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Re: 1972 Nail Project

PostPosted: Mon Aug 25, 2014 10:19 pm
by 1972nail
Thanks guys for the comments. :D
Haven't got my copy yet but I believe it has taken up 7 pages!

Re: 1972 Nail Project

PostPosted: Thu Aug 28, 2014 11:09 pm
by 1972nail
I started this thread a few years ago with a photoshopped concept image. I think it's about time to update that image with the real life car.

Re: 1972 Nail Project

PostPosted: Fri Aug 29, 2014 7:23 am
by Colin
This is a marvellous Firenza beautifully restored and tastefully modified. The colour really suits the shape with those original sportpart wings. I think the real thing has turned out looking better than the photoshop image design concept. Super cool car! 8)

Re: 1972 Nail Project

PostPosted: Fri Aug 29, 2014 7:33 pm
by 1972nail
Thanks Colin. :D

Re: 1972 Nail Project

PostPosted: Tue Mar 27, 2018 4:00 pm
by 1972nail
Well it's about time I got moving on with my original plans for this car. My original intention was to build it as I would have done back in the 80's and then after a few years of running it like that start to progressively modify it using period parts right through to a full modern management and EFI. So, I'm starting to plan the approach and direction I want to go.

My car is built using period parts and looks like it could have been built in the 1970's or 80's and I want to keep any modifications as subtle as possible. I've been planning this for a few years so have a good idea of what way I want to proceed and I've gathered together some of the hardware.

I will probably be using a single 48mm throttle body with an home made alloy plenum style manifold, adapted from an MGF, complete with MAP sensor, injectors, fuel rail, pressure regulator and various attached sensors, a Bedford CF Bosch JHFU4 Hall effect distributor with a Bosch '008' type (Intermotor 150000) ignition amp and matching Bosch coil.

At the minute I think that a semi sequential injection configuration would be best suited as the injectors will be mounted quite far away from the valves and injector timing will not be so critical. But a 2 channel injector board will limit my options if I choose to go fully sequential for some reason.

The object of this build will be to do it on the cheap, do as much as I can myself, to keep the installation quite discrete and do something different from the norm. This route rules out the now quite common 'Jenvey' style individual throttle bodies.

I've looked at the Patton Engineering Stromberg carb injector conversion kits which are super discrete but those are quite expensive and the Strombergs are very restrictive and won't flow enough air for future tuning options.

All this will be managed using a DIY ECU. The Megasquirt system is the best known of these but the design is now quite old and kits are becoming expensive for what you get. I'm considering the Speeduino ECU which is still very much in the development stage but already looks very promising and relatively cheap too.

I've already been running the CF distributor for a few months and it really needs the advance curve altered to make the engine run really well. This is what has prompted me to get moving on this as the ECU kit and software will give me programmable ignition straight off for less than the price of a mechanical re-curve.

Re: 1972 Nail Project

PostPosted: Tue Mar 27, 2018 6:27 pm
by droopsnoot
I'll be keeping an eye on this, some of those are things that I'd like to add to mine. I hadn't heard of the Speeduino, presumably that's based on the Arduino system and might be a nice alternative.

Re: 1972 Nail Project

PostPosted: Tue Mar 27, 2018 7:12 pm
by 1972nail
Yes, based on the Arduino. The throttle body I'm using is a 4 bolt mounting design and an almost straight swap for a single 1.75 Stromberg onto a Sromberg manifold. The single Stromberg manifold is a small plenum type design and may be suitable for fitting two injectors directly into the 'Y' piece of the inlet runners.....

