Hello all. Long time member but don't post very much. Actually just getting back into my 93 RX-7 as I was fed up with all the little problems it was having.....so it's been sitting for a bit....but now it's almost ready to go again!! (It's in the shop for a new O2 sensor and water temp sensor...the malfunctioned old ones wasn't giving the ECU proper readings and the car kept dying once it hit normal operating temperature. Sounds logical.....I just hope it works and the car runs like a champ for...like...ever after this fix!)

Down to it. I was thinking of getting 3 gauges to monitor the water temp, oil pressure, and EGT or Fuel/Air ratio. This will run anywhere from $400 to $700 depending on the brand of gauge. On the other hand, everything I'm reading about the PFC says that it can do the same thing. With the price drop to $950, if it does in fact monitor what I need, it almost makes sense to go with the PFC instead of the 3 gauge panel. I just need to know, from the PFC owners out there, if it does do this and does it do it accurately? Are there advantages/disadvantages one way or the other. Please advise.

I have a Pettit ECU right now (which I could hopefully unload for $350 or so on here, and if I can, it makes more sense to get the PFC). Other mods are Pettit cold air intake, Bonez downpipe and hi-flow cat, PFS cat-back, and RP competition fuel pump.

Thanks for reading.

 

PFC will cost you 900 new i think plus you need the tuning, i would also add a wideband also. what mods do you have in the car? are you planing any higher then the 10psi on the TT, or even a single? i fyou are then go with the pfc and get additional guages later, such as the EGT, Wideband, and oil temp.

 

I bought the PFC just purely as a monitoring tool. Its useful for certain things but when your driving, they are annoying to look at. The LCD is hard to read and reading a gauge with a needle is much easier to understand. If your that worried about your 7 (I am), I would like to see the state of my engine easily while I drive instead of checking on it periodically when I think Im running hot. The PFC has its uses and its pretty awesome but as a monitoring tool, it honestly isnt that convenient to use.

Im now getting new gauges installed in 2 weeks.

 

Thanks AZCamel and Supernaut. (My mods are on my post AZ.) I think I'm getting around 12 psi on the boost.....I'm not sure, I haven't really driven it (hard) in a while. Stock TT. Pettit ECU.

Now to follow-up: what 3 gauges would be most important? (I already have a boost gauge.) Looking to add 3 on a DIN panel once I gut out the Bose system. I'm thinking water temp and oil pressure for sure. The third being the wideband or EGT.
Also...is there really that much of a difference between brands of gauges? What are you going with Supernaut? I've been browsing on egauges.com....and they have VDO's for cheap (compared to Greddy) and Auto Meter is not too expensive either. I remember the VDO from my V Dub Scirocco days. Will I regret trying to save a buck (actually maybe $300) going with VDO or Auto Meter?

 

autometer is fine i used it before, i have greddy boost, egt, and PLX wideband along with the PFC. The PFC is not that bad to see IMO, it also has peak hold and such s you can see what you hit max, also has selection of 1, 2, 4, or 8 reading output so you can choose how much to display, of course the less the number the bigger the display is. IMO most of the guages are the same, the onlything i would be concerned is the wideband if you get it, do alot of searching before buying.

 

I ended up getting the cheapest pods and gauges I can find. I ended up with glow shift gauges. They are quite gaudy but they are pretty cheap. Ideally I wanted defi gauges with a VSD but decided against it at the last minute. I read that they woudnt work on 7s but in fact they do. I need to save money anyway.

Also, I think the consensus here is that water/oil temp and oil pressure is what your first 3 gauges should be. If Im wrong someone please chime in.

I ended up going overboard and got
AEM tru boost controller gauge
oil temp
water temp
oil pressure
AFR gauge
tachometer (I know hahahaha laaame, but it was cheap)

 

in my opinion:

1 Boost
2 Water temps
3 toss up between Oil temps and Wideband depending on how your car behaves and what you use it for and mods. Oil temps trail coolant temps by ~20 degrees according to old posts on here.

There are a few 'which gauges' threads on here so search and you'll find lots of threads and opinions on the subject.

 

I would go

1. Boost
2. Water Temp
3. A/F

 

I have boost and water temp. The 2 most critical IMO.

I wanna get a wideband sooner or later.

 

The PFC is a great mod imo, though tuning *is* needed to make the most out of it.

If monitoring the readings on the Commander is troublesome for you than I would first look at where it is mounted (if at all) as this can play a large part in usability.

I have mine mounted where the cig lighter is, just behind my steering wheel, and it is a simple glance for me. The only time seeing the readings is difficult is if you are trying to check the peak readings (a built in feature) in traffic, as it takes a moment to see the small text.

I am constantly monitoring my IDC (Injector Duty Cycle), Air Intake Temp, Water Temp, and Boost Pressure (boost pressure will read slightly off from the mounted gauge unless calibrated with a MityVac). I wouldn't change my PFC/Commander for anything!


