The Jensen Owners' Club A technical and discussion forum for all Jensen enthusiasts It is currently Tue May 21, 2019 11:30 am

V-8 Engine Tech

Mk3 Interceptor: This is my 440 EFI conversion log.

Mopar Big Block Talk

by Philip Lochner » Tue Apr 02, 2013 8:03 am

This is where I will report on the whole EFI conversion process to my '74 Mk3 Interceptor.

"Hind sight is a very exact science"
I have, since doing this conversion, concluded as follows:
1) Doing a transmission conversion that offers 0.7 or lower ratio is by far a more worthier conversion than EFI. Thus rather spend your money on eg. a good 4sp with overdrive 4th transmission than on an EFI conversion;
2) implementing an ECU mapped ignition system is far cheaper and of more value than implementing EFI (if the engine has a well tuned Carter TQ);
3) the Carter Thermoquad is an EXCELLENT carburetor, despite all the negative talk about it. Its only two little O-rings (with an X cross-section profile) which do present issues I have replaced these with readily available O-rings which are working fine. The TQ is unique in that it offers very easy fuel tuning on its primaries (with a small flat screwdriver) as well as on its secondaries (with smallish pliers). If the tuner understands tuning, it is thus very quick and easy to tune a TQ for excellent performance (and "economy").
4) Don't get me wrong, I have no regrets, having EFI is absolute bliss! Combined with the 4sp transmission conversion I implemented on this car, I get 8km/L (12.5L/100km / 18.8mpg US / 22.6mpg UK) on the open road (mostly with A/C on, doing 120km/h - 75mph). I'm just presenting the most cost-effective upgrades if budget is constrained.


I have a pdf document that summarizes the whole EFI conversion which would save you having to read this whole thread. Just send me a private mail with your email address and I'll mail you the document.

PICTURES: Dropbox decided to close their "public folders" which has killed my links to my pics. One day when I have time, I'll upload them to this site again.

Well, 1st step is to buy stuff! The most important of these is the intake manifold. I decided on the (1)Edelbrock Victor 440 due to the possibility of fitting a low boost supercharger later on. I have chosen the Edelbrock 38783 throttle body with the Pulse Width Modulated Idle valve - less troublesome to get it to work than a stepper motor type. A friend in the US is helping me procure all the bits I need.

Next I will first do away with the dissy and replace this with a wasted spark distributorless ignition sytem. This will consist of a 36-1 trigger wheel and VR sensor (magnetic pick-up) being fitted to the crank. I'll be using a Megasquirt-2 ECU (I've done several EFI conversions with MS-2) which can drive 4 ignition outputs for the 4 coils whilst still retaining barometric correction for fuel and timing. I will be using two 4-post coil packs as used in EDIS-8 or EDIS-4 ignition systems. These will most likely be mounted towards the centre rear of the engine. Once the ignition system is working fine, I will proceed with the fuelling side of things.

EDIT (15 Aug 2013):
(1) I have since changed my mind and will get the Edelbrock 7193. The high rpm nature of the Victor as well as its high profile made me change my mind. I would most certainly have had to make a replacement bonnet which MIGHT now not be necessary, even with supercharger.

EDIT (10 Dec 2013)
The EFI conversion is now complete. You can see the finished "product" here: http://www.joc.org.uk/phpBB2/viewtopic.php?f=20&t=15116&start=105#p115189. This is what it looks like now:

Please note:
1) The mechanical link to the A727 transmission has since been deleted with the installation of the GM 4L60e transmission.
2) Having fitted original exhaust manifolds since this picture was taken, the HT wires now run down behind the engine and underneath the manifolds as well as underneath the intake manifold (only possible if the EGR channel is removed) to the front of the engine and then down the front of each bank underneath the exhaust manifold.
tn_DSC_0070.JPG
tn_DSC_0070.JPG (269.01 KiB) Viewed 480 times


tn_DSC_0071.JPG
tn_DSC_0071.JPG (276.33 KiB) Viewed 480 times
Last edited by Philip Lochner on Wed Jan 24, 2018 7:25 am, edited 10 times in total.
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

by azenis » Tue Apr 02, 2013 11:09 pm

I would like to do something similar to mine, so will watch this thread closely. :)
Nigel Honey
Hobart, Australia
Interceptor 3 128/4633
Australian Jensen Forum
User avatar
azenis
 
Posts: 164
Joined: Sat Feb 25, 2006 1:57 pm
Location: Hobart Australia

by Edgar » Wed Apr 03, 2013 11:24 am

I've bookmarked this thread. Really interesting to read about your plans and further progress.

Have you heard about KMS systems? This Dutch based company produces very nice stuff amongst which programmable management systems. Check it out: http://kms.vankronenburg.nl/
A good friend of mine used to have Megasquirt on his highly modified Esccort (supercharged Scorpio Cosworth engine + 4x4 setup) but switched to KMS. It seems to be more user-friendly, highly adaptable and reliable.