Re: 1972 Nail Project

PostPosted: Fri Mar 30, 2018 5:12 pm
by 1972nail
A few further thoughts on the management installation. I'm going to control the spark first off as it is relatively easy without too much fabrication. My original intention was to use the Bedford CF Bosch distributor set up I have and use it to inform the ECU when to fire the coil and this is easy enough to sort out. The distributor will need the advance mechanisms locked up or disabled, thus destroying a really sought after conversion kit. :cry:

So this got me thinking.....does it have use the rare and sought after CF distributor? Well not really, a standard Delco with the mechanical and vacuum advance disabled and fitted with an Accuspark module will do the same job. The main problem with the Delco distributors are they tend to wear the advance mechanism quite badly and the points are not very stable at higher revs, giving poor ignition control above 3000 rpm. Replacing the points with an Accuspark solves half the problem and adding ECU controlled timing solves the rest. :idea:

A quick consultation with my EFI gurus on another forum and yes, the Accuspark module will be a more suitable trigger as it will provide an easier signal to manage...happy days 8). I'll just need a suitable coil and amplifier, again I could use the Bosch one but it would be better kept with the distributor as they are hard to find too, or I could use a VW Polo 6N type .....£17 - £25 for a new one on ebay.

Yes, I could go completely 'distrubutorless' with a multiple coil setup. But then that will not look as original or discrete as using one coil firing through an original distributor.

I'll be inviting offers for the Bosch distributor set up soon.... :)

Re: 1972 Nail Project

PostPosted: Wed Apr 04, 2018 9:08 pm
by 1972nail
I stripped an old Delco distributor today to see what the potential of using it for the conversion is.

In a mechanical distributor the relationship of distributor drive, the rotor arm and the switching mechanism which fires the coil, is altered by the vacuum and mechanical advance system, thus firing the coil when the point of the rotor is aligned with the plug lead outlet on the cap. This is not so in a programmable system where the advance is altered electronically but the rotor arm and sensor are both fixed to the drive, so the spark can arrive at the end of the arm before or after it passes the plug lead outlet, causing a misfire.

The trick is to time the distributor so that the rotor aligns with the plug lead outlet at the mid way point between minimum and maximum advance angle programmed into the ECU. Then set the trigger, be it traditional points or a Hall sensor, to send the trigger instruction to ECU at or just before the minimum timing, the ECU then delays firing the coil until the programmed advance is reached at that particular engine speed and load. Hopefully the leading edge of the rotor arm aligns with the plug lead at the maximum advance point and the trailing edge aligns at the minimum advance point. This is called 'rotor phasing'

On most distributors this means that the drive of the distributor and/or the rotor arm need to be altered and then locked in their new positions. On the Bedford CF Bosch electronic distributor this means major surgery and permanently altering it to make it work. This would render it useless for any other application, something which I don't want to do on such a desirable period modification piece.

The Delco unit, on the other hand, can be phased extremely easily by removing the vacuum unit completely and just rotating the points/trigger base plate to the required location and screwing it down with a self tapper through the base of the distributor body to fix it in place.......happy days!

The mechanical advance weights need to be removed of course and the mechanism fixed. Just refitting the springs without the weights will be sufficient but you could add a spot of weld if you wish.

Next step? - buy an Accuspark module.

Re: 1972 Nail Project

PostPosted: Thu Apr 05, 2018 7:58 am
by lord13
I have read your last few posts with interest and it has got me thinking, I had a look at the Patton machine site and it all looks very interesting. I especially like the carb covers he does, very neat.

IN regards to the carb conversion with dual phase injectors for the twin strombergs, you could just convert the carbs to plain throttle bodies, with a bit of smoothing and removal of extraneous parts, then use a common rail 4 point injection system and drill into the manifold and mount the injectors there. Then use a wasted spark twin coil unit, say from a cavalier or vectra , with a crank trigger and fabricated mount. The ecu could be one from a late 2.2 ecotec as these have a basic map built in but 'read' the engine and adjust to driving style etc so could possibly adjust itself to the 2.3 quite nicely. Or spend a little on the ecu and get either a stand alone system, or there is a company that do 'piggy back' systems that work with the stock ecu 'somehow' and allow you to program your own maps into them. All this could be done for very little money, I think...just musing here but it has potential I believe... I'm not that clued up on injection systems but have been toying with the idea of an SPI system to fit to the old OHV, I'm thinking along the lines of a corsa 1.2 set up . . . .

Please feel free to 'shoot me down' if I am talking rubbish ok :D :D :D I just think it doesn't NEED to be so complicated, the banger boys next door do this sort of thing all the time :D