"fisher" Mk2 Suction Pipe

[iamhe77]

So we have a coupe of M35's that have been highflowed and tuned with Haltech Interceptor or eManage Ultimate and a few highflowed but running a stock ECU - like mine.

With a 3" turbo back exhaust, it would seem that 200awkw at 19psi (?) was the limit. So we started looking at what could be restricting it.

I looked into the possibility of purchasing the TEPS suction pipe, as their design seemed totally logical and was a direct route from the airbox to the turbo as opposed to the excessive OE design which has 3 bends and 3 different pipe sizes as well as a resonator. I, and a few others held the opinion that the intake was a restrictive factor and part of the reason that 200awkw could not be surpassed.

During this time, "Scotty nm35" decided that making a suction pipe was the only way forward for his car.

(You can find his first attempt HERE)

After a bit of discussion, we decided to make one up for my car as well.

Anyway, the first attempt with the "mk2" design started with the twisty bend from the turbo and, being aluminium, obviously required heat wrapping.

It also required gentle bends for easier airflow and the internal wall needed to be as smooth as possible, so a fair bit of sanding was done to ensure this was the case.

(so you think that C34 turbo's are in a tight spot? Also note that the a/c pipe needed to be bent out of the way - worrying while bending, but all good)

Next up, we decided to experiment a little. I wanted as little disruption to the aluminium with smaller silicone joiners than the Scotty's original design.

We also decided to try to implement the OE A/F sensor pipe so the air would be a straight as possible over the sensor. Thought being that this would aid idle and possible stall concerns.

With the angles worked out, this was basically what the result was (3 small silicone joiners, the OE A/F sensor pipe and a "lobster" bend where the breather pipe (and later the BOV return pipe - see issue #2) connect in.

Again, the internal wall needed to be as smooth as possible with the silicone joins as small as possible

Connected to bottom section and heat wrapped.

... and with the breather tube attached and the BOV return barb not yet hooked up.

Lastly was the bend from the airbox to the pipe... again, this required heat wrapping as it felt like a radiator top tank while it was bare aluminium but also needed to be removable to get the airbox out for panel filter cleaning. (note. Heat wrapping was re-done after this pic)

You can see the extension on the BOV return pipe in the above pic which allowed the lower half of the pipe to be maneuvered to connect with the barb on the intake pipe.

Not 100% necessary, but I much prefer it to flutter... and the wear that would have to cause on the turbo.

End result in a very, very dirty engine bay

Issues!

#1 the first issue with the design was that the suction pipe, being aluminium, the size it is (76mm) and so close to the exhaust manifold, would get too hot to touch. Couldn't be good having the turbo sucking in scorchingly-hot air.... Hence all the heat wrapping.

#2 found that the OE BOV cannot be left venting to atmosphere. this leads to MASSIVE fuel consumption (4.3km/L over 2 days with mostly freeway driving) and also stalling problems when pulling up to an intersection. So I blocked it off which ended both problems but gave the car some very loud "flutter" and a pug that kept being ejected from the BOV pipe and stiting next to the turbo... which meant instant stall, and required fishing out.... which meant some very burned fingers

Benefits!

#1 Noticeable ease in which the car accelerates and builds revs (even with the OE dump pipe still on).

#2 More power. Definitely more power.

#2 Whilst the car does use more fuel when accelerating at a decent rate, economy has increased considerably. Particularly whilst cruising!

A/F ratio changes when the stock ECU finished it's "re-lean" period and is now 14.5, which is what most tuners aim for I am told.

So all up I am very, VERY happy.

My car makes power much more easily, I have MUCH better fuel economy thus far (will continue to test as the batch of fuel may have had something to do with it), not noisy (which is a plus for me), and my car no longer makes that annoying "wwWO!" sound that it did before, which I was told happened when the turbo doesn't get enough air and was the same sound as when GTR's such their intake pipe shut.

MASSIVE thanks to "Scotty nm35" who put in a TON of time and 99.999999% of the work

Maybe you should price it up for others mate.....

Edited November 16, 2009 by iamhe77

[andy65b]

great work guys. I love the innovation.

Watching for the kit....

Cheers

Andy

[iamhe77]

Kit would be a bit trickier.

Problem being that mine and Scott's turbo's are indexed differently to both the OE and each others!....so going off ours will probably not fit other M35's...

