Kato Kids BMW M3 powered 71' 240Z

[Riceburner]

I butchered my shifter, I needed a big offset and only used the lower knuckle of the RB shifter. The other %90 is L series stick.

[Fairlady Z]

awesome work Dave.

 

one of the most elaborate Zs around with quality in mind 200% at all times 

 

keep it up

[KatoKid]

Thanks everyone for the compliments, certainly helps keep the motivation up.

 

There was no way the factory BMW air filter assembly was going to fit so I had to find an alternative. Ended up with the only K&N filter in their range that had the required 92mm ID to match my MAF. Its pretty fugly and far from what I envisaged but it works and I'm constrained by the  oil cooler lines that run underneath. There's a bracket which you cant see that supports the MAF and filter coming off the engine mount below.

 

I thought of running a tube through the radiator support panel and having the filter out front in a set up like the standard 280 arrangement but the hole in the radiator support is way too small and I didn't want to cut it up.

 

[KatoKid]

Reality is that Ive always had one of these in mind but cost and fitment will present challenges!

 

May end up going with an S bend tube that picks up air from under the radiator using a brake duct.

[620Z]

Dave another option would be to use the passenger side air hole next to the top corner of the radiator. Then simply don't have air to the passenger side. Those vents are pretty average anyway.

I actually blocked mine off last week and welded in a plate to mount my remote oil cooler in the front section along with the oil radiator. For your application you could widen the hole and route the air tube through that. This would get your filter in the front section for some cooler air.

Just an idea.

[PeterAllen]

David - I thought outside the round.

 

I'm presently using a rectangular filter as I initially planned on an OTR setup. I've changed now to something behind, but above the radiator. Still a work in progress but just raising with you the option of other filter profiles, plus aluminium shrouds or housings.

[KatoKid]

Thanks Peter, good suggestion. Im not happy with way it looks......the more I look at it the more Im sure I will change it.

 

That is great motivation!

[dat240z]

Reality is that Ive always had one of these in mind but cost and fitment will present challenges!

 

May end up going with an S bend tube that picks up air from under the radiator using a brake duct.

 

The carbon M Power one is an absolute artwork. You need that, your car and build deserve it... 8)

[KatoKid]

So, I haven't been completely idle but life and work just keeps getting in the way...I have been plugging away on the exhaust system.

 

As Ive stated previously the factory M3 exhaust system is a dual 2" system all the way and the aftermarket systems pretty much replicate this but go up to 2.25" all the way . Everything I read says that Bimmers drone like crazy with a large single and lose the signature Bimmer note if you go away from duals so I was pretty committed to staying with this format if I could make it fit..... with the condition that I had to have good ground clearance.

 

I didn't want to use chambered type mufflers so I need as much length and volume in the straight through designs as I could fit under the car and hope that will get me through rego and still sound good and be nice to drive....we shall see! Mick Bellinger in Tassie has been fantastic with advice and built a custom stainless mid pipe resonator and rear muffler to my plans. Resonator is as long as space would allow, there will be two 12" hotdogs under the diff and then into as large a rear muffler as possible with dual inlets merging internally into a single 3" outlet.

 

 

I bought a bunch of 304 mandrel bends, V bands, hangers and other stuff and got into it.

 

The factory headers are double 3 into 1's with the secondary pipe being 2". In order to be able to remove and refit the headers in the car I needed to have flanges as close to the end of the secondaries as possible, there was little room so V bands were the only way. Down stream from the V bands it goes straight into a 2" to 2.25" cone and then eventually via many bends and sections into the resonator.

 

The two bits of wood in the photos are there to position the resonator while I built the engine pipe(s) and they sit hard up on the chassis rail for the front one and the back one is spaced down the corresponding depth of the rail so the resonator sits level in the car.

 

After many hours of work I'm very happy with the engine pipes and the resonator fitment. Ground clearances is not compromised at all ....but things may get a bit warm inside the cabin as it is tucked up very high and close to the tunnel ...Peter Allen, I share your concerns about heat but clearance is something I cant live without...heat is...I hope.

 

 

 

[KatoKid]

I lashed out and bought Vibrant Performance V bands from Summit and very glad I did....very well made, full stainless (cheaper stuff isn't) and they have this really cool flip on flip off quick connect feature for the T bolt. I couldn't tell you how many times I have removed and refitted them in the process but it was heaps and they work brilliantly.

