Jenvey ITBs

[rug]

Today I decided to start my conversion to fuel injection. The car is a 71 coupe with a 1608 engine. It does have weber IDFs on them and some have said it's a waste of time converting to FI. For performance it might be but I like the challange and I have always wanted jenveys... I want to have the car back running for may 1st. That's when we have the first large car meet. Seems like there should be plenty of time but time is limited when you have a family which don't like when you spend all your waken time in the garage.

Began by removing the carbs. Someone built their own air cleaner for this car at some point. Don't have the original and this one has all kinds of sins when you start taking it apart. For one, the filter does not seal all the way around. Second, it is not tall enough. There was about 1 cm between the IDF horns and the top of the air cleaner.



Found some more "mods". Not a carb guy so don't know what this hose is fore but I don't think this is the proper way to close of a hose...



So, trial fited the jenveys. They fit and match the manifold perfectly. Had to shorten then connector for the butterflies between the bodies because they are so close together but no big deal. I will have to make a new bracket for the throttle cable as it will not work with the jenveys. Had to se what it looked like with the airhorns on. yummy....



That's it for today. Next up - a bunch of wiring!

/Carl

[aj81spider]

I'll be following this with interest. What Jenvey's did you buy? I'm interested in what part numbers you got and why you made those selections. I'm thinking about doing what you are doing and any insight into what and how you selected things would be really helpful.

[rug]

I got the 40mm "IDF style" throttle bodies (part # TFP40i). Since I have a 1600 motor I figured 40mm should be plenty large. They are also available in 42 and 45 as well so should be no problem matching whatever output you're aiming for. I got these because they are a direct replacement for the stock weber IDFs. Therefor I can reuse the stock manifold. I couldn't find much info about this kind of conversion for the twin cam engines so my work so far i all based on educated guesses

Also ordered air horns (AH40X40), 330cc pico injectors (IN47/330), fuel rail (TBR32), regulator (WFR024, RH01) and TPS (TP1) from jenvey.

/Carl

[redcars]

What controller are you going to use, and are you going to control the spark also?

[rug]

What controller are you going to use, and are you going to control the spark also?

I will be using a Microsquirt. I've used megasquirt on other cars with good results (but not with ITBs...). I want to do spark as well but for now I will focus on fuel and take RPM-input from the coil. When I get the car back in working order I will look into getting a trigger wheel mounted on the crank pulley.

/Carl

[76124]

Very interested in this project. I have a bare waffletop I have been saving for just this. I've done the IDFs before, but would love the around town drivability of ITBs. Keep us posted!

Thanks

[rug]

Some parts are still stuck in customs... so only thing I can do is figure out where to mount everything. I made some prototypes for airboxes and the only one that fits unless I build my own is the ITG trumpet tray with a JC50 filter. I printed the trumpet tray on my 3d printer to see if it fits. The one mounting tab hits the firewall slightly but I think I can make it work. Pipercross KK600 is way to large (I think this is the same as jenveys airfilter), and I think their smaller one KK500 is too small for my trumpets.



Hopefully the microsquirt arrives this week so I can get the wiring started. Found a hole in the firewall that I think is large enough for all the wires. Feels nice not to have to drill extra holes...

One question is are the stock fuel lines are large enough? The supply line is 8mm OD and the return is tiny at 5mm OD. Would be nice not having to run new lines...

Does anyone know the thread size of the stock vaccum port on the side of the waffle manifold? Need to get a plug for this.

/Carl

[rug]

Small update:

Got most of the parts I need but everything is taking longer than I expect. The wife doesn't like that I spend all my free time in the garage as well

The size for the vacuum port on the intake manifold for the brake booster is a tapered M14x1.5. I found an aluminium plug that fits nicely.

Started wiring everything. The microsquirt and new fuses/relays are located in the driver side behind a speaker box the previous owner installed.




Driver side of the engine bay is all wired up. Everything but the wideband controller and the future ignition coil is on the driver side. MAP sensor and vacuum log is mounted on the side/under the intake manifold.



Passenger side wiring is being worked on this week.
Trying to find a friend with a welder so I can get the O2 bung installed.
Fuel lines need to be connected (missing some fittings).
I will be using a fuel catch tank for the high pressure fuel pump which needs to be installed.
Air filter needs to be ordered.
Need to connect the crank case ventilation to something.

So not that far off a test start

/Carl

[aj81spider]

You mentioned plugging the booster port.

Are you deleting the vacuum assist on the brakes?

[grrrdot]

Hi,
Great looking build!
330cc injectors are pretty big for a 1608, you should have a lot of room for HP from future upgrades
Looks like your using the the GM style MAP sensor. Are you running a TPS as well? If so which TPS did you end up going with?

-G

[stpher]

Just curious what you are doing with your old carbs?

Thanks, Rick

[rug]

Are you deleting the vacuum assist on the brakes?

No. I am taking vacuum from every runner on the jenveys. These are run to the vacuum log which i visible in one of the pictures above. From there I will take vacuum for the brake booster, MAP sensor, and fuel pressure regulator. I will take a picture of it for the next update.

Are you running a TPS as well? If so which TPS did you end up going with?

Yes, there is a TPS as well! I'm using this one from jenvey:
https://store.jenvey.co.uk/throttle-bod ... n-cp17-tp1

When I get everything up and running we will see if I can run fueling on speed density with MAP-reading or if I will need ITB mode which combines MAP at low loads and TPS at high loads.

Just curious what you are doing with your old carbs?

I am keeping them for now. I am so far only doing reversible mods for the unlikely reason I sell the car and the next owner wants to convert back to pure carbs

/C

[engineerted]

WTF!!! why can't i see the images?????

[rug]

WTF!!! why can't i see the images?????

They are posted as img-links. Maybe you can't reach the domain where the images are stored? Here is one:

http://www.familjenwahlin.se/vacuum-log-MAP.jpg

/C

[rug]

The Microsquirt is up and running

I got good readings from all sensors and I got RPM input from my coil. Injectors are fireing as well so almost done for a test start!

I am waiting for a high pressure pump but it will probably not arrive until next week. I was also planning to put an O2-sensor in the stock exhaust but I tried getting the downpipe out of the car but the pipes are rusted together solid... Thinking I might replace the whole exhaust but it is an expense I wasn't planning for until later.

/C