e46 330 track car version 2 - Supercharger

[gchristofi]

Having lurked here for more years than I care to remember, thought I'd share the build of a function over form e46 330 track day car. I started modifying this in 2016 having sold a track focused e30 325 but wanting more power and faster lap times. (Still miss the fun e30 though!)

The car evolved over a couple of years with budget focused changes to suspension, steering, tyres, brakes and weight loss. Getting my hands dirty and recording the gains for specific mods was as rewarding as driving the car on circuit. If anyone's interested, the version 1 build is documented in a post on another forum:

http://www.e46zone.com/forum/topic/62849-budget-tr...

Sadly, that forum seems to have really lost a lot of traffic recently. After an 18 month pause for planning and research Version 2 of this car is now coming together , the second iteration centred around a supercharger install.

A lot of time was spent researching and pursuing the s54 upgrade route to more bhp but for a number of reasons I decided there was a better way to get what I wanted (Bar buying an M3, but I think I'll still be at half the cost of buying one of those and readying it for track)

Upgrades are:

- Active Autowerke level 2 Rotrex based supercharger with inter cooler and separate oil cooler

- Cat back stainless exhaust system (sounds great, but only on ramp so far)

- AEM wideband AFR fail safe gauge and Prosport 4 in 1 Oil pressure/Oil Temp/Boost gauge

- M3 anti fuel surge cup fitted in petrol tank

- Cooing system refresh with OEM radiator, pump, thermostat and hoses.

- Safety devices rear cage

- Welded 6 piece boot floor strengthening plates for rear sub frame (RACP)

- Corbeau Club Sport drivers seat with 6 point ex FIA harness

- Decided it was time for new rubber and this price (£230 full set!) was too good not to try some 265 35 18 Accelera Sport 651 R compound semi slicks... (Wonder how they'll compare to outgoing Federal 595-RSR). Worth a try and remember, more grip doesn't always mean more fun! ??

- Once all tested and proven, there may be paintwork too. That will have to wait for now as there's likely to be bumper / bonnet mods, arch extension / rolling etc required. As before, function over form is the plan.

Couldn't do all this work without first finding out how the engine was running. Went for a pre upgrades dyno a while back. Good news is that the engine retains all the power it left the factory with (m54b30 has a reputation for this) . Dyno is attached.

Any advice from those using FI on track or any other matter is more than welcome. Will post back once get the chance to complete the build and dyno again to measure the gains from the supercharger ??

Edited by gchristofi on Thursday 3rd October 23:30

[Andrew-b90y3]

Great to see that you’ve finally got a thread up and going on here mate!!

I’ve not been able to access e46zone for some time now so presumed it was no more!

Get some pictures up of you’re current progress on the car!!!

[gchristofi]

Andrew-b90y3 said:

Great to see that you’ve finally got a thread up and going on here mate!!

I’ve not been able to access e46zone for some time now so presumed it was no more!

Get some pictures up of you’re current progress on the car!!!

Hi Mate.... yes, at last managed to make some progress with this! Can't believe it's taken so long to get started! I'll post up some pics in a minute. I see you're progressing well with your project too. Look forward to hearing how you get on with those coilovers. If I can get mine reliable and under heat control on circuit then new suspension may be on the cards for me too. Would be interesting to get a comparison on dynamic ability of my cheapy coilovers versus yours. I suppose we'd need same tyres / anti roll bars etc for fair comparison though. Maybe see you on circuit 2020

[Butter Face]

Nice work so far mate, what power are you hoping for? I think the kit you’re looking at uses the C38 charger?

[gchristofi]

Gratuitous photos .......

Pre s/c dyno on Maha LPS 3000


Rotrex c38-81 supercharger


Standard engine bay prior to conversion (minus secondary air pump)


Test fit supercharger and bracket and first placement of intercooler. Much easier with cooling system out of the way.


Charge piping was a challenge. Finding space to fit pipes from the s/c output into the inter cooler and then back through the same space (or lack of) for pipes from the inter cooler to the intake was an iterative and frustrating process. With no inter cooler, this would have been a much simpler install.



