mnmasotto

After reading many posts on Rennlist and Pelican I decided to invest in the MoTeC Engine Management System. The knowledgeable posts written by Geoffrey Ring and Colin Belton (9m) convinced me that these guys were the real deal!!

First, I have a 1987 Carrera with a kind of "Frankenstein" 3.6L motor. The Long block is a newly rebuilt 1995 993 3.6L Motor with all new valves, ported heads, RS cams, hard lifters, valve springs, Ti retainers, Carrillo Rods, blue printed bottom end/crank and a GT3 oil pump. The exhaust system are hand built S-Car-Go 1-3/4" primary headers with dual mufflers.

Now for the bad part.: The motor originally had a high dollar induction and electronic engine management system which was sold to a third party before I bought the motor. The only other induction system the seller had lying around was from a 1993 964. This was placed on the 1995 long block along with the stock 964 wiring harness and ECU. Obviously not the best match. High flow heads and headers with a very restrictive induction system. However, the price was too good to pass and I gave it a try.

I bought a Steve Wong Chip which certainly improved the performance but the motor only made 199 HP (rear wheel) on a local dyno. Obviously not what I was hoping for. A few people suggested I get a highly configurable engine management system to try to improve the package.

I spoke to Geoffrey Ring several times on the phone regarding my problem and discussed possible solutions. The easiest most cost effective way to work a solution seemed like a MoTeC M48 Engine Management System. Briefly, the kit included the ECU, base map, induction pipe and air filter, MoTeC to stock harness converter, new high performance fuel injectors, wide band lambda sensor, MAP sensors and all the needed hardware.

The installation could not have been easier. Total install time was about 4 hours. Everything was literally "plug-n-play". I ran into two small snags. Both involved me installing connectors incorrectly. I was able to diagnose and fix the problem with Geoffrey's help in less than a few hours. His knowledge and understanding of they MoTeC Engine Management is equivalent to a Pediatric Neurosurgeons knowledge of the pediatric posterior fossa. After the installation, the car started immediately with the baseline included map. The improvement in performance on the included base map was immediately apparent. The car ran much better on the base map than my car on the Motronic System.

The following day, I drove my car to 911 Design in Montclair, CA. 911 Design builds/maintains race cars and have lots of experience installing, trouble shooting and custom mapping MoTeC Engine Management Systems. They have a high end Dyna Pack Dyno (non-inertia type). The common inertia type dynos will not allow you to a adequately optimize the ignition maps. Loren Beggs (owner, chief designer/engineer) first developed the fuel maps followed by the ignition maps. The car eventually made 237 RWHP at 6100 rpm. Unfortunately, the motor stopped making power above 6200 rpm. Loren thinks it is related to the 964 induction system and maybe the cams. I will also, do a compression and leak down test to make sure everything in the top end is OK. The performance when driving the car is absolutely unbelievable! To fix the dead spot above 6200 rpm I am considering a Varioram induction system or ITB's. I am not sure which one. But with MoTeC Engine Management my options are limitless.

No one is more skeptical about all the stated "Internet" Hp gains than me. But I tell you these guys are the real deal. This kit was not very expensive and took less time to install than my Elephant Racing Polybronze Bushings. Now I have complete adjustability of all engine working parameters; idle speed, A/C idle speed, etc.....

Below: Out with the restrictive air flow meter! In with the new air induction pipe and air temp sensor. Note the old and new injectors.

haygeebaby

Nice - got me hungry again for more horsepower.
What type of money did you end up spending on the Motec and stuff ?
And where is your air filter ?

J richard

Uhhhh....are your numbers right? That's a hell of an effort to get LESS power than a stock 3.6 motor (250hp) I don't know what your r's cams are but all that with motec should have you well into 300hp...something is amiss...no way the factory 3.6 intake is limiting it.

joey bagadonuts

The OP is quoting rwhp, so the final mark of 237 can be estimated as 279 hp at the crank, assuming 15% transmission loss. So it's actually a 29 hp improvement over stock.

The base line number, though, seems light, 199 rwph or 234 hp. Some dyno's can be a bit optmistic and ambient temp, tire pressure, oil temp, etc. can affect outcomes. But a healthy 964 motor should produce a figure closer to 212 rwhp, so I would tend to agree with the OP's assessment that the 964 intake and ECU might not have been the best match for the modified heads, cams and exhaust.

Absolute numbers aside, I would say that the 38 rwhp improvement delivered by the MoTec system, alone, is hard to overlook.

Great write up!

PAOLOP

J Richard, attention please, mnmasotto said: 237 RWHP

Sorry, just a little to late!!!

