Jenvy ITBs on a Ford Kent 1700 Xflow

[GLBaxter]

All,

 

I'm thinking of replacing my troublesome Weber 40 DCOEs with ITBs, specifically the Jenvy variety.  I like the idea of fuel injection and tunability, but looking for specific advice / information is lacking.  Has anyone done this and in general, is this something that can be done by a fairly technical, retired engineer feasible?  I would really appreciate some feedback on this.  Also, the car is located in N Va, so are there any good wrenchers that can be recommended?

[fastg]

Interesting project. Very possible,   I think a MegaSquirt would be a good place to start your research. Your going to need a crank and probably  cam position information. Solve those problems and you will be well on your way.

 

Graham

[MV8]

Jenvey is only one supplier of DCOE flanged  ITBs but they are much more expensive.

 

It is less work to tune your carbs than to convert and tune (using carb tuning skills with the key board). This guy had a base map from a fellow enthusiast to get a big head start. 911 but essentially the same process:

https://pcaucr.org/2019/12/diy-webers-to-efi-conversion/

[JohnCh]

I pondered this many years ago but ended up doing a Duratec swap when I rebuilt the car.  After speaking with some knowledgeable crossflow tuners in the UK, the consensus was it's a lot of effort and expense for not much return unless the objective is to build a very high horsepower engine (alloy head, bigger valves, very hot cam, high compression forged pistons, etc).  I was told the best upgrade was to move to a 3D timing setup which would make big improvements to drivability, mpg, and make a cam hotter than the Kent 234 not an issue for a street car.  Of course, sometimes doing things like this are more for the challenge than the ROI.  

 

I believe kits are still available from the UK to do the conversion which will be worth investigating, if for no other reason than to understand all the parts required on the engine side. You will also need to convert the chassis.  This I have done.  It's not hard but there are a number of things to do.  Big ticket items are converting the fuel plumbing to account for the high pressure, a return line, fuel filter, and a surge tank or modified fuel tank, and making changes to the electrical system to support the ECU, fuel pump, and various sensors on the engine.  As for the ECU, I recommend going with something where they will either supply a crossflow starter map or you can get your hands on one from someone running that same setup.  This will make things much faster and easier.

 

Regarding your Webers, what troubles are you trying to overcome?  Are these things that can be more easily addressed with a rebuild or jet changes? 

[MV8]

I'm also curious about the issues you having with the webers. I don't know any mechs in your area.

 

Could also switch to a simpler induction with a single dcoe or downdraft intake and carb (with the lotus scoop for air cleaner clearance). Another option is an oem style plenum intake made to fit the kent with injector bosses for a fuel rail and a standard throttle body at the rear instead of four throttle bodies.

[GLBaxter]

5 hours ago, MV8 said:

Jenvey is only one supplier of DCOE flanged  ITBs but they are much more expensive.

 

It is less work to tune your carbs than to convert and tune (using carb tuning skills with the key board). This guy had a base map from a fellow enthusiast to get a big head start. 911 but essentially the same process:

https://pcaucr.org/2019/12/diy-webers-to-efi-conversion/

MV8, thanks for the link.  I've spent a considerable amount of time on my laptop looking at various videos and textual feedback episodes on doing the conversion and I will check out your link.  Yes, it is a bit of a PITA (pain in the ass), but I like the idea of doing the changeover myself.  True, the gains may be minimal, but it's my understanding that Weber's are not a set and forget option.  I guess I'm just silly that way.

[GLBaxter]

5 hours ago, JohnCh said:

I pondered this many years ago but ended up doing a Duratec swap when I rebuilt the car.  After speaking with some knowledgeable crossflow tuners in the UK, the consensus was it's a lot of effort and expense for not much return unless the objective is to build a very high horsepower engine (alloy head, bigger valves, very hot cam, high compression forged pistons, etc).  I was told the best upgrade was to move to a 3D timing setup which would make big improvements to drivability, mpg, and make a cam hotter than the Kent 234 not an issue for a street car.  Of course, sometimes doing things like this are more for the challenge than the ROI.  

 

I believe kits are still available from the UK to do the conversion which will be worth investigating, if for no other reason than to understand all the parts required on the engine side. You will also need to convert the chassis.  This I have done.  It's not hard but there are a number of things to do.  Big ticket items are converting the fuel plumbing to account for the high pressure, a return line, fuel filter, and a surge tank or modified fuel tank, and making changes to the electrical system to support the ECU, fuel pump, and various sensors on the engine.  As for the ECU, I recommend going with something where they will either supply a crossflow starter map or you can get your hands on one from someone running that same setup.  This will make things much faster and easier.

 

Regarding your Webers, what troubles are you trying to overcome?  Are these things that can be more easily addressed with a rebuild or jet changes? 

