Road going ITB setup

[AustrianVespaGuy]

On 4/12/2020 at 2:20 PM, Harv said:

ported head, schrik 304, wasted spark, S14 crank, forged pistons, 2230cc. Tuning the 45’s is difficult for the throttle tip in.  70% of throttle is in the first 30%. 

This is 100% correct, and it's also to important to remember that a 40mm throttle BODY is the full 40mm diameter all the way through, where as a 40mm diameter CARB will be choked down to something more like a 34mm diameter at the venturi, so in terms of airflow you can't really compare carb throttle plate sizes to TB throttle plate sizes.

[AustrianVespaGuy]

1 hour ago, pato2002 said:

Now, I want AC but cant really come up with a method I like of shoe-horning it in with the turbo

So, while I get pretty severe sticker shock from it, I'm delighted that someone has FINALLY made a good looking electric AC kit for 911s. . . maybe one day we'll be able to figure out something similar (and hopefully without the requisite 911-markup!) for 2002s!

https://www.classicretrofit.com/collections/electric-air-conditioning/products/air-conditioning-kit-for-classic-911-full-kit

(Sorry for the topic drift, back to ITBs now!)

[Dudeland]

17 hours ago, pato2002 said:

I hope to see you there and we can discuss this more over beers. Cheers.

I have been dreaming of getting there for the last 4 years.  I am in Canada, with only one shot of Zenica, so the chances of getting there this year are slim to none.  I will take you up on that beer. 

 

Regarding the A/C I am going to try to shoe horn in the turbo with my A/C.  I think I may be able to get it fit, but the challenge is not to cook the compressor and leave enough space to service it without dismantling it. 

 

Kind Regards

[squirt46]

It's been dang near 3 years since I first posted regards our efforts to install a 'stealth' EFI conversion on our orange 73 2002, and we're finally making some forward movement.  These photos show the remote oil filter mounted to the starboard side front frame rail; the hoses running along just below the radiator, and the fuel pressure manifold that will be hidden below the battery box and dummy battery.  Brackets were all installed with nutserts; the oil filter mount was a local speed shop purchase; hoses are Evil Energy as are the hose separator clamps.  Oil filter mount cut from aluminum channel; the 'L- shaped brackets for securing the hoses are also cut form aluminum and located such that they'll fit into the 'dints' in the bottom of the radiator.   They are mounted to the chassis nutserts with countersunk allen headed bolts, so as to clear the rad.

[squirt46]

We had (small) hopes of maybe starting her up a week ago (Dec. 23) but didn't get that far.  Cranked the engine over the for the first time in human memory and the oil pressure light went out, so that was a good sign (no fuel in the tank; we're also holding off on reassembling the rad/fan/cooling system until we did get her running so as to have maximum access to the fuel/oil/efi etc. systems).  There didn't seem to be any oil in the remote mounted filter (which is confusing:  pressure seems to be okay; why no oil?).  Jeff added oil to the vertically mounted filter and - voila! - we apparently have oil through the lines, based on the puddle on the floor under the adaptor plate to the block.  Tightened up the fittings and figured we had that resolved.  Pulled cylinder 4's spark plug lead, popped a spare plug into it and cranked:  not quite a voila! moment as we got one fat spark on the first crank, and then no more.  Checked 3 and 1, and no spark at all.  So that's today's task:  chasing the coil packs.  I gotta take a run and pick up some more gasoline (weather was above freezing t'other day and I used the jug for the 02 and topped off my old Buell motorcycle, and forgot to refill) and we'll put some in the tank so the pump isn't running dry for future cranking.  The heat shield over the stainless header makes playing with the spark plugs a bit of a pain.

[squirt46]

Jan. 27/23:  added gas to the tank this afternoon (yay!  first time since Noah was looking around for gopher wood) and - not a whole lot.  We have fuel pressure, but no spark.  It appears that our trigger wheel sensor has the wrong spacing.  Dang!.  Digressed onto fixing a wiring issue for the right front (starboard?) signal light.  wires were messed up. but resolved.  I wasin the house earlier when Jeff came in and advised that a fuel pump works better when the 'suck' and the 'blow' lines are properly connected. 

But!  We've got fuel to the manifod (and, presumably, to the injectors), but we're not getting a spark.  Touch wood, next week!

