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Discussion Starter · #1 ·
I had a chance to put the Viggen on the dyno this past weekend. Unfortunatly I left the ODB reader at home so I couldn't record timing and boost data. This will serve as a baseline as I start doing power mods.
200K JPG -
http://abecovello.com/images/turbotaxi.jpg

I'm happy with the numbers, although the A/F curve has me a bit worried, but it wasn't pinging at any time, so I guess its not too bad.

Dyno run was made at CarBoy in Houston, TX. Ambient temp - 83deg F/85+% humidity.
 

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Whiteyfoo said:
I had a chance to put the Viggen on the dyno this past weekend. Unfortunatly I left the ODB reader at home so I couldn't record timing and boost data. This will serve as a baseline as I start doing power mods.
200K JPG -
http://abecovello.com/images/turbotaxi.jpg

I'm happy with the numbers, although the A/F curve has me a bit worried, but it wasn't pinging at any time, so I guess its not too bad.

Dyno run was made at CarBoy in Houston, TX. Ambient temp - 83deg F/85+% humidity.
Whats the worry with the A/F?
The slow drop to 12 may be due to the fast dyno sweep? Did you do more than one run?
 

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Looks pretty much just like the Dynosheet from my Viggen. The big difference being the A/F ratio. I think that might be down to different readings from different WB/O2 sensors on different dynos. The power results are strikingly similar despite the different A/F ratios.

Good results though. :)
 

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That A/F should be somewhere up around 14 on a normal run or so. The dip to 12 is not that bad but you may want to do the dyno again and get that ODB reader on there just to keep a better eye on it. What did your other pulls do on the A/F??
 

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stevehayes01 said:
That A/F should be somewhere up around 14 on a normal run or so.
WTF, 14?

You do that and you will have a lot of melted pistons in the engine:cheesy:
Close loop driving is an issue, you want to go stoich, but a turbo car under WOT is a whole different story you want to have the engine on the rich side <<13
 

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Discussion Starter · #6 ·
I did 3 runs. ALl of them came out pretty similar to one another. As long as everyone else thinks that A/F is normal, I'm ok with it. The car has never knocked or pinged, and it runs fine. I was just a bit worried that it was running a bit lean towards the upper range of the tach.
And once my Konis and rear strut brace get here from MP*, it will be time to start the power mods.



*Someday......:roll:
 

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14:1 is definitly not good for the motor long term, 13:1 is good, and definitly not 15:1 under boost.

Ultimate power for a turbo application is a high 12:1 like 12.8:1 for instance, higher and you lose power, gain heat, depending on the head and pistons you might develop heat spots and such... although saab heads in general flow well so 14:1 isnt going to kill your motor but long term.... i dont know if thats good. Im actually a little suprised you havent found overheating issues with such high AFRs (im guessing you havent because you havent mentioned it yet)

lower then mid 12:1s and you start to lose power due to too much fuel.

I would raise fuel pressure just slightly to compensate down low a little at least, some people crush their FPR, or you can usualy get replacement that isnt more then .5 more then yours, i dont know what FPR your using stock or otherwise...

Other then that those are nice numbers :) Your probably getting close to as much as anyone can under stock managment at top end with the same mods, pretty decent :)
 

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you can even see where your bad AFR is detering your power output:


see the lump and dip @3300rpm? then all the way up to about 4000rpm the power is going up but its rising, differently then 4000+rpm? At 4000rpm the powerband is fuller and rising at basically the same rate.

if your AFR was better down low you`d have a slightly better powerband,with the difference probably being the largest between 3300-4000rpm, my guess about 190whp instead of 177whp.

The only other thing i would change about this setup would be add some timing at 4500rpm to promote some more top end, that turbo falls very flat at that point.
Chip tuners can usual do things like i just mentioned, im not 100% sure on your situation but if that were my dyno sheet and it was in my old car thats what i would have concluded from it.
 

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TurboRush91 said:
Nice numbers.. my Viggen is still a freak I guess.... Can't wait to see post power adder dyno's..


232whp/293wtq
Your Viggen is also the only one run on a Dyno-mite dynamometer. Mine ran 213 whp on a dynojet, and would run 185 on a dyno-dynamics.

