1997 M3 4 Door with LS/T56

**Tim Mc** · 11-24-2018, 07:52 PM

Thanks!

Put a bit of time on the car - I hate wiring. Finally decided to connect the factory tachometer - assistant volunteered to play with fire (melt shrink wrap) and weld (solder). So took couple of days to connect 4 wires (ground, switched 12V, tach signal in, and tach signal output).

But it works! We employed the Dakota Digital converter box to go from the Holley HP tach output to the OEM tach. Signal in - 8 cylinder. Signal out - 6.

We pulled the cluster to connect the tach signal to the harness. Then ran the wire across/beneath the dash to the large grommet in the passenger footwell (along with all the other extra wires) into the engine compartment.

At the same time, we took liberty in pulling a few annoying cluster bulbs (MX light, ASR light) and install full hardware on the passenger footwell. Amazing what a few screws will do to dampen rattles!

Works as expected with some inaccuracies.

The tach reads 500 rpm when the engine is at 675 idle. If we plus the Dakota Digital up (ability to fine tune the needle), it reads high at higher RPM. We will play with it a bit, but surprised things aren't more linear between the two. Only a short drive so...might be different in the daytime.

Quite fun to watch the needle hit 6500 rpm with the soundtrack.

Not many images...original backside bulb layout of the cluster:

Close up:

Nice touch, BMW ID's each bulb.

Separately, we are experiencing a bit of a change to the LS7 clutch actuation. It has gotten very light and a bit of noise is present that wasn't previously (can only hear when the engine is off). The difference occurred during the dyno runs.

We bled the system twice with no bubbles and full clear fluid. Chris M had issues with his LS7 setup - no shifting above 4000 rpm (locks out). We can shift at all RPM, but something did change. Apparently LS7 setup might not be the ticket for these swaps (or other?) possibly due to a self adjusting feature. We aren't sure.

Unfortunately, time is nearing the end for this project for the near term - assistant and I will be heading overseas while the M3 will go into long-term storage. The car has a 1500 mile journey ahead of it in the next couple of weeks. Hope nothing falls!

**Laminar** · 11-26-2018, 01:47 PM

Originally Posted by Tim Mc

Great results! That's a beautiful power curve.

**RulyLSX** · 11-26-2018, 11:31 PM

Very good news on the HP numbers, great build and it sounds damn sexy!

**Tim Mc** · 11-28-2018, 08:53 PM

Thanks! And agreed. Believe we were conservative at the lower end timing...not adjusting it from Holley's already conservative timing curve of the off the shelf ignition map. Only focused above torque peak to see the big numbers...

Maybe we will get to hooking up the heater...

**Tim Mc** · 12-01-2018, 10:22 PM

Today was heater day. Few trips to Autozone for various preformed hoses, 5/8 and 3/4 hose supplies.

We skipped the heater control valve and tied the engine's heater barbs directly to the heater core barbs.

The supply off the engine was split to the two supply barbs on the firewall and the return was direct.

Noting we have never had heat as the heater control valve was completely plugged...unsure of the integrity of the heater core!

We are crossing our fingers at leakage...couple of hours with nothing obvious, but could be going direct under the carpet, etc. First drive is tomorrow with the subarctic departure on Thursday...

No pic as we are not exactly proud of a poorly planned hosing - half because of the space allowed and half because I expect it to leak and we pull the crap back off!

Will note it starts right up on the 40 degree mornings (that is cold in FL!).

Appreciate the links/info on equipping the car with a creature comfort!

**Tim Mc** · 12-02-2018, 05:50 PM

100 miles on the add on comfort. Of course FL is 70-80 degrees right now and do understand the reason for the heater control valve. Even when the dash controls are not set to heater, air still flows thru the warm heater core...heat is on all the time although at a lower intensity.

Does appear folks can tie the two feeds on the firewall into a single hose - likely even with the heater control valve. Surely there is a clean compact way of doing so vice the large brass 't' we have used. We could have had more forethought when the engine was out to lay out the routing. Always next time when the engine comes out (when we add ported heads and a larger camshaft!).

BL: Great news for us - it works!

