x450-x-1 starting probs/rich idle/no power over 4,000rpm

[Steptoe]

The afr at idle is pretty constant from 14.6-15.1, On the pedal between gears it goes to the 13s and back to 15s but decelerating its above 17

yep those are pretty good.. I would try to get a few more pionts into the idle the 17 as mentioned above somewhere is ok so long as when u come off deceleration the response in the AFR to 'normal' is virtually instantaneous

As to non std hose clips on ANY LPG line other than converter to mixer....BIG non no be it temp or otherwise....and highly illegal anywhere.... and 'accident' waiting to happen... big 'accident'
'accident' bottom line equals purpose built man made disaster.

have u made supports to take the weight of the converter off the joint into the mixer... these are soft ally materials certainly not designed to support any weight/ vibration / stress etc

[flatblack]

There is a bracket on the back using one bolt hole of the e, it supports it from just hanging there. I picked up 2 3/8 flare to 1/4 pipe thread adapters and 2 90 degree field fittings. The hose will be about 16 inches long with only 2 pipe to flare fittings. Im going to stop at tractor supply after work and pick up a conduit clamp for the lockoff and filter. If I lean the idle out more im afraid it will be harder to start cold, ill lean it out more tho and see what happens.

[flatblack]

I adjusted the idle afr and now its in the mid 15-16 range at 850 rpm, when I stand on it the afr was in the 13-14s but decel was in the high 17s. I adjusted the metering rods a little shorter too and that brought decel a little richer in the 16s. Under load is now in the high 12s, im going to see if any thing differs when I swap the fittings to line. If the afr's are all good ill then go onto mapping the timing and see what I can do with it for the time being.

[flatblack]

I changed the fittings and ran a new piece hose, worked out real nice with the rubber coated clamps. Started up pretty easy but was real rich, low 12 afr. Idled real rough that way. I adjusted idle so I have mid 15s to 16. It started up real nice this way and seemed to rev up much nicer with the afr leaned some. What I don't get was with just changing the fittings to line why such rich afr #'s, could there of been that much restriction with all those joints and elbows..?...Now lockoff is straight thru also and no elbow.

[C3H8]

Very strange. Liquid is supplied all the way to the reg no matter the connections. Even if any restriction was evident it would normally only affect the higher load situations, plus you would normally see frost on the fitting(s) if there was a restriction. I really would not expect the AFR to be affected at idle just by changing the fittings. Your description of the current set up would indicate a much more efficient system which should be trouble free.

[flatblack]

I didn't think changing the lines would effect anything, so why the difference im not sure. Im going to go thru all the conections with soapy water to make sure everything is good. The fittings weren't easy threading on either. Ill see how if fires up today, if the afrs stay higher at idle like I set them yesterday. The way it was before with the long vapor hose the idle had to be high 14s-15 to start easy. Hopefully the way its setup now with everything all being new will be a trouble free setup.

[flatblack]

Just changed all the vacuum hoses and put new clamps on everything, started right up and idled super nice with a afr of 15.3-16.2. Throttle response is better than it ever was, it revs pretty nice to over 5,000. Under wot its in the 12s afr and only 15 deceleration. Would 13s on wot be better..? Idles back nicely with temps staying in the 150-160 range. Hopefully it doesn't ping on the next few rides, if the afr #'s stay good ill mess with the timing, going to check the plugs too to see what they look like.

[flatblack]

Prob talking to myself a lot..lol...but that's ok.

I had a rich afr when on the throttle, in the 12s. I lengthened my metering rods up to .835, that made it in the 13s. Deceleration is high 14s-low 15s, seems to rev up clear and crisp. Still seems to build power up to about 54-5500 and then no more. Temps still stay perfectly in the 160 range and the plugs are really clean looking. The timing right now is 14 degrees initial and 34 degrees at 3500. Still seems to run decent and build good power, it starts up easier too. When cold if I crank it over a few times then let it sit and just crack the throttle then hit the key it turns over 3-4 times and is running. When cold its just a tap of the key. Since I changed all the vac hoses, new msd plug wires and re gasketed my collecters on the headers my afr is more constant and not all over idiling. So far so good, im going to drive it later on a 20 mile trip thru the mountains here and see how it does pulling the hills.

