ITB Sound vs Carbs

MPoxon · Post by **MPoxon** » Sat Feb 09, 2013 5:22 pm

Afternoon all,

This sound a little strange but I have always been a bit disappointed with the sound of my Griff 500. Don't get me wrong the exhaust note is epic but it does not have any induction sound.

I had the pleasure of seeing Andy Race's Monster Griff a long time ago now and this had an incredible induction roar from the quad Delloroto carbs.... here is a vid of it in action.

http://www.youtube.com/watch?v=mNcvdPUvKdg&feature=related

I did look into fitting a 4.5 Tuscan racer spec engine in my Griff but after speaking with a number of experts I decided not to due to the amount of work involved in ditching the EFI system, dramatic drop in MPG and the fact it would never pass another MOT (1999 cat car).

A number of people did say why not fit ITBs instead. My question is to those of you who run a Rover V8 with ITBs - what does it sound like on full chat?

I was looking a possibly the John Eales Crossover manifold with Jenvey ITBs. I know a number of the Marcos boys have these.

Matthew

mgbv8 · Post by **mgbv8** » Sat Feb 09, 2013 10:31 pm

If the exhaust note is nice then folk wont hear the induction roar. Or are you saying that the induction sound is what you want to hear inside while driving it ?

stevieturbo · Post by **stevieturbo** » Sat Feb 09, 2013 11:41 pm

ITB's are a very expensive route to making some noise !!

If you had a fairly open intake tract with a non enclosed filter then it should already be pretty loud.

So what exactly is your current setup ?

MPoxon · Post by **MPoxon** » Sun Feb 10, 2013 1:04 am

mgbv8 wrote:If the exhaust note is nice then folk wont hear the induction roar. Or are you saying that the induction sound is what you want to hear inside while driving it ?

Yes exactly that, with old carb V8s you hear that lovely induction roar when you are inside along with the v8 burble from the back.

MPoxon · Post by **MPoxon** » Sun Feb 10, 2013 1:11 am

stevieturbo wrote:ITB's are a very expensive route to making some noise !!

If you had a fairly open intake tract with a non enclosed filter then it should already be pretty loud.

So what exactly is your current setup ?

At the moment it is standard Rover EFI cast plenum but with ACT carbon fibre trumpets inside, the big Bosch AFM, ACT hose down to the standard TVR air box with panel filter in the nose of the car.

At present there is no induction sound whatsoever. Any ideas that are cheaper than ITBs but without loosing too much power would be gratefully received.

stevieturbo · Post by **stevieturbo** » Sun Feb 10, 2013 9:49 am

The long inlet tract, aiflow meter and standard air filter are what makes it all quiet.

You cant cheapy get around the airflow meter, but I'm sure you could fit a free flowing K&N type filter closer to the throttle.

Eliot has a lot of variations on his website.

http://www.mez.co.uk/ms12.html

but if you check this out, this will give an idea that will make lots of noise. It wont need toe carbon lid to achieve it. Just a short airflow path to atmosphere and a free flowing filter.
You should be able to achieve something like that without breaking the bank.

http://www.actproducts.co.uk/induction/ ... omponents/

DaveEFI · Post by **DaveEFI** » Sun Feb 10, 2013 10:01 am

The Rover Vitesse inlet produces quite a bit of noise at high revs. Commented on in the original road tests.

MPoxon · Post by **MPoxon** » Sun Feb 10, 2013 10:36 am

Cheers for the advice gents I will try a K&N filter as close to the AFM as I can and see if that makes a difference.

DaveEFI · Post by **DaveEFI** » Sun Feb 10, 2013 10:40 am

MPoxon wrote:Cheers for the advice gents I will try a K&N filter as close to the AFM as I can and see if that makes a difference.

That usually moves the air intake from a cold place to a hot place. It also alters the tuned length on the inlet tract. Was quite noticeable when I tried it on my SD1, so I junked it.

ian.stewart · Post by **ian.stewart** » Sun Feb 10, 2013 1:09 pm

Well I suppose I am biased, I ran ITBs on my rover, and the noise was epic, I still get comments from people who used to see it around town telling me how good it sounded, and one comment that will stay with me, from a fella who is not known for his compliments, and a hotrodder who only had good words for hot rods, telling my mate as I left it was "the Hardest car he had ever heard", even my mate was shocked at that comment from him.

stevieturbo · Post by **stevieturbo** » Sun Feb 10, 2013 1:16 pm

There is no doubt they will sound fantastic.

But to spend several thousand quid just for a noise.....really really hard to justify, when it will still sound excellent with some cheap induction modifications.

MPoxon · Post by **MPoxon** » Sun Feb 10, 2013 5:41 pm

ian.stewart wrote:Well I suppose I am biased, I ran ITBs on my rover, and the noise was epic, I still get comments from people who used to see it around town telling me how good it sounded, and one comment that will stay with me, from a fella who is not known for his compliments, and a hotrodder who only had good words for hot rods, telling my mate as I left it was "the Hardest car he had ever heard", even my mate was shocked at that comment from him.

Now that does sound very interesting. I have heard some epic sounding RV8s running carbs but don't think I have ever heard an RV8 running ITBs. I would be interested to learn more about your Rover with ITBs. Do you have any specifications, pictures forum threads ?

ian.stewart · Post by **ian.stewart** » Tue Feb 12, 2013 9:45 am

I dont have a lot of pictures as they were lost with a computer failure,....
Engine spec was different from the norm- but did work, very well,
it was based on a JE early block relined to 3.9, Omega pistons, 13.8 comp ratio!! Injection HRC rods with ARP bolts,
Cam was a TWR grpA stock lift cam but with massive overlap and duration, ARP studded mains and heads, Heads were TVR challenge heads with roller rockers and lightweight Ti pushrods,(Just because I found them on EBay) Induction was TVR challenge split inlet manifolds and 45 Jenveys, all controlled by Emerald M3Dk ECU
Static compression ratio was high, but due to the type of cam there was a lot of bleed off, so the running (dynamic) compression was around 10.5:1, the added advantage of a low lift cam and has gentle ramps allows you to run softer valve springs but still doubles, less loading and friction, the engine revved like a bike rather than a Rover, I had a self imposed limit of 7k, but the engine did go to past 8k on a couple of occasions, output was around 305hp and 290 ft lbs on its last set-up after i fiddled with the cam timing, Exhaust manifolds were 1.3/4" tri-Y joining into one 2.5 pipe under the gearbox and into a single Flowmaster box right at the back of the car,
This vid is the only one I know of iot running, badly at the time due to a dodgy stretchey cam chain (cheap poop sold as top quality stuff) hence the bonnet being off trying to find the misfire still ran a 12, It later ran a 12.2 when fixed on street tires. sorry for the rubbish sound.
http://www.youtube.com/watch?feature=pl ... ta5Ke6Xrho

MPoxon · Post by **MPoxon** » Tue Feb 12, 2013 11:21 pm

Many thanks for the detailed information Ian, very interesting and a impressive spec.

I am fairly sure I have seen your old motor at Pod before. It certainly does not sound like any rover V8 I have ever heard.

Those ITBs do look the business.