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Jenvey ITBs And Megasquirt



blog-0096479001391372074.jpgThis sub-project was a case of "because it's there". I'm not a seasoned mechanic by any means so this was definitely a challenge for me, but that was half the fun. I know which is the business end of a spanner/wrench, but this was a major escalation in terms of goals. I learnt a lot in the process, and made mistakes. It has been very satisfying to pull it all together.

It started as a complete front suspension and steering rebuild, and snowballed from there. As I was dropping the subframe anyway, I decided the motor and trans would come out too for a cosmetic clean up. The dual DCOE carbs were leaking, so I was going to rebuild them too. Then I started reading about everyone else's EFI conversions, particularly this one:



Mmmmm. Jenvey. So shiny. So purposeful looking. Throw in better MPG, increased tunability and more power. Hell, why not do Jenvey ITBs and Megasquirt "while I'm in there". I could get rid of the pod filters too which always annoyed me, and install some other air filter system.


Here is what was addressed in this project:

  • Convert from twin DCOEs to Jenvey ITBs
  • Install Megasquirt and associated sensors: coolant and air temp, MAP, TPS, O2
  • Convert from Crane Fireball XR3000 ignition to crank fired EDIS ignition
  • Run hard fuel lines including a return
  • Replace the Carter external electric fuel pump with an in tank unit
  • Install a fuel pressure regulator
  • Install a large capacity fuel filter
  • Replace ball joints
  • Replace tie rods
  • Replace center link
  • Replace steering disc
  • Replace engine mounts
  • Replace strut top bearings
  • New coil, spark plugs and plug wires
  • Replace steering idler arm bushing (total b!tch of a project in itself)
  • Replace soft clutch line with a stainless steel line
  • Replace transmission mount
  • Rebuilt shifter platform
  • Install missing shift foam ring
  • Rehang exhaust and finish exhaust support bracket properly
  • Weld in subframe reinforcement for engine mount
  • Re-wire Hella driving lights with a proper fuse and relay arrangement
  • Re-wire electric fan to be controlled by Megasquirt
  • Install higher output alternator to support EFI/Megasquirt
  • Remove voltage regulator
  • Install new starter
  • Clean up engine bay wiring and re-wrap it
  • Paint the oil pan, valve cover, intake manifold, subframe, strut housings, water neck, shifter platform, and pulley
  • Clean the engine and transmission
  • Install missing flywheel inspection cover
  • Figure out a more effective and visually pleasing air filter
  • Fit front strut brace


This was the starting point:



I took the car off the road and dropped the engine and transmission in the autumn of 2012, and started accumulating parts...



...and then promptly lost motivation. Didn't really make any progress through the summer of 2013 but got reinvigorated after going on the "Fall Tour" with the other Minnesota 02ers. I had to drive my Porsche that day, and it was a sad day.



Once I got back into it, cleaning was slow and labourious, so I made the most of it with frequent refreshments:



Test fitting the new 95AMP alternator from BNR:



Prior to this project the engine always rocked violently which was disconcerting. Engine mounted were standard rubber units, and have been replaced with urethane. I did find one of the mounting brackets had snapped, so that was replaced also:



I compartmentalized the project, and concentrated on the subframe, steering and suspension first. Here is how it looked when it came off the car:






Reassembly was pretty straightforward except for the steering idler arm bushing. Another "jigsaw" pic:



Although there were no cracks, I reinforced the subframe:



Everything was either brand new or blasted and powder coated:




It's an early car so the blue plastic steering idler arm bushings available today do not fit (too fat). W&N claimed to have the right part for the early cars, but when they arrive from Germany the diameter was correct but the length was too long.

W&N bushings (expensive and not the right size!):




Note one of the new style blue bushings bashed into place, since removed:



I dug around in my spares and found some urethane bushings that were a close fit so it looked at the manufacturers website to see what other sizes they had:



...and I found these on sale for $10:



...and they fit like a glove:




Very satisfying the have it all freshened up:







Then I moved on to the ITBs and Megasquirt.

