throttle bodies + airbox vs non airbox?

stevieturbo · Post by **stevieturbo** » Mon Jan 03, 2011 8:20 pm

Ian Anderson wrote:
stevieturbo wrote:I really cant see why anyone wouldnt want to run a proper air filter. It just doesnt make any sense ?
If you have gi=one to the trouble of going ITB presumably you are looking for best response etc

So why then would you want to put any restriction in the way?

IAn

Why do you think an air filter would be a restriction ? Size it properly and it wont be.

Ive never seen a proper race car like a Lemans, or F1 running with no air filter ?

In fact, the one's I did see at Prodrive for LeMans, used a surprisingly small flat panel K&N atop a carbon airbox

Ive seen bigger panel filters in some cars !! lol

kokkolanpoika · Post by **kokkolanpoika** » Mon Jan 03, 2011 9:04 pm

kiwicar wrote:I would go for 2 nice big air boxes, at least 10X cylinder volume each with a nice fresh air supply from outside and a big paper element air filter (twice the size installed in a similar output engine buy a car manufacturer ). But I like paper element filters because they do actually filter the air, that is why they are changed from time to time
Best regards
Mike

Do you mean 651cc x 10 = 6.5litre..

kiwicar · Post by **kiwicar** » Mon Jan 03, 2011 9:20 pm

Hi
yes 10X 651cc (actually I did not do the maths but I trust you

) as a rough rule of thumb, for 4 cylinders 10X individual cylinder volume, 6 cylinders about 13X cylinder volume, 8 cylinders 16X cylinder volume, these are minimium sizes and bigger is better. I would still use 2 airboxes as on throttle bodies the trumpets are a bit far apart to get a good shape to the airbox with only 16X cylinder volume.
Best regards
Mike

kokkolanpoika · Post by **kokkolanpoika** » Wed Jan 05, 2011 6:35 pm

Just spoke to my local Jenvey dealer, he has got 20y experience of building engines/has got own engine magnament system..

He say that his experience of socks are suck.. Some NA porsche V8 has got Jenvey throttle bodies + socks and they run it to dyno, with socks it will give approx 250hp and then they remove socks and fit 2x big panel filters and it will give 12hp more now. same results without filter.. He estimate that socks are too close to trumpets, and it will then limit air flow and deny venturi effect.

+ some Opel omega irmcher 4000cc it will give almost 40hp more without filters than socks..

I think it is not bossible?

With plenum, no straight increase form power. Only if engine soak hot air at full throttle, then there is possibility potential to increase power.. Usually engines witch has got inlet manifold and exchaust manifold at same side.. No straight effect at dyno runs when both are other side.

He recon to start 2big filters, easier/cheaper option. And plenum if inlet noise is too big, and if engine soak lot of hot air. And if go to plenum, 4" inlet pipe per side is minium..

+ Jenvey has got fibre glass plenum speicer to get more volume. And are quite cheap?

CastleMGBV8 · Post by **CastleMGBV8** » Fri Jan 07, 2011 7:16 pm

Timo,

I quite like the look of these and the price.

http://atpowershop.co.uk/catalog/dcoe-t ... 79fcb56743

Kevin.

topcatcustom · Post by **topcatcustom** » Fri Jan 07, 2011 7:44 pm

I did some work on the De Tomaso that Riverie made this for- managed to find pictures as it is exactly what I think you should have! Was fitted to a 427 Ford V8 with quad Weber 48's IIRC. Beautiful- has the filters inside so your cold air feeds go directly into the box without filters needed on the ends.