Sigma-galant.com

Hi guys,

'84 Sigma SE (GK). 2L 4g63 8 valve SOHC Carby. RWD.

Just wondering if anyone on here is able to shed some light on carb setups for this engine?
What are the options? Is there a best option by far? Not looking at spending a $hite load..something cost effective with good results (i.e. better than what standard offers)

Any info. will be much appreciated.

Cheers.

Damn! Took the words straight out of my mouth! If you do the maths, a stock 2.6 as a daily driver (average 3500rpm) should need a carby around 170CFM. Based on 80% volumetric efficiency. Please correct me if I'm wrong, that's based on (Cubic inches x Max RPM) divided by 3456.
Didn' t they make a 180 Holley?
I agree, the stock carby "sucks" Anyone know the CFM rating of a stock sigma carbie?

Haha.. well.. I know my cars but that's giberish to me
So you're after a better carb setup for a 4g63 engine too? Or just for a Sigma with the Aussie engines?

I don't know about best carb set up but does anyone know the difference in throat sizes between a 2L and a 2.6? You could get a carb off a 2.6, put a kit through it and die grind out the throat ports in the manifold (unless there's a straight swap 2.6 manifold as an option). It'll look stock, no screwing around with trick manifolds and improve flow without being a dog to tune.

Might be an idea to read the post before commenting guys
He's in NZ, so his car has the same 8v SOHC 4G63 as our L300 van/L200 ute. So Astron parts won't work.

On topic, a 32/36 from a 2L Escort would likely work. They sell adaptor plates on Ebay as far as I know.

Well said webby

Did you NZ guys get falcons over there? 34adm webers work alright on the astrons, should be alright on the 63, give the timing a bump too

"Give the timing a bump"?? Please explain?

Haha webby cheers for clearing that up.
Yea at the moment car is fully tuned as good as she'll go - she's advanced quite a wee bit!

Yep we did get falcon's over here but I have no idea how easy it would be to find a part from them.

So there is no weber dual carb option of anything for these SOHC 4g63 8 valve engines?

As far as the escort and falcon go - do you guys know for sure they'll fit? Needing a definite answer so I don't have to buy bits here and there and trial and error what works with what - just wanting a quick carb upgrade that has (hopefully) been done before to help the girl breathe a bit better to squeeze a bit more response and power out.

Cheers!

Redline make an adapter plate to bolt on to the astron manifold that will take the weber from the falcon (which is a dual throat carb), and I'm fairly sure the weber from the escort would go on there too.

Even if the redline adapter doesn't bolt straight on, shouldn't take much to make your own adapter up.

Anyone have carby gaskets for a 4g63 & 4g5# they can compare

81GL wrote:Anyone have carby gaskets for a 4g63 & 4g5# they can compare

anyone?

I can go one better
I have a carby L300 manifold and a spare Sigma carby here somewhere, could have a look and see if you like?

webby wrote:I can go one better
I have a carby L300 manifold and a spare Sigma carby here somewhere, could have a look and see if you like?

Yea mate if you could have a look please that'd be great.
So the sigma carby you got what engine is that from? And the L300 has a 4g63 in it like mine right?

Cheers.

Webby would be referring to the astron engine range when he says sigma engine.

This is the adapter plate that is used to mount a weber onto the factory manifold.
http://www.ebay.com.au/itm/WEBER-ADAPTO ... 3f047f4c9d
You could probably ask this guy if he has any there that will suit your 4g63? he has them for saturns as well, so chances are good.

Nick.

Great will do that now.
Will let you know how I get on.
Cheers.