1 so some decent timing could be put in to it

[Alitis007]

You could fit a Cometic layered steel head gasket so it will act like a decompression plate, i had a 1.9mm thick one on my vl to lower the compression enough so it wouldn't ping but i don't know how that will affect the push rod length. To do it properly you should fit some low comp pistons but that would be a 2k exercise but you will have piece of mind knowing its done correctly.

[davo94]

Talk to any smart engine builder and get you compression chamber cc'd mod the head to lower the comp slightly and ensure the flame front is correct. Get a mls head gasket slightly thicker than standard. Have you looked at a tune if so ditch the maf and map tune it.
Are you running standard fuel pressure? Whats your air fuel ratio (with wide band installed)

[05_ENFORCER]

As davo94 said, if you have the head off, talk to a head guy.
If you were in W.A I can point you in the right direction.
You may as well grab some head bolts and a Cometic head gasket also


.