Monday, May 26, 2008

DMC's (new) Stage 1 Upgrade: A review

(Updated 07/10/12, added some notes and a video at end of this blog)
(Updated 06/06/08, added video at end of this blog)


DMC has been selling and installing engine upgrades for our DeLoreans for a while now. They currently offer two options, a "Stage 1 Exhaust/Ignition Upgrade" and a "Stage 2 Performance Upgrade".

The Stage 2 option is an engine, ignition, and exhaust system revamp that roughly adds an extra 70Hp to a your stock PRV engine. DMCH has previously stated that only engines with 50,000 miles or less, qualify for the upgrade; however, there is a Stage 2 parts only option that is built and delivered on a zero mile crate engine, as a $7125 option.

Parts Kit: "Stage 2 Perfomance Upgrade"

DMC has very recently re-introduced the "Stage 1 Exhaust/Ignition Upgrade" option, which is similar to the Stage 2, but without any engine modifications nor engine mileage restrictions. The Stage 1 upgrade is available as a parts kit, for $2195, or installed at your local DMC affiliate for $2995.
Parts Kit: "Stage 1 Exhaust/Ignition Upgrade"

The original Stage 1's headers and pipes were Jet Hot coated, and while they looked good upon installation, the upgrade got put in hiatus after they were showing premature surface rusting, as the coating was being abrasively rubbed off vehicle use. In order to address this, this second release is an all-stainless solution (headers, with two catalytic converters, a custom muffler, and brackets). Something else addressed was that the previous Stage 1 & 2's upgrades were sounding too "muscle-car" like, which while some liked that, to me (and apparently others as well) this did not sound appropriate for this car, to its European roots (and parts). To address this, DMCH selected a different muffler solution on this version, to get that "European exhaust sound".

I've seen and heard the previous Stage 2 installs (never saw a Stage 1), and it was enough to get me curious on the halted Stage 1 option. Since I have had my car, I felt that our stock exhaust just didn't have the right sound either, especially as you up/down shifted, and the tiny exhaust tips just looked plain silly (I had even added some Pepboy chrome tips to attempt to address that). I couldn't personally justify, or had the pressing performance need to have a full Stage 2 upgrade; however, with this new re-engineered exhaust solution being available again, and a personal financial alignment of the planets, I decided to go for a Stage 1 upgrade.

Here is a "before" picture, taken in the early morning of day of the the trip to DMCFL:

Part of the joy of ownership for me is that I like to work on my car, and have been doing so for the last few months. However, with our hot muggy Florida days which have prematurely started, a 90 minute A/C drive to Bonita Springs (DMCFL location) for a one day installation, didn't sound like too bad an option for me to justify.

As usual DMCF's staff there is very knowledgeable and professional, in their impressively clean and organized facility (lobby and garage bays). They began as soon as the car cooled off, and in the late afternoon, the car rumbled up as soon as it was all put together. The new exhaust sound was impressive, it just did not sound like the same engine - but the true test would be on the road. If you are wondering about doing this upgrade yourself, it looks like a pretty straightforward bolt-off, bolt-on job, if you are fortunate enough to not have any of the original manifold mounting bolts snap.

This is what the complete part kit looks like...

Stainless Headers
Stainless Catalytic Converter (2)
Stainless Custom muffler
Stainless Associated pre-bent tubes, 2.5"
Stainless Clamps (2)
Stainless Mounting brackets, w/rubber isolation mounts (2)
Stainless, Polished, Exhaust Tips
Muffler heat shield
Cold Air Intake kit
K&N Air Filter
Nology Corepack
Nology Wires
Spark Plugs, Silverstones
...and, a Cold Air Intake Kit

So after it's all done and paid for, what does it look like? What does it sound like? What does it feel like? What does it contribute? What can it do? ...let me attempt to answer those questions, with specific observation right out of the shop, and with now with several weeks of driving it.

Evaluation 1: Highway Driving
Driving for a very, very short distance in street traffic, basically from DMCFL to the highway, was fun. The car had a very different sound, not tuner, not muscle, definitely a European car sound – more on that later. On the trip home at highway speeds, I was reminded of my last vehicle's exhaust upgrade to our family hauler: a 2000 Expedition, 5.4 liter, to which I converted it to true dual exhaust with Magnaflows – now that, was a muscle car sound (and appropriate for that V8). And I was reminded of it because similarly, there was an approximately 2100 rpm harmonic resonance that reverberated into the cabin. Again, this highway ride was not really the showcase of this exhaust system, as it hummed (sometimes droned) for over an hour around the same revs (low 2000's in 5th gear). At that range, the sound is slightly elevated over stock, and at some points as you press on the accelerator, it is a sound that you can feel all around you.