As for other gauges, I've got:
Boost Gauge
Oil Pressure (will replace with a flow sensor for my W/I system when I get it since my stock Oil Pressure sender is fine)
Wideband A/F ratio (Innovative LC-1)
Fuel Pressure

I (personally) think those, in addition to the PFC, cover just about all the bases of possible paranoia ^_^

 

you dont need an A/F gauge unless you are tuning.. its nice to have in order to have a quick reference/warning against lean or rich settings.. but if you arent tuning your car you are not going to be able to correct those problems.

Boost
Water Temp
Oil Pressure
Oil Temp -- last.. i have this but i got it almost free...

for tuning
EGT
A/F

after those
fuel pressure and anything else.

I have boost, water temp, oil temp. next purchase will be oil pressure unless i come across a good deal on EGT. I havnt decided on a wideband yet.. leaning towards the techedge wb. if i get that ill probably get the nifty gauge they have to monitor the AF settings after the powerfc is tuned.

 

VDO gauges in my din panel. All still work very nicely after 5 years. Orange bulb covers match stock backlit colors perfectly at night.

 

That's hilarious Adam C. From my little research, I saw that VDO gauges were the cheapest around. So I'm wondering about quality vs price, even though I can't imagine them just sucking.... And BAMMM.....you show me your panel and it looks great!!!...and then I see under your name "cheap bastard". You're a walking advertisement for VDO. 5 years eh? Not baddddd........

Thanks for all the info. You're right N3, what the heck am I going to do with the readings from EGT or A/F? "oh, that doesn't look right....great...what now?" I don't even know what those numbers mean.....

I've got another question but I'll start a subthread because it's more about the PFC...

 

Still considering the PFC vs gauges as my next "mod"......

One of the websites I came across had a review (only 1....which seemed suspect) on the PFC where the poster said that it fixed his 3000 rpm hiccup.

Is this true? Is it possible? Does it do it plug and play or will it only fix it with a good tuning from an experienced tuner?

If it is, it's almost worth it right there....sometimes that hiccup is so bad it feels like I just crashed into a wall .....the stop from acceleration is so bad.......

 

You should defiintely get a PFC. Just realize IMO, you should get gauges as well.

 

VDO gauges are OEM gauges on many Porsches.

 

I would def suggest going with the PFC next.

I seem to remember mine going away when I put the PFC on. But I'd only had the car for a month (at most) when I installed the computer.. that was a couple years ago now. If you have a bad tune done on the PFC you *can* have a horrible stumble, but that is fairly easy for any knowledgeable tuner to smooth over.

The PFC is plug and play, it will eliminate that stumble without additional tuning. The Base Map is pretty safe and generally does not need to be tuned for your standard modifications (though I went from 247 to 280 (plus 18% when converted to "American" power numbers) at the wheels with my first tune) however it's a pretty good idea to have it done. Tuning the PFC will get you more power from the same mods, and (depending on what kind of mods you've got) possibly increased fuel efficiency.

I think I experienced this once, maybe twice, before putting in the PFC (Nov' 06). I've never felt it since and I didn't get my first tune until like March of this year.

 

Adam C - I wasn't busting your *****....I was leaning towards VDO because I remember it from my Scirocco days and it was the cheapest. You just validated it for me. Thanks! Ohhh, please enlighten me with your "cheap bastard" intake!

Fendamonky - thanks for the input. I just got my car back and it's running pretty smoothly right now. The new O2 and water temp sensors did the trick. The Pettit ECU may actually be fixing the 3000 rpm hiccup as well, now that it's getting proper input from those sensors....only time and hard driving will tell. The main guy at my shop also told me how the PFC fixed the hiccup on another car instantly. If the hiccup comes back, I'll get the PFC.

 

Havent read all the posts but for one guages in the din panel in my opinion are out of the way and make no sense other than when your stopped... You want to monitor them while driving and under load and conditions which I think makes that hard to do if you have to look downa dn try to focus on thema dn drive at the same time... You should try adn put them in more of a viewing area... Center dash or a pillar or steering column... As for what gauges to get your boost and temperatures are the most important... You said you already ahve boost and want 3 more... So i would go with Water temp... Oil Temp and Wideband... So youll have 4 gauges total...You can also get a multipurpose gauge which you can change between multi functions like wideband. oil temp, water temp, stuff like that..

Chris

 

and mercedes benz and volkswagon and bmw and yeah. they are nice stuff.

gettting back to it

gauges you need in this order

1) wideband (to my knowledge the pfc cannot show this in gauge form)
2) water temp (pfc has this)
3) oil pressure (not on pfc)
3.5) oil temp (not on pfc)
4) boost (pfc read this in .bar)
5) knock (pfc has this one)
6) manifold intake temp (pfc has this)

I would buy a wideband then the pfc and call it good. You could have a very nice wideband for $400 and the pfc for $900. Pay someone to install them and your car will last.

there is reasons why 7 owners have so many gauges. I agree to place them in a place you can see them all at once without searching to far from the road. Here is a pic of my set up. I can read them all (except boost control in which I have two other places to read boost pressure availible and closer to the road slight line)

 

alright jack.....thanks for the input. Lots of good info there. I do notice that you have some type of bendable commander holder thingie that looks awfully a lot like a hand...oh wait, it IS a hand. Except your last picture...is that where it is when you're driving? And what's up with the dollar bill? Yeah, I was zoning out on your dash a bit........