[Steptoe]

Prob talking to myself a lot..lol...but that's ok.

No
Sry been out fishing..

idled super nice with a afr of 15.3-16.2. Throttle response is better than it ever was, it revs pretty nice to over 5,000. Under wot its in the 12s afr and only 15 deceleration. Would 13s on wot be better..?

Doesnt come much better than that....

The timing right now is 14 degrees initial and 34 degrees at 3500.

Really need a faster curve.. all in more around the 2500/ 2800
14 degrees is a marginally heavy on the starter over time... if u get to the starter doesnt turn over when the engine is warm... that will be the reason... high current draw thru the armature over time.
Are u using a afr gauge or a data logger? if a data logger connect a knock sensor up and also monitor that if worried about detonation.
On those dizzy numbers above a VA with around 6 or 7 degs in and all in around 12 or 13" will certainly help out mileage.
And if connected to manifold vaccuum and the take out the same amount out of the cent degs (lower the initial) will spin up the motor on the starter faster... with substantial faster starting

I get the impression that you are still over anylising when other than a couple minor tweaks u are all there...
Even in the state u have now would be more than acceptable and from here on in...
change the oil ever 6 months,
Check PCV valve is clean
change plugs every 3 years,
flush the raditor every 2 years...
and check the intial and total timing,... chances are u will not have to change anything till the dizzy bearing are worn out in 12 or 15 years time.
make sure the VA diaphram doesnt leak...

And spend more time with the grand children and take up fishing lol

[flatblack]

Going to run out a locked out hei soon, that's next on agenda when parked for winter....will be in a few weeks but the weather has been great here. I have a 4 hp mini starter, it starts it up pretty fast. Im using an afr wideband, Im looking into a data logger tho.

The maintenance ive lacked some but recently got all taken care of. Coolant was just flushed when I did the thermostat and ran the new coolant hoses for the model e. The ignition I did the new plugs a week ago and new 10mm plug wires today. The vacuum hoses and the pcv are new, earlier this week I changed them all. The fuel line is all new along with all the fittings from the tanks all the way up to the lockoff.

[gottago]

Good to see the progress fb. Likewise say you are getting pretty close and just need some fine tuning from there. I think stept is giving advice on the distributor that may be helpful to try. You had room to go on the timing according your plug readings. I think this part was a litle more for the sake of economy than what you would like though.

And if connected to manifold vaccuum and the take out the same amount out of the cent degs (lower the initial) will spin up the motor on the starter faster... with substantial faster starting

If you aren't having difficulty spinning it over, I'd keep the higher initial. If you drop the initial timing for the sake of having vacuum take over, what happens when you floor it? You have no vacuum and your initial is now too low to pull hard.

For what you want, the locked method may work best. A steeper curve than yours would help out too.

[flatblack]

I changed the plugs to a set that are 2 steps colder than I had in the pics. I ran the truck around a few good hot laps and some crusing around, pulled a plug and there still clean and unburnt with a nice clean ceramic too. I don't see a real good timing mark on them yet tho. The plug wires were msd 10mm and pretty rough, some cracking and dry looking. I put new 10mm msd spiral core race wires on, That's about 100.00 set of plug wires but have worked good and are 5 years old. I have no problems spinning it over at all, the starter is pretty healthy. Power master makes some pretty high hp starters, special for 11.5 up to 14:1. I tried to make sure everything was done right the 1st time but it hasn't come out that way. Although it has progressed pretty well...learning process, everyone here has helped a ton. I cant thankyou enough.

