Intake, HS headers, and exhaust. Got G-tech, does this HP sound right?

[apzak]

Hey,I have hotshot headers installed, 2.25 inch exhaust, and injen ram air installed on my car. G-tech finally came in the other day (crappy condition, I was ripped off on ebay) and i taped it on my window because not even the suction cup works. Anyways, I redlined up to 2nd gear because the road I was on wasn't that big and G-tech gives me 143hp. Does that sound right for RWHP with those modifications? I searched and someone said a magazine gave the 240sx 18% drivetrain loss, then technoman said we are looking at about 22% drivetrain loss.

I'm estimating 170 crank horsepower, sound right or is my math off? Still have cold air to install... I'll see how much hp that adds once the rain stops. (4th week in a row) It's been flooring real bad here lately, but my new tires are real good resisting hydroflating.

And if your wondering, the roads dried up for a little when I used the G-tech. Then it started raining so I didn't get to check my 0-60. Maybe tonight when the roads are deserted.

[240SXedUp]

Crank and RWHP are different

[apzak]

yes I know, I would like to know my crank hp. And whats the difference with each gear? is my hp higher in others gears? I only got it up to 2nd.what gear do auto manufatures use when advertising? I would like to compare my current hp to the factory rated 155hp. How much did I gain?

[ITA240SX]

If I could suggest - if you really want to know how much power your 240 is making pay the $75 and have it put on a real dyno. You might be dissapointed. The G-tech is like any other computer, the output is only as good as the input (if even that in the case of this particular toy). At best you're going to get ballpark figures, and at worst you'll get wildly inaccurate crap.

Do you really think you got 15 hp just from bolting on a set of headers and catback? And for that matter, do you really think your 240 was making 155 hp before you started. How many miles does your engine have on it? Factory hp ratings are based on new engines, properly tuned, under strictly controlled conditions. If you're serious about find out your hp, there's really only one way to go.

Have fun Earl

[:: orion ::]

A stock '98 will put down around 125-130rwhp, more than likely right at 130. Add Injen = ~4-5rwhp. Add HS headers = ~5-6rwhp. Add 2.25" exhaust = ~7-8rwhp. So 143rwhp seems about right...

But ITA240SX is right - Dyno is the only way. But I'd bet that it's with +/- 3rwhp of 143...

So assuming 18% loss - - - 143/.82 = 174 crank HP.

Seems very reasonable, and is in line with the dyno #s I have seen in the past for S14s...

ALSO: To answer your question about manufacturers HP claim - They don't dyno the car on a chassis dyno and assume a drivetrain loss - If they claim 155hp, it's been measured at the crank, with the motor out of the car as they developed it. And as I said, most S14s will make 125-130rwhp stock, which calculates to about 17% drivetrain loss.

Check out the Sport Compact Car dyno charts on my web page to see the approx. gains they got on their Project 240SX, a '97.

http://www.cautioncreativity.c...s.htm

Later - Brian

[apzak]

I bought the car with 39,000 miles in november. Now it has about 48,000. How much would a 98 240sx weight with half a tank of fuel? I weight 150lbs. I think I entered 2850 in the g tech or 2950 I dont remember. I could always check again..

[jam149]

Nissan's claimed weight is 2859. Add some pounds for sunroof if you have one.

Best to go to a scrap yard and get the actual weight with you in the car. (or I've heard you can try the truck stop weight stations too!)

joe

[Dattebayo]

Yeah it all sounds right to me, but how do you get a $75 dyno test? You have to be getting some kind of crap dyno to be that cheap. The decent ones here are like $200 seiously.

[ITA240SX]

Yeah it all sounds right to me, but how do you get a $75 dyno test? You have to be getting some kind of crap dyno to be that cheap. The decent ones here are like $200 seiously.

You must live in CA, right? j/kThe places I know about use the Dynojet, and to be honest I have no idea whether it is a 'crap dyno' or not. Here are links to a couple of places here in VA I know of:

http://www.woodbridge-dynotech.com/

http://www.springfieldmotorsport.com/

http://www.abacusracing.com/index.html

Abacus Racing didn't list a price for the dyno time, but I thought it might still be an interesting link in that they advertise 275+hp KA engines, if anyone were interested in building a really fast N/A car.

Have funEarl

[apzak]

Well, I don't understand why the faster you go, the higher the horsepower is on the G-tech. Does that mean your getting closer to crank hp because less hp is being lost? Sorry the instruction manual doesn't describe this in detail. I just let my friend borrow the G-tech in his Twin Turbo Auto Supra and he got 340hp with G-tech. He's only got exhaust and magazines got 20hp with it. (I guess cause his engines bigger and turboed helping it breath gives more hp vs exhaust hp gains on the 240sx) Looks like he's getting crank hp, but now that I think of it the road was going uphill so that reading was crap. He told me he knows a place near Englishtown that does dyno readings for $20! I told him the G-tech probably wasn't lined up right and the road was going uphill so his reading is probably wrong. But his Supra IS fast, even if it's auto its sweet as hell and lacks the body roll my 240sx has:(

[:: orion ::]

I just let my friend borrow the G-tech in his Twin Turbo Auto Supra and he got 340hp with G-tech. He's only got exhaust and magazines got 20hp with it. (I guess cause his engines bigger and turboed helping it breath gives more hp vs exhaust hp gains on the 240sx)...

No, Supras just have that much power.

A friend in town with FMIC, boost controller, DP, and exhaust is making 403rwhp on the stock twin turbos. That's run-of-the-mill power for a BPU Supra...

Granted, it's a 6-speed, but still illustrates my point...

Later - Brian

[apzak]

stock supras have 320hp... at the CRANK

340hp with gtech is rwhp. He was going uphill so the reading is wrong, i'm just wondering why hp went up as his gear went up. Is my reading in 2nd gear accurate? or should I go up to 3rd, 4th?

[Evil98Silvia]

Yeah it all sounds right to me, but how do you get a $75 dyno test? You have to be getting some kind of crap dyno to be that cheap. The decent ones here are like $200 seiously.

You must live in CA, right? j/kThe places I know about use the Dynojet, and to be honest I have no idea whether it is a 'crap dyno' or not. Here are links to a couple of places here in VA I know of:

http://www.woodbridge-dynotech.com/

http://www.springfieldmotorsport.com/

http://www.abacusracing.com/index.html

Abacus Racing didn't list a price for the dyno time, but I thought it might still be an interesting link in that they advertise 275+hp KA engines, if anyone were interested in building a really fast N/A car.

Have funEarl

WHOA you live right near me. Im in woodbridge all the time. And I live in kingstowne/springfield/alexandria. Where at do you live?

Robbie

[Altiman94]

Gtech's are never right, they are based on calculations, so who knows what your actual numbers are.