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Dudeland

Just strait up can't figure it out. $50 reward offered.

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After a restful time camping. And during one of my more enlightened evenings I thought about vertically mounting the tbi to a lynx manifold. It is efi so it doesn’t care about the orientation.


It would solve my fuel pooling underneath the sharp elbow. I am wondering what problems it may bring. Fuel pooling between pulses.?






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You mean horizontally mounted like a a single dcoe? It might work worth a try.

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You mean horizontally mounted like a a single dcoe? It might work worth a try.

The Linx manifold is supposed to focus the intake pulses so your two barrel carb acts more like itbs. Do I have that right?


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You need to know the firing sequence for the injectors or it could have an intake pulse of air with no fuel.

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You need to know the firing sequence for the injectors or it could have an intake pulse of air with no fuel.

It is a cis tbi type system, so no pulses timed.


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7 hours ago, Dudeland said:

After a restful time camping. And during one of my more enlightened evenings I thought about vertically mounting the tbi to a lynx manifold. It is efi so it doesn’t care about the orientation.

This would be so majorly trippin! That mind of yours.

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I don't really think fuel pooling is actually your problem, but regardless I agree the sniper should work on the Lynx.  Only trick might be clearance, especially with the normal non-tii brake booster, but my gut says it can probably fit.  And yes since it's high pressure TBI, I'd think the fuel delivery will be just fine with once caveat.  The Sniper injectors are on the high pressure side of the throttle plates, correct?  On rapid closing of the throttle, you might get a small dribble going back 'up' the intake direction as any mixture in the airstream 'bounces' off the closed throttle plate, and then not much help from gravity to get it back 'down' towards the head, but I don't think this will be at all significant nor cause any problems for you.

11 hours ago, jimk said:

You need to know the firing sequence for the injectors or it could have an intake pulse of air with no fuel.

I've given a LOT of thought to this topic as I still have a Lynx manifold keep thinking about trying it one day with a DCOE-style TB and Megasquirt.  My conclusion so far is that it should probably work, but injector sizing is critical.  Here's what my first attempt will look like if I ever get around to it:

1.) 2x 42# 'green top' Bosch injectors would be the right size to start; should flow enough for 150HP without making the idle injection times too ridiculously short (by my calculations it'd be about 1.75ms, slightly less than the recommended 2.0ms unfortunately, but probably still OK)

2.) Megasquirt configured for 4-cyl semi-sequential injection, bank 1 for cylinders 1/4 and bank 2 for cylinders 2/3.  Since the Lynx ALSO ties together these cylinders, one injection squirt every 360 right at TDC will mean that one of the paired cylinders will then be on it's intake stroke and thus take the whole gulp, and then the opposing cylinder will get the next gulp 360 degrees later.

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The injector size is about 60 lbs, the injector pulse now is 1.7 at idle(ish). But because it is a continuous injection system, and not pulse programmable, so I may be at a disadvantage. 

 

A single DCOE Jenvey may be interesting.  But if you are going through the trouble of converting to a standalone EFI system I am not sure that saving the cost of a second Jenvey will really matter. 

 

I am kinda stuck on the Halltech, maybe because I watch too much Youtube, but there is a good support community.  Holley Dominator would be overkill for such a small (non-drag) car, maybe I haven't really looked. 

 

The halltech alone will be about $2500-$3K cdn to my doorstep with the bits and bobs to make it work well.  Manifold and Jenvey will be at least $3.5K to my door.  I will probably save about $800-1K by going single DOCE/TBI. 

 

This is all pie in the sky,  I am mainly focusing on the 12th where I actually get it on a Dyno and get a "pro" to take a look at it and tune it.  Not sure what I am going to get, although I get the sense that I may be teaching him/her on the finer points of tuning this 2BBL EFI

 

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3 hours ago, Dudeland said:

But if you are going through the trouble of converting to a standalone EFI system I am not sure that saving the cost of a second Jenvey will really matter.

This is basically true, but I'm just considering it because 1.) I'm already running Megasquirt, 2.) I have a Lynx sitting in the garage, and 3.) I don't think anyone's tackled this particular setup yet, so might be a fun challenge.  But yeah if you're starting from scratch, might as well go dual TBs.

Truth be told, there is one reason I haven't actually plunged on this project yet, and that is because current MS2/Extra code won't let you run semi-sequential with EDIS; and I still really like my EDIS! Still, maybe one day. . .!

 

Sorry for the sidebar, back to our original topic; what was it again? :P

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(edited)
8 hours ago, AustrianVespaGuy said:

(by my calculations it'd be about 1.75ms, slightly less than the recommended 2.0ms unfortunately, but probably still OK)

Do you include injector dead time (latency) in your calculations?  Dead time varies all over the place for different injectors and is affected by supply voltage.

Dead time affects the idle much more than a higher loads.

Edited by jimk

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(edited)
On 7/5/2019 at 6:31 PM, jimk said:

Do you include injector dead time (latency) in your calculations?

Yes, at least I think we're talking about the same thing.  My 1.75ms includes the ~1.0ms it takes for the injector to fully open, then an additional 0.75s of fully-open spray-time.  I always use 1ms for opening time for Bosch injectors.  But that's why I want generally want to see at least 2ms of total time at idle. to minimize the impact of any fluctuations of that opening time latency.

Edited by AustrianVespaGuy

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My pulsewidth is somewhere between 1.75 and 1.95 M.S.  Flowing about 3.5 lbs/hr at idle.  

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I may have fixed the pinning lean immediately after I take my foot off the throttle.

The crank trigger is making this thing sing the song of my people beautifully. It has also completely solved my somewhat laboured cold start . Literally I just touch the key and she fires, hot or cold really.

I pulled back on the iac parked position to 14% from about 30%. And she wants to keep under the 21 afr reading. Now she keeps to about 13-14 % on deceleration , greatly reducing the crackle and pop.

Still didn’t solve my overrun issue.



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