[Daleo]

Well done guys! You've definitely done the hard yards! Looks brilliant

Did somebody say Group Buy? Put me down.

[Daleo]

Kit would be a bit trickier.

Problem being that mine and Scott's turbo's are indexed differently to both the OE and each others!....so going off ours will probably not fit other M35's...

Damn, you posted this while I was excitedly typing!

If Scotty nm35 was interested, maybe it could be supplied with the turbo flange not welded on, clocked in, marked and finished welded by the fabricator of the purchasers choice? A single weld like that, would only be a small expense.

Just a thought.

[iamhe77]

Damn, you posted this while I was excitedly typing!

If Scotty nm35 was interested, maybe it could be supplied with the turbo flange not welded on, clocked in, marked and finished welded by the fabricator of the purchasers choice? A single weld like that, would only be a small expense.

Just a thought.

True. The difficulty is with the angles and the (very) limited space.

Even with my car there, it was difficult getting the correct angles... even when we did have the correct angles, the middle section moved slightly when the bottom clamp was done up!

Pain. In. The. Arse.

Having said that, if there is enough interest....

(not dobbing you in for anything Scotty )

[zei20l]

im interested

looks the good guys, very nice work! looks like there are several projects going on. i wish i had more time on my hands. over the xmas break ill be up to no good methinks

[scotty nm35]

I dont even remember you taking so many pics Cam.

I can definitely make more, although I am just a lowly backyard fabricator. There is a full 2 days work involved for each, which blows the cost out a bit.

No dyno run yet but there is definitely more poke, so it looks like the 200awkw limit may have gone. I will post up a graph of before and after fitting this week hopefully.

[iamhe77]

I forgot you were going to upgrade to the "mk2" design... or will you be improving the design it be a mk3?

Also wanted to post a pic with the stock intake lying on the ground next to the "fisher" intake... just to give people on here an idea of the difference between the two.

Think you could do it while you have yours out?

Got a few other pics, but I felt they were not required

Edited November 16, 2009 by iamhe77

[scotty nm35]

Stockie and Mk 1 intake. I had an idle airflow meter issue with this one as it didn't use the standard airflow tube, and the meter was mounted on the bend.

Cam's intake had no such issues once the blow off valve was plumbed back in.

[iamhe77]

Thanks mate.

Quick update on economy.

Just filled up today with a week of around town driving (including daily hills for those curious Sydney owners and quite a number of "test" launches ).

62.84L

558kms on the odo

= 8.9km/L OR 11.3L/100kms

Will see what the highway economy is like when I get a couple of hours to go for a cruise.

Edited November 17, 2009 by iamhe77

[Angus Smart]

What was your mileage like before the mod?

400-500km's per tank?

[iamhe77]

What was your mileage like before the mod?

400-500km's per tank?

Same day-to-day travel was ~520-540 and always around 70L to fill.

[Angus Smart]

i have a really heavy foot

[iamhe77]

i have a really heavy foot

Then you will feel the difference more so than seeing at the pump.

[pixel8r]

So all this is without any aftermarket ecu? you say the factory computer did this all by itself? I am shocked. I always thought that once you put an exhaust/turbo on etc that the factory computer would never be able to deliver good results...(due to the factory tune being so specifically customised to the standard setup) - I am glad to be proven wrong

So just by opening up the intake a little more you've achieved both more power and more fuel economy...I love it

[iamhe77]

Yes, yes, no.

Yes I am only running the standard ECU.

Yes, it did this all by itself

No, we did not open the intake a little. The hard pipe to the turbo is massively restrictive and going from a rectangular inlet of roughly 40x20mm (let alone the bottom bend) to a 76mm diameter pipe is a fair increase and one that we thought might play havoc with the A/F mixtures.

And yes, Steve. I love it too!

(and was probably more surprised than anyone )

Edited November 17, 2009 by iamhe77

[scotty nm35]

The 80mm Mk 3 intake works fantastic, no stalling or mixture issues. Now to find some funds for a dyno run.

Cost me around $300 in materials and 2 full days. Each one is uniquely fitted so if anyone wants one they will have to drop the car to me, I cant fit off my car as it means mine is off the road for 2 days. (unless somebody has a spare motor lying around I can work off.)

Edited November 23, 2009 by scotty nm35

[iamhe77]

Wrapping it mate?

[Angus Smart]

Yo scotty look into doughnuts made from alloy. will save you alot of time.

should be able to get one to fit that radius