[squirt46]

March 17/23:  Yay!  It started!!!  Jeff's been beating his head against the wall, looking for reasons why we would get a single spark and then nothing (we did manage a backfire a few weeks ago, proving that gasoline was getting to the combustion chamber.  One of the two chaps who makes up Simple Digital Systems (we're using their ECU, injectors, fuel manifold, pressure regulator etc. etc. etc.) was good enough to come by this afternoon and an hour or so later, found that the chap I'd bought the unit from (used) had switched wires in one of the input cables (SDS did upgrade the unit to modern specs a few years back).  Small flame out of the tail pipe and it started immediately and idled, but we're getting gasoline puddling in the carb bores (we're using gutted Weber DCOEs as throttle bodies and have the injectors mounted on the underside, at 45 degree angles, aiming towards the butterflies, with the injector about 2 inches upstream from the butterfly).  The fuel pressure is too high at the manifold and we've (ie. Jeff) got to do a permanent fix on the wiring.  Figure we'll disconnect the return line from the regulator and drain it into a jug,  crank it over and watch the pressure.  Get that issue fixed (messed up return line somehow (it's a new installation by Jeff_)? faulty pressure regulator?), and then start it again, with fingers crossed.

I think I adopted the idea of injecting upstream of the butterflies based on early domestic fuel injection systems and the conversion kits that Patton Machine has developed for SU and Zenith-Stromberg carbs as their injectors are also upstream of the butterflies.

The car started almost instantly, and the fact that it started makes this A Very Good Day!.  If anyone has suggestions as to our puddling problem, please advise.  Thanks, 

[jimk]

It appears to me that you will have to live with the puddling because the injectors are spraying onto cold metal parts.  The fine spray is forming larger droplets on those surfaces, the big droplets won't stay suspended in the air stream at low air flow rates.  Visualize rain hitting the windshield and draining away in large streams.

 

The early systems that sprayed above the throttles were downdraft designs operating at 10 psig fuel pressure.  As described in the GM manuals, the throttle at idle needed to be a less than 3% to assist in breakup of the fuel drops passing beyond the throttle. 

[Dudeland]

I also get a small amount of puddling with my TBI sniper system,  largely due to the hard left-hand turn it takes in the manifold.  At idle, my 2L doesn't shift enough air for the size of TB (about 51mm X2) I have.   Once I am off idle, it clears its throat and dries out quickly.  Just before I put it away for the winter (2 years ago), I took a lot of fuel out of the idle, and it fundamentally solved it. 

[squirt46]

Thanks guys!  Figure:

1 - pull an injector and figure out what the rating is, to ensure that they are reasonably sized

2- get the fuel pressure adjusted properly (plugged return line?  faulty pressure regulator?)

3 - try looking down the DCOE throat, and maybe learn something regards when puddling starts, and if it goes away at higher rpms

4 - slip a venturi into the DCOE throat and temporarily secure it upstream of the injector, and see if the increase in air flow velocity makes a difference

5- are the DCOE throats level, or maybe tilting down towards the air cleaners?  Lower the passenger side of the car, with the idea being to make the excess fuel flow towards the intakes, such that the sensors will see an increase in fuel in the combustion chamber and dial back on the amount being injected (I know less than nothing about EFI, and am assuming a bunch of stuff here)

6 - just get the vehicle running and insured, and get it out on the road with it operating under load and see how it behaves

7 - throw more money at the system

Thanks for the thoughts guys!

[tzei]

Pos. 1 & 2 - YES!!! All is futile until these are sorted.

then pos. 6 and eventually pos. 7

[squirt46]

Oh, Lord!  a 'gofundme' is next on the list!

Seriously:  will report in as we learn more.  Thanks all.

 

[jimk]

This is not a no return fuel system.  If the return from the regulator is blocked, the fuel pressure will go very high and the pump may become noisy.

[squirt46]

Looks like one problem is that the injectors are rated to move 31 lb/hr at 43 psi; found my old calculations plus did two more from two different on-lines sources, and they say I need 22 lb/hr.  Dunno how I screwed up and apparently bought four of the wrong injectors.  Will try to figure out the fuel pressure issue and get it corrected, then start the engine and see how that goes.  Then (probably) new, smaller, injectors.  The journey continues!  Optimistically!

[NickVyse]

17 hours ago, jimk said:

This is not a no return fuel system.  If the return from the regulator is blocked, the fuel pressure will go very high and the pump may become noisy.

 

A Hardi pump would solve that - it only pumps when required and maintains a steady pressure.

 

Kraftstoffpumpe 18812 (12V / ab 100PS) - HARDI Automotive

WWW.HARDI-AUTOMOTIVE.COM

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HARDI Kraftstoffpumpe 18812 für den größeren Druckbereich 0,28-0,35 bar. Förderleistung 100-130 Liter/h. Betriebsspannung 12 Volt.