See your 292 Thread.

I was 70 by old VDO prior to nosecones and Stainless Marine exhaust. Maybe a true 67?

I did the exhaust, Imco Nosecones, and Nordskog GPS speedo all at once. Boat picked up 300 rpm to 5350 so I had to ditch the 23 Mirage (old style..original to the boat?) for Mirage + 25's. So now 70 on GPS at 4950. Would guess I picked up 3 MPH, 5 on a good day which I am happy with.

Do some searching aroung OSO. From reading other owners posts I probably should have gone with Hydromotive 4 blades.

Others know more about the Hydromotives than I do.

I've got your new speedo!! PM Me

Dave

My boat is a 1988 and has had motors installed. Said they where 420 motors by Carolina Performance . OK What I do know is they are Gen5 454,s no fuel pump mounting on block, With ( Zuzs ? ) Alui. intakes, with stock carbs and exhaust. It was pulling 5000 rpm not full throddle with the belts squeeling so that was that. Have just got boat back from shop to fox the steering and installed 25 p Mirage props. What is the difference in the + and the reg.

Hey Thanks for the link

What have you decited to do about the GPS. I want to buy one but have know idea . I have motor home that I would like to use it in, and on the boat. I was thinking battary, But they are to small to read ( old eyes). And the Boat and the Car have Cig. lighters for 12V. Help

Hijackers...all of you!

Anyway I monkeyed around with the speedo pick up tube, it had become disconnected. I reconnected the tube...but speedo still didn't move. I haven't determined if the tube is blocked or kinked or if the speedo is kaput.

I put that project on hold because the recirculating pump on the motor is leaking so that needs to get fixed first. It is always something.

You can check the gauge buy using an air compressor:

40 mph 21.84 psi
50 mph 34.13 psi
70 mph 66.89 psi
90 mph 110.56 psi

As you can see the small lines they put on these are usually not capable of the higher pressures. Most likely the line.

[QUOTE=SSComp]You can check the gauge buy using an air compressor[QUOTE]

Thanks for this info...I was wondering how to test the speedo...

Chuck,

I have a replacement VDO if you need it...PM Me

Dave