NOHOME
PowerDork
3/20/17 7:31 a.m.
I recall reading somewhere that the factory "bolt it on and drive" setting is always a bit rich so as to be safe for a large spread of engines. You adjusted the idle screws, but the mains could bear some investigation maybe?
You are living the reason why am plan to go Fitech with my 302.
GPz11
Reader
3/20/17 7:35 a.m.
You still have to tune FItech just like a carb but you use a computer and he uses a screwdriver.
Some of those systems say self tuning but they still need some tweaking.
NOHOME
PowerDork
3/20/17 8:37 a.m.
GPz11 wrote:
You still have to tune FItech just like a carb but you use a computer and he uses a screwdriver.
Some of those systems say self tuning but they still need some tweaking.
Not sure what you mean? The whole reason for the Fitech and the Holley Sniper to exist is to do away with the need to tune the running mixture. Not like megasquirt of some of the early EFI systems where you need to drive around with a laptop and crate fuel maps.
I have played with carbs long enough to know that very few are ever tuned right for the entire operating range of the engine. Carbs dont have a feedback loop that tells you the setting is optimal, so it is a "best guess" at best, unless you have a dyno.
GPz11
Reader
3/20/17 9:00 a.m.
A buddy installed a FItech system on his vintage Mustang and it wouldn't run correctly until he went in and do some tuning. Something to do with the accelerator pump function. It would go pig rich until he tweaked it.
He tried to let it auto tune for it but it wouldn't correct it for some reason.
Maybe his was a isolated issue but you still might have to tweak it.
pres589
PowerDork
3/20/17 9:08 a.m.
Total derail on my part, don't mind me or nothing; the FiTech doesn't seem to use a computer at all, just some basic information handed to it by a handheld display/controller/logging box. Witness; http://www.hotrod.com/articles/1968-plymouth-valiant-fitech-reinvents-efi-how-they-do-it-better-and-cheaper/
I wonder if there's a market for a two-barrel version for engines small enough that a four barrel doesn't make sense. Or trucks that really shouldn't get an "upgrade" to a four barrel. Probably not enough of one to make sense.
GPz11
Reader
3/20/17 9:16 a.m.
The controller is the computer
pres589
PowerDork
3/20/17 9:23 a.m.
The controller obviously has logic in it but when someone says they tuned their EFI setup with a computer, I think of a laptop running TunerStudio or something more along those lines. Not an accelerator pump function tweaked with a handheld bespoke control head. To each their own I guess.
GPz11
Reader
3/20/17 9:36 a.m.
What I was trying to say was that you might not be able to plug the FItech system in and expect it to run perfectly, ya might have to do some tweaking.
NOHOME
PowerDork
3/20/17 12:38 p.m.
pres589 wrote:
Total derail on my part, don't mind me or nothing; the FiTech doesn't seem to use a computer at all, just some basic information handed to it by a handheld display/controller/logging box. Witness; http://www.hotrod.com/articles/1968-plymouth-valiant-fitech-reinvents-efi-how-they-do-it-better-and-cheaper/
I wonder if there's a market for a two-barrel version for engines small enough that a four barrel doesn't make sense. Or trucks that really shouldn't get an "upgrade" to a four barrel. Probably not enough of one to make sense.
Based on my long experience in the Brit car community, I think that if someone put out a two barrel version of the Fitech similar to the Weber DGV, it would be very popular.
SU carbs are wonderful things if they are in good shape and you have passed the Phd level ninja class on tuning them, but that leaves a lot of less than ideally tuned Brit cars on the road.
That's all interesting guys, but I've got a carburetor here.
But the discussion did get me to perform a google search about the FItech system. That will warrant some further research for future projects.
petegossett wrote:
In reply to ClemSparks:
Have you pulled any of the plugs to see how they look, or if you can smell raw gas?
That is exactly my plan for this evening or whenever I get the chance next. A few posts up when I was reinstalling the distributor, I had a couple of spark plugs out and they were black and sooty.