Got my car back and it's running very nice now. I'm going to cross my fingers because I've had it for 8 years and I don't think it's run trouble-free for more than six months at a time. Always something! I'm sure many of you have that love/hate relationship with it. Pertaining to my first post, it seems the new O2 sensor and water temp sensor got the job done, as the car is idling smoothly with only one instance of hesitation so far (like 20 miles driven). And I haven't noticed the 3000 rpm hiccup...so maybe the Pettit ECU coupled with proper inputs fixed that. I'm going to call them to ask. I'm actually excited to be driving it! But will it last........

Next thing will be the coolant I predict. As I add coolant every month...but don't detect a leak. Does this car drink coolant? It's not like my daily driver where the coolant NEVER changes? Ever? I digress......

Thanks again and I'm going to consider everyone's input. Just...do I really want to drop more money into this ridiculously seductive car?

Mad props to all those top tier rexxers out there. How you do it I don't know.......

 

I do not see the need for a wideband gauge kit if your car is tuned, do to you not being able to do **** about it when it does go lean!

Boost and water temp are defiantly the most important of all gauges when it comes to a 3rd gen RX7.

A boost gauge can aid in diagnosing turbo operation problems, possible vacuum leaks and also verify if the system is boosting and working correctly!

Water temp gauge is also a must have! the factory gauge has no numbers on it and when it starts going near the top it might already be to late and say goodbye coolant seals. A aftermarket water temp gauge can supply you with exact water temp, figure out when the fans kick on, and help keep peace of mind.

You do have a factory oil pressure gauge and it should work, mine does. If it doesn't work then I would get a aftermarket gauge kit or replace the sending unit because making sure the motor is being supplied with oil is critical!

Oil temp usually follows along with water temp so however hot your coolant is your oil is around the same range, it would be a nice gauge to have those just so you can view those temp's and know how well your oil coolers are doing theyre job and if you need to upgrade.

Anything can make the factory knock sensor say some crazy number mine has, if you detonate good chance your motor already took a **** on itself, so I really don't see much importance in this item.

Intake temp, a/f wideband, and egt gauge should have no real importance unless you are tuning the car, like I said when you see something gone wrong it might already be to late and you can't do anything about it.

 

I don't agree at all. You rank an engine overheating above popping an apex seal from running lean. I don't know how you would ever overheat one of these engines without hitting boost multiple times. If your air fuel ratios are lean you would never see the time needed to do wot pulls to overheat the motor, what came first the chicken or the egg ?

Basically they are all important. I have my car tuned but the wideband doesn't always read the same and it is nice to know when your near the danger zone. When my engine is cold it reads different, when the air intake temp is cold it reads different, same with when its hot. Its constantly changing, some days under boost it reads 9.x and then the next day it will read 11.x under boost. Its tuned that way but it is still nice to see this every time I drive and it re assures myself to go wot.

 

Yeah, I originally wanted to mount it to the right hand side and then relized it would work better where it currently is. I used some thin aluminum and bent a very basic piece to hold my commander, it just slides between the crack in the dash and holds it. Very basic and very functional and most of all was free! I get more questions about the dollar then any other piece on the car, story goes...One night I was spirited driving a 'togue' road in the middle of the night. The innovate wb gauge has a led light which is very bright, on left hand turns I'm practically blinded from the refection on the windsheild and the window, so blinded in two spots. I taped a dollar to the gauge and fold it over so I'm not blinded, it was my only piece of paper availible on that road at the time, works really well and I can still read the wb, best of all it only cost $1

 

Don't forget the cost of the tape!

And if you're really hungry without other funds on you.....you can grab something from the dollar menu. Nice thinking! You'd have to be down in Oregon though.......

Cars still running great!! FYI: I called Pettit today and one of the techs, Cam, did in fact say that their ECUs have been known to get rid of the 3000 rpm hiccup...dependent on other factors. I haven't felt it yet, since my new sensors so I would have to concur as of now. So I guess so I don't really need the PFC that much I guess. Gauges it is........for now.

Side note for amusement. I've always noticed that the front left wheel is closer to the car than all the other ones. (Lowered.) Well, I explored a bit more and wiped the grease from the spring there and it's BLUE!!! All the other springs are black!! 1) I can't believe it took me so long to notice. 2) I can't believe no one that's done work on it has said something to me!! How did that happen? Car's been in a wreck and they did a poor job fixing it? One lowering spring......go figure. Now I'm going to have to get a whole new set......