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EFI Megasquirt help available

I have an A15 in the car- I was told that the Sentra just turned the engine sideways but if it is an E engine in the Sentra then It isn't a direct dropon injector manifold.
I was trying to get a bit more power and economy with the megasquirt but that may not be reality.
Thanks for the info- this is great!
BillM
 
Hey Glen,

What are you using for injector bosses? Looks like a brass fitting of some sort.
 
I can second most of this info, as I have the MSII on my 1275. I may upgrade to the MSIII when I finish installing the twincam BMW motorcycle head, since it has an extremely short intake runner, basically direct injection into each of 4 intake ports.
The relay board is a visual disaster, not something you want others to look at.
I'm still battling tuning issues on my car in stock 1275 form, and a lot of it may have to do with timing chain slop, a poor injector choice, and possibly fuel pump issues. The thing starts randomly "skipping" and cutting out at higher rpms when driving, as if the fuel pump is cutting out or the injectors are too small. All the new changes by Spring may bring an end to those problems (and start a whole new series).
Thanks for all the pics - they are a great help!
 
Jeff, can you post up what you think are useful links about the head conversion? I too have been considering going to EFI, even bought the kit, but have been concerned about the Siamese ports complicating things on a NA motor. One question about the BMW head: which side is the exhaust on?
 
Boy, when Jeff comes on here looking for help. WAVE...
 
Billm said:
I was trying to get a bit more power and economy with the megasquirt but that may not be reality.
BillM

I don't see why not. Everyone that I've heard so far says they got both.

What are you guys doing for relays?
 
Well, I've been resisting getting into the 21st century but am curious. I know that programable fuel injection is mainly responsible for the power, economy,and longevity of the modern vehicle. My main problem would be the "progamable" part. I'm currently running a A15 datsun engine,single HS6 SU on a homebuilt manifold and 5 speed trans. I have very acceptable power and fuel economy right at 40MPG. I like this setup so well that I have collected the parts to do another. It will be an overbored A14 and I was thinking maybe supercharged. So, my question for now would be how much power and fuel economy gains could I expect with fuel injection. Anyone hazard a guess??

Bill, do that Datsun so I can copy it!!!

(BTW the 310 put the A engine sideways. Sentra's were all E engine's but an E engine will bolt up to a earlier trans. Block is about the same. Also there was a fuel injected A engine but I don't believe it was sold in the states.)

Kurt.
 
Kelly, you only need two relays... actually, you could get away with one but not recommended.

Jeff, it sounds like the problem you are having may be "resets." Try putting a noise filter on the MS 12v in line. Also, double check all your grounds. Oh, and also, check your alternator output when you are getting the skips. The MS will reset if the voltage goes too high. I had an alternator with a bad regulator that would put out over 14v when I revved it hard. This would cause the MS to reset.

Nomad, honestly, if you are happy with the power and economy you are getting, installing an MS will probably be a lot of work and money for a non-spectacular gain. It's hard to beat 40mpg AND get good power. But if you want a challenge that will teach you a lot about how modern cars work... go for it.
 
Morris said:
But if you want a challenge that will teach you a lot about how modern cars work... go for it.

I own a Midget cause I'm trying to forget.
 
Morris said:
Kelly, you only need two relays... actually, you could get away with one but not recommended.

.

I know but where'd ya put it? Is it just flopping around? IIRC, they make a box for the relay kit. I have all three. I'll have to check. As far as not looking at it, it can always go in the glove box or under the dash.
 
I use these to mount my relays.

https://order.waytekwire.com/productdetail2/M50/75280/STANDARD%20RELAY%20CONNECTOR/

I love em.

It's up to you whether you want to use the relay board or not. They are not necessary and they take up a lot of space, but many people report that they greatly simplify wiring. IMHO the pro-built wiring harnesses are cheaper, prettier and almost as easy. But if you like and want to use the relay board... get after it.
 
Morris said:
I use these to mount my relays.

https://order.waytekwire.com/productdetail2/M50/75280/STANDARD%20RELAY%20CONNECTOR/

I love em.

It's up to you whether you want to use the relay board or not. They are not necessary and they take up a lot of space, but many people report that they greatly simplify wiring. IMHO the pro-built wiring harnesses are cheaper, prettier and almost as easy. But if you like and want to use the relay board... get after it.

I use relay connectors too but mine come with tails too. very handy.
 
Morris said:
Kelly, you only need two relays... actually, you could get away with one but not recommended.

Jeff, it sounds like the problem you are having may be "resets." Try putting a noise filter on the MS 12v in line. Also, double check all your grounds. Oh, and also, check your alternator output when you are getting the skips. The MS will reset if the voltage goes too high. I had an alternator with a bad regulator that would put out over 14v when I revved it hard. This would cause the MS to reset.

Good info! There are grounds EVERYWHERE!!! I love grounds. They overlap each other in kind of a "spiderweb" network. Rendundancy is good!!!

I wasn't aware that 14V is the limit they can handle. Most alternators will pput out 14.2 or so. I'll check that out and see what I can find. Does MS sell the filters??? Electronics design is WAY beyond my field of expertise. I am going to go to a double shielded plug wire set and figure that will help reduce any RFI pollution. I also have a spool of shielded 2-wire for the sensors.
 
The "noise filter" is just a a radio RFI filter. I reused the one that was hooked to the old burned out radio that came with my car. You can typically pick them up at Radio Shack or your local big box autoparts store.

IIRC, mine was resetting when the alternator topped 14.8. So I was not being completely accurate when I said 14v was the limit. Regardless, replacing the alternator fixed the problem.
 
In my case, the car came with a replacement alternator that I know nothing about. I think its a Bosch derivative of some sort. Sounds like the same type of issue I see with Pertronix kits - they flake out at high voltage. I was contemplating using one of those tiny lawnmower alternators anyway, so I'll see what I can find...
Thanks!!!
 
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