I spent a small fortune at Jenvey (actually through the very helpful people at Burton Power - a must see website for any fans of Euro-Ford products) on the following:

  • ITBs
  • TPS
  • TPS connector
  • Throttle linkage
  • Throttle linkage bracket
  • Air horns x4
  • Vacuum manifold and hose
  • Fuel rail
  • Fuel pressure regulator
  • Air horn spacers


Instead of getting ITBs the same length as the DCOEs, I got the 91mm length ITBs to give me more room between the end of the ITBs and the brake booster:



What about the reduced intake runner length? Well, I hope to solve that with my air filter set up. More on that later. I looked at many many filter options from Reverie, Pipercross, ITG, etc., but none really met my needs. The new alternator is deeper than the old one and the proximity of the built in voltage regulator to the end of the ITBs doesn't allow you to fit a filter baseplate to the end of the ITBs. I considered running mesh filters on the air horns once I found some in the right size (59mm diameter) but it can get dusty around here in the summer.


These are the ITBs, with the fuel rail yet to be cut to size, and also with standard size injectors.






Some idiot who seems pleased with his new toys:



Once fitted, I wasn't happy about the mating surface between the ITBs and the intake manifolds, so I found some appropriately sized DCOE pattern spacers that also had o-rings built in. See them in this test fitting:



Also note the use of pico sized injectors to ensure the fuel rail does not protrude beyond the end of the ITBs. This was so I could use a Pipercross PX600 baseplate, but notice the very tight space between the voltage regulator and the intake on cylinder #1.



Spacers can be seen better in this shot:



Here is the toothed wheel on the crank with the sensor test fitted:



Out of pure vanity I wanted the throttle control to be under the ITBs, and Jenvey supplied a very versatile unit. Unfortunately it was too deep and interfered with the original starter, so I had to buy a new smaller starter to get it to all fit under there:





At this point, the engine was petty much ready to back in. I mated the engine and trans to the subframe:







Much more progress has been made than shown here, but I will save that for a later post.







Edited by stuff
remove spurious images

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Could you please provide a complete part list (and $) for the ITB portion of the project? I am thinking of ditching the DCOEs I have and need to know how much I need to borrow from the CFO / wife :) to make this happen.


BTW how much space will you have between the brake booster and the filters?


Awesome project BTW!!


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With the Cannon manifold, 6mm spacers, 91mm ITBs, I am left with approx 85mm between the booster and the end of the ITB without airhorns or filter:


This will give you a clue about possible filter ideas:


ITB cost (does not include shipping from Jenvey in England, or Burton Power)... cut and paste on phone... Sorry about formatting:



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Hi Tom,

This is what I was going to buy:

Silicone hose, ID=51mm/2.00", OD=59mm/2.32" OD, 45deg elbow

Part #: HPS HTSEC45-200-BLK


...until I realized that I didn't want to spend a ridiculous amount of money on hoses! Got some cheap and cheerful copies from a vendor called Auto Dynasty on amazon instead, and they are probably available on ebay too:


The cheap ones are very "sticky", so dirt or dust readily sticks to the exterior but they serve the purpose well. Easily stiff enough to support the weight of of the filter and airhorns.

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Awesome project.  I have a 'spare' 1602 and would love to do something along these lines to it...eventually !! 


I am also a 'Amateur' (capital A) mechanic.  On a scale of 1 - 10, I am probably a 6.


On a scale of 1 - 10 what would be your skills and on a similar scale how difficult would you rate this as a DIY project ?




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Hi Wayne,

I probably started the project as a "4" mechanic and will end as a "6" ;-)

Difficulty is all relative. Research on part compatibility was difficult as there is no single recipe to follow so sometimes you have to purchase some items without knowing if they will fit/work correctly. Bolting everything together is the fun part and not especially difficult. Resolving issues or unexpected results after installation can be frustrating, and that's where the real learning occurs in my project - during troubleshooting. Apart from fabbing a bracket for the throttle cable from bicycle parts and junk from around my garage, I haven't had to fabricate anything serious so, apart from an engine hoist, I have been able to do everything with typical hand tools that car enthusiasts usually have.

Time... this has taken much longer than expected, so be prepared for that. Like a whole year. Procrastination is a significant factor, but even the simplest jobs take me a while as I am by my own admission frustratingly methodical and safe.

Do it. It's rewarding :-)



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