Trumpets - Whats the deal

[Jon Brown]

After reading a few threads on here I was thinking about trimming the trumpets down a little on my 400.

Is there much point/gain to this?

If so how much do i need to shorten them by and is this equally across all of them or certain ones?

My final question, i couldn't find a guide. Do they pull off and do they need to be glued back into place?

Thanks

[blitzracing]

I removed 15mm from all of mine, the idea being to increase the air gap between the top of the trumpet and the plenum roof for better flow. Its also supposed to lift the RPM band peak torque occurs at, but I don't have any data to back this up. They pull out of you heat them with a blow torch to soften the glue and need to be glued back in with something like JB weld epoxy resin thats reasonably heat proof. They are quite thin so I had a plastic bung turned down to fit neatly inside so they could be clamped in a lathe. You could do it with a hacksaw and a fine blade, but it would be harder to get a smooth joint where it joins the trumpet base.

[Jon Brown]

Great thanks, maybe ill see if i can get another one before i butcher mine

[OleVix]

15mm on mine worked nicely, feels more eager all the way... If you have ported heads, big valves and a spiky cam, 20-25 mm would probably suit better for high revvyness!

[SILICONEKID350HP]

These short flared aluminum trumpets are cheap enough..

[ybt1982]

SILICONEKID350HP said:

These short flared aluminum trumpets are cheap enough..

I'm in the market for trumpets, details please

[SILICONEKID350HP]

ybt1982 said:

SILICONEKID350HP said:

These short flared aluminum trumpets are cheap enough..

I'm in the market for trumpets, details please

Contact Rob at V8D ,he may just sell you the trumpets alone .. Don`t forget the insulator gasket between the trumpet base and inlet manifold ,don`t go for one of those real thick one`s seen some on fleabay.

[MPoxon]

I have the ACT Trumpets and thermal gasket on mine, it certainly improved the torque.

http://www.actproducts.co.uk/shop/tvr-induction-tu...

[Alun450]

What's the length of the original trumpets again? And what's the length of the ACT ones please.

[SILICONEKID350HP]

Alun450 said:

What's the length of the original trumpets again? And what's the length of the ACT ones please.

You want short one`s, More HP and a bit less torque . It`s not a Range Rover.

[Alun450]

Chucke chuckle, yes but how long are the Landie ones! If you chop off what's already been chopped off?!!? As if but it would be interesting to know If the ACT are 15 mm shorter? Does the air flow through Carbon better than metal? Mine must be chopped off it's that fast. Lol

[SILICONEKID350HP]

Alun450 said:

Chucke chuckle, yes but how long are the Landie ones! If you chop off what's already been chopped off?!!? As if but it would be interesting to know If the ACT are 15 mm shorter? Does the air flow through Carbon better than metal? Mine must be chopped off it's that fast. Lol

The carbon fibre ones do not get hot so the idea is to have cool air going in to combustion chamber ..Don`t know if it is a gimmick but they do look nice ..

I has some on the 4l ,sold them when i went from 38mm to 45mm .for the 5l build.

[QBee]

Circumcise the trumpet section?
Car will end up sounding like the Jerusalem Colliery Brass Band.....

[Alun450]

Can I join them! 45mm bloody hell Daz that thing must rip, you must put cans on, are you going to Bedford? Gimmick. have you seen the exhaust the air passes by! Sounds true but hey! I gotta go to bed I'm picking up my grandson tomorrow and finding a track to sound test. Alun

[SILICONEKID350HP]

Alun450 said:

Can I join them! 45mm bloody hell Daz that thing must rip, you must put cans on, are you going to Bedford? Gimmick. have you seen the exhaust the air passes by! Sounds true but hey! I gotta go to bed I'm picking up my grandson tomorrow and finding a track to sound test. Alun

Don`t know if it helps the 450 but to make the 45mm trumpets work you need the port matched inlet manifold and the bored out 72mm plenum

[blitzracing]

Heres a picture of the stock ones vs 15mm reduced ones. They are different lengths (as standard) as to compensate for the different inlet tract lengths in casting below. These are only on the smaller engines, the 5ltr has large bits of unflared drain pipe fitted instead.

[Alun450]

Nice one. I saw a plenom Power bored out, can't bleeding remember the size! What is it with these cars, you make a list, tick it all off, then make another fking list to keep up.