List & details of induction types

[AUS911SC3]

Hi All, I know there are probably copious amount of threads regarding induction, however can somebody please provide some collated info on all the induction types available for a '78 3.0lt. and their pros and cons inc. CIS. Obviously Im currently running CIS and for all the constant criticism they recieve I've had quite a good run however I would like to explore other options. Thanks heaps

[tcar]

You won't hear criticism of CIS from me, and a LOT of others.

Constant criticism??????

When people don't have problems w/ something, they don't post about it. So most CIS posts are problems. The tens and tens of thousands of us that have it with few problems don't really post about it.

You in Australia?

Why are you wanting to change? Goals?

[Scott R]

I have a perfect running CIS car as well. Been to EFI, to carbs, back to CIS now. CIS is probably the best of the three, given the nice cold and hot starts and ease of troubleshooting.

[James Brown]

Options you mean factory ones? there was only one-the CIS. If you want to custom options than just about anything goes. From carburetors like Zenith, Weber, PMO, Holley(?!) to MFI, EFI with superchargers or turbochargers. The Sky's the limit, meaning bring some cash!! Like most engines, if you make changes to one system (induction) you need to make changes to the other systems. If your happy with what you have, and it's working good, why change.

[Flieger]

MFI

[AUS911SC3]

Your right Tcar from Australia and it seems to work well in our climate, however i am about to venture into some track work and still after more power even after I've fitted SSI, reduced weight etc. Considering the limitations of CIS i thought another naturally aspirated option maybe worth looking at but Im unsure which. I have heard PMO's are very reliable and excellent for bolt on performance.

[Aurel]

Induction goes with cams. You won`t get much benefit from a more flowing induction if you don`t put more aggressive cams with it. Inversely, CIS does not work well with cams more aggressive than 964.

[Flieger]

Cams need piston clearance and compression to match. So, you need carbs, cams, pistons, and while you are in there an exhaust that can handle the increased flow.

the slippery slope

[RWebb]

Exactly.


But what are you trying to achieve?

CIS was a fine system in its time for an economy car, but cannot match a modern electronic FI system in any regard -- except that it will be a LOT cheaper to keep it.

Carbs are cave-man, but offer better throttle response and maybe more power for about $3,000 if you leave the cams/pistons alone. They suffer from emissions and cold start issues if those are important to you.