 

I borrowed a BOC Inverweld 140 http://www.twi-global.com/industrial-membership/industrial-members-showcase/products/boc-inverweld/ which is a small portable machine. Its really a stick welder but can be set up to use as a TIG however it has ZERO features (hand or foot amperage control, pre flow, post flow etc) that you normally find in a decent TIG. I had never TIGed before so figured I would tack it with this and have someone experienced finish weld but after a bit of mucking around and going down to 1.6mm tungsten's I found I could get a pretty decent weld from it so have decided to do it all myself. As long as you get very good joins with no gaps you can just fusion weld with no filler, most of the time I enjoy it but every now and then it gets a bit ugly but Ive learned heaps and pretty confident now.

 

[Cozza]

Always the perfectionist, system looks great. updates on this build have been missed.

Keep up the good work and keep the posts coming.

Mick

 

[Sirpent]

Read post above............ you always leave me lost for words David

[Gordo]

It does look the goods. Must be tight around the Diff area?

[Riceburner]

Looks great David, you've certainly packaged it well. The welds look pretty damn good too!

[620Z]

Wow Dave that looks fantastic. I can tell you heat will be an issue as it was for me when I tucked my duel exhause right up into the tunnel. Heat softened the tunnel plate material near my gear box mounts. This created vibration through the whole car so I hope you have reinforced it. Also if you are using standard rubbers in the smae area you will have more problems once they heat up. So change all to noelthane if you haven't already. Thirdly heat in the cabin. I am not sure about coating stainless steel in that coating but if you can do it. If not then you might have to look at heat wrap. No aircon and a hot floor don't make for a good combo. Also I placed about 10mm of sponge rubber through the entire floor of the Zed. This helped for sound and heat in to the cabin.

Just some ideas mate. Looking good though. 

[KatoKid]

Thanks guys, Ive always done exhausts in mild steel and stainless is a lot harder to work with but the end result I think will justify it.

 

Craig, all valid points. I'm pretty sure some heat wrap of some kind will be required but I will drive it a bit to see how I feel about it before going that way.

 

Gordo, it is tight under the diff but its also tight everywhere so no big deal. Ive tacked up the hotdogs and pretty happy with how they fit, they will cost me half an inch of ground clearance compared with the rest of the system but because they are virtually in the same arc as the rear wheels speed humps etc shouldn't be a problem.

[KatoKid]

Hot dogs and first hanger is completed.

 

As recommended by Mick Bellinger Ive used generic "Toyota" rubbers which use 10mm push on rods. Ive used cheap mild steel rods for the top rods that have been welded to my modified suspension/front diff mount cross member as they will be painted but had to spend $70 for 10x stainless rods for the lowers. Mounted at 45 degrees it relies on the weight of the system to keep things central. There is some lateral movement as expected but its not enough to be a problem (I think) given the tight tolerances (I'm working with half an inch as minimums) and they are nice and soft so hopefully should provide good NVH insulation.

 

Its not easy to see but there is a step down from the exit of the resonator to the inlet of the hot dogs, required to optimize the ground clearance for the resonator and the positioning of the hots dogs to clear the R200 diff. Also required was the turned in exits from the hot dogs to clear the the rear suspension. The step down loses me some about half an inch of ground clearance but cant be avoided.

 

The mate I borrowed the TIG from needs it back for a few days....so nothing else till late this week.

[garvice]

Looking good David. Bet you can't remember how you ever worked on a car without a hoist.

[PB260Z]

Very nice work, and a great feeling of satisfaction from doing it yourself.

 

 

[KatoKid]

Looking good David. Bet you can't remember how you ever worked on a car without a hoist.

 

With you Brad....just saw the update on your 1600 on PF....yehaa!

[KatoKid]

Exhaust is virtually finished, just need to make the front mount for the rear muffler and do the O2 bungs.

 

Its been a much bigger job than I anticipated. Making it a dual system makes it much harder because you have to mirror everything ...if its a single system there is no reference so it always looks right but as soon as you introduce a dual system you can see where things diverge or converge or don't match and look pox if you don't take the time, especially so for this rear section.

 

If I was doing this again I would do it in mild steel and coat it, stainless is just that much harder to work with. The welding bit is fine its the cutting and fine tweaking to get a no gap join so that you can fusion weld is the really time consuming part as stainless is so much tougher (hardness) than mild.

 

Anyway I'm pretty pleased with the way it looks....just hope it is quiet enough and sounds good!

[KatoKid]

More of.....

[garvice]

Looks fantastic Dave. P.s. you have a problem

[NZeder]

Awesome as always David. Love your work.

[Riceburner]

Exhaust artwork Dave!

 

It's probably something you know already and it's a while off, but before you fire up the car with the exhaust on wipe it down with windex or prepsol. The oil from clean fingers/hands will leave marks that bake onto the stainless, I learnt the hard way with my headers.