Evaluation 2: MPG difference
As stated above, the trip to DMCFL for me is about a 90 minute, point to point trip; and it consists mostly of 90% highway (70 mph speed limit) driving. I filled up the tank and cleared the trip odometer just before the inbound trip, and then re-filled up again before leaving DMCFL to a) check my pre-Stage 1 install inbound mpgs, and b) reset to for outbound mpg calculations, with the Stage 1 installed. A few blocks before arriving home, I filled up the tank again, and noted the miles for the return trip calculation.

Pre-Stage 1: 26.0 mpg
With Stage 1: 27.5 mpg
Interesting. I suppose the more efficient exhaust system, in addition to the hotter spark burn, new sparks, contribute to the slightly added efficiency of the engine. I believe I've captured a good comparison here, as in both cases the conditions were very similar: Full tank fill up (O89), 90% highway miles (same roads, miles), no passenger, A/C air on, no significant winds, and cruising at a more or less a steady 70mph. Still, taking way any unaccounted for, or difference variables, it probably safe to say that Stage 1 is a 5% mpg increase, over the stock exhaust.

Evaluation 3: The look.

The Stage 1 exhaust system looks very professionally done, and in fact is very well integrated to the block, frame, and rear fascia. The O2 sensor is now very easy to access, and the oil filter is still easy to get to.

And even though I haven't checked it yet, eliminating the old system's crossover pipe (behind engine, above transmission), now provides interesting access opportunities from underneath the car, to the back of the engine, by the clutch fork lever mechanism.

Standing, and even crouching, from a few feet away you can barely see the catalytic converters; most of what you can see underneath is the union of the headers to the single pipe that goes to the catalytic converter. BTW: That union/bend is still within the lower limit of the frame. Every time I see them as I walk up to the car from behind, the plumbing reminds me of two snakes with their heads elevated in a rising coiled strike position. The new muffler sits a little lower than the stock setup, and is partially visible from the bottom center lip of the bumper.

Here is a squirrel's eye view of the left hand side plumbing.

The final touch is classy, the polished stainless tips have a "DMC" logo laser etched on the top, and look significantly more impressive than the smaller stock exhaust tips.

There are two things to note that I am iffy about, but these both come down to nitpicking. First is for some reason, the right tip extends out just a little bit further than the left. It doesn’t seem to be in the installation, I’ll have to check that further. The other is that I do not care for the exhaust clamps used to join the muffler to the 2.5 inch exhaust bends. I can try to move them so they expose the bolts less, but instead I will replace that nuts and bolt look altogether, with some stainless band clamps.

The engine bay also benefits from this upgrade. First, both the warm air hose, that rises from the manifold’s stove bracket, and joins up with the stock cold air hose, are removed. This is good because that is a typical eyesore as on older cars as it tends show surface rust. Mine had been long gone, and had been replaced with a similar bypass hose. You have the option of replacing the stock configuration today, with DMC's "Performance Air Intake", or Hervey's "Cold Air Input Tube", or if you search around there are tips on do-it-yourself versions. The Stage 1 kit now includes this, and the look in this area if you had not previously done it, is now much cleaner. Eliminating the old system is not an issue for Southern climate cars, but it may be a bit of (probably minor) an issue for the few cars that are run in colder weather.

Eliminating the old system is not an issue for Southern climate cars, but it may be a bit of (probably minor) an issue for the few cars that are run in colder weather.

There there is the Nology upgrade's contribution to the engine bay, it now adds thick blue Nology wires running to your plugs, along with an associated braided ground cable (one per plug).
..of course the Nology powercore is also installed on the vertical wall, and it visually states that this is not a stock setup.

Hmm, as I write this it occurs to me that as far as appearances, you really can't differentiate if this if is a Stage 1 or a Stage 2 upgrade.

Evaluation 4a: Horsepower/Torque
I have no real data, but theoretically there is supposed to be a 8-15 Hp gain by going to this less restrictive exhaust system. I have no real data to track pre and post Stage 1 results, so all I have is a subjective evaluation as follows.
Not often, but I have pushed my car to redline on 1st , quickly then to 2nd to see what she could do (stock). So as a baseline, I kind of know how she responds in a 0-60mph run. Curious as to what this new exhaust system would contribute, I did the same on the same roads I've previously pushed her.
There is definitely an added kick in 1st gear, not a monstrous boost, but definitely noticeable. A quick 1st gear redline, to 2nd gear to 60mph "seemed" and "felt" faster – but again I have no real data, dyno readings, to back that up. Stage 1 definitely contributes a few more ponies of Hp into increased torque…and I suppose if you took the cats out… Disclaimer: not advocating to do this, nor to pull your mattress tags either. : )

