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After 3 years, I am heading to the dyno on the 5th


mr jdm

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The journey is almost over for me, minus a few very very minor details. I am scheduled to go to the dyno on the 5th next month, where I hope to make my 500whp goal on pump gas. I would really like to hit 500 on 22 psi, but I might consider running as much as 24 on pump. I will post up a video and dyno results shortly. I really hope the motor holds it together. The car is fully gutted with aluminum dash and a fuel cell in the back. There is no a/c, heat, or power steering. Even been thinking about going with an electric water pump lately. The ultimate goal for the car wasn't so much the 500whp dyno, but running a 10.9 or faster on the strip. Of course on slicks and with a 2 step.

 

Sr20det

Stock bottom end

Arp Head Studs

Cometic Head Gasket

BC Valves, Springs, retainers

Tomei 272 12.5mm lift cams

Peakboost Exhaust Manifold

SC6176 .82 turbine housing

3" Short exhaust

Ebay Intake manifold (I might build my own, I should have but I'll see how it holds up)

100mm throttle body w/ 3" intercooler piping around

72lb injectors

Aeromotive FPR (Pressure will probably be set closer to 4 bar than 3 bar)

Single external walbro, if theres an issue I have one more external I might setup

 

And we will be tuning on a Haltech e8, which has been nothing but easy to use.

 

IMAG0757.jpg?t=1303836297

Edited by mr jdm
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Just ran my friends rb powered s14 and the single walbro was leaning out on the top end at around 400-450whp... fuel pressure dropping to 30. I would highly suggest more fuel before you go and have to reschedule a session. What makes matters worst is tuning against pressure drop and realizing it later and having a useless fuel map which is overly rich once the fuel pressure problem gets sorted.

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:o

 

 

Is there a particular reason you chose that location for the bov? I've heard that the closer to the gate the better. Plus it might be opening too soon before the cooler because the pressure probably drops 1-2 by the time it gets to the end of the line, or did you compensate for that?

 

I picked the spot on the intercooler because I wanted to keep my intercooler pipes clean looking. What exactly do you mean by the gate? The throttle plate or the wastegate, whatever you heard, from whoever sounded like they were talking to much and lack actual experience. It wouldn't matter where you kill the pressure in the system, it only gets killed for a split second.

 

Just ran my friends rb powered s14 and the single walbro was leaning out on the top end at around 400-450whp... fuel pressure dropping to 30. I would highly suggest more fuel before you go and have to reschedule a session. What makes matters worst is tuning against pressure drop and realizing it later and having a useless fuel map which is overly rich once the fuel pressure problem gets sorted.

 

 

God dammit man, whyd you have to go and tell me that. I guess Ill be throwing that second walbro inline before the 5th...

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I HIGHLY recommend the 2nd pump.. I'm running a Aeromotive 700 and I still had fuel issues.. I have a very similar setup to yours.. but .78trim twinscroll manifold.. I was able to hit 432hp without messing with timing too much (because I still wanted to break in the motor).. 500 is definitely possible. My tuner said when my motor was broken in I could make 550 easy at 24psi..

 

Good luck! And I hope you decide to run the dual walboros.. you'll lean out for sure on just one pump.

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Tomorrow if the day. tonight I'm going to go over a few things on the car. I will not be installing a second walbro before tomorrow. I am going to keep an eyeo n the fuel pressure gauge and hope it holds. I coudn't get a billet Y block to run the lines in time. Also, I talked to a few high horsepower evo's and they were doing alright with 500awp with a single walbro in tank. Hopevertyhing works out, if she blows she will be in the garage until next year.

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The car peaked at 430whp at 18psi at a 7k rpm redline.

 

My boost controller was not working, no matter what we did it did not respond. Knowing I would have to come back, I left it at that. The plan was to leave and come back later, run 22-24 psi and set the redline at 7800 rpm.

 

On the second session I was sure I would clear 470-480 whp and be extremely happy.

 

After the dyno, I went home and rescheduled my second session for 4 weeks later, so I would have some time to work out a few minor kinks and find a decent boost controller.

 

Driving home, I kept it under 3,500 RPM light load, it would only be MY luck that something bad happens. On the drive home my motor INSTANTLY shut down, almost as if the CAS, Ignitor, or Timing Chain snapped. I mean instantly. The car will still crank, not even a SIGN of it trying to fire back up. I was extremely tired, I did check though my injectors and coils have 12 volts. Tomorrow I will I will start the diasnostic. First seeing if the CAS is ok by visually seeing the injectors spray and spark firing with a coil removed.

 

If the CAS is ok, that only leaves the Ignitor if there is no spark. Il do a compression test also, I think the motor threw a rocker arm, but I am just shocked. 30 + HARD pulls on the dyno, not a single problem. Driving home under 3,500 rpm and the problem arises. I am beyond frustrated and exhausted.

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From your 430 hp at 18 psi result, it should make the following:

 

456 hp at 20 psi

483 hp at 22 psi

509 hp at 24 psi.

 

I dont know how you got this, but I would be more than happy to be in the 480whp range, let alone if it clears 500whp which was my original goal.

 

but right now, my car has 0 HP, from 430whp in one day to 0 an hour later.

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just curious.. how were you able to conclude those numbers? Maybe I can learn something new?

 

 

Just simple boost math. Use the pressure ratio as the hp multiplier.

 

for example, if an engine makes 200 hp with no boost then add 14.7 psi of boost and it should double the power (400hp). pressure ratio is 2 with 14.7 psi of boost. (2 x 200 =400)

 

so with 18 psi of boost, the pressure ratio is (14.7 + 18)/14.7= 2.224. that means 430hp could only be made if the engine could make 193.3hp with no boost. (193.3 x 2.224 = 430).

 

so, with 20, 22, and 24 psi of boost, the pressure ratio is 2.360, 2.497, 2.633. Which makes 456hp, 482hp, and 509hp.

 

works to estimate lower boost numbers also, for example 7.5 psi would make 290hp (1.5 x 193.9) in this case.

Edited by Pyro
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Just simple boost math. Use the pressure ratio as the hp multiplier.

 

for example, if an engine makes 200 hp with no boost then add 14.7 psi of boost and it should double the power (400hp). pressure ratio is 2 with 14.7 psi of boost. (2 x 200 =400)

 

so with 18 psi of boost, the pressure ratio is (14.7 + 18)/14.7= 2.224. that means 430hp could only be made if the engine could make 193.3hp with no boost. (193.3 x 2.224 = 430).

 

so, with 20, 22, and 24 psi of boost, the pressure ratio is 2.360, 2.497, 2.633. Which makes 456hp, 482hp, and 509hp.

 

works to estimate lower boost numbers also, for example 7.5 psi would make 290hp (1.5 x 193.9) in this case.

 

 

that still doesn't make 100% sense to me.. what about things like timing and fuel duty on higher boost.. I have my numbers for 10, 15 and 20 PSI.. I'll see if this equation works for me. nice to have a good approximate though..

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Well, it is just a simple method for estimating hp from boost, so don't expect too much.

 

it is just max theoretical power from boost, which can easily be reduced by tune, fuel, and environmental conditions.

 

however, it works much better than guessing 15 hp per 1 psi of boost, or something like that.

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