Hi John.  I've read and re-read your experiences on Throttle Steer w.r.t your Westy et al, especially the Rebirth, Specs and Upgrade sections.  A couple of questions that we can discuss here or on a PM, your call.  I'd prefer a PM as I can be loquacious, and I don't want to bog this thread down too much.

Regards,

Greg

[JohnCh]

@GLBaxter, PM is fine.

[GLBaxter]

1 hour ago, JohnCh said:

@GLBaxter, PM is fine.

John, I went to throttle Steer / home / Email the Web Czar, and nada.  Clicking on it did nothing. Selecting Open link in a new tab did open a tab, but again, nothing.  I did like the reference to Murphy's Irish Cream Stout though.  Good stuff.

[JohnCh]

Looks like that Weebly functionality is no longer working, which explains the lack of unsolicited stock tips over the past year.  PM me here and I'll provide a working email address.

[NSXguy]

Efi conversion on a Kent / Crossflow is project, among others that has been on the docket for me but just haven’t had the time allocation to bang it out. It’s a really nice upgrade if you’re not a purist and appreciate better driveability/road manners and “reliability”(I would probably call it increased vehicle up time).

i’m Currently doing a dry sump conversion on my xflow. If I get it completed early enough, I will likely do the conversion- don’t want to risk car not being ready for the driving/track season.

I would say If you’re fairly technical, then it’s pretty straight forward and doable from the hardware standpoint; the tuning bit has a learning curve if you’ve never done. If you’ll have someone else tune then get that squared away before you commit to the conversion and make sure said tuner is comfortable with the software you will be using- sometimes the hardware suppliers like Jenvey may offer an all in one solution that includes remote tuning after hardware install. It’s better than nothing but may leave some performance and driveability improvements on the table. I was pretty much going to source my own bits but if you buy a kit, then that simplifies the process.

 

anyway, some high level points to consider:

fueling:

in essesnce,  the fuel system will need to be upgraded from a low pressure to a high pressure one. Few ways to accomplish. Lift pump, surge tank, high pressure pump to rail is one way. Some just use one high pressure pump after tank, but might be prone to surge depending on driving situation. Install Inline filter as well.  Then decide if you want return or return less. 

Trigger:

you’ll need to mount a new trigger wheel(36-1, 60-2 etc) and crank sensor(webcon makes a kit) for precise timing control. If you want sequential spark you’ll need a cam sensor installed for signal( a bit more involved, not totally necessary; something I’ll likely do on mine)
 

Ignition:

you can keep your ignition system with dizzy if you’d like (based on your tuning and trigger choices). I’m assuming you’re already on electronic ignition at least.

you can also decide to go wasted spark ignition using which is between dizzy and fuel sequential spark. Will need two coils for this, deleting the dizzy. 
 

Air:

the throttle bodies will come with everything you meed. Sometimes you may need to purchase the tps sensor. (I suspect the Jenvey has all this covered). 
 

exhaust:

you can keep your existing exhaust. I recommend you add a bung after the collectors for a wideband o2 sensor and tie it into the ecu to closely monitor afrs and for close loop corrections. 
 

Management:

any competent ecu of your choice.

 

wiring:

Can start fresh here Or add circuitsto existing harness. New looms for fuel pump(s), crank sensor, tps, injectors, cam sensor and coil(s) if sequential etc. 
 

then tune, tune, tune! 

 

[IamScotticus]

I would do motorcycle carbs.

https://danstengineering.co.uk/Ford-Crossflow-37mm-Bike-Carburettor-Starter-Kit

 

[GLBaxter]

3 hours ago, NSXguy said:

Efi conversion on a Kent / Crossflow is project, among others that has been on the docket for me but just haven’t had the time allocation to bang it out. It’s a really nice upgrade if you’re not a purist and appreciate better driveability/road manners and “reliability”(I would probably call it increased vehicle up time).

i’m Currently doing a dry sump conversion on my xflow. If I get it completed early enough, I will likely do the conversion- don’t want to risk car not being ready for the driving/track season.

I would say If you’re fairly technical, then it’s pretty straight forward and doable from the hardware standpoint; the tuning bit has a learning curve if you’ve never done. If you’ll have someone else tune then get that squared away before you commit to the conversion and make sure said tuner is comfortable with the software you will be using- sometimes the hardware suppliers like Jenvey may offer an all in one solution that includes remote tuning after hardware install. It’s better than nothing but may leave some performance and driveability improvements on the table. I was pretty much going to source my own bits but if you buy a kit, then that simplifies the process.

 

anyway, some high level points to consider:

fueling:

in essesnce,  the fuel system will need to be upgraded from a low pressure to a high pressure one. Few ways to accomplish. Lift pump, surge tank, high pressure pump to rail is one way. Some just use one high pressure pump after tank, but might be prone to surge depending on driving situation. Install Inline filter as well.  Then decide if you want return or return less. 

