Plenum spacers and insulator

[dog man]

Driving the car into London I've noticed it looses a bit of edge after some time moving slowly and in traffic, as I experience with most cars I've owned.

It occurred to me the other day that it's heat soak, that the inlet charge is being heated up somewhat. So I've researched the trumpet base insulator and that seems cool but what about the spacer? Opinions differ as far as I can tell.

Has anyone fitted it and had an improvement? (I know the spacer is not to do with heat soak) Also how about the bell mouth trumpets? (not in relation to heat soak but generally)

ACT do carbon trumpets too! all very confusing!

Anyway, I'd quite like to keep inlet related bits cool in town so I think the insulator gets the green light for me. I will also have a look into weather mine has the heated throttle plumbed in.

Edited by dog man on Thursday 21st July 17:03

[SILICONEKID340HP]

Magna Parva sell a 38mm thermal insulator which do not need longer bolts.A chap called 350MATT sells them he as a Griffith but only in 38mm .TVR power sell a thin insulator which i have fitted for £17.50 not sure if there any good !

[macdeb]

insulator plenum spacer

[JR]

macdeb said:

insulator plenum spacer

Why do you say that?

[LordGrover]

Matt's is nothing like 38mm thick. Can't speak for the others but I had his several years ago and from memory I'd guess 4-5mm.

[Alexdaredevilz]

LordGrover said:

Matt's is nothing like 38mm thick. Can't speak for the others but I had his several years ago and from memory I'd guess 4-5mm.

38mm would be the trumpet diameter

[LordGrover]

Ah, that makes more sense.
When the length of bolts was mentioned it implied (to me) the thickness.
As you were - nothing to see here.

[graeme4130]

How much power difference are we talking here ?
I must admit that I noticed the same though, just hadn't put much thought to it.
Maybe it's worth insulating the travelling air earlier too ?

[SILICONEKID340HP]

LordGrover said:

Matt's is nothing like 38mm thick. Can't speak for the others but I had his several years ago and from memory I'd guess 4-5mm.

Are you daft? i mean 38mm inlet.I would say they are the best on the market .Not sure about the very thin TVR POWER insulator .The very thick ones are more suited to the Range Rover type cars..sold on Fleabay with longer bolts.

[LordGrover]

[macdeb]

JR said:

macdeb said:

insulator plenum spacer

Why do you say that?

Hi Jonathon, long time no speak and hope you're well. I have an insulator and it 'seems' to try and do a decent job though I reckon in traffic it just delays the heat soak a bit. No good doing a ton and pulling over, open bonnet, hand on plenum to find it's cool as cars without will do that. As for the spacer, took car for a drive got back fitted spacer took for a drive got back took spacer off and put in bin. Seemed to 'bog down' when I floored throttle before picking up again. So, for me it made the performance/drive worse in my own little back2back test. Just my experience with it.
Also, isn't the extra volume of air the wrong side of the throttle?

[dog man]

Yeah I can see that the insulator would only delay heat soak - it gets so hot under there in traffic. Delaying it is good though, still seems worth it.

Sounds like the ACT smooth bore induction with heat reflecting wrap plus an insulator is about the best combination whilst keeping to a reasonable budget. Nice

[Alexdaredevilz]

How often do you need to give it large bananas at 6k rpm in London?