EDIS and/or megasquirt roll call

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vandor
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Re: EDIS and/or megasquirt roll call

Post by vandor » Thu Oct 19, 2017 2:10 am

We did the programmable FI and individual throttle bodies on Jeff's engine and found that tuning with a TPS and MAP sensors with hot cams is nearly impossible. The cams produce so little vacuum that the MAP sensor is useless, so it's impossible to make the AFR correct in all the possible rpm and load ranges. Would be ok on a racecar, but a pain on a street car.
Ended up going to 44IDFs, the car pulls like a train.
Csaba
Parts: http://www.autoricambi.us
Cars: http://italiancarclub.com/csaba/Fiat.html
'71 124 Spider, much modified
'72 124 Coupe, new project, ex-Pete, ex-Eli, ex-Jack car (all Mira members)
'73 124 Wagon, no floors
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cgranju
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Re: EDIS and/or megasquirt roll call

Post by cgranju » Thu Oct 19, 2017 10:47 am

Certainly not what I'd prefer to hear, but thanks for the feedback.
Chris Granju
sunny East TN
owner of a number of Fiats built prior to 1986
TurboPininfarina
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Re: EDIS and/or megasquirt roll call

Post by TurboPininfarina » Mon Apr 09, 2018 11:59 pm

Been there, done that, got the t-shirt, apply for the tattoo...
With 40-80 cams and turbo intercooler.
Pull like an empty train.
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miker
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Re: EDIS and/or megasquirt roll call

Post by miker » Wed Apr 11, 2018 12:40 pm

Csaba- do you think your project would have been tunable with stock cams? Did y'all keep the parts ;)?
MikeR (mirafiori.com since 1995)


1977 Fiat 124 Spider
Previously owned:
2012 Fiat 500 Prima Edizione #236 (now owned by my son David)
'86 Bertone X1/9
'81 Fiat Spider 2000 #236
'78 Fiat 131 four door
'76 Fiat 128 4 door
'74 Fiat 128 4 door
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lanciahf
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Re: EDIS and/or megasquirt roll call

Post by lanciahf » Sat Apr 14, 2018 2:47 pm

Chris if you get a pulley and sensor fabed up, would you mind having another one made?
Thanks

cgranju wrote:
Thu Oct 19, 2017 10:47 am
Certainly not what I'd prefer to hear, but thanks for the feedback.
Ralph DeLauretis
1977 Scorpion, #1409
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joelittel
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Re: EDIS and/or megasquirt roll call

Post by joelittel » Mon Apr 16, 2018 8:59 pm

I’ve got the VAS Megasquirt setup in mine.

I kept hearing that the stock Bosch FI would keep my mods from reaching their full potential so I pulled the trigger.

Even with buying the prefabricated kit the learning curve is steep... unless you enjoy tinkering with your car I’d advise against Megasquirt.

There’s no real roadmap to follow but there’s an enormous amount of information out there. It’s very easy to get lost in it all.

The real disappointment is that you need a Mustang dyno to make any sort of improvement to the tune. The seat of your pants is only so sensitive and at some point you can no longer accurately assess the cars performance without actual data.

But I do enjoy “tuning” and de-tuning my car regularly.
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vandor
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Re: EDIS and/or megasquirt roll call

Post by vandor » Wed Apr 18, 2018 12:24 am

miker wrote:
Wed Apr 11, 2018 12:40 pm
Csaba- do you think your project would have been tunable with stock cams? Did y'all keep the parts ;)?
Yes, it would be tuneable with stock cams, but if one is using stock cams then what is the point of programmable FI? The stock Bosch system will be able to keep up with any power upgrades short of forced induction.
Csaba
Parts: http://www.autoricambi.us
Cars: http://italiancarclub.com/csaba/Fiat.html
'71 124 Spider, much modified
'72 124 Coupe, new project, ex-Pete, ex-Eli, ex-Jack car (all Mira members)
'73 124 Wagon, no floors
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vandor
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Re: EDIS and/or megasquirt roll call

Post by vandor » Wed Apr 18, 2018 12:29 am

joelittel wrote:
Mon Apr 16, 2018 8:59 pm
The real disappointment is that you need a Mustang dyno to make any sort of improvement to the tune. The seat of your pants is only so sensitive and at some point you can no longer accurately assess the cars performance without actual data.
Are you kidding, it is not pre-programmed for the mods? I would think for that kind of money if would come programmed for whatever mods you also bought.
Csaba
Parts: http://www.autoricambi.us
Cars: http://italiancarclub.com/csaba/Fiat.html
'71 124 Spider, much modified
'72 124 Coupe, new project, ex-Pete, ex-Eli, ex-Jack car (all Mira members)
'73 124 Wagon, no floors
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joelittel
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Re: EDIS and/or megasquirt roll call

Post by joelittel » Wed Apr 18, 2018 8:07 am

Caaba,

I see your point. It did come programmed, but there’s no way for it to have come programmed for my car with my mods.

You’re right, it was ridiculously expensive, but I chose to pay for their R&R vs learning to build up a system from scratch.

In hindsight saving the cash to make the purchase probably took as long or longer than learning to build up an MS board on my own would have.
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Re: EDIS and/or megasquirt roll call

Post by jseabolt » Wed Apr 18, 2018 10:40 am

It seems any kind of modification to the engine will be overridden by the O2 sensor. In other words if the O2 sensor detects an abnormal fuel mixture (say too rich) it will cut back on the duty cycle.

This was the problem I had with my turbo system. I'm using an adjustable riding rate fuel pressure regulator to bump up fuel pressure as boost increases but the O2 sensor picked up on this and kept trying to lean the mixture out. The simple fix was to place a pressure switch between the ECU and O2 sensor and disrupt the signal under boost.

I don't know what would happen if you installed a hot set of cams or higher compression pistons. Maybe the same thing might happen.
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