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Integrator
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Discussion Starter #142 (Edited)
Following Loren's example, I decided to get rid of the antiquated mechanical distributor.
I'm only wondering WHAT TOOK ME SO LONG!

Apparently, the obvious things are not so... obvious.

For the cost and simplicity, the stand-alone MegaJolt-E has no competitors.

Megajolt is a distributor-less ignition system that is fully mappable (using freeware software) via a laptop, allowing the user to program the ignition to fire at any desired angle BTDC, with reference to engine revs and manifold pressure.
More details on Megajolt are available here: Main Page - Autosport Labs

The distributor is, at best, a compromise between power and economy. It relies on centrifugal weights held by springs, with a vacuum advance unit, and these will tire over time giving non standard performance, and these also have mechanical constraints even when perfect. What Megajolt allows is for a decision to made as to the exact ignition advance required in each discrete situation, which is something the distributor with a vacuum advance unit cannot do.
The ignition components are readily and cheaply available from your local junk yard for about 50 bucks as it uses the Ford EDIS (Electronic Distributor-less Ignition System) components that were used in early to mid 90's Sierras, Escorts, Fiestas. The ignition controller can be purchased fully built here Autosport Labs.

The EDIS module monitors crank position and communicates to the ignition controller crank position and revs. The ignition controller (the Megajolt unit) looks to its map, and then communicates to the EDIS module when the spark should be fired. If the ignition controller fails to communicate with the EDIS module, the EDIS module will fire the spark at 10°. This is known as limp home mode, and is a built in feature of the Ford components.

To monitor crank position, some modifications were required. The Ford system uses a variable reluctance sensor against a toothed wheel to know what position the crank is in. The toothed wheel needs to have what is known as 36-1 configuration. That is 36 teeth minus one. The missing tooth signifies to the EDIS unit that number one cylinder is now at 90° BTDC. There are a few solutions to this issue, but all require a VR sensor installing near to the crank pulley looking at a toothed wheel. You may bolt a toothed wheel to the crank pulley, or have teeth machined into the crank pulley flange. I have purchased a bracket and the pulley w/ 36-1 wheel especially made for Lotus by those chaps:

Direct fitment, plug-and-play parts.
http://www.millersmule.com/MillersMuleStore/en/12-lotus-parts

To read more, see this link
http://www.autosportlabs.net/MJLJ_V4_vehicle_installation_guide

Bye, bye old dizzzy!

Thank you Loren!
 

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Here's a picture of the installation over the drivers side fuel tank.
The black box is the controller to the UTCIS-PT which takes care of the digital WUR.
The unit on the firewall is the Ford EDIS module connected to the Megajolt/E. The ignition powered "fused lead" is the red line ( not connected ). The yellow shrink wrap mini board is the tach adapter.
 

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I too am a big fan of crank-fired ignition on the Lotus 9XX motors. I have a detailed 21 page article I have written on fitting EDIS crank-fired ignition to a Lotus 907 motor in my 1974 Jensen-Healey. It includes detailed wiring diagrams, photos and a sample ignition map I am using on my car. I uploaded this 21 page pdf article to the files section of the S1S2S3Owners mailing list on yahoo groups.

BTW, I am also a big fan of converting to electronic fuel injection using the Meagsquirt ECU (which does both EDIS control and EFI control). Particularly when combined with larger throttle bodies than what is normally installed on the naturally aspirated federal cars that had the two 1.75inch ZS carbs. When I did my conversion I used two 2.125inch throttle bodies and opened the ZS manifold up to match them. This works very nicely and makes the car a joy to drive.
 

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Integrator
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Discussion Starter #151
They were out of stock,so I had to wait. Just ordered the processor and cable. Waiting for the pulley and 36-1 wheel. Millers Mule should have them in stock by the beginning of May.

If you have any questions about it - ask Loren. He has done that already.
 

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Integrator
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Discussion Starter #153 (Edited)
Yet another restriction.

84-88 Turbos have a restrictive 48mm turbine port (!).
Port could be opened up to 58mm and the new, larger wheel fitted. Reduction in back pressure is expected to be significant.
With this mod, the recirculation BOV installation is highly recommended to prevent surges.
On the cold side you may attach a hi velocity scroll "foreign" housing ported to “Super 60”, 60trim + enlarged compressor inducer.

BTW: this is the last turbo Busanostra built for X-180 Esprit.

THANK YOU BUSA!
 

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Integrator
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Discussion Starter #156 (Edited)
Adding BOV

Blow off valve reduces turbo back pressure surge. This occurs when the turbo boosts up and then you shut the throttle closed , as in between shifts. Since the turbo never stops spinning so the pressure builds up when,you close off the air flow. That pressure wave travels back to the turbo and slams against the turbo vanes. It can blow up the turbo over time and slows the turbine speed down. Adding a blowoff valve gives the air a place to escape and turbo never does see a large surge. It also alows the turbo to maintian a maximum "spin" so that when you hit the throttle again the boost is already there. It also aids in preventing overboost as an another fail safe.
PLEASE NOTE: On CIS Bosch injected cars the air expelled by the BOV MUST BE RECIRCULATED. It must not be vented out to the atmosphere.
Why?
The air mass is measured by CIS MAF meter at the entrance of the trunking duct. This information is signaled to the Fuel Distributor and corresponding amount of fuel is dispensed by FD. If we vent some air from the plenum we would disrupt Air/Fuel ratio and engine would stall.

