Individual Throttle Bodies aka ITBs

[Dodo Bizar]

Ah ok. I got an Eagle manifold lying around actually. It is just a very tiny piece of aluminium with a vacuum chamber in it... I think around 10ml, 10 cm by 1 cm in size approximatly. You can connect up to 4 (or 5?) small vacuum lines and 2 medium vacuum lines both on a T-splitter.

Normally ITB's have 4 small vacuum lines as well on all 4 throttle bodies. So connect those to the vacuum manifold leaving out one empty small slot on this manifold. Do this by using small T-plitters or anything. The big vacuum hoses should be used for the brake-cyl and carter ventilation. Though the last one I am not sure if it is smart since oil could block the hoses easy. Perhaps do not connect carter ventilation at all and make a seperate circuit for it (needed/how?).

Put the map on the last available small slot. This is how I should do it, but never did it actually. I suspect all sound pulses would cancel out a little when reaching the MAP sensor so you should have some descent signal. I know in practise that most people end up using TPS mappings instead of MAP mappings since MAP signal is has too much pressure fluctuations on it. No idea how these people connect there vacuum manifold if any...

[novaksaotome]

actually making a vaccum reservoir was what i had in mind, so gettong the map installed shouldnt be that of an issue, i still have to finish the head side to be able to fix the itbs. still fighting with the wiring of my mini me tho... will keep you posted!

[saxophonias]

So , lpg and itbs!! What are the benefits in theory comparing to regular gas?

[hondamake]

I mentioned in the LPG thread about the high octane rating of propane, up to 115 depending upon mix (LPG is often a propane/butane cocktail with a few other hydrocarbons thrown in) and differing measuring standards. A combination of this fuel with the greater airflow of ITB's plus the ability to live map using your laptop - may give some interesting results. It may require a gas only strategy on a D14 because you would have to manually alter the ignition timing to make best use of the gas, if you then try running petrol you may well hole a piston. The early Rover/Buick V8 runs static timing of 12*btdc as standard but needs to be altered to 6*btdc to perform on gas. You could by a device to alter this automatically but they were expensive and seldom used, they may still be available. From memory it was called a Pick-Up 60? As ever the theories are simple, the devil is in the detail.