WARNING!!! DANGER TO MANIFOLD!!! !@#$, 5-SFE DI Nitrous Build Thread - Dyno Charts Included!!! Options

[Neon90424]

What would fail first? melted pistons?

[94celicadude]

you are going to blow that engine, your peak torque is at 4000RPM, look at your AF ratios, you are in the 14s.

Thanks for the vote of confidence....

I do realize that the AFR is in the 14s as soon as the bottle hits, but to be comepletely honest it climbs out of the RPMs so quickly, I do not believe it to be causing harm at this point.

Now I am by no means a professional tuner, nor did I tune my own car, but I feel that the 5s is a solid motor that can take this abuse...not for ever of course.

Please correct me if I'm wrong, I dont want to sound ignorant by any means.

What do you think would fail first as Neon asked? I know for a fact the bottom end is strong enough, if you've ever cracked open a 5s you know that the rods are beefy as hell, I also had them shot peened to recondition and strenghthen them during my rebuild.

I appreciate all the advise I can get and I do listen to recommendations, but I would appreciate you not just getting on an saying that I'm going to blow my motor just because my AFR is in the 14s momentarily.

[evo_lucian]

Sorry I didn't read the entire thread, what size jets are you running ?

With nitrous oxide one should not rely heavily on wideband readings especially if you are using a fogger system. I highly recommend you learn to read spark plugs. Spark plugs never lie.

Secondly I suspect the lean afr your dyno graph is showing as soon as the nitrous is activated is probably a fuel pressure drop in the fuel rail when the fuel solenoid is energized. What fuel pump are you using.

Lastly I highly recommend you change the distribution blocks that came with your zex nitrous kit. The distribution on these are horrible. The bottom two ports get the majority of the nitrous distribution. These two ports are connected to cyl 1 & 4 so they will run leaner. You may say that your wideband is giving you a good reading so all is well, but unless you have wideband sensors just after each exhaust port then your wideband is getting a "combined" AFR for all 4 cyl . So cyl 1 & 4 may be seeing a 13:1 AFR and 2 & 3 may be seeing 10:1 so when these 4 reading combine in the exhaust manifold before the sensor , its none the wiser. This brings us back to my previous point, "learn to read spark plugs"

All in all , I like your build. Good luck.

[94celicadude]

I'm actually running a factory fuel pump for now.

I have a FP gauge on the car and I see 48 psi of fuel pressure while the nitrous is activated. The kit actually calls for 40 psi, so i know that I'm ok in that regard.

It is possible that the instantaneous lean spot is from the fuel pressure dropping in the fuel rail once the fuel solenoid kicks in, I do agree with you.

Now that i know I am making good HP numbers with the nitrous, I will do some test and read the plugs, I'm running NGK Platinum plugs, which I really like and have had no issue with.

I tried to source a set of those one step colder, and found it almost impossible and very expensive, around $50 for a set of 4

But I do like your input and suggestions, had not thought about the distribution blocks being biased in the...well distribution lol

What would you recommend I change the blocks out with? Brand? Style? Design?

Thanks again for the input! I will let you all know once I've had a chance to read the plugs and see what is going on, will even try to source a stethoscope camera to check my piston tops and see what type of carbon/heat patterns I have.

Cheers!

Sorry I didn't read the entire thread, what size jets are you running ?

With nitrous oxide one should not rely heavily on wideband readings especially if you are using a fogger system. I highly recommend you learn to read spark plugs. Spark plugs never lie.

Secondly I suspect the lean afr your dyno graph is showing as soon as the nitrous is activated is probably a fuel pressure drop in the fuel rail when the fuel solenoid is energized. What fuel pump are you using.

Lastly I highly recommend you change the distribution blocks that came with your zex nitrous kit. The distribution on these are horrible. The bottom two ports get the majority of the nitrous distribution. These two ports are connected to cyl 1 & 4 so they will run leaner. You may say that your wideband is giving you a good reading so all is well, but unless you have wideband sensors just after each exhaust port then your wideband is getting a "combined" AFR for all 4 cyl . So cyl 1 & 4 may be seeing a 13:1 AFR and 2 & 3 may be seeing 10:1 so when these 4 reading combine in the exhaust manifold before the sensor , its none the wiser. This brings us back to my previous point, "learn to read spark plugs"

All in all , I like your build. Good luck.

[KAOS]

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaand subscribed!

Awesome details! Keep up the great work!

[evo_lucian]

I'm actually running a factory fuel pump for now.

I have a FP gauge on the car and I see 48 psi of fuel pressure while the nitrous is activated. The kit actually calls for 40 psi, so i know that I'm ok in that regard.

It is possible that the instantaneous lean spot is from the fuel pressure dropping in the fuel rail once the fuel solenoid kicks in, I do agree with you.

Now that i know I am making good HP numbers with the nitrous, I will do some test and read the plugs, I'm running NGK Platinum plugs, which I really like and have had no issue with.

I tried to source a set of those one step colder, and found it almost impossible and very expensive, around $50 for a set of 4

But I do like your input and suggestions, had not thought about the distribution blocks being biased in the...well distribution lol

What would you recommend I change the blocks out with? Brand? Style? Design?

Thanks again for the input! I will let you all know once I've had a chance to read the plugs and see what is going on, will even try to source a stethoscope camera to check my piston tops and see what type of carbon/heat patterns I have.

Cheers!

http://www.dynotunenitrous.com/store/scrip...p?idproduct=185
"Showerhead" nitrous blocks

As a precautionary measure I would upgrade the fuel pump.

Copper plugs will be fine , 1 step colder.

[evo_lucian]

What jets were used to make the 196 whp ?

[94celicadude]

.54 in all the nitrous side of the nozzles, .19 in the fuel side of the nozzles.

The distribution blocks were jetted to .46 on the nitrous side and .16 on the fuel side if I remember correctly.

I am actually going to take her to the dyno again in the next few weeks to see if I can get the over 200 WHP numbers ive been looking for.

Will keep everyone posted!