**Sacrificed** · 12-03-2018, 09:05 AM

Originally Posted by Tim Mc

100 miles on the add on comfort. Of course FL is 70-80 degrees right now and do understand the reason for the heater control valve. Even when the dash controls are not set to heater, air still flows thru the warm heater core...heat is on all the time although at a lower intensity.

Does appear folks can tie the two feeds on the firewall into a single hose - likely even with the heater control valve. Surely there is a clean compact way of doing so vice the large brass 't' we have used. We could have had more forethought when the engine was out to lay out the routing. Always next time when the engine comes out (when we add ported heads and a larger camshaft!).

BL: Great news for us - it works!

Glad that worked out for you. Great build so far and definitely makes me look forward to swapping mine one of these days.

**Tim Mc** · 12-04-2018, 09:28 PM

Worked with a paintless dent repair expert that I've used for nearly a decade...Magic Mike. He did his sorcery on over a dozen body impacts. ~90 minutes and $250 left us with a nearly unmarred car! Even the healthy dent in the rear quarter panel was massaged full! I was convinced bondo was in our future if we decided to clean up the car to the next level. Well worth the investment. Only one that was not addressed is in the C pillar as it is double walled for roof strength - so no backside access. It is very minor though.

Sacrificed: We highly recommend the mod! Tonight we executed a nice second gear sprint following a tight 90 degree right-hander with a line of awaiting opposite traffic. The 'little' 5.3 tagged the rev-limiter getting up to speed with 4 heads bobbing in the leather seats. Surely any car guy in that line of cars was smiling hearing that V8 soundtrack. It is a very enjoyable package - as the E36 is known for.

Just passed 3100 miles on the combination - 19.6 mpg average. I tend to exercise the power so lowers the fuel economy a good amount. I'd like to see 25 mpg on the 1400 mile road trip this weekend. Any bets?

Will be very tough parking it for a few years - we were just getting started!

**Tim Mc** · 12-05-2018, 08:02 PM

Changed the engine and trans oil and cleaned up the interior with a new center console as the original had all broken screw tabs which allowed it to float/dance. Bought a used one for 36 bucks...works like a champ. Even came with another delete panel for the no longer ASR button.

Additionally, the clutch is so light that the pedal nearly won't return from the floor! The OEM BMW spring assist creates a challenge as the pedal assist is goes from nil to alot. As others have done, we pulled the spring off the pedal assembly tonight.

After 5 miles, the clutch feel is like one expects...although we so believe there is a discrepancy within the LS7 clutch assembly. It still holds full torque, but appears the return spring has gone limp or a portion has failed. It has been consistent for last 400 miles so pending the cold weather up north...should be ok.

**RulyLSX** · 12-06-2018, 04:32 PM

woohoo no assist spring team! haha

**Tim Mc** · 12-11-2018, 05:57 PM

:-)

Unfortunately, the clutch has more issues than pulling the spring will fix.

Success!

Completed the two day journey from FL to Iowa for long term storage. 1478 miles covered...24.3 mpg at 2200 RPM/79 MPH. If it weren't for some stiff winter head winds and a bit of idling in the middle of I-57 for a roll over (50 minutes!), we would have hit our target of 25.

Upon arrival:

Thanks for some family pulling some strings to gain access to a warm wash bay at a local dealer (it was 10 degrees outside):

Tweaked the Holley HP on the fly...leaning and adding spark advance - gave a solid 1.5 mpg at cruise (which I didn't have).

Things to fix:

- LS7 clutch assembly has failed in some fashion (very stiff pedal and little throw). It never slipped or failed to shift, but certainly not good on the synchros...
- Heater core leaks...fogged the windshield. But I was toasty warm even in 40 degree temps without even turning it on! Hence the requirement for a heater control valve to keep the hot coolant out of the interior.
Additionally, the two feeds to the core are likely sequentially timed...ie both open is very hot inside...likely only one is used for most applications. In other words, tying them together may create an all on or all off situation.
- Highspeed rhythmic vibration...likely the driveshaft at 80 and above. I will chalk it up to worn rear subframe bushings that are causing issues...or a diff that has issues. We didn't experience that when first installed.
- One window rubber needs replaced...amazing how one small missing rubber piece adds to interior noise volume due to wind...noisy!
- -3 degrees of camber - possibly we should have had more toe in, but at high speeds this car wanders something fierce. We also weighed it down with 200+ pounds in the trunk - so added to the fun. We will switch the front strut mounts correctly and be happy with the -1 or so it gives.