Also heard of kdFi? http://www.k-data.org/kdfi-1-4.html
Sort of full-option Megasquirt clone.
1973 Interceptor Mk. III
1974 Interceptor Mk. III Convertible
1976 Jensen GT
TVR Cerbera
E-type OTS
Triumph TR3A
Jensens: prepare for the worst and hope for the best
User avatar
Edgar
 
Posts: 802
Joined: Mon Jan 25, 2010 6:20 pm
Location: The Netherlands

by Philip Lochner » Wed Apr 03, 2013 11:52 am

Thanks for those links Edgar! Never heard of them, but very interesting.

If the KMS is running MSExtra firmware I can not understand how it can be any easier than MS proper. I do like the more professional hardware but on the other hand, with my electronic background, I really enjoy being able to populate the MS V3 PCB from the ground up and then test the circuits as I go along.

I have the MS hardware already and will be building and reporting on this while I wait for the EFI hardware to be delivered. Also, I can proceed with fitting the trigger wheel and the VR sensor.

The car is not parked at my home yet (no space) so I have to move the V12 Cobra away in order to be able to work on the Jensen.
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

by glenn999 » Wed Apr 03, 2013 7:12 pm

Verify the hood clearance before spending cash. The victor intake is tall.
glenn999
 
Posts: 19
Joined: Thu Sep 09, 2010 12:51 pm
Location: Göteborg, Sweden

by Steve Payne » Wed Apr 03, 2013 9:12 pm

Something you need to remember these engines are very primative.

Get the spark to fire as early as possible, because of the primitive combustion chamber design an early spark makes them run a lot better. Will MS run a knock sensor?

Dont go to lean even on cruise or your engine temp will go sky high. The cooling system is marginal and struggles with high combustion chamber temps.

To get a good strong idle you will need to run richer than you would think. I have seen some of these 440's need 13 to 1 to get the best idle.

Steve
JOC official Lightning engineer
User avatar
Steve Payne
MASSIVE RED CARD
MASSIVE RED CARD
 
Posts: 5124
Joined: Thu Nov 17, 2005 4:51 pm
Location: Witney , Oxfordshire

by jglarkin » Wed Apr 03, 2013 10:26 pm

Is this of any interest? Looks pretty straightforward.

http://www.atomicefi.com/home.aspx

Jon.
Last edited by jglarkin on Wed Apr 03, 2013 10:35 pm, edited 1 time in total.
Jon
C-V8 112-2355

More Gas => More Wind
https://www.flickr.com/photos/62752698@N06/albums "The renovation story" (a large collection of pictures of a rotten car).
User avatar
jglarkin
 
Posts: 584
Joined: Thu Feb 04, 2010 6:54 pm
Location: Rochester Kent

by Steve Payne » Wed Apr 03, 2013 10:34 pm

No ignition control.

Just controlling the fuel will hardly be any better than a good carb.

With control of the ignition system it makes it a big difference.

Steve
JOC official Lightning engineer
User avatar
Steve Payne
MASSIVE RED CARD
MASSIVE RED CARD
 
Posts: 5124
Joined: Thu Nov 17, 2005 4:51 pm
Location: Witney , Oxfordshire

by jglarkin » Wed Apr 03, 2013 11:13 pm

Some control, probably not as much as you would like.

http://www.atomicefi.com/Diagrams.aspx
http://www.atomicefi.com/AtomicFAQ.aspx

Some folks like the challenge of infinite control and sophistication, some of us just like the damn thing to fire up and go!
Jon
C-V8 112-2355

More Gas => More Wind
https://www.flickr.com/photos/62752698@N06/albums "The renovation story" (a large collection of pictures of a rotten car).
User avatar
jglarkin
 
Posts: 584
Joined: Thu Feb 04, 2010 6:54 pm
Location: Rochester Kent

by DPP » Thu Apr 04, 2013 5:22 am

Just out of interest as I will be staying with a carb but what sort of extra mpg would you hope for on a well set up system.
Dave
Jensen FF 119/133
Jensen Interceptor III 128/4430
Princess 2 2200HLS
User avatar
DPP
 
Posts: 1013
Joined: Thu Sep 29, 2011 12:03 pm
Location: Cornwall

by Philip Lochner » Thu Apr 04, 2013 5:53 am

glenn999 wrote:Verify the hood clearance before spending cash. The victor intake is tall.


Thanks for the heads up Glenn. Yes, I'm aware that there might be issues. I have a friend who is highly competent with GRP and Carbon Fiber. My plan is to give him the current bonnet as template so he can make me another from which I will simply cut a hole for the air filter to clear and then he will make a scoop to cover that once we know how much clearance is needed. (I would very much like to fit the supercharger later on as well....)

I'm also eyeing those side gills. Would be very nice if I could find a way to route cool air from those to an air filter on either side of the engine and then route that through a Y feed into the throttle body using a low profile inverted bowl on top of the throttle body.... The wiper motor on the LHS appears to be in the way though. If I could get this to work, I might be able to retain the original bonnet (preferred).
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

by Philip Lochner » Thu Apr 04, 2013 6:15 am

Steve Payne wrote:Something you need to remember these engines are very primitive.

Get the spark to fire as early as possible, because of the primitive combustion chamber design an early spark makes them run a lot better. Will MS run a knock sensor?


