Just recently Dynoed my 88' GXL. I had It wired to the Leading pack and displayed, to what I believe, incorrect results. With a max power output of 113.5 and max torque of 121 something is wrong!!

Right out of the factory the motor is 146hp - 20% which gives the rear wheel output, which would be app. 166hp. Yet I am not even getting that considering I have many mods. Output wise, I have RB Header, stainless steel cat back (Brullen), Bonez Cat, K&N Filtercharger, Crane Cams Ignition Box and old but will be replaced Magnecor 10mm with RB Ultra Hots.

With the above, I should be in the 160's. Can anybody help me here?

 

i thought 146 was fwhp for a gxl

 

Yep, 146fwhp is the stock rating, which is ~117rwhp with a 20% drivetrain loss.

 

I was just going to say that NZ. I wish it was the other way around, increase hp thru the drivetrain.

C

 

Don't you guys mean rwhp (rear wheel horse power) or am i missing something?

C

 

The factory power rating for a S4 NA is 146hp, measured at the flywheel (fwhp). Approximately 20% of this is lost to the drivetrain, leaving ~117hp at the rear wheels (rwhp).

 

Sorry. Error made. Meant to say: "Right out of the factory the motor is 146hp - 20% which gives the rear wheel output, which would be app. 116.8" not 160. It's obvious the boy can't count! Any sugg. to my initial question?

 

I bet your engine has over 150,000 miles on it...



-Ted

 

did mazda ever produce that hp@the wheels? I just wonder what they said it was stock. 20% is modest figure.
how many miles are on your car, and what about compression figures?

 

Oops, got distracted...
You should always connect a tacho (or whatever) to the trailing coil, as the leading coil fire twice as often (wasted spark set-up). The trailing coil fires twice per engine revolution, just like a 4-cyl.

 

It really doesn't matter - as long as the DynoJet is set correctly for engine revolution per ignition cycle.&nbsp It's usually very hard to extract an ignition signal from the trailing spark plugs wires, so we usually run off the leading spark plug wires...


-Ted

 

RETed, I guess I should have mentioned that I have 25k on my rebuilt engine. My compression is excellent for that matter. So dynoman should wire It up to my Leading Coil you say?

 

Wanna post your dyno sheet somewhere?
6-ports not working?



-Ted

 

I was starting to wonder how Mazda arived at 146HP. I know with aircraft when they test the engines it is on a test stand, free flowing exhaust, and no acc. on the engine.

So does that mean Mazda found 146hp with that same setup?

James

 

All manufacturers quote engine dyno figures, not chassis dyno ones. It's just marketing. Would you rather say 117hp or 146hp? How Mazda tested the engines to get these figures is anybody's guess. They're sure not going to tell you...

 

Or the other possibility here is that your mods are not quite up to advertised claims.

I don't know about 160 rwhp, maybe 140-- that's about a 23hp gain at the wheel, I'd be happy with that with what you listed.

Call me a pessimist, but I've just been disappointed by most aftermarket HP gain claims. Across the board, they seem to inflate the gains.

Greg O.

 

I am not sure what your suggesting? That my mods are not correctly stated? Quit humoring yourself! I simply stated my mods I have done to my FC and suspect that either the dyno jet wasn't set right or what has been going for a year is my oil pressure has been low, at all times, which may have caused some internal damage!
Please bud! You don't have to be posting stupid replies or alligations!

 

Whoa there! You should reread that post before you stick your foot that far into your mouth!
There's nothing in there implying you lied about your mods. What he was saying was you may be expecting a bit much from your mods, and I tend to agree. Some aftermarket parts manufacturers tend to be a bit optimistic with their claims of power increases, and shouldn't be taken to seriously.

 

thats what im thinkin. So do u have them?

 

Yes, I do have the dyno sheet in front of me but I am unable to scan and post It b'c I don't have the equipment to do this. I apoligize for that outburst 10TH_ANNIV_T2 I guess my frustration to all this money I dumped into my ride got the best of me. Okay now start playing the violin....

 

Test the ports your self.

Put some grease on the slves of the actuators, go for a "Spirited" dirve and see if the gres was smeared any. If not, start looking for leaks or anythign that might keep them from operating.

With your mods you should be in the 140's with an optimistc low 150's RWHP.