Lorenfb

"Out with the restrictive air flow meter!"

Restrictive, really? Where are the data (single independent variable) to support this?
And how much has the timing been 'pushed' over the stock Motronic values
to achieve the so-called 'gains'?

We here in SoCal have heard that the mentioned Motec 'tuner' has problems
producing more power (and basic running) using Motec on a 993 than the
original Motronic. Maybe some data tweaking on the Motec over Motronic results?

Too bad there aren't before/after dyno data with comparative ignition maps.
But as always, one needs to justify those big bucks spent with claims of perfermance 'gains'.

mnmasotto

I have had a few experienced motor builders look at my engine with the intake off. They all felt the heads were ported a little too aggressively. They felt the port work would be a little more suited for a race motor with ITB's. I can't emphasize enough the improved throttle response and driveability with the MoTeC system. Even with the SW Chip the difference is quite substantial.

The above photos are during the installation process which took about 4 hours. It would have been about 2 hours if I had a "W" type wire crimper which I subsequently bought from MoTeC for $30. I would rate the installation process difficulty factor as a 2/10.

It finally occurred to me that the real gains from this system are the improved injector technology, ability to optimize ignition maps and improved configurability of the MoTeC engine management system.

As to the low HP numbers. I am told that the Dyno used has a very conservative correction factor. Also, I think with a better set of heads (stock ports) I would have a better matched engine configuration and more HP. I am going to have a leak down and compression test performed to make sure the cylinder are all working correctly.

J richard

Sorry joey should of been more clear, I have stock to very lightly modded (wong chip/exhaust/tune) 3.6s pulling 220-230rwhp ( 252-265hp) on a chassis dyno consistantly (and I understand the variables) with factory runners...so I still think with cams, p&p headwork, headders and motec something ain't right if that's all he's getting....should be seeing something north of 300hp (adjusted) unless the cams are ground for work above 7k and haven't come in yet...the gain is good but the baseline seems way off...

joey bagadonuts

Agreed. The numbers seem low and +300 hp would be my expectation, as well, but I think it's hard to draw conclusions when different dyno's are used. And this combination of components adds a fairly unique dimension to the baseline.

The more useful information, IMHO, are plots showing ouput before and after mods. It's not quite the same as equipping a bone stock 964 motor with a new engine management system but, for this motor, the change definitely appears worthwhile.

axl911

What's the cost of the MOTEC?

Lorenfb

"It finally occurred to me that the real gains from this system are the improved injector technology"

The ultimate in hyperbole! If one believes that, one will believe in anything.

"ability to optimize ignition maps and improved configurability of the MoTeC engine management system."

And they weren't optimized by Porsche originally? More smoke & mirrors to promote mods by 'tuners'.

"The more useful information, IMHO, are plots showing ouput before and after mods."

Right, and where are they? Without them, one can claim anything!

pcar964

Let me get this straight... A stock '95 993 makes 272bhp at the crank stock. Your newly rebuilt 993 engine with Motec and other upgrades makes... 279bhp at the crank? You should demand your money back.

J richard

Well ok, As Joey said from the beginning dyno numbers are only relatve to the same conditions on the same dyno, don't need to have that discussion, and motec is arguably the ultimate setup, but there's an issue there somewhere. If somebody did a hack job on your heads you might have a big loss there, and do you know what "RS" grind your cams are? It sounds like the motor was being built to really spin, which would really hurt you down low. If more than port matching was done on the heads, particularly the intakes, you might be better going back to a stock set. Are the valves upsized?

The other route would be the full ITB and get big cams but then you'll be dealing with a highly strung motor. Could be fun tho you're half way there....

Lorenfb

"But with MoTeC Engine Management my options are limitless."

Really? The MoTec system is essentially an early '80s fuel injection & ignition system.
Hardly what one would now days consider an engine management system.

One major deficiency of MoTec is the lack of knock sensors which ALL basic
systems now have since the early '90s including the 964. Even the mid '80s
944 had knock sensors. Without knock sensors, the engine does not reach
its maximum torque under all loads and driving conditions, i.e. and prevent
engine damage the result of detonation. Furthermore, the system lacks TRIM
capabilities to compensate for variable changes, e.g. fuel pressure. Even the
964 in '89 had a basic version of this.

Have to give credit where credit is due, though. MoTec is a good basic system
for high school auto shop to teach basic engine fuel injection & ignition.
So to say that a MoTec mod is an advancement over the Bosch/Porsche Motronic
system is a joke!

Strega(UK)

In your opinion what is the best route to go then if you were looking to top 300 bhp?