Your premise makes sense, except the cooling doesn't necessarily all happen immediately at the point fuel is introduced. With port EFI more of the fuel vaporization happens after the air is in the cylinder which is too late to improve flow.
Dyno Testing Bolt-ons On The 4.0
- Thread starter Jezza
- Start date
Your premise makes sense, except the cooling doesn't necessarily all happen immediately at the point fuel is introduced. With port EFI more of the fuel vaporization happens after the air is in the cylinder which is too late to improve flow.
I heard about the same cam core supply issue more than a year ago. I don't think it's going to be solved anytime soon
It's funny how that happens. I guess we should take it PM and stop muddying this thread if you want to keep talking. Maybe you can explain the mechanics of carb & TBI throttle blade icing.I assume it has something to do with a pressure drop. Maybe that also cools the charge, but I'm wondering away from the thread again.
yeah, it's a combination of pressure drop in the air and cooling from the evaporating fuel. Never personally experienced it on my carb'd vehicles, but from what I've read about it in aviation it sounds like it's more about the air pressure drop because it seems to happen more frequently on extended, closed-to-part throttle periods such as during descent - which would be a time of more air pressure drop and less fuel supplied.
yeah, it's all based on being fully vaporized before crossing the "finish line", which I have been thinking of as when the valve closes. That's where I started with my first post in this thread about whether the different injectors make a difference in how completely it evaporates before the valve closes.
I'd gladly give up 5hp to be rid of carburetors every single time. Engine life,fuel economy and maintenance are far too important to me.
The only examples I want a carb on are Briggs and stratton,honda,stihl,husky,etc
The only examples I want a carb on are Briggs and stratton,honda,stihl,husky,etc
I dunno, man. My lawn mower is fuel injected. Not having to worry about the choke, float levels, jets getting plugged up, etc is pretty nice.
I'd be happy to ditch carbs on everything. I've already gone Milwaukee M18 for all the stuff that used to be 2 stroke. All I've got left is the push mower and the lawn tractor.
Re: the injector quandary
https://wranglertjforum.com/threads/single-4-port-12-port-injectors-on-a-dyno-with-a-xj.74163/
The video linked in the above thread demonstrated small gains (on the order of 4hp) for the increased hole count. One issue though...at the end he posted the chart that included the AFRs for all runs and they were not the same. Question for the tuners in this thread- when the PCM goes open loop at WOT, is there any long term fuel trim in play? I know there are different LTFTs saved in different parts of the map but I don't know if WOT even calculates any, or if they're copied or extrapolated from smaller throttle openings, and if they are, do they get used for WOT...
What I'm getting at is whether there's utility in getting a few drive cycles in for the LTFTs to adjust before putting it back on the rollers.
https://wranglertjforum.com/threads/single-4-port-12-port-injectors-on-a-dyno-with-a-xj.74163/
The video linked in the above thread demonstrated small gains (on the order of 4hp) for the increased hole count. One issue though...at the end he posted the chart that included the AFRs for all runs and they were not the same. Question for the tuners in this thread- when the PCM goes open loop at WOT, is there any long term fuel trim in play? I know there are different LTFTs saved in different parts of the map but I don't know if WOT even calculates any, or if they're copied or extrapolated from smaller throttle openings, and if they are, do they get used for WOT...
What I'm getting at is whether there's utility in getting a few drive cycles in for the LTFTs to adjust before putting it back on the rollers.
lol, that wasn’t part of the equation! It’s a John Deere quik trac 652. 52” deck and 26hp kohler. Zero Turn stander. It’s Tim Allen style overkill for my lawn, but it only takes me about 20 minutes a pop to mow (which happens about 2x a week this time of year)
We may not have a choice much longer. I walked through the mower aisle at Lowe's a few weeks ago and 3/4 of them were electric.
I'm not opposed to the idea but I need a good 90-120 minutes of run time out of my push mower and need my lawn tractor to give me basically an entire day depending on what I'm doing.
I'm not opposed to the idea but I need a good 90-120 minutes of run time out of my push mower and need my lawn tractor to give me basically an entire day depending on what I'm doing.
Neighbor has two of them. Things are annoying to listen too and don't really do a great job.
oh that's a good one.
The great thing about this data is not only does it tell us how much power it costs, but probably more useful is how much extra fuel it burns, and how much extra heat the cooling system has to reject to make that power.
I'm going to go ahead and say that's well out of testing for Jezza. I think the best "test" for those would be real world, long term fuel/mileage logging.
You're right. I wasn't thinking about the path of power flow for that.
You'd have to have the rig on a treadmill, or on a 4 wheel dyno where the front rollers were driven by the rear rollers.
Yep, a full 4 wheel/AWD dyno or 4 hub dynos, neither of which are very common.
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