yay! finally got it dynoed! Please review.

C

cinstral

SCCoA Member
Max Power: 212
Max Torque: 314

Chassis Dyno

I have done: headers, hi-flow cats, flowmaster cat-back, and a 10% OD pulley. Do these numbers look about right for these mods? Why does the HP drop off so fast? Is it the inefficient blower?

<p><img border= "0"src="http://a9.cpimg.com/image/17/BE/14036759-e753-02000180-.jpg"></p>
 
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Your Mods..

You still running a paper filter and stock MAF??? You have a 10% pulley, I think you are good to go paired up with headers and free exh...Depends on your PSI...WHat is it? You need to get rid of the stock MAF and filter sys....I think it is gonna compliment your other MODs....

Cheers
 
You didnt have a wide band O2 sensor put on the car during the pull did you? I would have to put my money on a weak and tired fuel pump.
 
that graph is a little small to read, but I believe the falling curve is your torque, the smooth one is HP. There is no way you make peak HP at 2800 RPM's and still made good power.

Brian
 
Brian does have a valid observation, guess its possible the dyno shop reversed the #s. That still is a pretty steep torque falloff though.
 
Torque curve falls off...

Yeah,
That's the torque curve peaking at around 2,800 rpms and then falling off....normal.

Torque numbers are listed on the right of the graph and HP on the left. RPM is read from the bottom.

Everything looks fine to me.
 
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Should the numbers maybe be a bit higher with those mods ?? How many miles are on this engine ?



cheers
Ed Nicholson
SCCoO
 
Ed, my experience has shown less of a fall off on the torque curve on other cars, that though is based upon the graph actually having the listings backwards. If its correct then there are some serious HP issues. Either way, there is the appearance of a problem there IMHO.
 
It's normal!

Your curves are completely normal looking!

Perhaps what looks visually skewed is that your dyno operator waited until 2,600 rpm to tromp on your gas pedal. WHY?
This is causing about half of your torque curve to be cut off from the graph.

Normally, the dyno person tromps on the gas and does a printout starting around 1,500 rpms for our cars.

On a SC, the torque will PEAK around 2,600 to 2,800 rpms (as shown on your graph) and HP will PEAK at 4,500 to 5,000 rpms (also as shown).

Your car is typical for one of those mods. All systems normal.

The dyno operator should of started the printout earlier, at perhaps 1,500 rpms for visual clarity.
 
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212 Max power???

212, seems a little bit low. Do you know what you ran stock?

I had my 95' dynoed in 83degree weather this summer and I made 207 RWHP. That's stock except for the aluminum drive shaft.

The dyno operator told me that most of the stock 94-95 Sc's run about 200rwhp and the earlier ones arounf 190-195hp. I figure that the aluminum driveshaft gave me around 7hp to the rear wheels.

You've got a 10% and highflowing exahust. That's gotta be worth 30hp right there at least. But as paul mentioned, you could be running into a tuning issue.
 
the numbers seem good. My 94SC made 207RWHP with no mufflers and a tune. If you had a manual trans I would say they are a bit low, but for an auto, they are fine.

As far as the reason for the higher start, he has an AOD. You can't jump on it that low or it will downshift to second. Even on the 4R70W's, I have to actually use the computer to lock the transmission in 3rd if I want to make a pull below 2600rpm's.


Brian
 
If you haven't gone to a larger MAF yet, you need to. You have a free flowing exhaust and are overdriving the blower. Get a bigger MAF, like a 76MM C&L. That alone might net you 10+rwhp.
 
I've seen some 90 SC's run 199-200hp on almost stock trim. Seems like it should be higher, especially with the exhaust and the pulley.
 
The car runs a 14.5. It doesn't have problems. You could probably tune another 10 or so HP out of it, and it needs more air. That's it.
 
first, thanks for the input.

you guys are right about the curves the one that falls of is the torque :mad: the car has 43,000 miles on it. and yes because of the AOD he couldn't romp on it until higher in the rpm range. peak psi is about 11 - 11.5. and yes, paper filter and stock maf. i didn't know it was that big of a restriction. does the torque really fall off that fast?! that's a bummer. here are all the graphs, including A/F. they are choppy because they couldn't get a good tach reading. bigger versions are linked right below.

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http://members15.clubphoto.com/_cgi-bin/getImage.pl?imgID=14085507-b0ed&trans=

14085509-9bbd-0200015C-.jpg


http://members15.clubphoto.com/_cgi-bin/getImage.pl?imgID=14085509-e682&trans=

14085511-1364-02000163-.jpg


http://members15.clubphoto.com/_cgi-bin/getImage.pl?imgID=14085511-371e&trans=

thanks again for all the feedback.
 
The stock MAF is about 55 MM, and the stock TB is about 63MM, so you can see that the MAF is the biggest restriction. You could use either a 73,76, or an 80MM C&L, but since a 75MM TB is the largest you can run on the stock plenum, there is no point going above 76MM. The MAF runs about $135.

Your AF is a little rich, so again, I think there is about 10rwhp to be gained by picking it up to 12.5:1, but this requires either a chip or an EEC tuner.

It does seem to be leaning out on the top end, so I would suggest that you get a fuel pump upgrade as well. A 190lph is all you need unless you want to get really serious in which case a 255 forced induction pump is in order. A pump will run you about $110.

Nice car! 43K miles!? :eek:
 
I would definetly say you have some kind of tuning issue. My 93 dyno'd stock with a panel K&N put down 199 at about 12-13.5 PSI. I replaced my blower belts, and they don't slip(evidence to stock blower pully). How could yours do 11 PSI on a 10% pulley.....
Good Luck.
 
The reason the boost is lower is do to the less restrictive exhaust. His 11 psi is probably a more accurate boost reading then your 12-13.5 psi reading as you are more then likely reading alot of backpressure.
 
HEADS

That boost has to make it past the heads first so the EXH is only gonna help you so much bringing the boost levels down with a smaller pulley...I would say 11psi with those exh mods is pretty much right on since he is sucking air from a paper bag with the
sh!tty filter and not much more than a slurpy straw for a MAF...Good numbers, and lot of room left for improvment...I think the boost would go up with intake mods and down again with ported heads...LOL...Anyway...I think I said pretty much that in short in the first response...

BTW I have a late model MAF if you can't afford a C&L...I could even cut and drill it for ya...e-mail me..

Like DAVE said...Very sweet CAT bro...Fresh

cudaz101@yahoo.com

lata
 
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