ok so i blew my freshly rebuilt motor with 400 miles on it from detonation. needs more fuel. upgrade to 720's and big pump. need more fuel! add more injectors. now i need to control those injectors plus what i have. was thinking about greddy emanage blue and the greddy rebic. but now its getting expensive and for add on parts. my friend dfp22 did his own megasquirt and seems happy but my setup is a bit more wild. so i have a few questions. im not an electronics whiz at all. i get by but this looks like it could get hairy fast. is it really that hard? and what about just buying one assembled for a bit more? do i still have to do wiring? thanks. i ask these questions cause i read the faq and got a headache. thanks guys

oh yeah and do i have to keep a laptop plugged in it to make it work?

 

you don't need to keep a laptop hooked up, you can buy one prebuilt, but you still have to modify it (which is what the FAQ talks about), It's not that difficult, but you have to pay attention to everything you do, and double/triple check everything... and at least try to understand everything you do, and why you're doing it.

 

ok. do i have to solder for the modifications? and are these https://www.rx7club.com/megasquirt-forum-153/plug-n-play-ms-prototype-finished-484871/ plug and play connectors available anywhere or do you know where i can get one?

 

Isnt the new one coming out plug and play?

 

Zeal (me, tofuball, pele, a couple other people) have a plug 'n play setup on its way very shortly.

If you want to do the mods yourself, then yes, soldering is necessary.

Ken

 

hey, I said I can help you with it dude, its not so hard once you've been through it once. and being that I have gone through all the trouble once already. I also already have a modified CAS here at my house (bought an extra one for down the road JIC).
Trust me, even though yours is more "wild" its nothing that I can't help you with. Plus, I already have a base map that works well made that you can use. mabe with your higher compression, we should back off the timing around 7-15psi range. but nothing huge.
I see you're on your way to doing it right this time.

dpf22

 

fo sho! i got lucky this time but i dont want to count on gods good grace anymore. when i get it ill call you

 

Care to share that base map with me?

 

eh? well, you could pm me, my setup may work well for me, but as far as fuel, it will be different depending on your secondaries and primaries, fuel pump, etc. however, if you want it, I will pm you the msq a little later ok.


dpf22

 

so um does the ms2 with pcb3 board work for rotaries?

 

not yet. I'm working on code for that tonight actually.

 

ok here is the msq file. Keep in mind that anyone that uses this will have to activate the high res 08 code.
Also, DO NOT Blame me if your engine blows. I tuned on 87 at 4500FT altitutde. If you have any issues, use premium. My car works great with 87 but will ping if I use 85.

 

oh, by the way, this would be S4 low comp motor tuned for up to 13 psi on stock turbo. a larger turbo should possibly require more fuel, but the timing won't really change.
My injector combo is 550 primary 690 (gsl-se)secondary injectors. The staging works good for me but I may need larger primaries because of where I staged it, the primaries are running a little on the top end.

dpf22

 

arent gsl-se injectors 680? anyway i hope i have a reason to get that file soon. probably going to order my gear next payday

 

what I have always read, they are 690cc/min, I could be wrong. thats just what I have read most commonly.(fsm)

 

whatev you know it all... anyway.. my car is now under a deadline to get going. there is a drift event in june that i need to be sorted for so i can compete in it

 

Thats not even a problem dude! in fact, if you can buy a wideband for your megasquirt, I will tune it a little while you drive. I can show you a few things. Dyno tuning is overrated as it will only yield your peak numbers anyways. You want max torque over a large band.
My max torque when I went to a dyno on my blown motor was 219 and 215whp.....what was funny is that I had over 175 ftlbs for more than 3k rpm (3280-6500) before it fell off drastically. We can do stuff. Its not getting it running that will take the time, it is the tuning. I constantly tweak my car, and it has a blown motor. I will be hopefully picking up a mazda reman here within the next 3-4 weeks. We shall see the diff on a good motor after break-in hopefully.
I suggest you upgrade to a koyo radiator and a LARGE e-fan before you try to drift in the middle of june...

and yeah, I double checked myself on the injectors (in 3 different spots) its 680. ah well, can't be perfect...
I don't know it all, just more than you lol. jp

dpf22

 

i am turboing my SE i have almost everything except fuel lines, a pump, 2 more injectors, and ecu (MS). i was planing on used my 680s as secondaries but will the 550s be enough for primaries? im not going to boost anymore than 8-15psi and 15 is the max and i dont think i will go that high so yeah.

 

It's important to understand these injector flow ratings. Injectors are normally rated at 3 bar test pressure, which works out to 43.5 psi. Our stock Mazda regulators provide just under 40 psi, so any injector you buy will flow slightly less than the rated value due to that lower pressure. To determine actual flow rate, use the following formula:

Actual Flow = Rated Flow * sqrt(Actual Pressure/Rated Pressure)

As for the GSL-SE injector flow ratings, here's what I've stated earlier on that topic:

"BTW, have you had those 680's flow tested? They likely flow more like 720-730 at 43.5 psi (3bar). The whole 680/720 bit is forum folklore as near as I can tell. FSM says GSL-SE injectors flow 173 cc/15 seconds at 39.7 psi, or 692 cc/min. Multiply this flow by sqrt(43.5/39.7) to get nominal flow at standard 43.5 psi fuel pressure = 724 cc/min. This coincidentally is what's been reported by a number of users who've had them flow tested."

In other words, if you are going to buy an injector equivalent to the GSL-SE unit, you'd need a flow rating of 724 cc/min (720's are common). Running at Mazda's reduced pressure, flow rate drops to 692cc/min. I've got no idea where the 680 number ever came from. Possibly a typo by a forum god in the early days of the club, and parroted by others ever since.

 

i think renns right......ive read many times that they are 680 but a very smart guy that has a rotary shop (im not gonna name any names here just cuz i dont like doing that) that knows what he is doing said they were really 720s or somthin like that so anyway would some 550s do me if i had 720 or 680s or w/e u wanna call them as 2ndaries?

 

mabe that is where I got the 690 from. Man, sometimes I just take numbers and do self calculations. I like to do that to see where the rotary lies on different turbo maps. and as far as 550/680 combo will work for what boost you are planning on running as long as it remains on the stock turbo. once you step up in turbo size, I would suggest an aftermarket fpr to rais the fuel pressure on your 7. This at least. But since it seems they are like 720's really, that would explain why they flooded out soo badly on the midrange with the stock ecu lol.
Besides anyway, raising the fuel pressure will lead to better atomization and a possible leaner idle and better gas milage. Just a thought (did it on my friends ca18det powered 240sx)


dpf22

 

well im using twin fd turbos fully non sequential but like i said no more than 15 psi at the very max and in reality i will probly do only 10-12 so the turbos are stock lol but not FC stock.

 

I run 550 primaries, and gsl-se secondaries in my S5 turbo setup. At 8-9 psi duty cycles are up in the 70's, so they'd likely be OK to 12 psi at the most. That's a good limit for the stock turbo anyways. I'm swapping in a T04B hybrid this winter, and will use a second pair of gsl-se injectors as primaries.

 

they flow more cfm than the stock fc turbo(s), you will need a good amount of fuel. FD's use 850 secondaries. Get an adjustable fuel pressure regulator and up the pressure.

dpf22

 

how much will a pair of FD 850s cost?? and FPR and pump are what i have been looking into lately i found a slightly used walbro 255 i think? for 50 bucks and now im looking into FPR.. anyone have any suggestions? next week i plan on ordering my megasquirt and im excited yet afraid...afraid about the tuning and not cuz its MS just cuz its a turbo rotary i dont wanna blow it.