3.5L / 67 or 71 mm turbo project

We have been working on All Wheel Drive M3 for the last 2 months and road tests will start on may 2013.

AWD M3 will take a lot of my time.

Meanwhile I decided to build my other E46 M3 as a Daily M3. No need to have two E46 M3s to chase times. One is enough.

3500 cc stroker
very silent ehaust system
pump gas only
67 or 71 mm turbo to be able to have the maximum low end torque
(could not decide what to choose 67 or 71 mm)

custom automatic transmission, 8 speed, this is very exciting.
OS Giken LSD
Full interior, no weight reduction
380 mm new Brembos are waiting to go into this E46 M3
two colored leather DASH, this will be exciting

all and all I want to build a lovely Daily E46 M3. Will use one of my E46 M3s to chase for fast times. At the same time will work on one of my E36 M3 Euros to chase fast times.

In order to build a single turbo manifold, I needed to wait till the AWD M3's work decreases. We work on AWD m3 all the time.

Called Maximumpsi and talked to Luke and asked him for a turbo manifold. He replied that they dont sell manifolds only, just within their kits.

Explained Luke about my Project, I wanted a Daily full interior 700 whp M3. He understood what I wanted exactly.

Luke decided to sell me Maximumpsi's beautiful tubular manifold. It has nice curves and excellent welds. It is non-divided. Does not require a scavenge pump.



Thank you Luke & Maximumpsi. Without your tubular manifold I would have to wait for at least 6 more months.

pump gas only? I'd go with a 6766..

Originally Posted by MarcusLSB

pump gas only? I'd go with a 6766..

Marcus,

I plan on sticking to pump gas and avoid filling methanol tanks etc. Want to haul my son and want to drive as if it is a factory m3.

Why do you recommend 6766?

Originally Posted by Twin_Turbo_S54

Marcus,

I plan on sticking to pump gas and avoid filling methanol tanks etc. Want to haul my son and want to drive as if it is a factory m3.

Why do you recommend 6766?

On pump gas and 11.5:1 the 6766 just seems like a better pairing, quicker spool, sure less top end but i'm not sure how much of that topend you're really going to be able to take advantage of.. I think the 6766 wouldn't even be all in on pump. While I've never seen anyone do 700rwhp on a 11.5:1 on pump gas i have seen plenty make 700rwhp+ on 6766's with low comp. HPF's track car broke 700rwhp easily on the 6766 with a built 11.5:1 motor on c16.

Also when you say 71mm are you looking at the newer 7175 or the older 7168 CEA?

Also when you say 'pump gas' are you building the car around that requirement, or is that just what it PRIMARILY will be driving on.

On my 11.5:1 build I'm running the 7168. I might try my 7275 but Jason at ProEFI wasn't impressed with it.. however i never saw a dyno graph. I was actually going to go 6766 but i figured I have the 7168 laying around, might as well try with it first. The car will be on flex fuel though and I'll likely keep the pump numbers very conservative.

Originally Posted by MarcusLSB

On pump gas and 11.5:1 the 6766 just seems like a better pairing, quicker spool, sure less top end but i'm not sure how much of that topend you're really going to be able to take advantage of.. I think the 6766 wouldn't even be all in on pump. While I've never seen anyone do 700rwhp on a 11.5:1 on pump gas i have seen plenty make 700rwhp+ on 6766's with low comp. HPF's track car broke 700rwhp easily on the 6766 with a built 11.5:1 motor on c16.

Also when you say 71mm are you looking at the newer 7175 or the older 7168 CEA?

Also when you say 'pump gas' are you building the car around that requirement, or is that just what it PRIMARILY will be driving on.

On my 11.5:1 build I'm running the 7168. I might try my 7275 but Jason at ProEFI wasn't impressed with it.. however i never saw a dyno graph. I was actually going to go 6766 but i figured I have the 7168 laying around, might as well try with it first. The car will be on flex fuel though and I'll likely keep the pump numbers very conservative.

Compression will be 9:1 in order to be able to use pump gas only. There are no rules but just to be able to buy pump gas easily.

I am in between a 6768 and 7175.

Have you been happy with the way 7168 spooled on the Street?

Thanks for the kind words Mert! I think that this will suite your needs perfectly!

Originally Posted by Twin_Turbo_S54

Compression will be 9:1 in order to be able to use pump gas only. There are no rules but just to be able to buy pump gas easily.

