1970 Ginetta G15

Pictures of the completed pedals turned up.








And here are the Toyota wheels mentioned previously - drop me a PM if interested.








Body on chassis lifting duties tonight up at Itchy's place.

I find a good tidy up and a bit of working space can really fire projects forward!

Those Toyota wheels are ace too, centre caps and all!

Spent the evening with Itchy and bizzo yesterday testing Hillman Imp water pumps. Looking at the sheet of paper I have in front of me I am surprised to find that we managed to test 8 pumps.

Out of the 8 it looks like only two were original Chrysler casings the rest being Quinton Hazel item or unbranded without markings.

Sorry for the lack of photo's on this - a description will have to do unless we do some further tests.

Basically we had a header tank reservoir to provide a full flooded suction to the pump. The pump outlet was connected to a pipe that had a section of clear PVC tubing that was run vertically so we could measure the head generated by the pump. The pumps were powered by an electric drill onto the pulley nut. Drill was run at the maximum RPM - approx. 3000. The pulley sizes on a stock Imp motor run the water pump at about a 10% underdrive compared to the crank so the 3000 was about 3500 RPM or in a G15 56 MPH in top.

We had a bit of a false start with the comparisons when I found the drill was not set to maximum so we had an initial low readings.

Pump 1 - Bizzo (QH)- Reconditioned pump - Measured head Low RPM - 780mm
Pump 2 - Bizzo - Original pump on PHX - Measured head Low RPM - 860mm - High RPM - 2100mm
Pump 3 - DS-1 (QH) - Measured head high RPM - 2190mm
Pump 4 - Itchy 1 - Measured head high RPM - 2000mm
Pump 5 - DS-Chrysler Original - Measured head high RPM - 3400mm ++
Pump 6 - Molebert - Chrysler rebuilt - Measured Head high RPM - 2400mm
Pump 7 - DS-2 - Measured head high RPM - 2310mm
Pump 8 - DS-Crusty (QH)- Measured head high RPM - 2100mm

The output from the original Chrysler pump took us all by surprise - over a Metre head better output than the best of the rest. I expect it was around 3600mm WC

Most pumps tested at 3 - 3.5 PSI The Chrysler pump measured 5PSI nearly 50% more pressure.

We also found that the higher performing pump also had a smaller diameter pulley fitted ! Not that it made any difference in the test as we were spinning a nut not a pulley. However, now need to find out out what engines had a small water pump pulley.

The Imp cooling system does not have a great deal of pressure drop through it, as like a "normal" system the rad is right next to the engine - The G15 however has a lot of coolant pipes connecting the front to the back. With that layout there is a far great requirement for pump pressure in order to overcome the flow restrictions, especially when you have more than doubled the heat output from the engine by tuning.

I had always understood that the QH pumps were not quite as good as the factory pumps and a lot of what we have found here bears that out. Just need to figure out why.

Also worth noting that a smaller pulley diameter on the pump not only increases the pump speed and output but also the fan speed. Wondering if the smaller pulley is off a van.

Most of the impellers are cast but I have come across plastic as well

At least one of the impellers in the test above were plastic - DS-2 I think which I was expecting to perform far worse than it did. Unfortunately being a separate cased pump it is not easy to check dimensions like you can with an in-block type.





You can see into the pump through the outlet and view a 40mm x 20mm section of the impeller - and that's it - you can see some clearances but just when you think you have understood the critical clearances looking into this little window as to what makes a good pump, put your reputation and your Strato's project on the line, and stated it to be the worst of the bunch due to its plastic impeller and canyon wide clearances, it performs third best ! You just cannot see enough to make any sort of judgement. Although the best pump had the very smallest visual tolerance between case and impeller - you cannot measure diameters or view any differences in vanes etc.

The good pump needs to come apart to have new seals fitted so we will be able to take all the critical measurements to find out why it performs the way it does.

Interesting. I've had problems with idle-speed coolant flow in my X1/9 for quite some time. I've chased down loads of issues with various bits of the cooling, but I seem to remember it worked fine before swapping the original pump as it had dead bearings.

I wonder if the replacement pumps I've got just aren't as good as the original ones. Might try and find a NoS one...

So,

bizzo sent me a few pictures and I think the problem is this bit here.





I was not expecting it to look like that as I thought that at some time in the past 'x' years the T-Stat housing was turned 180 degrees so that it pointed down and in the opposite direction. Well it's now in the standard Imp orientation and is staying there so we need to install a bleed line back to the header tank.

A bit of fabrication - Lathe, bead roller, Drill, TIG and we have








It will be fitted and tested on Wednesday.

Now that is an interesting item. I had been looking at Ford V6 pumps, they are for the most part a separate pump, pretty cheap and look to need simple fabricated connection. Also for any other complete separate pump, I had not given thought to a standard pump and a fabricated housing so that is a very interesting item. I will have to inspect the X-Flow block that is on a stand at bizzo 's place tomorrow evening to see how it form any volute.

More than enough flow to keep 100BHP+ cool

Thanks norfolkginetta that is another direction to explore.

norfolkginetta

Sent you an email and a PM

I would need to measure the X-Flow standard pulley and compare to the Imp Standard pulley - the race engine will rev to 9K + typically the deep groove alloy race crank pulley is enough - However, I also have a super high RPM crank pulley !! I think the alternator would only charge at 3000 RPM with that one.