What do you think

To put a turbo in a 10.1 motor

Sounds like you are crazy!!! JK :) But arent turboed cars usually given a lower compression ratio??

I've looked into turbocharging a 10:1 compression SR20DE, and although it is possible, you'd be well advised to get hold of a thick head gasket that will effectively lower the compression ratio a little. This will also be an uprated gasket, so hopefully you won't blow it out.

My estimates, along with UK Nissan tuners that I've spoken to, reckon that on 10:1 compression you'll be able to run about 5-6psi boost before you detonate that motor into the great car scrapyard....

To run high boost levels though, you will HAVE to lower the compression ratio to something like 8.5:1 or lower

Originally posted by Anthony
I've looked into turbocharging a 10:1 compression SR20DE, and although it is possible, you'd be well advised to get hold of a thick head gasket that will effectively lower the compression ratio a little. This will also be an uprated gasket, so hopefully you won't blow it out.

Yeah, it can be done, but I wouldn't do it. You'll be on the edge. As far as a thicker head gasket goes, I wouldn't do that either. The thicker head gaskets don't always seal so well and they reduce quench so it's a toss up anyway. Quench helps with detonation resistance. It's the pads in the combustion chamber that force the mixture towards the spark plug.

Anthony I think im going to get a GT exhaust manifold to go along with my back box. Is it just a straight swap or do I need to upgrade any other parts?

The GT manifold is a two piece unit, comprising of a 4-2 manifold and a 2-1 downpipe.

I have acquired a GT manifold and downpipe for my SRi, but haven't got around to fitting it yet. When I do, I'll let you know if both pieces are different, or if it is only the manifold that is.

BTW Neil, what on earth did your question have to do with turbocharging a 10:1 compression SR20? :confused:

Nout, I couldn't be arsed starting a new thread.:D

I remember you mentioning something about a new wastegate? ? Did u buy both the manifold and down pipe 2nd hand?

I got the manifold and downpipe second hand - £80 for them both :)

I am either going to buy a new Nissan one or get one from America, I will order it when I change my insurance to Elephant (£840 FC, full exhaust sytem,lowered,manifold,CAI, body kit, chip).


Was I talking bollox when i said "I remember you mentioning something about a new wastegate?" or was it a gasket?

Hi actualy I have a avc-r apexi subaru impresa "turbo" intercooler from this car too a cat back I have hear that a can run safe with 4-5 psi ,the problem is tha Im from Chile so is dificult to me get all the staff from jwt (ecu) and motors parts so Im plannig to do this worck by my self and friends AND olso have a fuel presur regulator variable apexi I dont wont a car with more than 200-210 hp can I run safe wiht the same injetors and maf do the maxima injertors fit in my 98 primeragx ?do i will need a MSD?4+psi will give me around 35-40 hp (with all the staff cat back cai etc)?some of my friend gime to me this staff(turbo ,intercooler)I also can put 108 oc fuel so the detonation will be olmost nule can I go with this project ?what do you think.Sorry for my english im learning.thanks in advance.:confused:

Neil - you were talking crap about me ordering a wastegate.... it was indeed replacement gaskets ;) Remember - wastegates are for turbos, and I don't have one (yet)...

If you are talking about buying new, then definately get a Hotshot (higher top end) or AEBS (better mid range) header as they are superior to the standard GT header.

Do you know if they come with down pipes? Also will I need new gaskets?

Yes, all the major aftermarket headers come with both manifold and downpipe. Most are two piece (4-2 manifold and 2-1 downpipe) but a few (like the AEBS) are one piece designs.

You should use new gaskets, as they normally cannot be reused.