I am in between a 6768 and 7175.

Have you been happy with the way 7168 spooled on the Street?

Ahh, sorry.. thought you were going 11.5:1. Still would do a 6766. Why the 6768? I know the bigger exducer means more topend but even on the 6766 both HPF and ProEFI/Saad were carrying power to redline.

This graph is the 6766 on a built 9:1 motor on pump gas. I know its not your 700rwhp target.. but its also on a 3.2, not a 3.5l

The 6768 has a shitty top end in comparison to the 6766. The 6766 is a new redesign; 6768 no longer being made iirc.

Originally Posted by MarcusLSB

Ahh, sorry.. thought you were going 11.5:1. Still would do a 6766. Why the 6768? I know the bigger exducer means more topend but even on the 6766 both HPF and ProEFI/Saad were carrying power to redline.

This graph is the 6766 on a built 9:1 motor on pump gas. I know its not your 700rwhp target.. but its also on a 3.2, not a 3.5l

Marcus, thank you very much for the details.

3,500 cc / bigger cams / aggressively ported head/ + 1 mm oversize valves/ 9000 rpm "might" give more power.

In fact my goal is not to make this or that whp. I do not have an exact goal.

I would like to taste E46 M3 and drive for at least 200.000 miles and wear my M3. Want to change brake pads, A/C filter, so basically want to use my M3.
I can live with 600 whp happily. This M3 will be a Daily commuter and 600 whp for a Daily car is enough. I drive 997 Turbo Daily, 550 flywheel hp is more than enough for a Daily car

Originally Posted by Commanderwiggin

The 6768 has a shitty top end in comparison to the 6766. The 6766 is a new redesign; 6768 no longer being made iirc.

I ve asked Precision and they quoted for 6768, they did not mention about production. Why do think top end of 6768 is shitty?

Originally Posted by luke@maximumpsi

Thanks for the kind words Mert! I think that this will suite your needs perfectly!

Luke, I thank you for accepting to sell this lovely manifold. There is a lot of effort and sweat in this manifold.

Wish you sell as many kits as possible

You must detail this: "custom automatic transmission, 8 speed, this is very exciting. "

Good luck with the build!

The 6768 vs 6766 is no comparison...6766 is better in all ways. 6768 runs out of steam in the top end vs the 6766 as well.

Originally Posted by Commanderwiggin

The 6768 vs 6766 is no comparison...6766 is better in all ways. 6768 runs out of steam in the top end vs the 6766 as well.

do they have different shape compressor wheels?

***305;f the comp wheels are the same the air flow has to be identical and hence 6768 should not run out of steam.

Originally Posted by Twin_Turbo_S54

do they have different shape compressor wheels?

***305;f the comp wheels are the same the air flow has to be identical and hence 6768 should not run out of steam.

It's possible they came out with a redesign on the 6768 I suppose...dunno give them a call. Larry@SoundPerformance would be the guy to ask.

Originally Posted by Commanderwiggin

It's possible they came out with a redesign on the 6768 I suppose...dunno give them a call. Larry@SoundPerformance would be the guy to ask.

They did, they replaced the old 6768 with the 6768 CEA, same goes for the 6766 (which is a CEA). The 6768 that HPF used to use was not CEA (iirc).

...

Mert, sometimes its just not worth reinventing the wheel. The 6766 has been proven to make some great numbers and is matched very well with the 3.2L S54. I don't think some additional porting, valve work and a .3L difference is enough to justify the 6768 or 71xx. That's just me though.

Call me silly, but I would go with something even smaller...like a 6262 on the street. Everyone has their preferences...

Originally Posted by PEI330Ci

Call me silly, but I would go with something even smaller...like a 6262 on the street. Everyone has their preferences...

I didn't think Ben's HPF Stage 2.5 spooled much quicker on the 6466, not enough to justify the drop off on the top end. Maybe a 6466 on a 11.5:1 would be different.

Originally Posted by PEI330Ci

Call me silly, but I would go with something even smaller...like a 6262 on the street. Everyone has their preferences...

Adam, this means you prefer more torque, better low end power.

Originally Posted by MarcusLSB

I didn't think Ben's HPF Stage 2.5 spooled much quicker on the 6466, not enough to justify the drop off on the top end. Maybe a 6466 on a 11.5:1 would be different.

67 vs 64 mm = 3 mm difference should affect spool a lot.