Turbo vs. SC for Track
 

I am looking at buying a car to use primarily as track car (road course not dragsteip) and a weekend rider. E46 M3s are really coming down in price and its currently at the top of my list.

I recently had to get out of my 135i and into a e90 328 as my daily driver to support my growing family. I have now been given the green light to get a 3rd car to support my car habit. I am in no rush (likely spring 2013) so I am going through the fun process of gathering as much information as possible on different platforms.

I have been lurking these forums for quite sometime, soaking up the great information on these forums with the advancements made on FI solutions for the E46 M3.

I will want more power out of the M3 (should I go this route) but I want to ensure the power delivery is smooth and favors a road track setup. All that said, would you go turbo (looking at HPF stage 2) or a higher end blower setup like the AA or ESS solutions.

Would love your thoughts.

You are going to find a split on the answers. It used to be all about super chargers and linear power being the only form of FI that is best for HPDE.

Now, with the advent of high compression builds, smaller, but powerful, fast spooling turbos, and even QUICK SPOOL VALVES, that turbo charged cars are just as controllable around the track as any super charger. And faster too!
64mm turbo, 10:1 compression, E85 fuel, and even a quick spool valve if you can fit one in, would be a screamer of a track car. You would likely smoke most other similar cars with Super chargers.

That is my opinion. You will find many who prefer the super charger. The slower guys!

Just look at HPF's turbo masterpiece of a track car...the Orange Beast!
You dont need that level of power to do extremely well around the track.
Stage one with E85, 64mm or a 6766, 10:1 pistons and the icing would be a quick spool valve!! The fun level would be off the chart!

Super Chargers only give you max HP right at the very end of the rev limit. A TURBO, on the other hand will give you a lot of HP for more of your RPM range, and a lot more torque. SC's with few exceptions dont make a whole lot of torque. There are exceptions. Euro-JAWS company is doing some great things with high HP and torque Super Chargers. Super Chargers are getting more powerful all the time. I still would go turbo.

If you get a system that spools up fast, real fast, then the power delivery will be as smooth as your foot can apply the throttle.

BTW, a tuner at AA told me point blank that their Stage 2 was prone to heat soak and over heating if pushed VERY hard on the track. He went on to say their best track set up was the Stage 1.5 which isn't all that fast compared to any turbo set up.

Supercharger...unless you want to spend 100k on a purpose built race car then turbo as far as the S54 powered cars go...the N54/N55's seem to have a better powerband for the track.

Agree, the N54/55 have the powerband but boy do they overheat. I could not run more then 10 mins at a time on the track with my 135i before the oil temps went through the roof. I would consider getting back into the N54 but would have to invest in supplemental oil cooling at a minimum along with power and handling adders. Besides, I have alwys wanted an M car :)

I am not looking at a purpose built car, I am looking for a car with solid power that will be a real joy on the track. I do admit, I would likely get power envy knowing I left something on the table with a blower setup. Thanks for the feedback I do appreciate it.

This is excellent feedback, appreciate it. Only issue I see is the E85 is not readily available here in Toronto, hence the desire to go stage 2 with meth. I would also like to retain stock internals, I really do not have a huge desire for a built motor.

You dont need a built motor for a track car. And unfortunately you cant use meth on an HPF kit on a track according to Chris. Gas or race gas only. Plenty power with race gas but it is expensive.

You have to be hard core to use E85 if you live in Canada. One member here from Toronto just drove 12 hours and filled up six 55 gallon drums with E85. It really helps your spool. And too bad. You can get the VERY BASIC Stage one HPF and walk out with 630HP on a stock motor.

What the other guys are saying about going the Blower route makes perfect sense too. It was all correct information. That may be best for you. But you asked what we (I) would chose. It would be a quick spooling turbo.

The ideal situation would be for you to EXPERIENCE both a quick spooling turbo and a Super Charger on a track and make your own choice. I was told over and over I would like a super charger better. I bought one and didnt like it at all really. Too wimpy, and quite boring. Some guys LOVE their SC'd track cars and would not trade them for the world. It comes down to personal preference really.

It is going to cost a lot more $$ to make a turbo track car than a SC'd one if money is an issue. If you DO decide to go turbo, try and get a Quick Spool valve installed by Sound Performance on a 67 or 64mm turbo. As long as the builder knows that the car is going to be tracked, he can design and build a very tractable turbo track car. Not too long ago, that was not the case.

I never stopped kicking myself for getting a super charger when I could have had SO much more power (power=FUN) with a turbo.

hmmm... I am looking 2 buy 2 s/c kits for the m3's soon. Guess I take a Look at ESS and VF...

-Trip

You cany easily use meth on a track car. Just have the on off switch in the steering wheel. Turn it on for the straights.

Sent from my PG86100 using Bimmer App

I was shocked beyond belief when Barry from AA told me that. I questioned him a good bit about what he said. There was no mistake. The one thing you must realize is the level of effort necessary to make the kit overheat is arbitrary. These guys do One Lap America and are close to being full on racers. A typical HPDE might not be enough to make the stage 2 overheat.
I would try and find out more from more typical club type members experiences.

