MADJAK's NA8 - 200+HP N/A

[DanZig]

Awesome work! Looks super neat, well designed and made to a high standard. Look forward to hearing your full review.

[mrpham]

Very cool and thanks for sharing!

This solution will definitely help me out with my ITBs filtration setup. How is the pedal effort compared to factory booster?

[speed]

Another custom work of art. Function AND form.

[SileNceR]

Damn this makes a good noise

[madjak]

I'm not sure I have actually posted these videos in my thread... turn up the sound

Dyno run


Idling - That exhaust stings!

[DanZig]

Sounds awesome! Very jealous of that idle, I want it in my life.

[rascal]

Sounds awesome! Very jealous of that idle, I want it in my life.

Just buy some adj cam gears and add heaps of overlap to your current cams, and it will sound similar....

[madjak]

The brakes worked great. I was a little cautious on them early in the event but go more confident as the day went on. It took me a while to get used to hitting them harder initially, and then later in the day I was getting more brake and dropped too much speed into each corner. They are definitely quicker, once I get used to them.

Here is my run for the day. I was a second off my fastest time but I didn't get a chance to get settled in the car. You can see the delta time from my Race Capture showing I was 1.4 seconds up a the end of the Esses, but lost most of that due to a slow corner speed down the back of the track and then too much brake at the end of the main straight.

[The Green Goblin]

What an animal, sounds awesome & I bet would be so fun to drive.

[madjak]

At my last track event I broke the tps connector that links the sensor to the throttle plate. It's a common issue with the skunk2 throttle bodies as the little connector is held on by a tiny screw. Completely inadequate! Not only that but the throttle plate is sloppy and the spring is too soft. There is probably a goid reason they have the nickname Junk2.

So I figured I'd look for a nicer throttle body and googling online I found most the Honda guys use the 70mm s90 billet throttle bodies. By good luck there was one for sale on gumtree at a wrecker for only $100, and even better it had a oem tps and map sensor. Thats a great deal and give me spares of the sensors which is handy.

This throttle body is just beautifully made. All machined out of a solid block of ally and is super light. The connectors to the tps are nice and strong and everything is tight.

[madjak]

It's been a while since I updated this thread.

As part of my suspension / drivetrain upgrade I've been sorting out the 26 year old hubs. I repacked the front hub with Amsoil 2000 Dominator race grease and I've purchased new bearings for the rear. To those that say you can't do rear hubs in a garage, I managed to do it fine with a big socket and hammer. Once the bearings were out of the hub, I decided to take off some of the machined castings... 30 mins later I'd taken 300 grams off the hub!



Old hubs weighed in at 3047 and 3075 grams. The lightened ones ended up being 2740 and 2810. I could have taken more off but I didn't want to risk weakening them. Basically I have removed all the excess castings, and tapered the outer edge where the step is machined for the heat shroud. I don't run a heat shroud so it was all excess metal.

As part of this, I cracked the inner races out of the new bearings and replaced the grease in them to with the Amsoil. You have to be careful doing this as it is easy to damage the plastic ball carriers.

I then placed the hubs in the oven to heat for 15 mins @ 180 degrees, pulled them out and dropped in the bearings. Easy!


Who doesn't like the smell of freshly baked wheel hubs! mmmm


I haven't installed the inner CV seal yet and I think I won't bother. This car doesn't drive on the street so keeping out dirt isn't a major priority and the seal will only slow me down. My dad used to race without them given the limited kms of a race car and that the hubs get repacked more often.

Next project: Lightweight crank

[bruce]

Yum Yum.

[madjak]

Last night I noticed my rear sway bar bushings were looking fairly average. So I made up a couple of new mounts out of some square delrin stock I had.

They need a bit of a clean up but they should work better than the 26 year old rubber ones!

[rascal]

My next experiment is to try something new with my suspension bushings. I've never liked the idea of using Urethane as a bushing material as it can bind and needs to be greased constantly if you want to keep the suspension movement free. It is a nice and rigid material with some flex so I'm going to be only using it as a packer and making a slip bearing that fits inside the bushing for the suspension to rotate on. This is based on a user on MT.net that did the same idea but with bronze bearing.

I've ordered some 20mm bar stock of 4140 (Chrome Moly) that I'm going to drill and cut to length. Over this I'm going to be using some Igirdur bearings that will fit inside the existing Urethane bush. These are very cost effective at around $2 each. At each end I'll get some washers laser cut that will transfer the crush load of the concentric adjuster bolts onto the 4140 tube. The idea is that the inner sleeve and bearing slide over each other rather than the Urethane over the sleeve. I don't think the wear rate will be high given they are designed for use on earthmoving equipment etc.

Here is a quick 3D model of it:

Three months down the track, how are your awesome suspension bushings holding up?

Interested to do a similar thing, (even better if you are doing a group buy/run ) as just regreased my poly bushes and the difference is enormous.
But pulling the arms out and apart semi regularly to regrease isnt fun, and this looks like a way better solution.

[Magpie]

Rascal this is an option (been done to my suspension) http://949racing.com/installingzerkfittings.aspx or http://clubroadster.net/vb_forum/86-diy-how-writeups/49291-na-nb-zerk-fittings-when-installing-poly-bushings.html or http://rallyways.com/specialty/part-2-powerflex-poly-bushings-miata-installation/