How long are you trumpets? (silver top, zetec owners)

[John Williams (Panda) - Joint Manchester AO]

I looked at my jenvey TB trumpets over the weekend and thought they looked a little small, how big are yours?

 

In stuff and nonsense as i can image the responses.

[Norman Verona]

First question that comes to mind is who specified them. If it was the engine builder then they should be correct, if it was just "they look OK" they'll almost certainly be wrong. Trumpet length and exhaust header pipe lengths are a bit of a black art and experimenting with different lengths takes years to get the right combination.

 

NMS or Blink may know whats best. Email them and ask.

[RobC]

How long is the inlet manifold too...?

 

My manifold is about is about 100mm and the trumpets are 90mm.

 

But like norm says all depends on what's been done... If it was mapped with shorter ones adding 90mm may alter the spectrum. Just a thought anyway

[AidanPlace]

Mine are the same length they were when they were attached to the crossflow :-)

[Dave Eastwood (Gadgetman) - Club Chairman]

90mm is probably the most common length that Jenvey supply. Occasionally quite short ones are used for bonnet clearance issues, and a few people change to 120mm

 

Alternatively, get a set of the telescopic jobbies from Emerald, (assuming you have Jenvey parallel type TB's), get on a rolling road and work out what the right length is from there.

 

(As hinted at though, its the total length from the back of the valve all the way along to the end of the trumpet that's important.)

[dombanks]

i tell the mrs its not length its girth that matters... oh hang on wrong trumpet ... err.....

 

 

90mm for me on jenvey supplied throttle bodies and manifold on a silvertop zetec. i can measure exactly for you later each bit of you want.

[John Williams (Panda) - Joint Manchester AO]

i tell the mrs its not length its girth that matters... oh hang on wrong trumpet ... err.....

 

 

90mm for me on jenvey supplied throttle bodies and manifold on a silvertop zetec. i can measure exactly for you later each bit of you want.

please mine are like this

 

 

the reason for asking it i'm going to need a new filter; so should i have longer trumpets and come out of the bonnet

[Onliest Smeg David]

Without measuring yours look longer than mine John!

[Dave Eastwood (Gadgetman) - Club Chairman]

That looks like the short set up for bonnet clearance purposes.

 

I know a few 1.8 Zetec owners that have gone for the long option, including bonnet cut-out, (and light remap to suit) and been really, really pleased with the results.

 

Obviously, some of that will be down to length and some down to the bonnet cut out. (Cooler air).

 

The compromise, aesthetics aside, is that it will be louder with the trumpets sticking through the bonnet.

[John Williams (Panda) - Joint Manchester AO]

Thanks Dave,

 

Thats what i thought....

 

come on smeg you know you want to join the trumpet club

[Onliest Smeg David]

Thanks Dave,

 

Thats what i thought....

 

come on smeg you know you want to join the trumpet club

If it means more power and drivability it may be an upgrade sometime, it would involve a mapping session (Do you think Blink would do a two for one deal?   ) 

[Norman Verona]

John, the length is critical for best performance. Whilst drawing cool air from outside is desirable the best length is probably more important.

 

As usual cosmetics has nothing to do with it.