Trumpet heat reducing gasket
Discussion
Chimp871 said:
I very much doubt they will do anything but reduce a bit of heat soak when the engine has been turned offDiscopotatoes said:
I very much doubt they will do anything but reduce a bit of heat soak when the engine has been turned off
Agreed. The plenum is supposed to take heat away from the top of the engine and doesn't this risk stunting that.
I've asked engine builders and it was laughed out the door but some people say they've had better running using one of these.
I would'nt bother personally.
The points about air volume are only really applicable at full revs as far as I can see so not actually a problem in reality,,, if I've understood the sales gumgh correct!
People get confused thinking a bigger plenum allows a bigger air reserve, but its on the wrong side of the butterfly to act as a reservoir- think about it- the plenum is normally in a negative pressure state like in inlet manifold, and the moment you snap open the throttle you have to fill the plenum before the air before it reaches the engine.
Anything you can do to reduce heat soak on the plenum is a good thing Alun, for this reason I'm surprised nylon wasn't chosen over aluminium for the blended base offered by Kits & Classics?
PTFE, PEEK, Ultem, Torlon, PPS all offer excellent thermal insulation qualities.
Its also worth noting that these days something like a raised blended plenum base would represent a very straightforward 3D print job, 3D printing cost are falling by the day so taking this manufacturing approach may even offer a cost saving to the consumer?
A polymer material like PTFE, PEEK, Ultem, Torlon or PPS would certainly offer a far superior thermal barrier than aluminium, if it also made the product cheaper it would definitely be a win win.
Personally I think it's only a mater of time before we see a complete 3D printed plenum with provision to bolt on the cost effective throttle bodies available in the States, from there it doesn't take a big leap of imagination to imagine the time when we'll see a 3D printed complete inlet system.
Clearly the market for Rover V8 tuning products is small making production runs equally small, this means economies of scale can really never kick in as they do with SBC or LS tuning paarts, the big advantage of 3D printing is once the file is created you can do super low volume runs at very reasonable cost.
3D printing is extremely exciting technology that will revolutionise the way we approach many things, as scanning becomes easier and printing costs come down 3D printing is sure to become the biggest development in small production fabrication we have ever seen, this can only benefit the car restoration world and the availability/price of Rover V8 tuning components too.
And it doesn't stop with nylon either, recently I've seen two demonstrations that will take 3D printing to a new universe of possibilities.
The first was a 3D printer that used casting sand as it's print medium, from there low volume cylinder head casting is just a trip to the foundry away. Actually there's no trip required, just email the file to a foundry equipped with a 3D sand printer and wait for them to send you your new cast aluminium performance Rover V8 heads.
The second demonstration will likely almost immediately make the casting sand printer redundant before it's even got started, how about 3D printing directly in metal? I'd say this technology is definitely coming if it wasn't for the fact it's here already
The possibilities are limitless, exciting times ahead indeed
https://www.youtube.com/watch?v=gqKYKRDQNac
PTFE, PEEK, Ultem, Torlon, PPS all offer excellent thermal insulation qualities.
Its also worth noting that these days something like a raised blended plenum base would represent a very straightforward 3D print job, 3D printing cost are falling by the day so taking this manufacturing approach may even offer a cost saving to the consumer?
A polymer material like PTFE, PEEK, Ultem, Torlon or PPS would certainly offer a far superior thermal barrier than aluminium, if it also made the product cheaper it would definitely be a win win.
Personally I think it's only a mater of time before we see a complete 3D printed plenum with provision to bolt on the cost effective throttle bodies available in the States, from there it doesn't take a big leap of imagination to imagine the time when we'll see a 3D printed complete inlet system.
Clearly the market for Rover V8 tuning products is small making production runs equally small, this means economies of scale can really never kick in as they do with SBC or LS tuning paarts, the big advantage of 3D printing is once the file is created you can do super low volume runs at very reasonable cost.
3D printing is extremely exciting technology that will revolutionise the way we approach many things, as scanning becomes easier and printing costs come down 3D printing is sure to become the biggest development in small production fabrication we have ever seen, this can only benefit the car restoration world and the availability/price of Rover V8 tuning components too.