I doubt that the 440 is any more primitive than the Rover V8s (on which I have much experience) which came into existence as the Buick 215 in the early 60s? MS does provide for a knock sensor but when you read the documentation on that it is very clear that one should be very careful to rely too much on knock sensing. In any event, this 440 is a low compression engine and it will be very hard to induce knock on this engine. Also, I prefer to tune my MS systems to run well tuned in "open loop" on both fuel and timing under all conditions, thus eliminating the problems that may arise if the lambda sensor or knock sensor should fail.

I did install MS on a friend's Discovery 1 3.9 low compression (8.35:1) and was amazed at how much advance this engine asked for. This was the only car where I tuned timing on a braked dyno - because one can not rely on detonation / knocing / pinging to tell you when you have advanced too much due to the low compression.


Steve Payne wrote: Dont go to lean even on cruise or your engine temp will go sky high. The cooling system is marginal and struggles with high combustion chamber temps.


I'll keep a close eye on matters, thanks Steve. Again I will draw on my experience on my Rovers and Jaguars. I did not find that there was any relation between AFRs and engine temps on either my Landies or my V12 Jags. But the 440 may indeed prove different. My one Rover V8 cruises at 16.5:1 where many would cry: "You are going to burn the valves!!!" My E-type (running an HE V12 engine) cruises at 17.5:1 !!!

The marginal cooling comes through loud and clear when one starts reading up on the Jensen. So far my experience is quite the contrary BUT I do not have the condenser fitted yet and thus AC is not providing any restriction or pre-heating of the air passing through the radiator.

Steve Payne wrote:To get a good strong idle you will need to run richer than you would think. I have seen some of these 440's need 13 to 1 to get the best idle.


This does not surprise me. My Rovers and even the HE V12s (HE = Michael May Fireball comubstion chambers) do not like to idle at anything leaner than 13.5. I have learnt that an engine "talks" to its tuner, telling you when its not happy. Sometimes I find myself somewhat hard of hearing though :lol:
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

by Philip Lochner » Thu Apr 04, 2013 6:58 am

jglarkin wrote:Is this of any interest? Looks pretty straightforward.

http://www.atomicefi.com/home.aspx

Jon.


Jon, I did consider TBI (Throttle body injection). Going with TBI would offer the benefit of being able to retain the current intake manifold and of course should not result in any bonnet clearing issues.

But here's the reason why I don't want to go that route: With TBI, you have 4 injectors doing the work that 8 injectors would with port injection. This is similar to fitting injectors that are too large for a particular engine. What happens then is that at idle and at light throttle conditions (steady cruising), the injector pulsewidths become so short that the DIFFERENCES in the amounts of fuel being delivered between the injectors results in widely varying AFRs resulting from the barrel being fed by each injector. The only way to overcome this issue is then to run each barrel rather rich (for longer pulsewidths and lesser fuelling differences) and there goes one of the major benefits of EFI.

If however, this MSD TBI has been fitted with very high quality injectors that offer very similar fuel flow at very short pulsewidths, it could actually be a very attractive solution.
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

by Philip Lochner » Thu Apr 04, 2013 7:05 am

jglarkin wrote:Some control, probably not as much as you would like.


In my mind it is hardly worth going EFI and then not do away with the dissy. The reason they are limited in ignition control is because they retain the dissy (which limits the amount of advance* one can have).

But one could still buy the Throttle body and then use any other ECU to control it which would then also offer distributorless and fully mapped ignition.

* My E-type cruises for miles on end with 50degs advance running at 17.5:1 AFR.
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

by Philip Lochner » Thu Apr 04, 2013 7:12 am

DPP wrote:Just out of interest as I will be staying with a carb but what sort of extra mpg would you hope for on a well set up system.


Whilst I do hope for an improvement in mpg, my main consideration is optimization. I just have a thing about running things optimally. Once my car is running well on its dissy/carb setup, I intend doing a consumption benchmark(http://www.joc.org.uk/phpBB2/viewtopic.php?f=4&t=15865) to see what it does at present. Then I would dare to make a call on target mpg.

BUT, mpg depends more on gearing than it does on fuelling/timing in my unqualified opinion. My '80 XJS is a good example. This car has a so-called pre-HE engine, notorious for bad mpg. I have fitted my MS + distributorless system to this car but I have also fitted a 5sp manual conversion to the car which brought the cruising RPMs down from just under 3000rpm to 2000rpm. I believe (unproven) that the change in gearing has done much more for the car's consumption than the EFI upgrade.
Last edited by Philip Lochner on Thu Aug 15, 2013 4:23 pm, edited 1 time in total.
Best regards
Philip
Mk3 7.2 #128/8120 Jan 73 http://tinyurl.com/hsjucm5
Mk3 7.2 #2240.9677 May '74 modified:
Fuel injected: http://tinyurl.com/qyrx93f
GM 4L60e 4-sp transmission: http://tinyurl.com/qxlwk95
User avatar
Philip Lochner
 
Posts: 1228
Joined: Thu Feb 28, 2013 12:29 am
Location: Pretoria, South Africa

Next

Return to V-8 Engine Tech