I still say you log your air-mass values and timing values. Unless the mechanical parts of your car were very modified, you'd need to be running different timing, airflow, and A/F numbers to get more power.

Obviously power doesn't just mysteriously come from nowhere. ;)

-Adrian
 

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adrian he has laid those numbers down on other dynos too. my vig put down only 193 hp and 244 tq on the same dyno same day. somethin was funky then.
 

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Adrian W said:
Your Viggen is also the only one run on a Dyno-mite dynamometer. Mine ran 213 whp on a dynojet, and would run 185 on a dyno-dynamics.

I still say you log your air-mass values and timing values. Unless the mechanical parts of your car were very modified, you'd need to be running different timing, airflow, and A/F numbers to get more power.

Obviously power doesn't just mysteriously come from nowhere. ;)

-Adrian
I said it before, I'll say it again.. the car laid down 231whp 1 year earlier on a seperate dyno in a seperate state in the spring... The first time around I thought fluke/dyno. It laid down within 2whp on 3 back to back runs..
ask Stromer, I wouldn't tell him what I had put down before because i figure it would be way off from what I did the first time because it was a fluke... then I put down 232whp+/- 1whp on 2 back to back runs with this dyno.. basically I'll strap the car down to the dyno and pull the number for anybody since I did it a year apart, several states apart, on different dyno's and put similar numbers down over a total of 5 pulls.
 

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I have talked to 2 seperate tuner companies and both have given me numbers between 13 and 14 as proper A/F under boost but hey I am definatley not the expert so I will bow to all your opinions and answers on that as well.


As for putting down more power than others your 232HP is not all that shocking of a number to pull to me since i know the T7 is much more capable than people give it credit. If you look at Ricot's 9-3 SE HOT with bolt ons he pulled 219WHP and 221WHP I believe on his stock software so it is definatley possible. My SE HOT estimated at 218WHP with a digimoto rolling road pull too so now I need to get it on the dyno again and back the numbers up.

Still great pull!
 

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stevehayes01 said:
I have talked to 2 seperate tuner companies and both have given me numbers between 13 and 14 as proper A/F under boost but hey I am definatley not the expert so I will bow to all your opinions and answers on that as well.

Still great pull!
odd because currently most all motor cars run in the 14.5:1 range and everyone knows that a forced induction car should run a little richer. Perhaps on these motors 14:1 isnt going to do much of anything , as long as its not going any leaner i suppose it doesnt have to be changed :)
 

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Running the stock turbo near max and "lean" A/F will give you EGT's 1000+Deg C after few seconds... no guestion about it.

For comparison, here are some old dyno prints from my viggen for you to see how little A/F does affect the power curve.
Solid line represents a pull where A/F was "lean" >13
http://viggen93.mine.nu/kuva/ennen_jalkeen.jpg
sama mods same day with a "fat" A/F (only torque curve...)
http://viggen93.mine.nu/kuva/vaanto_ahto_seos.jpg
A/F can be converted with this
http://viggen93.mine.nu/dyno/lambda.jpg
(A/F drops to 10.3 in mid range and raises to 11.5 in higher rpm range)
Next A/F adjusted to ~12.5
http://viggen93.mine.nu/cooleri/jalkeen.jpg

Peak numbers for these runs
Lean 293.6Ps and 495.5Nm
Rich 286.9Ps and 503.3
"optimal" 289.4Ps and 510.6Nm

So deviation in peak hp ~7 and torque 15Nm
All runs where made during the same day...
 

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very very nice, those were similar numbers to what i found while tuning my old car. Simply put mid-high 12:1 AFR is what is optimal, anything over is too hot.

i`d have to revert to what i originally said, 14:1,15:1 is just plain too hot, you`ll develop problems with the car in some time, might not be next month but it will eventually catch up to you.
 

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steve is right, anything is possible, my car has been runnin ****ty lately, and i haven't spent any time on it since i bought another vehicle to occupy my time as well, i dynoed like 200whp up in VT just to show u how ****ty this thing really is running, plus i have heavy heavy wheels on the car as well so thats not helping.;oops:

your A/F ratio is fine where its at, if it got any leaner i would be worried
 

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TurboRush91 said:
. ask Stromer, I wouldn't tell him what I had put down before because i figure it would be way off from what I did the first time because it was a fluke...
that is true.
 
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