TRUMPETS

[Ballistic Banana]

on the 500 are they proper ones or the bits of straight pipe, or is it the usual TVR lottery

I have got the Silicon air hose pipe, wass prehaps looking at changing teh Trumpets if they are the straight ones, and also going the Jag airflow meter.

Also for my winter list to do:

Hammerite and Waxoyle
Re-trim hard section of roof
Makes some outrigger guards
Make a Alternator heat deflector.
Battery - block Earth wire.

BB

[Pies]

Unless your very lucky its drain pipe

[Ballistic Banana]

Was unsure as whether that was on the S's and early Griffs

BB

[GreenV8S]

Never tried it myself, but in theory I guess you should be able to see them if you shine a torch through the throttle body? Failing that, it's a relatively quick job to take the plenum chamber off.

[19560]

Ballistic Banana said:

Hammerite and Waxoyle

Better to use epoxy mastic www.rust.co.uk

[2 sheds]

all 500's left the factory with the straight (slightly tapered)44mm i/d steel tubes with no roll at the top, all other engine sizes used standard rover 38mm trumpets which had a small amount of roll at the top.
After market upgrades are very common so there are plenty of cars around with larger trumpets.
Tim

[starmist]

You could do worse than an ACt trumpet base with either steel or carbon (better shape) trumpets. Don't know about the jag afm, but the Bosch one is good, but won't work with the std chip - you'll need an MA Tornado chip.

POR15 is much better than Hammerite and you won't need the Waxoyl which looks crap.

[griffter]

starmist said:

POR15 is much better than Hammerite and you won't need the Waxoyl which looks crap.

It's worth spraying with waxoyl the bits you can't paint though.

[Painey]

Out of curiosity, how much difference does fitting new trumpets make?

By this I mean, I'm considering modifying my Griff in the new year with new ACT hose's from air filter to plenum, new Bosch Air Flow Meter, new Bosch injectors, tornado chip and then having Mark Adams set it all up at Austec. Would getting the trumpets done make much of a difference on top of what I'm already planning??

Thanks - Chris

[2 sheds]

During a "back to back" test at V8 Developments dyno trumpets alone made 9 lb ft at peak torque, not all engines are the same so i would say between 5 & 10 lb ft
Tim

[Steve_T]

Pretty much the same setup as you describe gained me roughly 35bhp - would tell you if I had the dyno sheet. The car also pulls through to 6k (never did before) and is still as easy to drive as before. Its a good first step and most of the increase is down to the injectors. If the bill doesn't scare you then it's worth doing.

Steve.

>> Edited by Steve_T on Friday 19th November 19:06

[only me]

Had the Bosch injectors and air flow meter and the Mark Adams Tornado chip and the rolling road at Austec with Mr Adams and Paul and it made a HUGE difference. as Steve t said it pulls like a train all the way round to 6k is noticeably smoother throughout range and my biggest gain was in torque which is know around 340. Done it mainly to solve a pinking problem but what a overall difference it has made would recommend it didn't do the trumpets maybe next year ot there is always xmas!

Dear Santa .......

[v8 racing]

ok so i am a mate of tim from act so it probably sounds a bit bias BUT FIGURES SPEAK FOR THEM SELVES! the goodies you can now purchase from act are well worth the money you spend and more, i built a 5.3 engine with an enlarged plenum which made x bhp recently fitted with act's trumpets and triple plenum and is now making x times a massive increase!! like about 70 ftlb!! bhp per pound????

[starmist]

I wouldn't have thought it was worth paying £600+ for the injectors unless you are doing mods to get more air into the engine, such as larger / more throttle bodies and a cam that allows the throttles to get that air into the cylinders. Even with an ACT twin and R404 (Tiny) the standard injectors were just about coping!

[v8 racing]

tiny your the man!! absolutely right! for once the voice of correctness, there is a lot to be learned about these engines {SORRY MY SECRETS ARE MINE AND STAYING WITH ME!!} but tiny is dead right the vodoo or black magic or whatever you want to call it is nothing more than getting that air into the cylinders, ypu can throw a 'speicial cam' 'big heads' injectors that flow the missisipi river and a whole bunch of over stuff at your motor but if it ain't getting the air in you may as well give your missus the money to buy on shoes

[GreenV8S]

This is second hand and you'd be better off hearing it direct from the exports, but I gather the Bosch injectors give a better spray pattern/give better atomisation/are luckier than the standard ones/whatever, and this on its own can produce more power, even if the original injectors weren't maxed out. There have been reports here on PH where changing the injectors alone has gained over 10 bhp, and that's well worth £600 in my book.

[starmist]

They do have a better spray pattern, and are built to closer tolerances than the standard Lucus jobs. You can run lower fule pressure whihc also gives a better spray, therefore better atomisation and a better, faster burn.

[tvr4ever]

Ok, here we go. On the subject of trumpets, can someone explain a few things to me.

Are all the trumpets of a 4.3 the same shape / hight ?

Are the ACT trumpets a different shape ?

Could one make trumpets himself if you're realy handy ?

A mate of mine is a wizzard with metal, if I could show him a trumpet the way it should look, for maximum performance I mean, he could make me a set from a blok of aluminium.

Is this a mad idea, I mean could this be done, or am I crazy in thinking I could have a set of homemade trumpets for little money ?

If the idea is not as mad as it sounds, does someone have a trumpet to spare wich I could show my mate.

Thoughts and suggestions please.

Cheers,

Fred

[ballistic banana]

tvr4ever said:

does someone have a trumpet to spare wich I could show my mate. Thoughts and suggestions please. Cheers, Fred

sorry its the only spare one I have

BB

[ballistic banana]

Think they are different shapes as you have to cut bits of the top of the trumpet to get them to fit under the Plenum and aggainst each other.

BB