Spark plugs were updated..


Higher flowing injectors installed (same rating as M3 I believe)


New cooling system including the thermostat housing and water pump with metal impeller were fitted


Routing of the new serpentine / supercharger drive belt.. retained the air con for now, may be removed if cooling is an issue.


Oil cooler for supercharger oil / traction fluid... this system has it's own supply.


The old exhaust system is one piece from the down pipes to the tips and weights in at a heafty 45kg. New stainless system need some modification for the early manifolds in my car but netted a 20kg saving.. nice!


First attempt at modifying the SE bumper to accomodate the changes. Needs some tidying and some mesh grills adding but very happy that I managed to retain the stock brake cooling ducts, even if they're at a slight angle.

[gchristofi]

Butter Face said:

Nice work so far mate, what power are you hoping for? I think the kit you’re looking at uses the C38 charger?

HI Butter.... yes, c38-81... reassuringly chunky bit of kit to pick up. The kit is rated at around 400 bhp and 285 lbs ft with 10-11 psi. Not sure I'll get those numbers without manifold work but lucky to have an early car with no cats in the exhaust manifold. Also being pre facelift, the ecu can be flashed with a laptop so I can change tune files myself.

If I get somewhere near 350 bhp crank, I'll be very happy. As it's a track car, the idea of under tuning for longevity is quite appealing. I have tune files for both 98 and 95 RON fuel. Will be interesting to see what difference that makes. Long term I may just decide to run on 98 RON fuel with the 95 RON tune to be safe.

[gchristofi]

Finished the conversion a few weeks ago (although still need to wire in the gauges). Put a few hundred road miles in and got the chance to revisit the dyno a few weeks ago and very happy with the results.

Power has gone from 229 bhp to 374 bhp (+145 bhp, +63%.)

Torque from 228 lbft / 309 Nm to 324 lbft / 440 Nm (+131 Nm, +42%)

This has surpassed my targets but perhaps better then the headline numbers is that the power delivery is very linear, no lag and perfect for track driving. Also nice to get a read on AFR whilst back on dyno and see the range being safe.

Here's the dyno plot with supercharger




And the same plot but showing before conversion and after

Edited by gchristofi on Wednesday 6th November 00:36

[Andrew-b90y3]

374 bhp is absolutely brilliant pal, that definitely makes all the hard work worth it!!

[gchristofi]

Andrew-b90y3 said:

374 bhp is absolutely brilliant pal, that definitely makes all the hard work worth it!!

Yeah, was well chuffed with that result. Intake Air temperature was beginning to creep up by the time we managed to complete a full run. We struggled with traction on the single roller dyno for quite a while which I suppose was a good sign. Won't really know if the cooling is up to par until visiting a circuit and looks like that won't' happen until next year now.

Plenty to do before that including fitting seats, harnesses, AFR gauge, Oil Pressure / Temp / Boost gauge. Plus of course plenty of road testing.

[Andrew-b90y3]

gchristofi said:

Yeah, was well chuffed with that result. Intake Air temperature was beginning to creep up by the time we managed to complete a full run. We struggled with traction on the single roller dyno for quite a while which I suppose was a good sign. Won't really know if the cooling is up to par until visiting a circuit and looks like that won't' happen until next year now.

Plenty to do before that including fitting seats, harnesses, AFR gauge, Oil Pressure / Temp / Boost gauge. Plus of course plenty of road testing.

Could the temp have been creeping because there was no natural airflow over the car as it was on a dyno?

What’s your next circuit going to be next year?

Get some more progress pictures put up!!!

[Andrew-b90y3]

Any more pictures of the exhaust OP? Pictures of it installed etc?

[gchristofi]

Andrew-b90y3 said:

Could the temp have been creeping because there was no natural airflow over the car as it was on a dyno?

What’s your next circuit going to be next year?

Get some more progress pictures put up!!!

