View Full Version : SR Bottom end/ 1.6 MPI Head
Right, ive got a 1.6 GSi lump with a dead bottom end! Will the head fit onto my 1.4 SR Bottom end?
Is this a worthwhile modification?
What head gasket do i use?
What cam belt do i use?
What Head studs/bolts do i use?
T40s a good option?
What cam can i use, Performance wise?
What sort of performance bhp/torque can i expect form this set up?
Bearing in mind im using a GSi Manifold and downpipe with a mongoose stainless system
All help greatly appreciated
Yep the head will fit, it needs a megaskim to get compression back to "normal" 1400 ratio tho.
IIRC, about 15thou skim, gets it back to SRi compression. Depends if the heads been skimmed before tho.
1400 headgasket
Normal 1400
Normal 1400
Yes
Piper BP285-300/Kent AST2
Around 100-110bhp, depending if you get the head skimmed etc.
Right, ive managed to get hold of
Sport 40s + linkage
Irmscher inlet manifold
Irmscher Air Box
282 Cam
Ashley 4-1 Manifold
Will all this be suitable for the MPI head?
Is head work a good idea?
What sort of price am i looking at for a head skim?
What sort of figures will this little lot produce?
You'll need a different inlet for a gte head.
A head skim was ?29 last time i got a quote.
The std mpi head is very good flowing and doesn't really need headwork, should help tho.
Probably about 100-115bhp.
Its a GSi head
How much do i need to skim by?
Why do i need different inlet manifold then?
Yes you'll need a gte/gsi t40 inlet with round ports.
If its a early gsi engine then its the same as gte, e16se.
Apparently a 15thou skim(on a std head) gets compression back to normall 1400 level.
id "over" skim it a little BUT incase the ehad has been skimmed before id measure the CR and get the head skimmed by the right ammount and not a guess. there is a guide on how to measure CR in my sig link 1.4 tuning guide.
id personally go above std 1.4 compression if using a 285 cam and 40's, just to get that little bit more from them as the cam effectively reduces the dynamic compression ratio ;)
What would you consider a safe CR for a 1400 on 40s?
depends on the cam but id say anywhere upto 11:1 if youve got someone very GOOD setting the fuelling and Ign up... but for safety id err to 10.8 as a max
I think the std 1400 compresssion on SR/spi engine is about 9.4, slightly higher for 14se.
Would be best measuring the current cr as said and see where the current sr block and gsi head leaves it.
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