Efficiency potential of the L28 (MegaSquirt)

[aarc240]

1)Wrong.

2)Correct.But not without serious engineering to retro fit.ANd the benefits gained do NOT warrant the expense.

3)Last i checked,L-motors are 37+ years old.

Re 2) what serious engineering to "retro fit"? The injectors are exactly the same parts as used in a non sequential system, the difference is entirely in the ECU and wiring. Any other suggestion is leading interested people astray.

[aarc240]

Dave, what would be your expectation for the hp and mileage improvement on a N/A, stock (completely original), original compression ratio '78 engine with MS fuel control, ordinary injectors, and EDIS ignition? As I've said, my preference is to keep the old hardware, just because there's something cool about it, but if the improvements would be great enough, I could be lured to the dark side.

And Art, are you saying that I can achieve 280 hp with MSII, stock injectors, and normal aspiration, just by canning the AFM and using the larger throttle body? If so, that's darned impressive!

Umm, you might find an extra 15hp or so! Let's face it, the low compression, restrictive exhaust etc will all limit the power capability.

Realistically, an engine build is very much part of the equation.

Honestly, I'd consider MS3/MS3X worthwhile on even a stock engine but wouldn't expect much gain in power if the 280z injection is used without some mods. Economy would benefit some but nothing like it could with high compression etc (and lot's of cam doesn't help there).

Incidentally, the option to use sequential injection becomes more significant when the engine is N/A and has a lot of cam.

I ignored that, just figured the real loping idle was OK until Holden Special Vehicles Co brought out their variant of one of the LS V8's using sequential. Hmmm, decent idle yet this thing cranks out 420hp net from 5.8 litres???

Took some time getting everything else right and the L28+ still doesn't purr like a kitten but it sure is better.

Even more so on the L29+ with ITBs and stupid cam profile.

Oh yeah, Dave's last post is absolutely spot on!!

Edited July 23, 2011 by aarc240

[sblake01]

Incidentally, the option to use sequential injection becomes more significant when the engine is N/A and has a lot of cam.

I ignored that, just figured the real loping idle was OK until Holden Special Vehicles Co brought out their variant of one of the LS V8's using sequential. Hmmm, decent idle yet this thing cranks out 420hp net from 5.8 litres???

Took some time getting everything else right and the L28+ still doesn't purr like a kitten but it sure is better.

Even more so on the L29+ with ITBs and stupid cam profile.

The cams in the GM LSX V8s have very little overlap and that's why they idle as smoothly as they do (stock). I doubt if you could find a cam like that for an L series. Maybe you could have one custom ground. If you could I'm curious how that wold work with the aforementioned 37+ year old engine design. Edited July 23, 2011 by sblake01

[cygnusx1]

You guys are digging up a dead horse and beating the skeleton.

http://forums.hybridz.org/index.php/topic/68628-batch-vs-sequential-injection-for-turbo-application/

[sblake01]

It may be a 'dead horse' on Hybrid but except for a couple of sideracks (what else is new?) we're just trying to continue with Sarah's thread.

[FastWoman]

It may be a 'dead horse' on Hybrid but except for a couple of sideracks (what else is new?) we're just trying to continue with Sarah's thread.

Oh, that's alright. There seems to be a lot of beating all around. I didn't really want that.

But I think I got my questions answered. I'll study it further on my own, and when the weather gets cooler, I might decide to take on a project. Dunno.

Thanks, everyone!

[Z train]

Re 2) what serious engineering to "retro fit"? The injectors are exactly the same parts as used in a non sequential system, the difference is entirely in the ECU and wiring. Any other suggestion is leading interested people astray.

Wrong again.You need to retro fit a cam position sensor..

[Z train]

You guys are digging up a dead horse and beating the skeleton.

http://forums.hybridz.org/index.php/topic/68628-batch-vs-sequential-injection-for-turbo-application/

Gee,and the HydridZ topic almost mirrors my postings.Go figure.......

[aarc240]

sblake - that is only correct for the soft American market engines. HSV variants have significant overlap

Z train - it's actually simple enough to create a cam position sensor that one can almost do it with hand tools. Have a look at the simplicity and advantages of a 50/50 sensor in an old distributor body (which can even be lifted from a four cylinder)

Hopefully FastWoman has gained enough encouragement and seen there's so many opposing opinions that she will research deeply and go for it.

edit:

posted this on JB's forum a while back, it should help some

http://forum.jbperf.com/viewtopic.php?f=2&t=467

Since that post I've dumped the TechEdge WBO sensor interface and switched to a SLC/OEM from 14point7.

Main reason for the change was getting rid of the analogue > digital > analogue > digital chain and go to analogue > digital with the result sent over I2C to the IO/X as a data stream for forwarding to the MS3 via CAN.

Edited July 24, 2011 by aarc240

[doradox]

Wrong again.You need to retro fit a cam position sensor..

Which, with your skill set, you consider "serious engineering". Very telling.

Steve

[sblake01]

sblake - that is only correct for the soft American market engines.

Precisely why I don't have the stock cam......

(If others still wish to argue about sequential injection, etc., then I can talk about LSX engines)

Edited July 24, 2011 by sblake01

[IdahoKidd]

Seems to me everyone is overlooking the obvious. You are trying to prepay for fuel economy. You've been watching too many Prius commercials.

If gas is $4.00 a gallon: The car gets 22 mpg, that is 18 cents a mile. At 30 mpg, it is 13 cents a gallon. Driven a 1000 miles, you have saved $50. At the cost of the $1000 megasquirt system, you need to drive 20,000 miles to reach the break even point. How likely is it that you will drive your Z 20,000 miles?

If your goal is to improve fuel economy, it is a fools errand. You will spend everything you are trying to save, if not more.

My 280 gets 22-28. It is what it is. No complaints at all. My Benz gets 17. It is what it is. My 240 is STILL on the rack. It too is what it is........ : (