Making the M5 engine faster/more powerful. Is it NOT feasible?........... - The Unofficial BMW M5 Messageboard (m5board.com)

FAST 5 · 23rd April 2003, 19:26

Hello Guys,
I've been reading this board for a while now and to me it seems as though, aside from adding a BLOWER (which is something I will never do) onto the M5 motor, its not possible to get any significant horse power gains from the M5 engine. True?
Im not including the Dinan S2 package into this topic, because for me it is way to expensive of a modification and the claimed power gains are supposedely NOT there, as the claimed 470 HP by Dinan, it's been said to be more like 440's to 450 HP. So, for me the S2 package doesn't exist. Adding software chips don't do much, minimal at best, whether your dealing with POWER CHIPS or a DINAN software download. So aside from adding a setup such as the A.A. CAI system and a 3.45 rear diff mod (which doesn't really add horse power to the car) to the car, what can be done to juice up the M5's power ? I've always heard that the M5 engine is just about maxxed out, maybe it is true afterall!
Any thoughts or comments guys? Thank you.
Robert
PS Again, Im bringing up the topic of getting SIGNIFICANTLY MORE POWER from the M5 engine.

23rd April 2003, 20:15

Robert,
I think that your observations are correct. My opinion is that each individual upgrade assists in bringing the M5 towards the "More Power" goal. More power to me is not just measured RWHP, but also straight-line acceleration. The S2 package is very significant in the way it adds power and acceleration to the M5. I have driven both S2 and non-S2 M5s, and there is a night and day difference. My short list of things that must be done on the road to "More Power" are:

- 3.45 Differential.
- Throttle Bodies.
- Velocity Stacks.
- Headers.
- Exhaust.
- CAI.
- Lightweight wheels.
- Lightweight flywheel.
- Reducing weight by 200+ lbs.
- Short-shifter.

Having the above, will make you happy with the M5's power; I speak from experience with how much of a difference the above makes.

Cheers.

Lupo///M5 · 23rd April 2003, 20:52

I have to agree as well. Tuners throughout the world haven't been able to get more than 40-50 HP out of the S62 engine. Not AC, not Hamann, not Nowack, and not Dinan. RMS is the only way to add HP, but the consequences of this have yet to arise.

I believe we have to accept what we have, enjoy the brilliance of the S62, and drive one of the best cars ever made. After all these years, car manufactures are still using our beast as a bench mark, and to me that sends a bigger message than more horsepower.

mweel · 23rd April 2003, 21:13

I;ve given up for some time trying to make the M5 faster.

The only provable options I have seen is NOS and the Supercharger. Not options for me yet.

I would rather concentrate on the things that the M5 lacks - suspension, gearing, breaking, sound, etc..

//MWEELS

TriflowM5+M3 · 23rd April 2003, 21:20

Robert,

I agree with everyone else..there are ways to get power but nothing astonishing without taking big risks.

One risk- you pay alot and it seems like your car doesnt make the power it should (but its under warranty)

Two risk-you pay more money and you get a supercharger that voids warranty but it does make more power. Problem is that its not proven on the S62

Three risk- you add some nitrous to it. Not recommended for street purposes as the S62 is pretty maxed out but BMW did their homework when dealing with the engine. Its got a knock sensor that will just retard timing all the way down to 0 if it thinks something is wrong or is going to hurt the engine. Thing is...its 1/5th the price of the other 2.

Fourth risk- you find parts that you feel and are proven to either make the car faster or make it perform better and you intermix them onto the car (sounds exactly like you my friend) and you find out what you have after you are done. Maybe it does make more power than a full dinan car and probably for less!

So...the risk 2 and 3 are possible but both are shaky ways of making power

risk 4 sounds like the best....and throw in a prayer for HP just to cover all your bases

Lupo///M5 · 23rd April 2003, 22:22

Risk 4 is the option I've chosen this time around with my new M5. I don't see sticking with one tuner as being advantages. They just take too much of my money for too little in return.

chunpng · 24th April 2003, 00:49

The fool-proof way is to lighten the car. You spend $$$ adding power, you never know for sure, but if you shed weight. It's absolute and 100% quantifiable.

I thought there was a thread on ths subject, but you can shed lbs thusly:

Light weight wheels.
Light weight flywheel,
Light weight exhaust.
Racing seats,
Carbon hood, trunk, or other body parts.

