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-   -   Decent Hp? (https://www.nopistons.com/2nd-generation-specific-17/decent-hp-49511/)

merzzzy 06-07-2005 04:11 PM

Well my cars broken in good so I decided too dyno it and see how much power its making. Now im not sure if I should be happy, disapointed or just in between.



Mods:

-Rebuilt s4 6 port motor

-large street port

-removed air pump

-removed 5th/6th port actuators

-hks intake

-pacesetter headers

-custom single exhaust 2 1/2 inch pipe

-walbro fuel pump



I only got one run as it was kinda a favor because they didnt have alot of time but I have 150.6hp to the wheels and torque is messed up for some reason.



Let me know how that sounds.

mazdaspeed7 06-07-2005 06:30 PM

The walbro is hurting power. N/a's run too rich to begin with, and walbro's only make it worse by overwhelming the stock FPR and raising the fuel pressure.



You hp number is low, most likely due to the above reason. Put the stock pump back on.

One320B 06-07-2005 09:17 PM

Yea...could be fuel related; a streetport really doesn't need all that much fuel over the stock port..at least on an NA.. get a wideband, check the AFR, or go back to the dyno and see if they can give you an AFR readout..that way you'll see what your running and can adjust for it by putting the stock pump back on..or maybe an S-AFC if you plan to throw NOS or FI at it...

neevosh 06-08-2005 02:26 AM

I've seen 150 RWHP on stock port engines and full exhaust and intake, and around 180 RWHP on a streetport.

DareBee 06-08-2005 07:39 AM

A friend of mine pulled 174 rwhp on a street port S4.

Aux ports where converted to an S5 style actuation.

S5 VDI manifold

Apexi SAFC2

Header + high flow exhaust

K&N

He believes there is still more to be had by better SAFC tuning yet.

mazdaspeed7 06-08-2005 09:20 AM

Kahren did 165 wheel hp on stock ports with the stock ecu/intake manifold on a S5. Haltech and custom intake manifold put him at 180 wheel hp on the same engine. On another car he made 195 wheel hp from a streetported S5 engine in a S4 with the stock ecu and S-afc.

ROTARYROCKET7 06-08-2005 09:23 AM

my car is pretty much stock. What would the s-afc do for me

C. Ludwig 06-08-2005 11:05 AM

I've made 166 on a stock port/stock electronics engine. Fuel and timing tuning only. As has been said these engines run grossly rich with a completely stock setup. We ended up dialing fuel pressure back to around 25psi (end of regualtors adjustment) to bring A/F ratios into the 12.5:1 range. We've worked on some stuff to pull more fuel out and will dyno again. Expect power to fall somewhere north of 170whp with correct fuel tuning. Our exhaust is also not quite optimized. Hopefully there is another 5hp there but I won't hold my breath.



FWIW an SCCA ITS engine (the engine I'm referring to) is box stock from the AFM to the exhaust ports. The six-port sleeves are commonly removed as are ours. Speedsource claims 175whp from there package on stock electronics. And that number is well varified by many racers. With their Motec package they claim 185whp.



We found added timing to be a major source of HP. We started at stock and gradually bumped timing up until we found best power from 25* BTDC under full load at 7000rpm. We gained about 10hp for every 5* we advanced the timing until we hit 25* BTDC at which point the power didn't rise anymore.



Taking the above numbers into account a IMO a well built and tuned street ported motor should be capable of 200+whp.

merzzzy 06-08-2005 05:09 PM

so what are all of you saying? is my car out of tune by alot or could they have been wrong at the place I went?



Should I get a SAFC of will that help me with all the issues?

drftk1d 06-08-2005 05:19 PM

[quote name='ROTARYROCKET7' date='Jun 8 2005, 09:23 AM']my car is pretty much stock. What would the s-afc do for me

[snapback]722623[/snapback]

[/quote]



better fuel economy


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