I used to work around engine builders who read plugs by getting "a clean cut" at wide open throttle. The driver shut off the engine at load and speed and coasted in so the plugs gave a snapshot of what was happening under those conditions. It makes sense to me that the idle circuit should be able to tell me the same thing.
GPz11 wrote:
Also, toss a wideband on it and know exactly what it's doing.
So, how far do I stand from the car when I toss it?
Seriously, though...as I mentioned, I don't have a wideband O2 thingamajig. I'd be interested in looking into getting a setup since I have a bunch of carbureted projects in the pipeline. I'd welcome pointers/discussion on a good system or how to choose one.
GPz11
Reader
3/20/17 1:27 p.m.
I'm running a Innovate MTX-l and have also heard good things about AEM.
I'd stand pretty close to the car too when you toss it in. :>)
The 4160 series are rich at idle/ low throttle operation as a safety measure for a spread of engines and daily use were heat and low throttle load can vary largely. I never got mine perfect at idle but was always more worried about WOT. Holley tech support is actually fantastic but short of a wideband i doubt it will be perfect.
So yesterday evening I pulled the #5 spark plug (because it's SO easy to pull that one) and it looked like this:
MUCH better than my foggy memory of the same one I pulled a couple weeks back before the carburetor adjustment.
I don't remember the exact conditions when I shut it off. I am confident it was up to temperature and I'm pretty sure I just turned off the key at idle. So I do think this adjustment was a move in the right direction.
This evening I decided to see if I can diagnose some gauge problems. The oil pressure gauge works, and that's good. The second-most-important gauge, in my experience, is the water temperature gauge. It (along with ammeter and and fuel gauge) has NOT been working.
So I got out the EVTM and did some continuity checks on the water temperature gauge circuit. It checked out ok from the sender back to the last accessible connection before I had to start pulling the dash apart. So I pulled the gauge cluster to find that one of the two electrical connectors to the back of it had been left unconnected. This is the first time I've had the gauge cluster out, so that's my alibi.
I plugged it in and fired the car up to see if the gauge would work. And it does appear to be working!
I didn't let the car run long because I still wanted to pull the thermostatic fan switch to send back for warranty (Summit is sending me a new one and the defective one needs to go back). I just ran it long enough to start to see the temp gauge needle move a little.
I didn't figure out anything on the Ammeter (not super critical, really) or the Fuel gauge (I sure would like to get THAT working). I did check resistance of the fuel sender circuit. It was like 60 Ohms. I added 5 gallons of gas and got no change in resistance. I did not, however, have the key on for this so I expect that may have been a problem.
When I was done with that I decided to pull the #5 plug again to see what it looked like. Keep in mind here... I didn't get the car anywhere close to warmed up. So I expect this might be a normal (rich) result for a relatively cold condition.
My replacement fan switch came today and it didn't work either. I got out the multimeter and did some scientific testing in the kitchen. The thing just wouldn't close. Summit is sending me another. Hopefully the third time is the proverbial charm.
That did give me a chance to check the water temp gauge operation. While driving it was pretty darn low on the N O R M A L scale (that's what the gauge reads. It doesn't have number graduations...it just has a huge range with the word "NORMAL" written in it). By the time it was boiling over it was up around the A or the L. I could probably get the correct sender for the car and have the gauge read more in the center when at operating temp. I have no idea what sender is in it now. I think it's just one that was in the intake manifold when I purchased it...used.
loumash
New Reader
3/23/17 12:43 p.m.
In reply to ClemSparks:
I have found the factory temp gauges to be very unreliable and inaccurate. I still haven't gone to an aftermarket solution yet. I have underdrive pullies so that probably isn't helping matters.
In reply to loumash:
Yeah...I figured as much. I don't really need them to be accurate as long as they are indicating something fairly repeatable. If knowing the exact temperature and pressure and all that was critical, I could put in aftermarket gauges. (requiring fabrication that I'm poor at). But I don't need to know those things.
