areXseven

iTrader: (1)

I'm buying a center speaker dual gauge pod next week and decided to get an A/F Gauge, but don't know which other gauge to buy. I already have a dual a-pillar pod with a boost and fuel pressure Autometer "sport Comp" series gauges.

Thinking about buying a Tranny Temp Gauge,...or..???

What would really be sick is if some Company would manufacture/sell a round (52mm) Radar Detector that could be placed in the pod??? (time to visit my Patent Attorney )

BicuspiD

scrap the A/F gauge (they are worthless) and get water temperature and oil pressure

Sprockett

Exactly - water temp and oil pressure. Really, there's no use in having gauges that don't tell you anything (unless you like pretty lights)

areXseven

iTrader: (1)

My stock H20 and Oil pressure gauges works pretty good. So, no need to buy aftermarket. ???

elfking

Your stock water temp gauge shows Cold, Operating temperature and YOUR DEAD temperature... Having an after market one with its own sensor and with actual number readings will show you a much finer reading of those inbetween temperatures. You will be able to compare it alot better for when times are not so good.

Same goes for the Oil pressure Gauge. Personally im going to pick up EGT, Water Temp and Boost. Those seem to be most important for these cars. maybe Oil temp but I don't like having gauge pods so 3 gauges is the max (bottom stereo din.)

rynberg

EGT is just as worthless as the A/F for 99.9% of situations.

The stock water gauge is useless. The stock oil pressure works fine if your sender is in good order.

I run water temp, boost, and oil temp, all useful and necessary for track driving.

areXseven

iTrader: (1)

Well, my FD is automatic so I was thinking of installing a Tranny Oil Temp gauge. Our FDs don't have a Voltage gauge so I think I'll install a Volt Gauge in the pod along with the Tranny Oil Temp gauge.

FDNewbie

iTrader: (10)

Rynberg, why is an EGT gauge useless? I thought it helps tell you if you're running lean or not...

areXseven

iTrader: (1)

Problem solved. Just ordered a tranny temp and voltage gauge. Thanks for the input guys.

rynberg

Ok, say you mount an EGT gauge. After a hard run, you see it reading 1500F. What does that mean? Exactly. Nothing at all.

The EGT varies little with a/f ratio. It is also extremely slow to react. About the only time it is ever going to tell you something is if it starts reading REALLY high, in which case it's too late anyway.

Read this from SBH Motorsports:


Why not tune AFR based upon EGT (Exhaust Gas Temperature)?
You can only get a general idea of AFR based upon EGT IF, and only if, you have correlated your car's AFR with its EGT under a given set of conditions. And even at that, you can only get a general idea of the AFR. You can not tell with accuracy just where the AFR is. Perhaps at best you can get within a full point or so, and that's not very close.

Here's an example of the variation in EGTs from car to car. Several months ago I helped tune 3 single turbo Supras on the same day on the same dyno using the highly regarded Horiba wideband O2 system. All 3 cars were tuned to about 11.4:1 AFR across the boost and RPM range. Peak EGTs ranged from 770 to about 880 C on the various cars according to the GReddy gauges (one car's EGT at 770, one at 790, and one at 880). All 3 had GReddy EGT gauges but with identical probes mounted in different places. The coolest EGT reading was from a probe mounted in the #6 runner, the middle temp one was mounted in the front passenger corner of the collector, and the hottest reading came from a probe in the center of the collector directly under the turbine inlet. This in itself proves that EGT readings can not be trusted because there is no physical way that the EGTs in the collector are actually hotter than those in the runner close to the combustion chamber, but this is a function of heat-sink effect happening with the probe and we won't get into that concept here.

If one were attempting to tune the above cars based upon EGT readings, what would he have done with those 3 cars? Conventional wisdom says that EGTs of up to 900 C are allowable prior to the turbo on most turbo motors. If the 770 C car were leaned out to approach 900 C, the AFR would have been in the 15:1 range! That could prove disastrous for an engine running boost. A similar circumstance exists for the car indicating 790 C. What about the one with the 880 C readings? Would that car be dialed back a bit richer because the 880 C readings are approaching the generally accepted MAXIMUM of 900 C? If so, that car would probably end up in the 10.5:1 range and needlessly sacrifice power.

Perhaps the biggest downfall of EGT as an AFR tuning tool is the fact that there is no possible way for an EGT monitor to react quickly enough to spot lean and rich spots in the RPM curve. Most engines will exhibit an AFR curve that varies a good bit throughout the RPM and boost range. At best, EGTs can only give you some indication of peak temperatures. It is not possible for them to point up a dangerously lean area spanning a few hundred RPM somewhere in the range (even though many cars exhibit AFR curves of this sort that need to be tuned to flatten them out).

The bottom line is that EGT readings don't really provide much useful information when it comes to AFR.

