Bukwild

yeah I guess its stronger but it will help update your factory crap. I am going to also do the entire stock dash. I figured if I cut in into 2 pieces it will be easier. The dash should drop 30lbs easy

muythaibxr

I'm not megasquirt god, I grounded jason's megasquirt wrong, so that has been the source of all our problems :P

Stupid crappy rx7 chassis grounds..... anyway, Saturday morning I'm going to take the ground wires that jason is running STRAIGHT FROM THE BATTERY, and solder those up to the megasquirt grounds, then ground TPS, Air temp, and Coolant temp straight to the megasquirt.... thereby eliminating the chassis from the grounds completely.

I think our tuning problems are related to the fact that the sensors are reporting temperatures that are waaayyy higher than they really are (poor grounds)... and the fact that the megasquirt isn't grounded that well (chassis ground) so the injectors might not even be opening right... that would explain why the fuel table so far has had much higher VE numbers than expected to make the car run right. It would also explain the intermittant nature of all the problems. Sometimes the car runs real well, and other times, it runs like crap... If a ground is intermittant, that explains everything.

After I get all the ground issues worked out 1) I'll never try to use a chassis ground on any car again for a megasquirt, and 2) I'll regenerate the fuel table and start over tuning with a clean slate.

So hopefully by the end of the weekend we'll have jason's car pretty much daily drivable... I don't think it's worth tuning high revs or full throttle until we can open his aux ports and actuate the vdi.

muythaibxr

oh yeah, and myk, I'm probably going to teach jason everything I did on his car, and let him help you, and only get in on it for hard stuff. Pretty soon I'm going to need time to work on the hachiroku again... It's getting a silver-top 20v 4age, and a new engine wiring harness, and I have to build some other circuits for the ignition and vvt, and the ISCV (PWM modulated 3 wire). The suspension for it should be coming soon too (7KG/mm coil-overs with AGX's and camber plates in the front, TRD 6KG/mm racing springs and agx's in the back, all new 4-links/panhard, new bushings for the front, strut tower braces, etc....) and we're going to install that... and the car needs body-work and a paint job, need to strip the interior so we can get a roll-cage welded in... sparco seats, new steering wheel, I'm going to re-design the dash gauge cluster....

So yeah, Julian and I are gonna be busy... plus we have to tune the engine with the megasquirt after its installed.

krautrocket

DO NOT ELIMINATE THE CHASSIS GROUND

very often the ECM reads chassis ground as a reference...

you ned to have proper reference voltage or you'll fry something BAD

AkumaKuruma

chassis ground comes from the battery already...running straight from the battery just eliminates the resistance the chassis naturally has and also provides for a much cleaner signal.


and the reference voltage is handled by the battery....if you run stuff from the ALTERNATOR...its not buffered and thats when stuff can fry.

you also wanna push for a common ground for the electronics too. its bad to do half off the battery directly and half off the chassis. that can do stuff just like what kens getting with jasons megasquirt (sensors being off from expected norms)

CokeRx7

all i need you to do is make a CF Corner vints.. They are very hard to find.. and take out.. i tried taking one out in the junkyard and cracked it.. it was the onlyone left!!!! so now i must wait until they junk another rx7.. :-(

muythaibxr

The stock computer wasn't connected to chassis ground at all, it was connected to engine ground...

Nothing is going to fry from what I want to do, I'm just isolating the megasquirt and sensor grounds from everything else to avoid weird problems.

This was an intermittant problem, like sometimes things would work and sometimes they wouldn't; that kind of situation is almost always due to bad grounds... and I was stupid for not just running the sensor grounds straight to the megasquirt, and running the megasquirt grounds straight to the negative terminal of the battery in the first place. Once I do that I'll have some nice, clean grounds...

EDIT: Oh yeah, and also, there isn't a stock ECM anymore... the megasquirt handles everything... so I want the sensors and megasquirt to have the same grounds... I don't like intermittant problems, because they waste my time, and are hard to debug.... like the temperature sensor problems, they only showed themselves when the engine got hot, because as the sensors get hot, their resistance drops, making them more suceptable to weird problems like this. Also, like I said, I don't even think the injectors were opening for the commanded pulse-widths, because in certain situations the engine ran well, and didn't stall, and then in others, it ran like crap, also in certain situations, the acceleration enrichments made the engine rev beautifully, and in other situations the engine would stumble with the same settings....