Speaking of...I've always thought I should ad a big idiot light for water temp. "Check the gauges, idiot!"
Maybe I ought to finally getting around to doing that. Gauges are great, but you have to be looking at them when something goes wrong. I usually find an overheat situation much too late in the game because the gauge doesn't draw my attention to it.
One thing that's been on my list is a PCV system for the car. A carbureted car would have a pcv in one valve cover and a hose to the air cleaner in the other valve cover. I have valve covers from a fuel injected car that has a different PCV system.
So far, I've just ignored it and been running without a PCV. But it's time to do something...even if it's wrong.
The FI valve cover has a fill tube with a hose barb sticking out the side of it as seen here:
(Yes, I zip tied a Scott towel to the plastic hose sticking out of there. But I used an actual Scott towel and two zip ties. If you're going to run temporary patches...might as well do it big.)
My thought is to get this inline PCV and put it in a hose between the fill tube and the vacuum port at the base of the front of the carburetor.
That leaves me with supplying air TO the crankcase. The other valve cover on the car has no holes, tubes, caps, grommets or other ingress as you see here:
But I have an idea, see
I have another set of FI valve covers. I can put another right side valve cover with the fill tube and hose barb fitting on the left side. I can put a breather on the hose barb or run a tube to the air cleaner. I really like the idea of running it to the air cleaner but...and this will be funny for anyone who remembers...I bought a small diameter air cleaner and there isn't enough space. The air cleaner came with a really cheesy fitting that you can screw onto the air cleaner base...but it's so bulky, and the air cleaner diameter so small that I think it would be impossible to make it work.
The only place it will physically go together it looks like it will foul in the throttle linkage. So that's a bust.
Something like this clamped onto the fill cap is probably the easy answer here:
But as I'm visualizing my PCV system I start to think..."Isn't the PCV system a substantial vacuum leak?"
I did a little googling and didn't find any definitive/authoritative discussion on the topic.
I figure I'll try it out and probably have to do a little carburetor tuning. Worst case is I ditch the PCV and go to a breather setup...but I'd prefer to run a PCV system if possible.
Curious what experience folks have with PCV and its effect on carburetor tuning.
In reply to ClemSparks:
I'm curious why you're preferring PCV to a breather? I've ditched my PCV system for breathers, but that was solely for simplification.
I guess mostly because I don't want oil residue always coming out and getting all over everything. Before I put the swanky blue shop rag over the tube in the photo it was puking oil onto the valve cover.
And it seems like a good idea for the crankcase to evacuate what gasses are in there. I assume what builds up if you don't is less than desirable for the longevity of the engine. Moisture, other corrosive stuff, etc.
All speculation.
Those are the reasons in my head...right or wrong
So I guess it's time to start thinking about an aspect of the project that I'm going to struggle with: bodywork.
The passenger door on the car is pretty rough.
It doesn't look too bad until you get a better angle of this:
I can't figure out how this damage might have happened...but it doesn't matter.
I traded two pieces of bodywork off of one of my parts cars for one "good" passenger door. This orange one:
It wasn't until after I got it home that I realized it had a shallow dent low and toward the rear. basically under the door handle at the belt line.
To quote Tommy Boy. Not so much, here or here
...but right in here:
I assume this dent should be worked out a bit before some light filler and, ultimately, paint. But I sure would take some advice. I'm guessing if I get on the backside with something pretty broad, I can probably push and/or hammer it back nearly into shape. I'm thinking something like a two-by-four used in drift punch fashion.
Has the metal stretched much with a dent this size...do I need to worry about trying to shrink it? If so, I'm all ears.
And while we're at it. What type of paint technology did these cars use? I'm relatively sure it's not a base coat/clear coat type. If I'm going to be doing some body work...I figure I'd be well served to use whatever type of paint it has on it now to avoid problems.