On this pdf below is for the distributor curve change, it shows the stock curve for my distributor also. In figure #1 the solid bar, purple and brown are what I have now. It can be adjusted from 16 degrees advance up to 32. By just a small adjustment I can mess with this a little until I change to one that's locked out. Take a look and tell me what you think. Shows the stock set advnce starting in the 1100 range, mine idles at 850. Would it be better come in at 1000 with 14 initial and have 16-20 degrees advance by 3000, I can limit to 16-20 degrees advance and be all in by 2500 and have 30-34 degrees total....this is for the time being but to also see if it makes a big difference.

http://prestoliteperformance.com/media/ ... _29014.pdf







Newest pic, new hood installed. Yes it was painted with rattle cans..lol

[gottago]

Still looks real good even for a rattle can job. Timing , hmm. The combination of all the variables comes into play for the best setup. I suspect your dcr isn't all that high given the low vacuum readings you have. Propane is very detonation resistant and likes the fast curve up to a point. The higher the compression (actual dcr) the less timing it will take. Cam dependent of course. Good idea to figure it out with what you have now. A few incremental changes will tell you a lot. Ultimately, you may find a combination that works so well with the vacuum advance even that you may want to stay with it.

I have a minor disagreement with steptoe on how much initial can be run in a performance application but real world testing speaks for itself. Every combination is a bit different. We have a small group of racers in my area who are quite into propane. Most of us started along that route by modifying our tow vehicles for power and mileage when hauling the racers around. One guy started racing a propane modified unit and lots of us have street units on propane now. Interesting how many different opinions there still are on how best to set these up. A lot of the readily available information gets you into the standard safe range for a starting point but there is room to deviate. Racer buddy has run a very fast curve that was all in at 1500 rpm. It gets very responsive the more you go that way if you have a combination that suits it. This is also where trouble comes in if you don't.

I don't have a performance chevy on the road right now but do have one on a test stand. We set them up with a basic curve using knock sensors and afr meter. Many previous have gone with a high initial and lower total with the fast curve and responded well to it. You can find many references on other sites where the performance chevy guys are running as much as 18 - 19 initial. Thats on gasoline but its not unheard of. On the ford we did a while back, timed test runs proved it did best with 17.5 initial and the total set at around 32. All in by 2500 rpm. Had to do some sligh modifications on the dizzy to get there but it has a couple of thousand miles on it now, pulls hard to 6500 rpm and the plugs have a good timing line and detonation is no problem whatsoever. Impressive for a big block. That one now runs ported vacuum to the dizzy for ease of startup and so the initial can stay high and the curve kick in fast. Its been double and triple checked with the knock sensor and tuned with an afr data logger. I thought there was an issue awhile back especially after all the warnings about too much timing but all that had happened was a broken motor mount. It pays to be cautious and to just make small changes doing one thing at a time.

I personally don't see a problem with using the curve you suggest. Start low and work up a bit while doing some timed pulls for testing... We have seen a markable difference between 14 initial and 16 plus on some performance applications. Have also seen a few chevies that pinged much over 14 initial. Plug off vacuum advance for testing.
16 good starting point for a test imo, its enough to see if it helps or hinders without being real dangerous. May have to adjust afr a touch.

I can limit to 16-20 degrees advance and be all in by 2500 and have 30-34 degrees total...

[Steptoe]

If you aren't having difficulty spinning it over, I'd keep the higher initial. If you drop the initial timing for the sake of having vacuum take over, what happens when you floor it? You have no vacuum and your initial is now too low to pull hard.

yes with the current curve thats all in 34 deg @3500.. which is one reason why LPG needs a fast, light spring curve all in mid 2000s....
with such a curve starting at the lower aprox 8 deg 1500 rpms has around 15 to 18 deg advance....which will be a little more than the current curve

[flatblack]

My distributor is a mechanical advance unit, Mallory unilite with external msd coil. Are you saying with what I have. Im better taking the initial down for a better curve..?....I was looking at those charts trying to see what the best curve is for the time being but wasn't sure.


As for the high initial when I tried before anything over 12 it would ping under heavy load. Id have to pedal my way thru it.