:sad:Put a March billet pulley system on the car. Looks wonderful, but..........
not putting out enough electrical juice or water flow with the underdrive crank pulley. It is 5 1/2".
Engine gets hot idling and the water barely flows in the radiator. Engine just gets hotter.
Amp gauge working well but shows a little towards discharge at idle from the middle. Rev the engine and it jumps towards charge.
Disconnect the neg cagle at the battery and the engine dies unless you rev it just a little and then it stays running when pulling the neg cable.
Brand new Alumnitech radiator. Brand new waterpump and thermostat. Thought it would still cool. Maybe it would running down the road. Don't need to take the chance.
I guess I will order the overdrive unit which is a 7 inch crank pulley today.
Anyone want to buy a new underdrive pillet crank pulley?
Live and learn.

Hmmm. I am running a stock napa water pump and the march underdrive pulley set. I have just barely enough charging at idle, and my car does not overheat idling unless I were to let it sit for 20 minutes. I have stock shroud and fan and aluminum radiator.

Brett,
Pretty much my problem also. I have not driven yet. Got my insurance and tag a couple of days ago. Gotta put the interior in.
Gonna drive it Saturday to get seat studs welded in. Gonna just set the seat in. 4 miles.
I ordered the 7" crank pulley today from Summitt. Cheaper than straight thru March.
The engine shouldn't have to overheat even if idling for 20 minutes. I have been real picky about everything on this restoration.
I started to get the smaller WP pulley also but thought I'd try this first.
Nice burnout.

Thx Herbie. I originally just tried to change my crank pulley, found out that they spaced it different from the stock stuff requiring you to run all their pulleys. Just warning you that maybe the belt will no long be alinged if you are trying to now run a wp and alternator pulley from march and no their crank pulley.

WHOA! I just realized the other day that I have the same problem. What kit did you order?

My kit said "performance ratio" so it is my fault. I tried to find a 7 inch pulley but my kit uses a 5 rib belt for the power steering and the 7 inch peulley uses two 6 rib belts.

WHAT DID YOU EXPECT when you install underdrive pulleys ,the motor runs hotter due to reduced w-pump rpm and the battery isnt charged properly due to again decreased alt rpm,and they never tell you that will happen either because they want to make sales.

Also,NEVER EVER REMOVE THE BATTERY CABLE/S FROM THE BATTERY WHILE THE MOTOR IS RUNING TO TEST THE ALT ,THAT CAN AT TIMES BLOW THE DIODES ETC IN THE ALT RUINING IT.

Reinstall the correct pulleys to correct the problems and dont worry about the 5-10hp you may loose when runing the correct /stock pulleys.

Scott

Or get the stock diameter pulleys from March if you want the look of billet pulleys.

I had the kit from March ordered through Summitt.
Everything should line up as the WP, PS, and alternator are the same. All are billet from March. Only difference is that the new pulley coming is a 7 inch and I will be taking the 5 1/2 inch off.
Hey what can I say? I am learning as I go. I was talked into getting the underdrive system.
Reason I posted this was to warn others of the down side.