Classic Retrofit CDI+: very happy customer

[Sun888]

note to self: next time: search threads first, then post. Not the other way round.

http://www.early911sregistry.org/for...t=Partsklassik

[Jonny Retrofit]

Hi, Jonny here from Classic Retrofit.

The CDI+ unit was conceived almost three years ago. My background is aerospace/medical/industrial real time control systems. We have applied the same rigor to the design of the CDI+ to address a number of shortcomings of the Bosch unit (over voltage protection, short circuit protection etc). I'll spare you the details as they are all in the technical manual on our website www.classicretrofit.com.

The units have been bench and road tested for the equivalent of well over 200,000 road miles. We have worked closely with Historika and Neil Bainbridge to refine and prove the product. The product has been tested on both road and race cars.

We are the only CDI replacement on the market that is dyno proven to give more power without changing the timing. The tests were conducted in a fully balanced engine test cell and the dyno report is available on our website.

We have a number of unique features including soft, hard and launch control rev limiters, shift light output and tacho calibration. Plus programmable MFI fuel cut feature, input delay compensation, second spark timing adjustment etc.

Of course, the units are fully programmable with a custom ignition map which can operate with a standard distributor in overlay mode or a locked one offering full control of the timing.

Yes, we are at the top end of the market. The units are high quality, built and hand assembled in the UK. we offer a 3 year guarantee.

Our test and development programme has involved some of the top names in the 911 World who are now endorsing the product.

We can offer units in a CNC machined case or rehouse our electronics in the original Bosch case on an exchange basis.

Cheers,

Jonny

[72targa]

Neat story...thanks for posting.

Hi,

This is my first post on this forum as Chris said he'd put some feedback here about our new ignition unit which we're calling CDI+. So I thought I'd introduce myself, hope that's ok?

The story started 3 years ago with the restoration of my 911SC. I wanted a car I could use everyday, with every part either restored or replaced with new. I discovered the Bosch CDI box was a part that could only be repaired or replaced with aftermarket parts that were not a plug in replacement or had poor reviews.

My company designs real time control systems (aerospace/medical/industrial) so we used our knowledge and resources to develop a plug and play replacement unit. The emphasis being on quality and robustness. Our design addresses several shortfalls in the Bosch design ( lack of over voltage and short circuit protection for example). There is a technical manual on our website that describes all this so I'll spare the details.

We sent units out for evaluation with a few of the specialists here in the UK. Historika were the first to notice that the engine pickup and throttle response of their 2 litre race car was noticeably 'crisper'. A few rolling road sessions later and the performance gains kept coming. As the CDI+ has a fully mappable ignition curve, the cars were dialled in on the rollers. At the time, we put performance gains down to changing the advance map, but there's more....

We had five or six reports come back along the same lines as Chris's post above. More power, hesitation cured, smoother etc. On enquiry, these guys had not changed the timing yet. So what was happening?

A side effect of our electronics design, results in two sparks being generated instead of one. We can program the time between the sparks so that the second one occurs mid fuel burn but still well before TDC. This results in more fuel being burnt which produces more power. Well, that was the idea anyway!

Snake Oil!! We've all seen our fair share of 'wonder' products! Was this a fluke? Who are we kidding? How can we prove it?

Enter Neil Bainbridge, a highly respected UK 911 engine builder who just happens to have a fully balanced engine test cell. Neil had a freshly built 2.4T setup for back to back comparisons of CDI+ vs the Bosch unit. The full dyno report is on the CDI+ page of our website. The headlines are 5 to 10 ft-lbs increase of torque right up to 6200RPM.

That's all for now as its late here. Any questions, fire away!

Cheers,

Jonny

[304065]

We are the only CDI replacement on the market that is dyno proven to give more power without changing the timing. The tests were conducted in a fully balanced engine test cell and the dyno report is available on our website.

Can you please explain, in as much detail as you would like, the reason for this power increase?

[Jonny Retrofit]

In a nutshell, the CDI+ produces two sparks for every ignition pulse. The second spark still occurs well before TDC so any unburnt fuel is ignited. We have shown in an engine test cell, that more fuel is burnt using our system, compared to stock, hence more power is produced.

Multi spark ignition systems are not a new idea and are proven to maximise fuel burn. What is new is that we can provide two sparks across the entire RPM range. Most multi spark ignitions (including the most 'popular' US brand)' revert to a single spark beyond 3000RPM.

In addition, our capacitor charge time has been matched to the characteristics of the Bosch coil, meaning that the second spark is still 'useful' at high RPM as it can occur well before TD . What I mean here is that some brands who 'over egg' their primary coil voltage end up taking a long time to charge, by which point the second spark is so late, it is beyond TDC and therefore useless. Sometime less is more.

[Jonny Retrofit]

Nice feedback from today, car is a stock 1970 2.2T :

<iframe width="420" height="315" src="https://www.youtube.com/embed/imv48ECYzWc" frameborder="0" allowfullscreen></iframe>

[Jonny Retrofit]

We sent a couple of CDI+ units out to the States a few months ago now. One to Dave at TRE Motorsport and another to Steve Weiner at RennsportSystems.

Dave ended up sending a unit on to Loren Beggs of 911Design in Montclair, CA. http://nine11design.com/ as he had a '69S being restored with a fresh MFI engine. The engine is rebuilt but totally stock.



I got the impression that Loren is a busy chap so five months later (two days ago) I received an email from Loren:

We ran the car on the dyno and tuned it 1 degree at a time for maximum power with the old CD box. We then installed the Classis Retrofit box. We installed and we did not advance the timing and it would not accelerate past 3000 RPM as the timing was too retarded (as you stated it would be) I just wanted to check it right from the beginning. In the end I think we added 6 or 8 degrees (I’ll find out for sure) and low and behold it added 5-7 HP and 5-7 foot pounds of torque all the way up to 6800 RPM’s at that point it looks and felt like a rev limiter kicked in. I am going to take the instructions home tonight and read some more. Then I’ll get the software loaded on my laptop so I can see what is happening at that RPM point. So needless to say I am pretty excited about the unit. I’ll follow up after doing a little more programing.

So he did some bedtime reading, next day did a few timing tweaks and came back with a whole load of plots. I have overlayed them all in photoshop to the best of my abilities:

With the stock timing:

Thin green and thin blue are Bosch CDI.
Thick green and thick blue are Classic Retrofit CDI+.

Red and purple are CDI+ with the ignition mapped:



He's gonna report back after he takes it out for a drive.

[NorthernThrux]

Impressive I have to say. And nicely done comparisons by independent sources. I'll keep you on the radar whenever my car finally comes back to me.

Have you looked at the timing curves over a variety of the same engines and seen if they are similar, i.e. is their a characteristic curve that you could preload if you knew it was for a '73S vs (say) a '72T that would get you 80% of the power benefit from the right advance without having to set on a dyno?

Ravi

[Jonny Retrofit]

Impressive I have to say. And nicely done comparisons by independent sources. I'll keep you on the radar whenever my car finally comes back to me.

Have you looked at the timing curves over a variety of the same engines and seen if they are similar, i.e. is their a characteristic curve that you could preload if you knew it was for a '73S vs (say) a '72T that would get you 80% of the power benefit from the right advance without having to set on a dyno?

Ravi

Hi Ravi,

That is exactly what we are trying to do. We're trying to dyno the complete CDI car model range - '69 to '89. Ultimately, we should be able to offer downloadable proven maps from our website. The more people we get on board, the better it becomes for all of us!