I am considering installing Gami injectors on my Twin Comanche, non-turbo. I would apreciate fedback from those who have experience with them. Smoother running ? Better fuel flow ? Worth the investment ?

Thanks,
Tom

I installed them on my single and really could tell a difference. So when I purchased the twin and subsequently had to do 2 engine overhauls I installed them at that time on my normally aspirated PA39.

On both engines I have their respective cylinders peaking within about a 0.3 gph range... I burn at peak...and at 9,000' WOT 2450 RPM that translates to < 15 gph combined...

I know that I have "happy"engines... the temps are pretty darn good, (I have one cylinder #4 on the left engine that burns a bit warmer than the other 7 cylinders).

If you can have you cylinders peak with that tight of a range you probably don't need them.

Jim

Tom,

I put GAMIs on after an overhaul as I wanted to keep the cylinders as happy as possible. I can't really say I noticed any appreciable difference. The true test would be at the next overhaul so I really can't say yes or no - I will say with each cylinder having a corner, the think the benefit to a 4 cylinder engine might be less than a 6 cylinder. Used to race these same engines at max power.

Knowing what I know now, I'd spend more time and money putting excellent flexible baffles for great cooling. Just my opinion - hopefully others will chime in.

Tom,
The purpose of the GAMI's is to make the cylinders work as "one", or in respect to when they peak.
Normally as you lean our 4 cylinders, they are all rich, keep leaning, then the first one peaks, then the second etc....
This is the GAMI spread, or the difference in fuel flow between the first and last to peak.
So prior to anything, GAMI recommends you go out and find the spread. If your spread is small, don't bother with GAMI injectors.
Some people play w/ their present injectors and get the spread down to a minimal.
I ran pre gami tests, and had a small range of gami spreads...but ...
I had gami's installed anyway, and the range is NOT perfect, and I could play all day by swapping injectors etc...
or i could be happy w/ what i have.
Run the gami pretest, take someone with, hope you have a JPI w/ fuel flow, or some digital meter, really helps...
steve

Thank you for your input everyone.

Tom