I intend to use Greddy FV (improved) valve.
The valve at the picture is a cheap copy used as a mock-up.
 

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While I intend on keeping my car as stock as possible, I am absolutely loving all of the work you're putting into this. Thanks!
 

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Integrator
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Discussion Starter #158 (Edited)
So called "107" cams (last digits of the part number) are advertised as 252° deg duration, 0.378" lift,
ideally with:

........ int . exh
.........22° 50°
.........50° 22°

LSA 104°
ovrlap 44°
int cam adv 0°

However, (per Garry Kemp), if you check with a timing wheel, the results are closer to 260° (perhaps due to all tolerances stack up), which unfavourably affects the overlap.
With 262°/262° duration at 104/104 MOP, the overlap is close to54°.

Higher overlap is a bad news for our turbocharged engines.

However, there is an uncomplicated method to reduce it.
It requires running 106° MOP int and 110°MOP exh, which w/ "107" cams would diminish overlap to 36°. SLA grows to 108° and intake cam center line will advance +2°.

If we go further and use the Excel "104" cam ("hot" cam w/higher lift, 272° duration) on the intake, timed at 106°MOP,
and stock "107" cam on the exh side at 110°MOP (252° advertised duration),
we will be able to achieve relatively small overlap (46°), spread SLA* a bit wider to 108° and advance int cam** by+2°.

Bottom line:
When the lump is out, you should always check your cam timing with the degree wheel. If out of whack - order the adjustable vernier pulleys, do it right.

______*
Increase LSA (lobe separation angle)= good idle, high vacuum, increase power band span (wide rpm range), flatten the torque curve, delay peak torque, but can reduce peak power. A short LSA (more overlap) makes the torque peak and fall early (and rapidly) in the power band, rougher idle, less manifold vacuum, strong mid range power.

______**
Advancing the intake centreline tends to make the torque peak event occur earlier. Although there are always exceptions to any rules, if you advance a camshaft you can expect the torque and power curves to move to the left, with a slight drop in peak power, but a smoother curve.
The way to visualize what happens is for the standard cam without any advance or retard, the rpm versus power/torque curves will not have smooth curves. Advancing the cam will tend to smooth the curve and bias to the left side of the bumps, while retarding will smooth and bias to the right side.
 

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Integrator
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Discussion Starter #159 (Edited)
Following Loren's example, I decided to get rid of the antiquated mechanical distributor.
I'm only wondering WHAT TOOK ME SO LONG!

Apparently, the obvious things are not so... obvious.

For the cost and simplicity, the stand-alone MegaJolt-E has no competitors.

Megajolt is a distributor-less ignition system that is fully mappable (using freeware software) via a laptop, allowing the user to program the ignition to fire at any desired angle BTDC, with reference to engine revs and manifold pressure.
More details on Megajolt are available here: Main Page - Autosport Labs

The distributor is, at best, a compromise between power and economy. It relies on centrifugal weights held by springs, with a vacuum advance unit, and these will tire over time giving non standard performance, and these also have mechanical constraints even when perfect. What Megajolt allows is for a decision to made as to the exact ignition advance required in each discrete situation, which is something the distributor with a vacuum advance unit cannot do.
The ignition components are readily and cheaply available from your local junk yard for about 50 bucks as it uses the Ford EDIS (Electronic Distributor-less Ignition System) components that were used in early to mid 90's Sierras, Escorts, Fiestas. The ignition controller can be purchased fully built here Autosport Labs.

The EDIS module monitors crank position and communicates to the ignition controller crank position and revs. The ignition controller (the Megajolt unit) looks to its map, and then communicates to the EDIS module when the spark should be fired. If the ignition controller fails to communicate with the EDIS module, the EDIS module will fire the spark at 10°. This is known as limp home mode, and is a built in feature of the Ford components.

To monitor crank position, some modifications were required. The Ford system uses a variable reluctance sensor against a toothed wheel to know what position the crank is in. The toothed wheel needs to have what is known as 36-1 configuration. That is 36 teeth minus one. The missing tooth signifies to the EDIS unit that number one cylinder is now at 90° BTDC. There are a few solutions to this issue, but all require a VR sensor installing near to the crank pulley looking at a toothed wheel. You may bolt a toothed wheel to the crank pulley, or have teeth machined into the crank pulley flange. I have purchased a bracket and the pulley w/ 36-1 wheel especially made for Lotus by those chaps:

Direct fitment, plug-and-play parts.
Lotus - Miller's Mule

To read more, see this link
MJLJ V4 vehicle installation guide - Autosport Labs

Bye, bye old dizzzy!

Thank you Loren!
Miller's Mule has replenished the stock and ALL parts are available, including a custom V-belt pulley with 36-1 wheel.

One stop shopping, v.good quality !
 

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