FDNewbie

iTrader: (10)

Rynberg...thanx a lot for the info. So it's basically like the stock water temp gauge.. . either you're cool, or your screwed haha

Now im in a bind...cuz basically I should chuck my absolutely BRAND NEW EGT gauge?? =(

FD_Newb_1974

I rarely have EGT's over 700c, in fact I have a warning on the peak hold @ 760.

For daily driving my temps stay right around 650 in higher gears. I do notice the gauge reacts fairly quickly to changes in RPM's and throttle, ALMOST instant.

At WoT my actual temps start to come back down after peaking..my understanding is this is how correctly tuned cars should run.

Now, if for some reason my EGT's vary, I know I have a problem...simple trending over time.

While I don't tune using the gauge, I find it useful to monitor the daily characteristics of my car. As I do boost, water and intake temps, engine temps, and fuel pressure.

Next for me would be Oil Temp and perhaps a peak hold boost gauge as I am currently using PFC.

FDNewbie

iTrader: (10)

That's exactly what I wanted it for... not for tuning...rather for monitoring. Rynberg, were you saying it's too slow to react for tuning purposes, or for general monitoring as well??

And can someone explain to me the purpose of a oil temp gauge? (sorry...newbie question). Oil pressure I get.. water temp I get...but what's the oil temp gonna tell u? (im guessing/assuming the oil temps may correlate w/ engine temps just like water temps, so if you already have a water temp gauge, isn't that like having 2 gauges telling you the same thing?)

PS...FD_Newb_1974, nice screen name

ZeroBanger

I have intake temps, water temps and boost gauge.

teamstealth

i have just boost right now...planning on dumping my a/f gauge the previous owner had installed for a water temp, then oil temp/press once i get some cash. Why would you want a voltimeter gauge? Most turbo timers have that function built in.

EDIT: Checked out ur sig and noticed you have a GReddy Turbo timer. Hold the select button for 2sec, and the screen will show something diferent then your time settings, do the hold for 2 seconds until it shows VOL....thats ur voltimeter And the turbo timer will still function in the background to whatever ur last time setting was.

areXseven

iTrader: (1)

Now WHY didn't you tell me this before I ordered the friggen Volt Meter????

Thanks for the L-D. I really didn't know that!!.

teamstealth

yeah the GReddy is actually a pretty versatile little tool. It'll do digital speed readout and copy your tachometer if you connect it to the right wires and calibrate it!

rynberg

Oil temp is important for road racing. If you never track your car, it's not really necessary. And no, water and oil temps do NOT have a linear relationship -- I discovered that the single touring oil cooler isn't cutting it for track work this way.

IMO, it's silly to have several gauges. I just like to drive the friggin' car. How much can you enjoy driving if you are always busy looking at 6 different gauges? Relax and just drive the damn thing....

BTW, don't get a Voltimeter. The PFC has one as well.

FDNewbie

iTrader: (10)

Not that I need it (as compared to you) but I have dual oil coolers (R model)

And yea I def. think it's overdoing it when the interior seems more like a cockpit than a driver's seat...

I was wondering about the voltmeter.. coulda sworn the PFC has that readout...

areXseven

iTrader: (1)

Well IMO, as long as the gauges monitor different vital aspects of the engine and/or engine components, I think it's okay to install them. Overkill starts when you add gauges that monitor the same thing as the the working stock ones. Like when you add a big 5" Tach. In other words, don't be redundant with the instrumentation.

FDNewbie

iTrader: (10)

Very good point. But many time I've seen/read ppl get gauges for things the PFC monitors...

SyderJL

No offense areXseven, but for almost 700 posts I would have hoped you would have learned that the stock temp guage is worthless, just like a A/F guage. . .
I mean have you ever seen the stock temp guage move once the cars warm? I haven't.
You should send that volt guage back and get a quality water temp. gauge, I am sure you know that FD are know to over-heat and from what I hear it gets pretty hot in Texas.
Hope I don't sound like an ***. .
BTW I have a magnaflow exhuast too, SS, 3" in, dual 3" out, 3" tips sounds just right too.
Good luck w/ your 7.
Justus

areXseven

iTrader: (1)

No offense taken. Your comments are much appreciated! And you're right,...It sure do get hot here in South Texas. Our Summer of last was brutal. But my 7 never once over-heated. And the water Temp gauge never marked an above normal temp. I think (for now) it's working pretty good. Guess I'm just one of the lucky ones. I think the radiator was replaced right before I bought the car. That may explain a constant normal water temp. Also, in Corpus, we don't have the stop and go type traffic found in much larger venues. The car is always on the move(pretty fast).

teamstealth

well its not really a matter of the gauge not moving...it wont move from straight across unless you are already overheating. Meaning it wont acknowledge a change in temperature from a certain rainge (i think its 160-220...someone correct me if im wrong) so you really are blind as to what your true temp really is. So with a FD, try not to think of it as buying redundant gauges, but as purchasing one that gives you a exact figure, not just a generalization.