I wish I could order the car without the sunroof. I never use it.

CP

BostonRocket · 24th April 2003, 00:53

Upgrade the camshafts? Kelleners sells them.

'Rocket

Vadim-SoCal · 24th April 2003, 04:52

Lets put emotions aside and look at physics of what we need to do to S62 to make more power.

In very simple terms - more air in, more air out = more HP.

Since S62 is a 4.9L engine (4941 cc, in Germany they round up due to tax reasons), one way to look at it is in terms of HP per liter potential. S54 M3/Coupe engine puts out 333HP (US) which works out to be 104HP/L. Many new 4-valve engine have very similar HP/L ratio.

So, for the sake of argument, there is no reason why S62 can not make 500HP normally aspirated.

So lets break down the airflow in and out of the engine.

Intake:

1. Air Boxes with filters. So far we have not seen any substantial gains from replacing either filters or airboxes with different designs. It does not mean that when 500HP worth of air are flowing through they are not a restriction. But right now when 400HP worth of air are going through they are not. More testing on the way.

2. Mass Air Meters (MAF). Each one is 3.5'' (89 mm). Each one flows around 900 cubic feet per minute. We have made 420HP at the wheels with only one of them. With two........... I think the math is very simple. I would leave them alone.

3. Air Intake Trumpets (Air Horns). Someone posted a picture of the insides of the manifold awhile back. Their diameter is 2'' (50 mm) and they are 12'' (305 mm) long. The length tunes where the TQ peak occurs. We have made some shorter ones to test very shortly. But they are more of TQ tuning device to help with overall TQ curve.

4. Throttle Bodies. 2'' (50 mm). Can be opened up to 52 mm. Although 2 mms do not seem to be like a big change, they could easily improve air flow by over 10%. Is it needed? Again more testing needed.

5. Cylinder Head Intake. It has a very nice stright port that feeds two 1.38'' (35 mm) valves. If it is anything like E46M3 head, there is probably not whole of air flow improvement left from classic porting and polishing. There might be some from going to larger valves abd doing some flow bench work. Any improvement will add power.

6. Camshafts and VANOS. Stock cams are rated at 252 duration on intake and 248 on exhaust. I have not been able to confirm total lift figures. In either case those are pretty mild. There are couple of hotter profiles available from Schrick and they can also make some custom ones. Going up 30 to 35 degrees and 0.030'' (1.1 mm) can make as much as 40-60HP when combined with proper intake and exhaust flow. Again more testing is scheduled.

VANOS is variable cam timing. In itself it is repsonsible for most of TQ gains over non-VANOS engines. It can be tuned through DME software and this what Powerchips was able to do.

7. Cylinder Head Exhaust. Again a very nice smooth port with two 1.2" (30.5 mm) valves. Flow testing is on order.

8. Exhaust Manifolds. Same as 540. With a proper design
I think this where 20-25HP are locked up. possibly more with hotter cams and bigger butterflies.

9. Catalytic Converters. Have to be left alone to maintain legality in US. Possibly some gains with metal cats for non-US or off-road cars.

10. X-pipe and aftermarket rear mufflers. Typically 5-7HP from both.

11. Underdrive Pulleys. We have been making them for years for different models, on M5 - 5-7HP.

12. Now ad proper software tuning and reaching 500HP should be very possible.

13. Higher Compression Ratio (CR). Stock is 11:1. This is far as I would go on street gas. Even with 94. You can never guarantee consistency. In California, 91 is all we can get.

No doubt running 12.5:1CR with even hotter cams and steeper gears one might me able to get away with 100 octane available in some states from the pump as racing gas. 525-540HP could be achievable.

14. Supercharging. With 11:1 CR you will detonate the motor, even at 6 psi and 94 gas. Car is simply too heavy to getaway with it. Been there, done that. You need to go down at least to 9:1CR and then up to 10 psi are possible.

Anyway, we just finished bringing up our stock R&D M5 to where it is suppose to be - which a separate story in itself.

R&D starts next week.

FAST 5 · 24th April 2003, 05:39

Would be a dream car, Vadim !!!!!
If you amde such a ride and could make the same for others you'd "BURY" the other Tuning companies! Your 500 HP NA M5 kit would FLY OFF your shelves!!!!!
You make it and they will come!
Robert