Overall, extremely fun project that with essentially a stock 5.3 which has loads of potential...disappointing to put it away for a few years...thanks for all the assistance and posting/threads!

**Laminar** · 12-11-2018, 07:57 PM

Where in Iowa??

**BigL350** · 12-11-2018, 10:39 PM

Good luck on your new endeavor. It’s been a pleasure watching your project come together. Sorry you have to put it down for a while.

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**wbrentr** · 12-13-2018, 09:23 AM

Originally Posted by Tim Mc

:-)

-Additionally, the two feeds to the core are likely sequentially timed...ie both open is very hot inside...likely only one is used for most applications. In other words, tying them together may create an all on or all off situation.

I wonder if it is a volume thing. May still be able to tie them together and have a reduced flow through the heater core.

**RulyLSX** · 12-13-2018, 12:01 PM

Thank you for sharing your build with us Tim, great read and enjoyed the ride

**Tim Mc** · 12-13-2018, 07:08 PM

Iowa: between nowhere and desolate...actually between Des Moines and Council Bluffs. 10 degrees is no joke...been in FL too long.

We will be back...my assistant isn't quite driving age so...hopefully that will sync up upon our return.

Heater: it is possible that tying them together with a heater control valve will be different. The heater coolant lines certainly are bulky, especially the Autozone quality hose which is essentially slight flexible tubes...

That ~15 degree intake air really added some HP! Gave emphasized meaning to cold air intake...

**Tim Mc** · 05-12-2019, 06:49 AM

Made a quick trip back to the states for business and a quick look/see of the sleeping M3. Unfortunately, it was too short to pull it out for a spin. An image:

To keep the M3/LS withdrawal symptoms away - I've been undertaking the German experience:

I think the M3 would be more enjoyable...

**BigL350** · 05-12-2019, 11:28 AM

Bad ass!

Next you’re going to post some schweinshaxe and hefeweizen to make us really jealous.

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**BillyDee36** · 06-24-2019, 12:32 AM

Originally Posted by Tim Mc

Did your trans come with this pigtail reverse light switch? Or did you buy it? That’s a way better option than hammering my tunnel.

**TipsyMcStagger** · 06-24-2019, 07:49 AM

Originally Posted by BillyDee36

Did your trans come with this pigtail reverse light switch? Or did you buy it? That’s a way better option than hammering my tunnel.

Motorcraft Part # SW-5857
Ford Part # 1R3Z-15520-AA

**BillyDee36** · 06-24-2019, 11:19 AM

Originally Posted by TipsyMcStagger

Motorcraft Part # SW-5857
Ford Part # 1R3Z-15520-AA

Thanks Tipsy!

**Tim Mc** · 06-27-2019, 03:34 PM

BillyDee36: Our trans actually came with that switch (T56 Magnum). We never hooked it up though...something for the future.

Thanks Tipsy!

**Laminar** · 09-24-2019, 10:26 AM

Has someone been sneaking your car out of storage? I saw a pretty blue M3 sedan cruising a week or two ago and thought of you.

**Tim Mc** · 09-24-2019, 08:15 PM

Laminar, not to my knowledge! Although, timely, as I'm back in the states for a short spell and taking a bit of leave in Iowa later this week...hope to pull it out for a bit of annual maintenance. Hope the weather holds...

**Tim Mc** · 09-28-2019, 09:30 PM

Made it back to Iowa with some nice weather...time to pull it out for some exercise and annual maintenance - the Holley EFI'd L33 fired right up after 10 months of stagnation:

Oil change, heater core bypass...and blow the cob webs out a bit. Told the assistant that I would do a burnout for him...I did two! Tires slip in 2nd as well...old Firestones.

All clean for another year of storage...bummer.