RS Motorsport :: Classic Speed Restored

Has anybody drilled and taped new holes in a Redline manifold before?

I am looking to be able to insert a 1/4" NPT pressure transducer into each carby runner for various analysis and also to balance the carbies (playing around with the new Picoscope). I believe the water jacket surrounds each runner so I am not sure of this is easy/possible??? I have the water jacket blanked off so there is no coolant in there whilst running.

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Waterjacket surrounds each runner? That's news to me.
Measuring inletrunner-vacuum with an electronic pressuretransducer and picoscope will lead to nothing as pressure inside the runner varies all the time. You will need a bit of software that simulates a low-pass-filter (like 1 Hz) to dampen all these variations.

I'm not seeing water jacketed runners in that pic either.

You will need to weld a boss on each runner to get thread depth to seal against.

There is no water jackets around the runners and I wouldn't bother chasing your tail logging vacuum

Figured there was a water jacket seeing as there is a water inlet on the mounting face.

I had already thought about the variances in the vacuum signal (that is another analysis I want to do to see if I can read the pressure pulse going up and down) - the Picoscope allows the singnal to be averaged so all is good.

None of this may provide any useable info. It is just as much about playing and learning.....

If you are serious with datalogging fit some thermo-couples to each exhaustrunner and measure exhaustgas-temps.

Bingo, I'd be looking at exhaust temps before playing with the inlet manifold

I was going to measure exhaust back pressure and pulses.

Thermocouples are a great idea. Would they be better than a wideband O2 sensor on each header primary? Would be less wiring than an O2 setup.

I was also thinking of measuring the coolant pressure in the block in various places and also the temp to look at this whole plumbing the water pump back to #4 cylinder business....get some facts.

I have considered doing a full data logging project using an Arduino board just for giggles which would open the scope of measurement up (but I probably have enough kms of wiring in the car as it is!).

I believe exhaust temps would be far more useful than any inlet pulse/pressure logging. Logging the inlet side isn't going to give much useful info. And what can you do with the info anyway, and how will you act upon what you find?? maybe redesign your headers 20 ways??

And quite frankly, putting an O2 bung in each primary and giving it a good tune that way will yield a better tuning result. Exhaust temps can have quite a variance due to many factors that you have no control over, and will give you not much useful info you can do much with in a carby engine with a dizzy. An engine with an ecu and efi with many logged parameters will make much more use out of such info.

And if you really want to go faster, log the driver, not the car!

Keep us updated anyway mate

Hi,
inletvacuum and waterpressure can be measured but in my view it will lead to nothing.
You will sophisticated software to middle out all the peaks to get a reasonable reading.
Like on the vacuummeters you can get to measure inletvacuum, these are naturally damped by the coil of the meter plus the adjustable orifice of the vacuumline.
To learn about different temps of the block why not use those temperaturestrips?
A wideband O2 sensor in each exhaust-primary is overkill and might not work that well due to the fact the mixture (or exhaustgas) is not constant. Just fit one in the collector about 5 cm from where the primaries or secondaries join. If you log that signal plus the ignitiontiming of cyl. 1 you should see differences in mixturs between cylinders.
One of the most cost-effective tools I have is shown below.
You can measure (difference in) exhausttemps immediately so no guessing in what cylinder is doing something wrong. Also with some experience you can measure the temp of the inletrunner near the head and determine that the valveplay on a valve is different to the others because that temp is different. (combustiongases will go back into the inlet because of inletvalve being open with piston goin up).
Regards, Leon.

Got one of those . Very useful tool. You cannot use it to measure the temperature of various parts of the block/head as you are measuring the iron which gradually absorbs the heat and effectively averages it out. Might get a small variance - in the interest of fact and science I will try once the engine is back up and running. My zorst headers are ceramic coated which effects the readings although I assume it effects them evenly allowing meaningful conclusions to be drawn.

On many threads here people have claimed that having a thermostat in the engine will result in better cooling as it creates pressure within the engine causing coolant to circulate better. I have always thought that is claptrap so here is my chance to find out once and for all.

Inlet pressure measurement is primarily about balancing the carbs without using the length of hose claptrap. Any other analysis is just playtime.

How are you going to design your experiment to conclusively answer your thermostat question?

The block has a blanking plug in the side that could be used to measure the coolant pressure. 1. thermostat in 2. thermostat out. I could remove the temperature sender in teh head and replace that with another pressure transducer to read the head pressure also.

Oh just had a thought. The welsh plugs in teh side of the block will respond to temperature changes much quicker than teh surrounding iron block so could be used as a poiint for measuring coolant temperature i.e. do we need to plumb the pump to the back of the block or not...

Still working through a 25 point list of repairs and upgrades on the car so not at the point of writing my thesis!

How many temperature sensors?

In an ideal world I guess you would need one each end of the block and one each end of the head = 4 to get a good representation of what is happening. However, none of that will pick up on any isolated hot spots.

Given how passionate others have been in past threads, on this and other forums, about the need to plumb the pump to #4 I would assume others have already done this measurement!!? Think I read that Holbay did some research when they developed their ultra wierd water system.

Yes I recall that debate happening also. If it is sucking then the water enters the block then gets sucked out before circulating around #4 buts that's a different arguement for a different thread.

I use an EWP anyway so that doesn't apply to me.