Evaluation 4b: Street Traffic Driving
If what you've read so far leads you to believe that this upgrade is just "not all that", well, I have saved the best for last. I drove it for several hours for the next two days after the upgrade, to continue the evaluation. The driving was all local street traffic driving, and this, is where you drive with a smile on your face with this upgrade. First, firing it up in the garage is just so cool, it just goes "baRRRooom" and at first you can't really believe this is your same car, with that sound. Once on the street, the sound of revving up 1st is just plain fun – it's like all of a sudden your car sounds similar to the cars that you admire for their engine sounds. Then, in between passing it on from 1st to 2nd, you are rewarded with another new "foreign" sound, a momentary deep exhaust burble, just before 2nd gear kicks back up the Euro-sonic track. The more revs you pull the cooler the sound effect…there goes that gas mileage improvement! And my favorite effect so far, by far, has to be a slight tap of the accelerator as you coast slowly in neutral, "VRrooommm": totally pointless, but totally cool, and totally previously unachievable. In fact as I pulled into a gas station I did just that, and as I came out of the car some young kid in a spruced up Acura stopped to say my car was "Gangstah!" …yeah, I'm going with that was a compliment.

This upgrade is most definitely best appreciated, tuned for, street driving.

So there it is. Was it worth it? You will have to make that decision for yourself, for your own reasons, for your car; however, for me it is a resounding: "Yes." Not only am I (still) driving a DeLorean, but now a DeLorean with a really great sounding exhaust. To me the Stage 1 upgrade adds significantly to the overall driving pleasure, and ownership experience.

...and PS:
I hope everyone enjoyed a great Memorial Day today.


Update (06/08/08)
I tried taking videos of the exhaust system from the outside, at idle, etc., but they were all pretty boring. Although this video is in "shaky cam", I believe that this one best conveys how the new exhaust system sounds to the most important critic - you the driver.

In the video the D starts from a near dead stop, is shifted up to redline on 1st gear, then quickly shifted to 2nd up to 60mph, and then drops to Neutral (listen for cool "burble" sound) to a coast.

Here is the video:

...ok, ok, here is the standard driveway idle and rev shot:


Update (07/10/12)

So it's been over 4 years I've had this Stage 1 system installed in the car.  Since then, there are other options out there ( , , ) for similar systems.  In addtion DMCH has modified their Stage 1 from as described here: Nology system no longer included, and the muffler is slightly smaller.

Still I have enjoyed this modification/upgrade to 2109 very much.  Four years later I still smile listening to the exhaust sounds as I row the gears, and I can actually chirp the rear wheels on a turn - both very non-stock attributes for a DeLorean.  I recently made an in car video compilation of three different type of throttle performance sounds.  Here it is, hope you enjoy it.

If you have a few minutes, be sure to check out the "Best of" postings. Thanks.

Sunday, May 18, 2008

The RPM Relay – A modern update

(Edit 02/21/16:  Updated links for Dave's website of related products.)

RPM Relay, a synopsis
The RPM relay, resides in your fuse/relay area. Physically it is a small boxy plastic case made either by Bosch (black), or Volvo (green). In our cars a thick wiring harness plugs into to it, just above the fuse box, under the door lock module. The RPM Relay’s function is essentially simple, as long as it senses a tachometer signal (engine use), it supplies power to the fuel pump. Additionally it also provides power to the warm up regulator heater, and it turns on the main fuel relay (Lambda relay). When the RPM Relay goes (or starts to go) bad, your cars stops dead due to no lack of fuel being pressurized into the system. Now, guess what part on a DeLorean is (still) a notoriously high failure part? Answer see 1st and 2nd words in sub-title above.

If your RPM Relay fails on the road, there are some options to get get you home.
One thing you can do, is to remove the RPM Relay and jumper (a thick paper clip will do in a pinch) terminals #30 and #87; this will supply constant power to the pump. This is only temporary as it will affect ECU/Lambda controlled fuel mixture, and overall is probably not safe to run for an extended period. John Hervey's SpecialTAuto site has an excellent reference of this emergency jumper solution here.

The other option up to now has been, to carry a spare RPM relay. Just in case.
Available at:
SpecialTAuto: here
Your local DMC affiliate: here
Remember though, these have the original late 1970's/early 1980's design.

Well, now that we are in the new millennium, we have a new option thanks to Dave M. (an electrical engineer and an active DeLorean community participant), aka “Bitsyncmaster” on DMCTalk and the DML. Read on...