I've sent you an email re the exhaust system and I'll post a few pics here too. Yes, the airflow on the dyno was probably not ideal and may have contributed to the creeping intake temps. Having said that, all I read about FI on track cars is that it's always removing heat that poses the biggest challenge. I'm fully expecting to have to remove a/c , change thermostat, fabricate some ducting and chop the bonnet in future but figure I'd start as is and track the benefit of any cooling changes moving forward. I'm rebuilding the CV on my propshaft at the moment (dismantled and assembled incorrectly and now fubar) so don't see me getting out until spring. Aiming for Snetterton in March with Opentrack once the dates are announced.

[gchristofi]

Andrew-b90y3 said:

Any more pictures of the exhaust OP? Pictures of it installed etc?

Photos of the exhaust are not great, but here's what I have....

First test fit without and modification of o2 bosses... back bumper will need some cutting to accommodate tailpipes I think but I'd already melted a lot of mine away at Silverstone a few years back.



flanges of the front box are level but if you have the earliest manifolds with staggered flanges on the downpipes you will need to cut and join the bits. (I think your 2002 will be ok though)


I "borrowed" the original down pipes and flanges and cut joined them to the new front box to make it fit correctly:



notched and clamped for a perfect fit just in front of the furthest forward fixing bracket and leaving space to weld in bosses for the downstream o2 sensors





This is were there was good space to fit the 5th Wideband o2 sensor for AFR gauge...

Edited by gchristofi on Saturday 23 November 23:31

[Chestrockwell]

Wow I bet that sounds bloody amazing!

[gchristofi]

Chestrockwell said:

Wow I bet that sounds bloody amazing!

It's great for a track car, feels quick the moment it starts.... not sure I'd live with it on a daily though....

[Tommie38]

Interesting! Any more pictures of the car/build?

Did you do anything with the compression ratio / would it be worth considering?

Also, are you able to give a ballpark cost for the kit?

Thanks for sharing.

[gchristofi]

Tommie38 said:

Interesting! Any more pictures of the car/build?

Did you do anything with the compression ratio / would it be worth considering?
Also, are you able to give a ballpark cost for the kit?
Thanks for sharing.

Loads more pics but since it's far from a show car and looks more like a family school run wagon probably nothing anyone would enjoy looking at.



The engine remains standard bar bigger injectors and the obvious plumbing changes and is apparently well proven oven many miles. Time will tell! The cost is directly comparable to an s54 swap I reckon. US/GBP exchange rates and import duties don't help at all but it's still cheaper to source from the US rather than the UK Europe. (can pm you details if you like?)

I took this route over the s54 swap for several reasons. Examples being it looked within my capability to DIY, needed very little wiring work. No coding of replacement ecus etc. And with early M54 management it's simple to apply vendor supplied tune files with a laptop. The biggest bonus over the s54 swap is avoiding the unknown issues that may come with a used engine on a pallet and the fact that you might find yourself having to double down on costs to start again if something catastrophic failed on the s54.

[Sf_Manta]

I've been considering supercharging to up the power on my 330i touring. How much faff is it to do and would it fit ok with a sports bumper setup per chance and if so, does it need any trimming?

Already running cams and a Alpina exhaust making 247bhp at the moment, and given these cams were developed for forced induction it should make for some intesting fun...

[gchristofi]

Sf_Manta said:

I've been considering supercharging to up the power on my 330i touring. How much faff is it to do and would it fit ok with a sports bumper setup per chance and if so, does it need any trimming?

Already running cams and a Alpina exhaust making 247bhp at the moment, and given these cams were developed for forced induction it should make for some intesting fun...

If you have a sorted car already and want M3 performance in a touring body then it's certainly worth considering. I spent way longer than expected installing the kit but most of the faff was routing the charge piping for the inter cooler and relocating a few things away from that area. If I had to do it again, it would be much quicker (isn't that always the way!). If you're not planning track usage, a non inter cooled kit may suffice and I reckon that could be fitted in a clear long weekend with a bit of planning.

Most kits I've seen have been used the sport bumper of M3 bumper. I reckon a non IC kit would just need a bit of shroud removal for the supercharger oil cooler and the IC kit may need a little more trimming but not excessively.

Be interesting to see what the cams/ exhaust could add :-)