And it doesn't stop with nylon either, recently I've seen two demonstrations that will take 3D printing to a new universe of possibilities.
The first was a 3D printer that used casting sand as it's print medium, from there low volume cylinder head casting is just a trip to the foundry away. Actually there's no trip required, just email the file to a foundry equipped with a 3D sand printer and wait for them to send you your new cast aluminium performance Rover V8 heads.
The second demonstration will likely almost immediately make the casting sand printer redundant before it's even got started, how about 3D printing directly in metal? I'd say this technology is definitely coming if it wasn't for the fact it's here already
The possibilities are limitless, exciting times ahead indeed
https://www.youtube.com/watch?v=gqKYKRDQNac
ClassicChimaera said:
I thought it was part of the design that excessive heat from the heads is dissipated through the inlet manifold and ultimately the plenum, mine gets very hot.
So if you stop the heat going upto the plenum with a thermal break ( spacer) where does the heat go?
Exactly, and how much heat is going to be transferred into the oncoming air (N/A) it's negligible I'd say. FI can double the AIT so the gasket is worthless apart from being a good airtight sealSo if you stop the heat going upto the plenum with a thermal break ( spacer) where does the heat go?
blitzracing said:
People get confused thinking a bigger plenum allows a bigger air reserve, but its on the wrong side of the butterfly to act as a reservoir- think about it- the plenum is normally in a negative pressure state like in inlet manifold, and the moment you snap open the throttle you have to fill the plenum before the air before it reaches the engine.
Boosted LS1 said:
If the plenum was designed to shed heat it would have been finned in a similar way to an air cooled motorbike. Coolant is the medium that's designed to take heat away. A cooler plenum would be desirable though.
So it's not designed to take heat soak ? I'm sure I've read somewhere it's supposed to aid that but then there's plenty running on carbs and FI so maybe it's a red herring!
For peeps like me who have kept the long 38 mm trumpets the extra space at the top might be of some benefit mind you.
Edited by ClassicChimaera on Sunday 19th March 15:03
I fitted the SC-Power plenum spacer, insulator gasket and bell mouth trumpets some 7.5 years ago when I was Chimpaholic.
http://www.pistonheads.com/gassing/topic.asp?t=764...
I fitted these components long before I switched to the Canems engine management system and they definitely helped improve my Chimaera's drivability on the 14CUX & distributor, the parts are still fitted to this day and I have no intention of removing them.
Oh and the best way to reduce heat soak is to reduce the heat the engine makes in the first place, and the best way to do that is change idle ignition timing from Range Rover's emission driven 12 degrees to what the engine really wants at idle which is 22 degrees...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Get shot of all the cats too
http://www.pistonheads.com/gassing/topic.asp?t=764...
I fitted these components long before I switched to the Canems engine management system and they definitely helped improve my Chimaera's drivability on the 14CUX & distributor, the parts are still fitted to this day and I have no intention of removing them.
Oh and the best way to reduce heat soak is to reduce the heat the engine makes in the first place, and the best way to do that is change idle ignition timing from Range Rover's emission driven 12 degrees to what the engine really wants at idle which is 22 degrees...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Get shot of all the cats too
Heat soak preventers such as are being talked about here are for girls. OK, if you spend hours sitting in traffic then there may be some benefit. But why on God's earth would you do that...
Men who drive like men go fast enough that air going into the engine goes in so quick it doesn't get the opportunity to 'warm up' in the plenum... Take beastie for example... beastie sucks air in like Linda Lovelace used to.. er... anyway, beastie consumes air faster than the Enterprise can make the jump to hyperspace.. or the Millenium Falcon can do the Kessel run... and we're talking parsecs here, like between planets... not minutes sitting on the M25 near Heathrow...
So get a grip people, thermal barrier my ar*e....
Thankyou for listening....