Just the same, I would still be looking at ESS first if I was going to get a Super Charger. They seem to be able to supply owners with higher power options too.

Do they still offer that 620 HP monster(on a built motor, of course)for the E46? The VT-3?

http://forum.e46fanatics.com/showthread.php?t=696222

Too bad JAWS is so far away...in Sweden. Those kits are cutting edge for SC's!

Chris has posted many times not to use meth on the track, but he was likely meaning continuously.

I always wondered about using it intermittently, just how you suggest....sort of like a NOS button. The fuel map has to change too? Does race plus meth have its own fuel map, separate from race gas alone?? Can maps be swapped back and forth instantaneously? If so, it all should work great.

Yes, that makes sense to me. I dont see why that would not be OK.
Thank you for the clarification.

I stand corrected.

have you looked into getting another 135i and adding the Vishnu single turbo kit? high 500 whp (no need for meth or race gas to make that power either), with a small, quick spooling turbo, a fat torque band that pulls till redline and costs a little more than half of what even a stage 1 HPF kit costs and makes plenty more power than that. i don't believe Shiv has installed one on a 1 series yet but the 3 series kits have already proven themselves to be an enormous bang for the buck mod and still able to live with as a daily driver. might be worth at least looking into.

So what will happen if you use meth on the corners?

thanks

Chris, the owner of HPF claims that the meth injection system when used continuously in a track setting will overheat and malfunction somehow. He was not specific. But he has stated this on several occasions.

I am sure if you ask him specifics he would tell you.

It is surmised that brief sprays of meth (using a demand button) just on the straights will not cause the system to overheat.

daemonicus, I really like your idea. Vishnu makes pretty nice kits. They seem pretty reliable. I bet the one series would be a track monster with that turbo set up.
It is at least worth looking into of the OP already has a one series.

do you guys think the s54 can hold up to the power the turbo makes for 10+ track events a year? also, the excess strain that the turbo puts on the car by the excess power it makes stresses the frame and overall components of the car much more than if it were n/a

do you all agree? i believe that to run the hpf kit on the track is possible, however, it will cost much more to maintain the car overall.

Tune is different but yes it changes instantly. I think chris was getting at the fact if you use meth all the time on the track you cause alot of methanol movement in the tank and once lower youll start picking up air bubbles etc ive used full tanks of meth before in one sitting on the hw just constantly doing pulls back to back. Didnt break or overheat the pump, those pumps or used in other industries non stop for hours


Sent from my PG86100 using Bimmer App

as far as meth usage at the track goes, most sessions last 25 mins.....majority of that times is under full throttle, that meth tank will be empty in like 10 mins or less, it will possibly run dry and then need to be purged.....also the nozzle could overheat and then flow the incorrect ammount thereby running lean

the is absolutley no reason to run meth at the track, 450whp is more than enough power for the track.....try making your car lighter and handle better, that will increase your lap times more than anything

As I recall, it wasnt the pump that Chris was concerned about, it was the nozzle overheating like mentioned in the above post.

If you run race gas, or better yet, E-85, there really isnt a need for meth at the track at all. You will have so much power you will be more concerned in saving your tires!

I really never liked the idea of a whole separate tank to keep track of anyway. I used to burn right through my tanks when I had a SC'er.
That is another benefit to E85(yes, sorry to those who just don't have access to it)....no meth needed.

In almost all cases, I recommend and prefer a turbo setup. With a supercharger, you are always limited power-wise by the pulley setup and are hampered by the boost you can run. You also have the progressive-linear curve of boost that is frustrating if you need power on demand. Most people think that you have all the power available immediately with a blower but that's not the case most of the time.

With a turbo, there's a seemingly never-ending level of power at your fingertips (assuming you have the engine management and supporting mods to handle it). If you run out of boost, you can jump up to the next size turbo (without going too large for road racing of course). However, for the BMW and with options like the 6266, 6466, and 6766 CEA, it would be very hard to not find the right setup for you.

In the end, how you use the power is what's most important on the road course. This is coming from a guy who road races a GT42 Supra with a Quick Spool Valve which is incredible effective.

Reid

The biggest problem you have to deal with is heat. No matter what kit you buy you will have to do some work to the cooling system on the car. The big one would be a stiff fan clutch and a lower temp thermostat. Along with those I would get rid of all the coolant you have and switch to straight water and water wetter. Make sure you have an undertray on the car that isn't broken and maybe look in to a little ducting around the radiator and intercooler to make sure you're getting the most possible air to flow across both. I too would prefer the stage 1.5 setup on the track over the level 2. Not to say the level 2 won't last in on the track, but you have to think about the extra fatigue on all parts of the drivetrain. A headache free car is way more fun than one with tons of power sitting in your garage waiting for parts.

After a level 1.5 kit I would worry more about what kind of tires you're going to run each time at the track rather than how much power you have. :D

Want to see what a turbo M3 does at the track, click http://www.youtube.com/hpfchris

There are quite a few track videos in there.

Chris.