down on power, can't figure it out...

[alkemyst]

98 SE, 116k miles.

Compression is good and even, replaced my fuel injectors, filter, i have header, 3" cat, 5Zigen 80mm ProRacer exhaust, Injen intake, cleaned my MAF, new O2's, new plugs and wires, new knock sensor.

Car makes only 109-120RWHP on the dyno.

Any ideas where else too look, could the PCV cause this? It's the only thing I haven't tried.

[cobras89]

that sounds about right for a KA24de especially with 116k.

[KaminaSan]

I was about to ask how that was "low" on power. 120whp sounds about right? 145 is the normal "ideal" rating right?

[Sterlz]

if it feels sluggish it could be your distributor. that exhaust might be a little large in diameter but that shouldnt make such a feeling of loss.

[alkemyst]

I have played with distributor timing. That is the difference between the 108 and 119WHP +2 degs more.

http://driftkat.com/images/Dyno20080712.jpg

[KiLLeR2001]

For the KA24DE.. 155HP at the crank I believe, so 120HP seems about right at the wheels.

[alkemyst]

For the KA24DE.. 155HP at the crank I believe, so 120HP seems about right at the wheels.

I am not stock.

[Moncef]

You are also on a Mustang dyno which is known to read lower than other dynos (Dynojet, Dyno Dynamics, etc)

[KiLLeR2001]

I am not stock.

The mods you listed aren't going to give you any substantial HP gain... What type of numbers were you expecting to see? If anything that 3" exhaust is probably not efficient with how much output you are putting out.

[mxexux]

I don't know what you are expecting...With intake, headers, and exhaust the power difference will be pretty minimal especially without a tune. The high mileage also doesn't help you. Besides, I think nissan rated the KA under really good conditions at 170hp. To the wheels that means 21% less or 134whp. 116K on the odo and the several possible conditions that affect power output can EASILY knock off 15hp from your dyno pull even with your bolt-ons.

[alkemyst]

With good compression the age of the engine shouldn't really matter.

the exhaust has been shown to give 15WHP...a tune may be what I need. When they dynoed the exhaust they didn't do a tune though.

[mxexux]

That 15WHP is probably what the vendor told you... That exhaust is designed for a turbo car. 15WHP can be gained from a turbo car with exhaust.

I highly recommend a tune. You can definitely get at least 20 more hp from a tune with stock parts even.

[Moncef]

Your AFR peaks at 15.6 at WOT. WTF!? The average AFR is shown at 13.5.

You need a tune...bolt on breathing mods do different things to different cars, so it's hard to predict the power gains. Straighten your AFR out and you'll see proper numbers. Start with an AFR of 12.9-13.0 and go richer/leaner depending on how the dyno #s change. An SAFC2 will be enough to control this. <hit me up if you want/need one>

[alkemyst]

That 15WHP is probably what the vendor told you... That exhaust is designed for a turbo car. 15WHP can be gained from a turbo car with exhaust.

I highly recommend a tune. You can definitely get at least 20 more hp from a tune with stock parts even.

no it's not...I swear it's like all the old 240SX knowledge was lost in the black ages.

Alex Chang one of the moderators on Fresh Alloy had tested his car on a dyno and picked that up.

What's the best 'tune' out there? AFAIK the stock ecu is not programable.

[Enna]

That's why you use a piggy back, SAFC II for instance, to alter that inputs that the ecu reads. Sounds like you just need to do that and you'll be where you expected to be.

[codyace]

I'll agree with the OP that a 3" exhaust will most certainly gain power on a KA, 15 whp may be a bit egregious of a claim, but combined with a header and high flow cat I could see 15 total gain from it.

Figure that mustang dyno may read a little low, you're looking at roughly 130ish maybe on a dyno jet. That's decent IMO for a bolt on car and nothing substantial like cams, a tune, or intake manifold.

Your AFR peaks at 15.6 at WOT. WTF!?

Um, you need to learn how to read that dynograph.

Look over it again. It shows min/max/average. That doesn't translate to at WOT or anything. That 15.6 is from the very start of the graph. The average is 13.5. It seems to be up around 14ish in the middle, but that's not gonna hurt anything there, especially N/A. Looks to be a nice 13.5 at WOT

[alkemyst]

cody would you see any advantage in a SFAC or something else now?

I am going LS1/2 over the next year. Almost down to 0 credit owed (from college and buying a house)...once that's gone it's all bank for my swap.

It will probably be 12-18 months before the swap is in and done though....

[codyace]

To myself (and many) an safc is an evil little box...granted some HP can be potentially found, it's certainly of voodoo type...I don't like misinterpreeting a MAF signal ya know?

Good to hear on the V8 :D It's a shame the market for SR stuff is gone, as I'd sell mine in a heart beat hehe.

[orion::S14]

That 15WHP is probably what the vendor told you... That exhaust is designed for a turbo car. 15WHP can be gained from a turbo car with exhaust...

As it's been pointed out already...there have been consistent dynos showing 10-16rwhp gains with nothing more than a 3" exhaust on a KA.

Stock Dyno (on a dynojet):

http://www.ka24development.com/file_images/240sx_dyno_chart.jpg

Look at this one, same car...the "stock exhaust manifold" (blue) dyno was with nothing other than a Apexi N1 exhaust:

http://www.ka24development.com/file_images/240sx_dyno_hotshot.jpg


Sorry, we're drifting a little off topic here with this...

...

BUT...I'd expect +135rwhp on a dynojet out of your car, 'alkemyst'...on a Mustang dyno...I dunno.

- Brian

[codyace]

Nice posts Brian!

Having dynoed hundreds of cars myself, across the board I can say that all cars gain power from a 3" exhaust...turbo and or N/A. We also always suggest cutouts for those not wanting a big pipe and the possible resonance from it...

[alkemyst]

BUT...I'd expect +135rwhp on a dynojet out of your car, 'alkemyst'...on a Mustang dyno...I dunno.

- Brian

Same here, I was figuring around 140ish.

I have no idea why I am flat. I guess I could just have a weak engine.

I am assuming a stock KA makes about 115-120HP on the same dyno.

[KiLLeR2001]

Same here, I was figuring around 140ish.

I have no idea why I am flat. I guess I could just have a weak engine.

I am assuming a stock KA makes about 115-120HP on the same dyno.

The answer to your question has already been provided to you. You need a tune.

[alkemyst]

The answer to your question has already been provided to you. You need a tune.

Is a tune going to help with good AFR?

I never played with SAFC type boxes. Would it be worth it for a 1-2 year life?

[240sxrb25]

Are you really going to buy a unit to tune a non turbo ka for a couple hp. Waaaaste dude. My ka car is using a who knows how old factory filter and air box and header cause I know that it's nod worth modifying for 9hp haha

[alkemyst]

it's like $300...if it would help me enjoy the car more over the next year or two...

We all understand all the beaters out there dude.