Men who drive like men go fast enough that air going into the engine goes in so quick it doesn't get the opportunity to 'warm up' in the plenum... Take beastie for example... beastie sucks air in like Linda Lovelace used to.. er... anyway, beastie consumes air faster than the Enterprise can make the jump to hyperspace.. or the Millenium Falcon can do the Kessel run... and we're talking parsecs here, like between planets... not minutes sitting on the M25 near Heathrow...
So get a grip people, thermal barrier my ar*e....
Thankyou for listening....
ChilliWhizz said:
Heat soak preventers such as are being talked about here are for girls. OK, if you spend hours sitting in traffic then there may be some benefit. But why on God's earth would you do that...
Men who drive like men go fast enough that air going into the engine goes in so quick it doesn't get the opportunity to 'warm up' in the plenum... Take beastie for example... beastie sucks air in like Linda Lovelace used to.. er... anyway, beastie consumes air faster than the Enterprise can make the jump to hyperspace.. or the Millenium Falcon can do the Kessel run... and we're talking parsecs here, like between planets... not minutes sitting on the M25 near Heathrow...
So get a grip people, thermal barrier my ar*e....
Thankyou for listening....
Kinda what I was trying to say. You certainly have a way with wordsMen who drive like men go fast enough that air going into the engine goes in so quick it doesn't get the opportunity to 'warm up' in the plenum... Take beastie for example... beastie sucks air in like Linda Lovelace used to.. er... anyway, beastie consumes air faster than the Enterprise can make the jump to hyperspace.. or the Millenium Falcon can do the Kessel run... and we're talking parsecs here, like between planets... not minutes sitting on the M25 near Heathrow...
So get a grip people, thermal barrier my ar*e....
Thankyou for listening....
ClassicChimaera said:
Boosted LS1 said:
If the plenum was designed to shed heat it would have been finned in a similar way to an air cooled motorbike. Coolant is the medium that's designed to take heat away. A cooler plenum would be desirable though.
So it's not designed to take heat soak ? I'm sure I've read somewhere it's supposed to aid that but then there's plenty running on carbs and FI so maybe it's a red herring!
For peeps like me who have kept the long 38 mm trumpets the extra space at the top might be of some benefit mind you.
Edited by ClassicChimaera on Sunday 19th March 15:03
ClassicChimaera said:
I thought it was part of the design that excessive heat from the heads is dissipated through the inlet manifold and ultimately the plenum, mine gets very hot.
So if you stop the heat going upto the plenum with a thermal break ( spacer) where does the heat go?
Cooling the heads Alun is the coolants job So if you stop the heat going upto the plenum with a thermal break ( spacer) where does the heat go?
the plenum may get hot in slow moving traffic idling etc but its not wicking away heat of any useful purpose IMO drive the car briskly pop the bonnet and then feel the plenum and you will find its barely luke warm (air cooled from through put int & ext) a point already made on the post already and just my cents worth 
only reason my spacer is still in place because I feel it gives the air more time to turn into the trumpet base mine being blended Edited by Sardonicus on Monday 20th March 09:52
Being a layman in all things mechanical and going by my internal thoughts,,,
Air speed is vital to force air into chambers, at high revs engines probably capable of drawing more air than the ports can handle so that's a limiting factor and not much you can do about it.
But at anything below say 4000 revs (guess)
Your relying on the engines ability to draw air, shortening or widening the trumpets will slow the speed this air can travel at when lower revs are applied so in fact you have less dense air and not rolling so well.
I'd also conclude from my logic
that the 38 mm trumpets are so close to the top of the plenum they are actually drawing in the air that's first and rapidly entering the plenum so a good air flow and take up ensues,,,
Ok this is not the way to ultimate Bhp but you maintain the engines ability to pull like a train at much lower revs, even on tracks, because the gearing isn't good you have to take many slow speed corners in 3rd gear so coming out of corners at lowish revs, Bhp ain't helping you here and that's where a good fast air flow at these low to mid revs will be more useful and faster. If you gain more hp and only loose a fraction of torque lost then I accept it will be ultimately faster.
I drive mine on the road like 95% of us so tune my car accordingly and Bhp has no worth to me. IMO obviously
As this is discussing a good companies product I can say I never fitted this because of the heat soak thing... I always wanted too!