Long story short.... I'm going to fix the grounds, and redo the fuel tables.... and by sunday night, come hell or high-water, that car will be better than stock at least for revs up to where the aux ports would normally open.

eage8

iTrader: (9)

they are like $15 on mazdatrix if you want to pay that... I got a new one and it's nice

Bukwild

"all i need you to do is make a CF Corner vints.. They are very hard to find.. and take out.. i tried taking one out in the junkyard and cracked it.. it was the onlyone left!!!! so now i must wait until they junk another rx7.. :-("

Actually it would be more work than its worth. I already plan to make a CF dash and then you can buy the new vents in grey or black and insert them into the CF dash and it will offset the pattern and look sweet as hell.

YF19

I had a set of triangle vents and cracked them. the right vent had almost all the vanes destroyed and i think the left vent only had 1/2 the vanes left and the main ring was broke. my buddy does plastic model planes and he's got this plastic glue ... this stuff is BEAST. I put all the pieces back together again and 10 seconds, done. sanded down the glue that oozed out and sprayed both vents with that interior plastic spray - duplicolor. Looks brand new.

Just a warning about the duplicolor. that stuff STINKS. make sure you do it completely outside. even if you do it in your garage or a "well ventilated area" as recommended, it'll still stink the place up. it's really foul stuff. i have no idea how you're suppose to do complete dashes and door inserts and all that.

AkumaKuruma

cant be any worse than me painting my engine block in my basement :P:

krautrocket

i was just going on knowledge from projects ... mostly domestic ... where there can be slight variances between the potentials of the negative battery terminal and the body from static buildup ...

just as a safety measure you probably would still want to have the body tied into the ground loop somwhere

Bukwild

anyone going to the Redsox O's game tonight. I went last night and it was a sweet game. Also will be hitting the bars tonight after the game. Mothers bar in b-more has dollar long necks until 12.

DarkAngelKamui

Nah, baseball never was my thing...

Bukwild

Terry Tate rip off. Funny tho

http://studentweb.maconstate.edu/fsa...cpt_wedley.wmv

muythaibxr

But if NOTHING is hooked to the body ground except things like lights and stuff, I shouldn't have a problem... the megasquirt, all the sensors, and everything the megasquirt controls will all be grounded to the same place... I don't want any of the "static buildup" interfering.

Thanks though, I understand what you're trying to say, but like I said, I don't want anything but wire between the megasquirt, sensors and the negative terminal of the battery.

YF19

hey all,

if anyone knows of a place that does custom exhaust work let me know. the guy I went to for my 7 back in the day closed his shop =(.

* shop open on saturdays
* has mandrel bender

thanks.

falnfenix

hey Cal - did you know that your buddy Chuck has taken over half of the old PT shop? why don't you pop in there and see if he can help you out?

YF19

hmm you well .. you know he re-welded jon's HKS system. heh.. to the FRAME!! haha.

it's actually a good thing too because someone tried to jack his wheels and one of them fell off on 695. the only thing that saved the car was the exhaust. go figure.

redneck engineering =)

falnfenix

holycrap...someone tried to take the Longchamps?!?

F1blueRx7

iTrader: (5)

Extreme exhaust and muffler right on cresswell Road in Glen burnie. Well... Corner of Cresswell Road and Ritchie Hwy. He does all the exhaust welding I need done. If you are interested I have an apexi' n1 and racing beat downpipe/ presilencer for sale. I'm asking 450 for the set and it's completely bolt on.
pics:
https://www.rx7club.com/showthread.p...page=307&pp=15

YF19

Yea someone tried to snag the longchamps.

where's cresswell? if they open on saturday, i'll give them a call at work and ask them what they charge.

falnfenix

good god...he must have been pissed when he found out...

krautrocket

germantown meineke...

talk to andrey or bob... both really good friends of mine... great guys too mandrel bender and custom exhausts all the time

Tenacious

If anyone stole my FD I'd probably go on a killing spree(I'm serious), AHHH PITY TEH FOOL!