Dave’s re-engineered RPM relay
In February of 2007, Dave sketched up plans for a modern update to the notorious RPM relay. His schematic replaced commonly used 1980’s discrete components with a modern solid state components and a micro-controller/processor. To really appreciate the difference between the original design, and Dave’s, look at the picture below (my old OEM relay on left, and Dave’s version - click picture for larger view).

The old relay reminds me of the results of an old Radio Shack electronic kit, and the new one just looks so modern with its really tiny surface mount components. Beyond duplicating the basic function, he also added an optionally active “Hot Start” feature. This will actually prime the fuel system, for 1 second at 1 hour intervals when the car is parked. Some consider this a controversial feature because it is workaround, to a different problem that needs to be fixed. Again, it’s optionally enabled by the user, and this could mean the difference between a drive-able car or not, at least until the complete fix to the problem is addressed.

Features of the Re-Engineered RPM Relay
Back to the main feature of the this new RPM Relay design. There are some very big difference in this new and modern relay:
a) Less current draw: This new design draws 16ma on ignition, and 20 ma in operation. The original relay draws 260ma. That’s a 92% reduction of current on the new design!
b) Eliminates a constantly energized coil: In the original design this relay maintains a constantly energized coil when it is on, this function is now replaced with solid state components (the differences are visible in the picture).
c) Less heat: Since the original relay sucks up more current through the discrete parts (see coil above as an example), they generate more heat. So much so, that you cannot touch the internal components on the original relays after a long drive. The new design, on a similar drive, runs barely warm. I know because I performed that test with the two designs.

To anyone who has dealt with electronics and reliability knows, the three benefits above, translates directly into a now significantly more reliable part. Cool.

As of this writing Dave is currently asking $75 to upgrade your old relay, along with a refundable $50 "core" charge. The upgrade consists of a completely new and professionally made circuit board, with modern components soldered in, and using your existing case and connector.

RPM Relay in use
I have been running this relay as a beta tester for Dave, since January 2008 (5 months as of this writing). In that time, I have driven my car every weekend on either 10-30 mile cruises, or often to longer distances to local car shows (including during high 90+ degree Florida days). In that time we also took the car on a 600 mile round trip that included 3 hours of continuous driving. The relay sits quietly in its place, performing its function, and frankly I have forgotten that it is there - which is exactly what this part should contribute to our cars.

Hat’s off to Dave and his improved design of the RPM relay, this is an excellent one person contribution to the maintenance and continued longevity of our cars.

These kind of upgrades are typically not as “fun” as other things that you could add to your car: You plug it in, and apparently you don’t really “get”, or see, any noticeable improvements. While that is true, you should consider this a preventive maintenance, a reliability improvement, an upgrade. And while those are often not “sexy” upgrades, in the end, it is money well spent on your hobby/passion/baby (as it were).

If you’d like to consider or purchase one of the new solid state relays from Dave, you can contact him at: or PM “Bitsyncmaster” on

Edit 01/03/09:
One Year Update
My solid state RPM relay is the oldest production unit in operation. It has been running without incident now throughout an entire year, including some near 100 degree ambient Florida temperatures, and several 3+ continuous hour trips. Many other owners have now been running Dave's relay with similar excellent performance.

Edit 02/21/16:
Eight (!) Year Update
Yup. Still all good. Great product, a must have if you own a DeLorean.

>>> If you have a few minutes, be sure to check out the "Best of" postings. Thanks.<<<

Sunday, May 4, 2008

DeLorean Clock : Gallery of owners' updates

It has been almost a couple of months that I published the "The DeLorean clock, a modern update" blog post.

In that time I have been enjoying my clock on every ride that I take, as well as have corresponded with a few other owners in their upgrades as well.  As they've installed their now functioning clocks, the feedback from them has been very complimentary as to the work that was done by Dakota Digital, and the overal look after installed.  Here are a few pictures and feedback that I have received:

Bill S.
"I am a very happy camper to have such a nice looking clock that really works.  I was able to get the clock back into the "D" today and it looks fantastic. WOW. It was worth every penny they charged and more. The look is great and your instructions made the hook up childs play. I am delighted to have a working clock.  I actually like the no holes in the clock face look better than the original set up."

Jon in Spain.
"Installation was very easy."

Bruce in California
"It looks great. We did a car show this past weekend with our club and all were impressed with my new clock! Some thought it could never be done."

If you would like to replace your current non-working DeLorean clock, this seems to be a very good alternative. 
Check the link above for more details.
And if you do make the upgrade, zap me over a quick picture for this gallery. 


>>> If you have a few minutes, be sure to check out the "Best of" postings.<<<