lamb_daiquiri wrote:
Ultimately cold air is more dense and more will go in. The trade off is cold fuel hitting a cold port wall will coagulate and pool. Air and fuel need to be mixed to burn. High RPM and high flow velocities will pick it up again as fast air is lower pressure and helps revapourise the fuel as the partial pressure it experiences is lower and the turbulence will help pick it up from the wall.

Carbs with cold walled manifolds also have poor transient response. A good thing to read to understand this is reading about X-tau acceleration enritchment on the megasquirt website.

clyons8 wrote:
Hmm just buy a whole other A12 that runs, when you start buying carbs and thermostats and all that jazz plus paying for a mechanic to do it all then you might as well just buy a running A12 that RUNS.

Otherwise stop pissing about and shove a sensor up the tail pipe or get the thing to a shop that will dyno it and know what they are doing, the good old rolling road is very useful. The great thing about a Datsun is that they are cheap to run, but they are only cheap when they work and they can get just as expensive as any other 4cyl modern engine when they need to be repaired by a professional.

old-tin get a link up for this thread that you're on about.

And if you disagree with the previous comments with such objection then explain and clarify the errors and let us know what your theory is behind why Isuzu, Subaru, Nissan and Datsun (Mazda, Mitsu?) find it necessary to preheat the inlet manifold either via water/coolant circuit and or exhaust platform.

Look forward to hearing about it all because it appears I too have had it all wrong.

Dodgeman wrote:
Quote:

old-tin wrote:
there is a discussion about your post on the morris forum feel free to check it out.
it's not so much your idea's on cooling thay are valid, but your interpretation of fuel and air behaviour is #OOPS#.

i could do a 1/2 page on your errors but i would hate to offended you with all my spelling mistakes. best you investegate how fuel vaporizes(-atomizes:)as it enters the engine and can infact do a 90deg turn without a heated manifold, as thay are for EMISSIONS

Well don't be shy, send me your half page of corrections as an e-mail & feel free to leave a link to the Morris website as I would dearly love to see what is being written behind my back.

Even now this very subject is being discussed in the current edition of "Flight Safety Australia" [May-June 2011, issue 80] the aviation industry publication on air safety & aircraft maintainance.

Try page 24, the article is called "A Chill in the Air" & it deals principally with carburettor ice & its causes. It also describes the conditions that I described in my post. The aviation solution to this problem is "carburettor heat" where hot air is fed to the inlet of the carb while the automotive industry went for "hot spot" manifold heat, which was replaced by water heating of the inlet manifold, then hot air induction was added to make a near perfect package.
quote]

well as a seasoned mechanic you would now that there is a big difference between an aircrarft doing 200mph in -20deg c and a motor car at sealevel(never hered of iced up jets in australia not even full on race boats), and the fact that you try to use that as verification is hilarious. im by no means trying to offend you but compleatly disagree with your interpretation on fuel atomization(not vaporization) and when i get time i will send you an email

have a nice day

ddgonzal wrote:
Back in the 1920s and 1930s they were heating the intake charge for better atomization, and that certainly was not for emissions.

Dodgeman wrote:
Quote:

old-tin wrote:
wow Dodgeman i actually feel dumber having read that misinformed load of monky[monkey] spunk.
are you shour[sure] that your[you're] not the mechanic raping his wolet[wallet].

Perhaps you could point out, in dot point form, each & every error in my post, along with the correct reply that I should have written & we can all be enriched by your giant intelect.
Learning to spell will lift our view of your educational standard & will help with your credibility.

Thomen

I have your e-mail & have replied.

I have always heard that a too big radiator will cause this. And if you have a 9 liter radiator when A12 stock is 4.5 liters, perhaps that is the problem. If your engine is running too cold