I don't believe there would be any losses doing this especially coupled with the bell mouth trumpets, and if the heat (myth) has been dispelled then I'd be inclined to go for it.
As it is I run standard pistons and bores on 38 mm trumpets and standard plenum, get nigh on 29 mpg if the mood takes me and have 300 Bhp and 350 ft lb on tap,,, and doesn't shunt from 900 revs onwards,,, it would be quite something if these mods could make it even better especially at low revs!
It's hard to better perfection. But as all great racing drivers will point out "there's never the perfect lap" and you can always improve.
I might well try these one day.
Air speed is vital to force air into chambers, at high revs engines probably capable of drawing more air than the ports can handle so that's a limiting factor and not much you can do about it.
But at anything below say 4000 revs (guess)
Your relying on the engines ability to draw air, shortening or widening the trumpets will slow the speed this air can travel at when lower revs are applied so in fact you have less dense air and not rolling so well.
I'd also conclude from my logic
that the 38 mm trumpets are so close to the top of the plenum they are actually drawing in the air that's first and rapidly entering the plenum so a good air flow and take up ensues,,, Ok this is not the way to ultimate Bhp but you maintain the engines ability to pull like a train at much lower revs, even on tracks, because the gearing isn't good you have to take many slow speed corners in 3rd gear so coming out of corners at lowish revs, Bhp ain't helping you here and that's where a good fast air flow at these low to mid revs will be more useful and faster. If you gain more hp and only loose a fraction of torque lost then I accept it will be ultimately faster.
I drive mine on the road like 95% of us so tune my car accordingly and Bhp has no worth to me. IMO obviously
As this is discussing a good companies product I can say I never fitted this because of the heat soak thing... I always wanted too!
I don't believe there would be any losses doing this especially coupled with the bell mouth trumpets, and if the heat (myth) has been dispelled then I'd be inclined to go for it.
As it is I run standard pistons and bores on 38 mm trumpets and standard plenum, get nigh on 29 mpg if the mood takes me and have 300 Bhp and 350 ft lb on tap,,, and doesn't shunt from 900 revs onwards,,, it would be quite something if these mods could make it even better especially at low revs!
It's hard to better perfection. But as all great racing drivers will point out "there's never the perfect lap" and you can always improve.
I might well try these one day.
blitzracing said:
People get confused thinking a bigger plenum allows a bigger air reserve, but its on the wrong side of the butterfly to act as a reservoir- think about it- the plenum is normally in a negative pressure state like in inlet manifold, and the moment you snap open the throttle you have to fill the plenum before the air before it reaches the engine.
This the extra volume is the wrong side of throttle.Discopotatoes said:
ChilliWhizz said:
Heat soak preventers such as are being talked about here are for girls. OK, if you spend hours sitting in traffic then there may be some benefit. But why on God's earth would you do that...
Men who drive like men go fast enough that air going into the engine goes in so quick it doesn't get the opportunity to 'warm up' in the plenum... Take beastie for example... beastie sucks air in like Linda Lovelace used to.. er... anyway, beastie consumes air faster than the Enterprise can make the jump to hyperspace.. or the Millenium Falcon can do the Kessel run... and we're talking parsecs here, like between planets... not minutes sitting on the M25 near Heathrow...
So get a grip people, thermal barrier my ar*e....
Thankyou for listening....
Kinda what I was trying to say. You certainly have a way with wordsMen who drive like men go fast enough that air going into the engine goes in so quick it doesn't get the opportunity to 'warm up' in the plenum... Take beastie for example... beastie sucks air in like Linda Lovelace used to.. er... anyway, beastie consumes air faster than the Enterprise can make the jump to hyperspace.. or the Millenium Falcon can do the Kessel run... and we're talking parsecs here, like between planets... not minutes sitting on the M25 near Heathrow...
So get a grip people, thermal barrier my ar*e....
Thankyou for listening....
I agree and like the way he put's things. So, many get sucked into this marketed cheap hp b
ks. Those that say they can notice a difference are fooled by placebo me thinks.Message Board | Chimaera | Top of Page | What's New | My Stuff