Trigger:

you’ll need to mount a new trigger wheel(36-1, 60-2 etc) and crank sensor(webcon makes a kit) for precise timing control. If you want sequential spark you’ll need a cam sensor installed for signal( a bit more involved, not totally necessary; something I’ll likely do on mine)
 

Ignition:

you can keep your ignition system with dizzy if you’d like (based on your tuning and trigger choices). I’m assuming you’re already on electronic ignition at least.

you can also decide to go wasted spark ignition using which is between dizzy and fuel sequential spark. Will need two coils for this, deleting the dizzy. 
 

Air:

the throttle bodies will come with everything you meed. Sometimes you may need to purchase the tps sensor. (I suspect the Jenvey has all this covered). 
 

exhaust:

you can keep your existing exhaust. I recommend you add a bung after the collectors for a wideband o2 sensor and tie it into the ecu to closely monitor afrs and for close loop corrections. 
 

Management:

any competent ecu of your choice.

 

wiring:

Can start fresh here Or add circuitsto existing harness. New looms for fuel pump(s), crank sensor, tps, injectors, cam sensor and coil(s) if sequential etc. 
 

then tune, tune, tune! 

 

Seriously, you have/had a fine stable of cars.  I've got a Porsche Boxster S, Special Edition that my wife drives and a few interesting mounts in the past.  Driving the Boxster and the Westfield back to back are completely different, no comparison (except the obvious ones). 

 

I've decided I'm going to hammer on the Webers until I get them working acceptably well, then order up the ITBs and take my time.  I've read some horror stories about noobs installing the ITBs and not knowing exactly what to do.  Now, again; I'm not a complete idiot, I mean other than owning a Type 7, but when I did get to drive it, it was a blast, so better to enjoy even the carbs, then upgrade to ITBs.  Your comments are spot on and greatly appreciated.

[GLBaxter]

52 minutes ago, IamScotticus said:

I would do motorcycle carbs.

https://danstengineering.co.uk/Ford-Crossflow-37mm-Bike-Carburettor-Starter-Kit

 

Now THIS looks very interesting.  Thanks, I have some web schlepping to do now.

[fastg]

Nice setup, but you will still have a tuning issue. Good luck finding a dyno operator that will tune them. But if you want to stay with carbs they are far better then Weber's

 

Graham

[GLBaxter]

All,

 

Thanks for all the feedback.  I've decided to go with a Nodiz 3D ECU which seems relatively easy to install, then a bike carb setup.  I'm still going to bang on the Webers, but I've seen many references to them going out of tune rather frequently and needing screwing around (literally) which frankly just annoys me.  The bike carb and upgrades ECU seems to be the proper setup for updating my somewhat upgraded Ford Xflow engine.  I'm not really looking for massive HP/TQ boost with this engine, just better drivability.  I'm saving that for a future upgrade with a (probable) Duretec and some goodies on top of that.  Near term, I just want to spend some time driving around my stomping grounds here and enjoying the car with my wife.  Yeah, I'm losing some performance, but saving appx $3K in cost, so a good swap IMHO. n Any further thoughts will be greatly appreciated.

 

Kudos to JohnCh and IamScotticus for their suggestions. 

 

Greg

 

P.S., Driving 4 Answers did an extensive series of vlogs on upgrading his Mr2 Toyota w/ bike carbs.  Worth checking out.

[wdb]

I have to admit to having a tear in my eye as I read about the terrible Weber carburetors. Ever since I was a teenager I craved having one (Mini Cooper) or two (MGB with crossflow head) hanging off the side of the engine under the hood of my car. Yes they're fiddly. But when they're on -- as I have the great good fortune to experience in my Caterham (thanks Al!) -- they are just sublime. And they look like nothing else ever has or ever will in an engine compartment. I now find myself with three pairs of them and I intend to keep them all. My Weber education awaits!

 

That having been said, and I might be a bit daft saying this, but I've always found SU carbs to be the simplest way to feed fuel, and about as hard to set up as falling out of bed. Get the right needle in there, fiddle with linkage balance if you have more than one, and off you go. Keep the dampers topped up every couple of weeks. If I ever find myself fed up with Webers, I will look into replacing them with SU's.

[IamScotticus]

A side note, the link I posted to those bike carbs isn't the only bike option out there, it's just the first one I found.  Shop around.  

The other option I would suggest is the old downdraught 32/36 or 32 DFV.  This would be a loss of performance and a hole in the bonnet, or a new bonnet so you don't have to ruin your present one.  Getting the engine to run on a single carb should be easy, it's all the other bits to accommodate it that are the pain.  It's a fringe choice, but the end result should be a solid and drivable carb.  A very enjoyable car.

[speedwagon]

The major advantage of the SUs is that they tend to mix air and fuel by weight allowing a sea level tune to function  well at 14000 feet. This makes the simpler alternative to FI. They can also be sealed and used on "blow thru" applications harder to synchronise but that is not that hard to learn. my carbs of choice john  PS the bowl and float make them ideal for hard cornering and off road use.