Going To Play With Inlet Tract Length

[Mandic 0]

Is it possible that stock manis are not well tuned and if one wanted to extract gains from 2nd harmonics, manis would be just too long, so people opt for 3rd harmonics and they tune manifold lengths accordingly (cut them) ...

 

Cheers

 

Ziga

[cybernck 400 1 Cars]

no, people cut them to clear the radiator .

[Mandic 0]

ah well, You are right

 

besides, some of us don't have such problems and look from power point of view

 

Anyway, I'm a bit sceptical about all this harmonics mambo jumbo...

 

Cheers

 

Ziga

[Sandy 189]

I'm sceptical about a theory based on such a small proportion of the variables involved, being reliable.

[smckeown 1]

I have beeked 2 cheap power runs back at road and race powerformance mid nov, this wil lallow true back to back comparisons. I aim to take 2 new lengths with me to see the power/curve difference they make. I have received the new filters and have ordered the pipe lengths.

[smckeown 1]

Finally got the ali tubes and filters today

 

 

I have 2 sessions at the RR next weekend where I can compare with 2 new lengths of trumpet. The RR is the same as when I had the car originally setup. By the weekend it will also have the same map and cam so the results will be comparible.

 

Let's see what I can make this weekend then

[smckeown 1]

Wasn't able to finish them completely, so just the bases to sort out now. Here's today's progress:

 

Measuring current induction length and free space, not as much free space as i imagined to i'm looking for about 4cm increase which should take me from 330mm to 370mm in length:

 

 

I took the opportunity to have a look at the air flow to the trumpets as i noticed tt205 had cut his grill, as suspected the top of the grill is rather restrictive

 

 

So out came the saw..

 

 

Looking much better even with bonnet on:

 

 

The new 130mm trumpets so far:

 

[t16ryan 1]

nice looking good, interesting to see the outcome

[sonofsam 5]

What wall thickness is that tube then Sean?Bet a bit of I.D. polishing wouldn't go a miss;)

[Miles 331 1 Cars]

Are you going to flare the ends to bell mouths? and I would run both without filters as different types of filter makes a differacne to airflow as well

[smckeown 1]

Are you going to flare the ends to bell mouths? and I would run both without filters as different types of filter makes a differacne to airflow as well

 

In this version I won't have bell mouth's. As with TT205 i'm hoping for some gains with this setup, i'm hoping the filters are ok. The next stage (when i have more time over xmas), is to build a custom front entry airbox with a large flat panel filter; also with bell mouths on the trumpets. I'm just researching this now

[petert 550]

The next stage (when i have more time over xmas), is to build a custom front entry airbox with a large flat panel filter; also with bell mouths on the trumpets. I'm just researching this now

 

I've been playing around with this for some time. But trying to find a panel filter that's big enough and fits is near impossible. I've been cross referencing between the K&N site (filter by size) and the Green Cotton. I'll be keen to see how you go. As an interim, I've built a box with side entry fed by a cone.

[smckeown 1]

I've been playing around with this for some time. But trying to find a panel filter that's big enough and fits is near impossible. I've been cross referencing between the K&N site (filter by size) and the Green Cotton. I'll be keen to see how you go. As an interim, I've built a box with side entry fed by a cone.

 

You can get a green panel filter for a Lamborghini Countach that's 380mm x 150mm in size. I'd thought that is plenty

[welshpug 1,622]

something like this?

 

 

[smckeown 1]

i've just been out to measure and that ferarro one is too hight, it wont clear my lowered rad and fit under bonnet.

 

The Fiat Dino (Spider) 337 x 131 looks better....

 

Unless I can tilt it like the one in the pic above. Need to look more closely tomorrow

Edited November 11, 2006 by smckeown

[Miles 331 1 Cars]

Be intresting to see the result's, I know that the air flow with high and low pressure area's make's a differance, hense why I said about the bell mouth's which I'm sure make a differance on the radius too

[petert 550]

Trying to find one that would flow enough air (for 240+hp) and fit under the bonnet was the issue. The other issue was the minimum distance between the bellmouth and the panel. My research suggested 70mm. I'd be keen to hear the thoughts of others. Here's some that looked promising:

 

K&N

33-2504

33-2710

Edited November 12, 2006 by petert

[Sandy 189]

Have plain end pipes will influence the results, you get a stalled zone around the perimeter of the pipe entry which interrupts flow.

[smckeown 1]

Trying to find one that would flow enough air (for 240+hp) and fit under the bonnet was the issue. The other issue was the minimum distance between the bellmouth and the panel. My research suggested 70mm. I'd be keen to hear the thoughts of others. Here's some that looked promising:

 

K&N

33-2504

33-2710

 

Nice one pete, that 33-2710 which is 446 x 131 looks a good size.

[smckeown 1]

here's an update.

 

I have approx 80mm of space to play with, I might need to drop the rad another 10mm, we'll see..

 

 

I now think that retaining the existing sausage filter and making air horn spacers is the best / most economical way forward. This saves me buying a new panel filter and building an airbox.

 

This is a diagram of how the back plate / sausage filter would be retained in relation to the spacers, pretty fundamental really.

 

So I have all the materials here to make some spacers, i'll make 40mm and 20mm versions, which will allow me to test a tuned length increase of 20mm to 60mm

 

 

The benefits of this setup are:

* Minimse cost regarding air box and panel filter

* Get to keep the excellent existing 90mm bell mouth air horns pic here

* Have a system of playing with lengths bettween 20-60mm relatively easily

[Sandy 189]

Nice one

[sonofsam 5]

So does wall thickness play apart in this experiment? I guess you want the maximum quantity of air as you can in there? equally thinner walled gauge pipe.

[smckeown 1]

So does wall thickness play apart in this experiment? I guess you want the maximum quantity of air as you can in there? equally thinner walled gauge pipe.

 

eh ? surely as long as the ID is 45mm the spacer thickness makes no difference ?

[stew205 17]

Hi Sean,

 

I am nearing completion of my airbox. I have just popped outside and taken a coupe of pics for you. I will get some better pics in the light!

 

Space was a major problem, even more so due to running a cast block. The rad has been moved further forward, the alt. bracket changed...

 

I am pleased I have been able to use the 90mm trumpets which gave the best results during mapping.

 

 

 

 

 

 

 

 

Its getting there but not finished.

 

I will get some better pics up.

 

Thanks

Stew

[sonofsam 5]

eh ? surely as long as the ID is 45mm the spacer thickness makes no difference ?

 

Pardon. The reason your having difficulty finding 45 I.D. pipe is because it usually get's measured by O.D. and wall thickness

 

of course, i know away around this