Birthday wish - Colder air!
Discussion
Well it is my birthday and along with all the cards (and many torches for some reason 
) I got a couple or parcels, one containing a length of heat reflective sleeve for my induction pipe and the other with a set of carbon fibre trumpets. Put these with the magna-parva isolator plate and I've got a fun afternoon under the bonnet!!
So once I've got all this kit fitted, it should give me a colder intake temperature and I could advance the timing, so how do I do it? advance the timing that is, I couldn't find anything about it in the bible.
Any help is greatly appreciated
Cheers
Rich
) I got a couple or parcels, one containing a length of heat reflective sleeve for my induction pipe and the other with a set of carbon fibre trumpets. Put these with the magna-parva isolator plate and I've got a fun afternoon under the bonnet!! So once I've got all this kit fitted, it should give me a colder intake temperature and I could advance the timing, so how do I do it? advance the timing that is, I couldn't find anything about it in the bible.
Any help is greatly appreciated
Cheers
Rich
Happy Birthday to you
The Trumpets will help but not convinced about the heat-reduction items - surely at the speed air enters the engine via the air filter, plenum and inlet manifold there is minimal opportunity for the air to be heated up as it passes through on it's way. The combustion chambers are obviously scorchio any way.
IMO The insulator between the trumpet base and inlet manifold may even make metters worse as it will prevent heat soaking from the engine through the plenum. Therefore the combustion chambers will be even hotter. IMO you need to take heat away from the source not prevent cooling.
Ricardo
The Trumpets will help but not convinced about the heat-reduction items - surely at the speed air enters the engine via the air filter, plenum and inlet manifold there is minimal opportunity for the air to be heated up as it passes through on it's way. The combustion chambers are obviously scorchio any way.
IMO The insulator between the trumpet base and inlet manifold may even make metters worse as it will prevent heat soaking from the engine through the plenum. Therefore the combustion chambers will be even hotter. IMO you need to take heat away from the source not prevent cooling.
Ricardo
Edited by ricardo bertone on Saturday 11th November 11:29
Edited by ricardo bertone on Saturday 11th November 11:31
ricardo bertone said:
IMO The insulator between the trumpet base and inlet manifold may even make metters worse as it will prevent heat soaking from the engine through the plenum. Therefore the combustion chambers will be even hotter. IMO you need to take heat away from the source not prevent cooling.
In practice the insulators have been found to be effective at reducing charge temperatures.
A lot of wise men used to think the earth was flat too - has it been properly proven that insulator plates make any real difference?
The length of time it takes cool air to travel from the air filter to the combustion chamber is very very short, fractions of a second - so I doubt that there is any real heat transfer from the plenum trumpets to the induction air.
Think about it - air being sucked in at say 100mph takes milliseconds to travel the 4 or 5 feet from front of car to combustion chamber.
Ricardo
The length of time it takes cool air to travel from the air filter to the combustion chamber is very very short, fractions of a second - so I doubt that there is any real heat transfer from the plenum trumpets to the induction air.
Think about it - air being sucked in at say 100mph takes milliseconds to travel the 4 or 5 feet from front of car to combustion chamber.
Ricardo
Edited by ricardo bertone on Saturday 11th November 23:04
Well I'm sure it can't harm if I fit one!
My thoughts on the matter is this; yes the air is traveling at a fair speed from the filter through my smooth intake pipe, though the AFM, around the 90 degree bend into the alloy plenum through the metal trumpets into the engine. All the time heating up due to friction and contact with substances (rubber air intake and alloy) that are being heated by the vast amount of heat generated under the bonnet.
If I can limit the amount of heat the air comes into contact with, it WILL be cooler as it enters the engine and therefore more dense, ergo gives a bigger bang.
Anyway...back to the question, does anybody know how to advance the ignition?
Rich
My thoughts on the matter is this; yes the air is traveling at a fair speed from the filter through my smooth intake pipe, though the AFM, around the 90 degree bend into the alloy plenum through the metal trumpets into the engine. All the time heating up due to friction and contact with substances (rubber air intake and alloy) that are being heated by the vast amount of heat generated under the bonnet.
If I can limit the amount of heat the air comes into contact with, it WILL be cooler as it enters the engine and therefore more dense, ergo gives a bigger bang.
Anyway...back to the question, does anybody know how to advance the ignition?
Rich
Leave the timing as is. It doesn't need changing to exploit the cooler air. The cooler air will be picked up by the air flow meter and the ECU will adapt accordingly. If you do want to change it, slacken off the dizzzy bolts and twist but advance it too much and the changes of melting a piston through pre-detonation are greatly increased.
Derbygreg those insulators on yank V8s are put there to stop fuel purculation when hot(have you tried running a car with this fault,its horrible)i understand Ricardo,s scepticism,we have all seen these claims of more H/Power from simple things like this,sure the top of the plenum will run cooler,but you will always get the heat raising from the lower part of the plenum where the trumpets are mounted contaminating the so cooled cooler air coming in via the b/fly past the top half of the plenum,Ok that heat from the lower is moving to slow to contaminate the air rushing in,for the same reason the cooler running top half is not going to influence the air charging in,you can imagine how much air these engines consume on large b/fly openings,i know every little bit helps but i think its to little to be worth while,i think where these cars pick up there air from in front of the rad is damn good anyways(cool air with a slight ram effect at high speed)well 100mph plus anyway.
Jools
Respect man - if you say it makes 2%-3% improvement that's good enough for me BUT -
- as an accepted 'oracle of all things TVR' why do you think it's makes an improvement - what's going on in the slightly cooler plenum to make such gains? I don't see how it can be the air temperature given the speed of the air sucked in - but I accept something else might be going on here - what is it?
Ricardo
Respect man - if you say it makes 2%-3% improvement that's good enough for me BUT -
- as an accepted 'oracle of all things TVR' why do you think it's makes an improvement - what's going on in the slightly cooler plenum to make such gains? I don't see how it can be the air temperature given the speed of the air sucked in - but I accept something else might be going on here - what is it?
Ricardo
shpub said:
Leave the timing as is. It doesn't need changing to exploit the cooler air. The cooler air will be picked up by the air flow meter and the ECU will adapt accordingly. If you do want to change it, slacken off the dizzzy bolts and twist but advance it too much and the changes of melting a piston through pre-detonation are greatly increased.
Thanks Steve, I'll leave the timing as is. I'll be getting a RR session to get the best of my set up as soon as I get everything fitted.
Cheers
Rich
that daddy said:
Derbygreg those insulators on yank V8s are put there to stop fuel purculation when hot(have you tried running a car with this fault,its horrible)i understand Ricardo,s scepticism,we have all seen these claims of more H/Power from simple things like this,sure the top of the plenum will run cooler,but you will always get the heat raising from the lower part of the plenum where the trumpets are mounted contaminating the so cooled cooler air coming in via the b/fly past the top half of the plenum,Ok that heat from the lower is moving to slow to contaminate the air rushing in,for the same reason the cooler running top half is not going to influence the air charging in,you can imagine how much air these engines consume on large b/fly openings,i know every little bit helps but i think its to little to be worth while,i think where these cars pick up there air from in front of the rad is damn good anyways(cool air with a slight ram effect at high speed)well 100mph plus anyway.
The insulator goes under the whole plenum, not just the top... i also think that mounting the intake pipe MMs away from a VERY hot preCAT somewhat detracts from the cold ait feed. Try touching your intake pipe after a few mins in traffic!
so I'll have to wait until the roads clear a bit 
Gassing Station | Chimaera | Top of Page | What's New | My Stuff