12.48 @ 110.7 for jdubya and his JHM B6 S4 with full exhaust and JHM N20

[Carlos_Audi_Tech]

I mentioned stock manifolds in regards to the nitrous cars becuase it makes a much bigger difference than the supercharged cars. While the decomposed nitrous has a higher content of 02, and therefore a lower combustion gas volume per specific output, it doesnt have the increased pressure differential the supercharged cars do. I could do some math to relate what boost level is necessary compared to what shot size to make the supercharged car work better with the stock manifolds but suffice to say without some static pressure to force the air out the sprayed cars are gonna choke off with stock manifolds. Iirc cabracco85s 12.0 run had a 116 trap on a 100 shot?

Im not going to pretend to be Tops at math. I can just relate for the hotrod stuff Ive been threw over the years. Maybe a little less complicated terms for me.

The N02 still needs to be pulled into the motor Via vac of the motor/pistons. This takes some of the positive effect of chemical enhancement out. N02 cars run with LOADS of Tq and a steady feed of HP. STill when you look at a power chart of a N02 car it stays within the curve (less the power initiation) of the motor.

If any of this babel makes sense it was meant to say on N02 motor mods are more usfull then on boosted cars due to the motor still is using its base component to bring in air/power. Also where a boosted car makes more power faster as the RPM’s go up. The N02 cars keep with the motor curve. So believe it or not. If done right N02 is safer for the motor then boost.

impressive results by the way.

[sakimano]

I mentioned stock manifolds in regards to the nitrous cars becuase it makes a much bigger difference than the supercharged cars. While the decomposed nitrous has a higher content of 02, and therefore a lower combustion gas volume per specific output, it doesnt have the increased pressure differential the supercharged cars do. I could do some math to relate what boost level is necessary compared to what shot size to make the supercharged car work better with the stock manifolds but suffice to say without some static pressure to force the air out the sprayed cars are gonna choke off with stock manifolds. Iirc cabracco85s 12.0 run had a 116 trap on a 100 shot?

great point…I’d never have thought about that.

[beemercer]

I mentioned stock manifolds in regards to the nitrous cars becuase it makes a much bigger difference than the supercharged cars. While the decomposed nitrous has a higher content of 02, and therefore a lower combustion gas volume per specific output, it doesnt have the increased pressure differential the supercharged cars do. I could do some math to relate what boost level is necessary compared to what shot size to make the supercharged car work better with the stock manifolds but suffice to say without some static pressure to force the air out the sprayed cars are gonna choke off with stock manifolds. Iirc cabracco85s 12.0 run had a 116 trap on a 100 shot?

If any of this babel makes sense it was meant to say on N02 motor mods are more usfull then on boosted cars due to the motor still is using its base component to bring in air/power.

x2, this was I was describing from the theoretical side. The motor is still normally aspirated, nothing is forcing it in. Iirc when designing headers for nitrous cars you are supposed to compensate pretty significantly as the shot gets bigger.

[jdubya]

Thanks for posting Saki! That was the first run of the day before the clutch let go. Slipped on that run in every gear. My second try went right to red line in 2nd so I let out and parked it. Spoke with Andy @ SB and he said it was because I put too much heat in it. Me and a few others agree that’s total BS. Looks like I’ll need to step up to a JHM clutch.

[sakimano]

hey jdubya…great run and welcome to AR. Great way to make a splash lol

That sucks about the clutch. Sorry to hear it. What is your launching technique?

[jdubya]

I try to launch around 3000-3200. That seems to be where I cut the best 60. I imagine with a better clutch I could do a little better.

I had a 600WHP Terminator Cobra before the S4 and I couldn’t get a good launch to save my life. Much easier with AWD. ;D

[RodV8]

Welcome to AR jdubya!

X2 on the clutch, should help out with keeping that monster power to the wheels.

[sakimano]

is the southbend setup equipped with a LWFW similar (in weight) to the JHM LWFW?

[jdubya]

Yes. It’s a steel one piece unit. Not quite as light at the JHM setup.

[sakimano]

Jhm lwfw is 13 lbs I think (stock is 26)

[B6JoeS4]

I love my LWFW. Completely changed high rpm shifting.

[sakimano]

I love my LWFW. Completely changed high rpm shifting.

expand on that?

[beemercer]

I love my LWFW. Completely changed high rpm shifting.

expand on that?

I think its only the case (lwfw chaning high rpm shifting) when you have a JHM short shifter, all those stock shifter preffered goofs will just miss out… haha

[sakimano]

[quote=“beemercer,post:22,topic:2859”]
stock shifter works just fine!

http://i375.photobucket.com/albums/oo193/sakimano/IMG_0025.jpg

It’s not like I ran 13.6 or something…

[beemercer]

haha shouldnt that be thank you for jumping on board and being one of the first 05s to get a tune (I believe only Jay’s car was tuned before)? Original tune revision with check engine light, milltek catback, probably 30whp down from where it should have been. 90* day with low air pressure and 400 cars at the track. No 94 octane either, full weight and then some. No launch control.

[cabracco85]

I mentioned stock manifolds in regards to the nitrous cars becuase it makes a much bigger difference than the supercharged cars. While the decomposed nitrous has a higher content of 02, and therefore a lower combustion gas volume per specific output, it doesnt have the increased pressure differential the supercharged cars do. I could do some math to relate what boost level is necessary compared to what shot size to make the supercharged car work better with the stock manifolds but suffice to say without some static pressure to force the air out the sprayed cars are gonna choke off with stock manifolds. Iirc cabracco85s 12.0 run had a 116 trap on a 100 shot?

Congrats to jdubya on the 12.4

My car was not on the 100 shot when i went 12.0 it was the jetting for the 70 shot as i dropped the other jets i had. Which was for a 85 and 100 shot. Its been awhile since ive been to the track with my s4. Id have to pull the jets to see which ones are in there now. If they are the 85 then that was what i was running when i went 12.0. I dont remember off the top of my head which jets i dropped and lost. I do think i was at the limit for the stock down pipes which was around a 12.5@110ish which is about the same as the stock s/c auto went. As far as i now me and the auto cars were the only ones that has maxed out the flow for the stock dps. As for the stock manifolds we will see what times i can get out of it. I think there is a 11.7 in my car the way it sits.

[sakimano]

As for the stock manifolds we will see what times i can get out of it. I think there is a 11.7 in my car the way it sits.

Would be great if you could get to the track a couple of times in the next month…would love to see you battle D for the fastest title

[SpeedETC]

Jdubya, welcome and congrats on the run!! Next time I am in OH, we will catch up.

[B6JoeS4]

Well it looks like Jdubya is dumping his S4. He said he is getting something with more potential

[sakimano]

damn, that’s disappointing. Hopefully something AR related. Good guy.