Ok I am getting different readings on boost levels. My AutoMeter says that I am in boost but the LED on the Crane retard box doesn't light up. It lights up at ~2-2.5 psi on the AutoMeter. So is the Crane off or is the Autometer off?

For those of you who don’t have or know about the Crane retard box it has an LED that lights up solid when the map sees boost.

It is weird though because the AutoMeter has steel braided line going to it w/ absolutely no leaks and the line is about 5' long. The MAP for the Crane is rubber fuel hose w/ no leaks and is about 4" in length. So how is the gauge that is 5' away from the manifold seeing boost before the Crane's MAP which is basically right off the manifold?

Any ideas?

TIA
Brian

What is your vacuum reading at idle(car is warm) on the autometer? Mine is usually around 18 at 625 rpm. If oil or any comtaminates get into the line, it could cause false readings on either device. When you shut your car off does the boost gauge go to .5 vacuum(not quite 0 psi-bottom of the box)? no need to answer if it works as advertised, just more things to think about.

Does the crane get its reading off of the map sensor itself? If so, maybe your map sensor took a shit and it is giving false info the the crane retard box. Is the crane box boost threshold adjustable or is it just off the map so when it sees boost, it then gives you a light saying it sees boost and start retarding.



Exactly what crane retard box is it(part number)? Is this just a retard box and not the entire crane distributorless ignition with retard option?

Kinda curious. I have seen the retard boxes and wondered how they performed.

I thought the Crane hooked up to a Crane MAP sensor you hooked vaccum to, and then wired into the ignition box. Then you adjusted retard when the Ignition sees boost. Depending on what sensor you have and how you wire it up, the unit can retard on a boost proportionate basis.

Either way, they light doesn't come on when the unit sees boost, but when it start to retard ignition timing. So the unit and your gauge may agree, but depending pon how you have things set or factory defaults from Crane, it doesn't start retarding ignition until after 2psi.



15.9 @ 86.7mph

Injen CAI, 55mm TB, P&P Intake, Crower Cams, Hooker Header, ERT/Catco Cat, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC