Just out of curiosity what is a guess at the crank hp. Mods are, 181 pulley, Jerry's tune from LET, SL55 intake, modified grill for cooling/air flow(waldig), phenolic spacers, LET cooling mods HE/CM30 pump.
My guess would be about 400-420@ the crank. Anyone else

 

Good as of guess as any.
I guess it's time to go to the dyno!

 

Good guess!! I would say that is an accurate number. I am right around the 400-405 mark with my mods so.......You should see a little more in theory with your larger pulley, but we all know that debate. Haha.

 

I know this is not an apples to apples comparison, but here's what I figure for mine:

Stock: 350 hp
NeedsWings CAI: +25 hp
Code3 SC Pulley: +30 hp
Total: 405 hp at the crank. This is supported by my track times, as it would take just over 400 crank hp to push the car down the quarter mile in 12.8 seconds.

I'm sure yours is doing better than mine, since you've got the larger crank pulley. Also you've got an ECU tune. Is that a custom tune, or an out of the box tune? If it's custom, I've heard guys gu-estimate an added 20 hp for the tune.

I wouldn't be surprised if you were pushing 430 hp at the crank.

Take it to the drag strip and see what it'll run. That's a better indicator of hp than any guess work we can do here.

 

Depends on the Chassis Dyno used and the math you use for conversion to crank HP...

Here's a website a member posted that can be used to calculate crank HP if you use a Dyno-Dynamics or a DynoJet Chassis Dyno

http://www.to4r.com/calcs/pwtq.php

 

I have the 181mm pulley, SL55 intake and LET tune. My Dyno on a very warm day and car was about 315hp (I dont have it handy but I posted it here 4 or 5 weeks ago).
I have done 12.5 @113mph as my best so far. I am going back tonight to try with the fan plugged in(dumb story) and Klotz Octane boost added. The car seems to like the octane boost in the little driving I have done with it in. If I can hook up good I should be in the low 12 range.

MikeR

 

You should be 12.3's with your setup. My elevation is about 800' higher than MikeR and I ran 12.52 with no tune, 178mm asp pulley, and nw intake.

 

Probably an update for a different thread but.....
Tom, did you ever discover just what was pulling your times down a month or so ago?

 

I basically have the same set up as you. Other then SL55 vs NW. I put mine on a Dyno jet and was a 292 whp @ 95 degrees and 60 % humidity. This was before the NW.I will try to have a new dyno next week.

What was your temp and humidity? Jerry wants to redue the ECU. Thought I was running a bit rich. I will wait till December when he comes down my way.

 

I'll post over in that other thread, so as not to jack this one.

 

Nevermind. Edited to deleted bad math. :P

 

I have similar mods and did 320rwhp/323tq on a dynojet during a 90 degree day. According to the calculator BrianBrave posted that is 376rwhp/380tq at the crank. You can not just add the HP numbers that mods on their own created. Unfortunately you will never see the 26hp for the intake added to 40hp for the pulley and 20hp for the tune. You get a “blended” amount of these three mods working together that is much lower.

 

Usually that is very true. You can't just stack the numbers and get a total - like I did above. However, those are the numbers from having those items stacked in that order. By that I mean Rob @ NW dynoed his car stock and then with the CAI. He got an increase of ~25 whp. Then another person (I can't remember who - might have been SRT Dan) dynoed their car with the NW CAI, then again after adding the Code3 pulley. He got an increase of ~30 whp. So those numbers stack. As long as you work it that way, you can stack the numbers.

 

Correct, the net gain was 5 for the pulley instead of what they advertise as 20 or 30 for the pulley over stock. Same thing with the tune. it may be 20 over stock, but only net 7 with a CAI and a Pulley.

 

Actually, the total gain is often greater than the individual numbers combined (assuming you are using HONEST numbers). For instance: If you add a high flow exhasut to a car that is otherwise stock, you will not pick up as much power from the addition of the exhaust system as you would installing it on a car that already had a high flow intake and pullies to induct more air. The more air you're taking in, the more important it is to get exhaust out. This is why it is important to know if an aftermarket part was tested on a stock vehicle or an already modified vehicle, as performance parts will many times yield higher gains on a car that has complemetary mods.

 

The net may be greater but you will not see 330 stock, add an intake and add another 26 (356) then add a pulley 30 (386) and so on.

 

Uh... that's 350 stock, not 330.

And, yes, you can add an intake and get 25 more for 375. And yes, then you can add a pulley and get 30 more for 405.

 

I can tell this is going nowhere.....take your math to a dyno and be disappointed just like everyone else. I wish you were correct, cause we all would have 400 hp cars and to date no one has posted that number up with out a 150 shot of Nitrous.

 

Okay, I don't want to spoil anyone's expectations of mankind or ruin false hopes, but the reason this is not happening is because you are being misled by the numbers that the manufacturers are giving you. I'm sure some manufacturers go so far as to lie or cheat the numbers. However, I believe the major issue is due to the fact that after market companies almost always advertise "peak" HP & TQ gains and then we compare this to our car's "peak" power output. Depending on the parts you are installing, their peak gains many times do not coincide in the RPM range. A pulley might have gained you 25 HP, and an exhaust system might have given you 10 HP. But what a lot of people don't pay attention to is where you gained the power. Yes, when you added all the mods onto your car, you gained more power than you think. The reason you aren't seeing 35 more HP on the dyno is because they are giving you this extra HP at different areas in the power curve. Yes, they most likely still complimented each other, but you will feel the power of that pulley at a lower point in the RPM range (due to SC efficiency) than you will the exhaust system (which will assist more at the higher RPM). This is why you always hear people mention that important "power under the curve". If you pay close attention to that, you should find your missing HP. Some people feel that dyno numbers are pointless for the comparison of two cars. The only way to measure the real effectiveness of your mods is to hit the track. This is where the math makes sense.

 

B.T.W. I apologize for jacking this mother. I'm gonna shut up now.