kopbet89c4

Hmmm... After I build my bulletproof 383 /w upgraded drivetrain and spray a 200 shot on top of it, I expect high 10s. Maybe 200+ mph top speed if I can still retain a 3.07 rear gear and bump up the revs.

So next in the next year or two, its unofficially my domestic pushrod 383 cubic inch 4.030" bore x 3.750" stroke all American Iron block SBC torque expressive V8 here,

vs.

an import high output DOHC 3.0L 86mm x 86mm I-6 engine + turbo with an overengineered stock bottom end and /w the pinnacle of Japanese engineering and tuning.

Oh, and I happen to be Asian/Pacific Islander here sportin' a Vette, while he is all 100% American made handling a Supra. Talk about a change of heart with a touch of irony here

He tells me in a year or two, he'll build a single turbo conversion and APU+++++++ it and turn it into an 800 RWHP dyno/highway queen. Yeah, I know, he's got a fat wallet too, but unless he becomes man enough to spray, he can have all the rwhp he wants with a T88 turbo like he says, but still run 12s all day. He seems not to trust nitrous at all. Dunno why...

zelement

what kit is this? so you are direct port? and you push a button? how is your fogger plumbed into the runners?

zelement

xeugep, a lot of the stuff you are saying leads me to think that you don't have nitrous. How do you fill the bottle to 1300psi. You are talking about bottle pressure. you can fill the bottle completely full but still have 650 psi bottle pressure due to the temp. The only way to increase your bottle pressure is by heat.

ClarenceT

What's the difference between a 600hp supra and an 800hp supra? One runs a high 12, one runs a low 12

kopbet89c4

I don't have a bottle heater. I know the pressure is lower at lower temps, but also higher at warmer temps.

Mr Mojo

Since I'm on the road and can't take the time to read every reply, here's my take.\

First off your balding drag radials is exactly what you want. You'll have a bigger contact patch the balder they are(same goes for street tires) Bald tires only affect you in the rain.

Now, a stock Supra you may be able to handle if you can get him at the tree. I raced a modified Supra, I ran 13.00 to his 13.49, but I only hit 108 where he flew past me at 128. I took him on the tree everytime and he didn't pass me till just before the finish line.

Don't talk about street racing or racing from a roll, that isn't allowed here(and I've heard some poor excuses too).

Just take it to the track and kill him on the tree. Make him work for it, if he beats you on the line, don't even try.(tell him you stalled and then do a rerun )

HeeHaw89

Well aren't you glad you still don't have that silly Civic now? Your buddy would have to go find someone else to play with

rocco16

If the outcome could be accurately predicted, then you wouldn't need to race.

Git out there and run 'im!!! Wus!


PS A new Supra? I thought the last new Supra was made several years ago???

Larry
code5coupe

dizwiz24

If you keep adding nitrous to a bottle, yes its pressure will increase.

For one thing, the compression of a gas generates heat, so that raises the pressure.

2. Simple PV=nRT shows that as n (the number of moles nitrous you add) increases, so does the pressure. Now, going back to thermodynamics, PV = nRT is inaccurate under certain conditions. I cant remember which. Its principles dont change, it just becomes a poor predictor under certain circumstances.

One way to get as much nitrous as possible in the bottle is to keep cooling the bottle. Of course, if you put too much in when it warms back up...BAM! its pressure will go up and youd probably blow a rupture disk.


Someone asked about nitrous. My nitrous system is a 100 shot wet NX. On the dyno it boosts rwHP by 90 (430 at the wheels) and rwtq by 130 (480 at the wheels).

If you are considering one always run a wet system (sprays fuel with the nitrous). Dont do a dry system where you rely on a booster inline pump to overpressurize your injectors.

My system is rigged with the following safe guards. Fuel pressure safety switch (low fuel pressure it cuts out), window switch (set nitrous to only come on and go off at a certain rpm, mine is set at 3200 RPM on and 5800 RPM off), fuel pressure and nitrous pressure gauges. I also have lights hidden in the vent indicating to me that electricity was supplied to both solenoids.

Heres some tips on nitrous
1. A full bottle generates more HP than a half bottle even at the same pressure. This is very frustrating since you are always spraying the same amount of fuel. As an end result I top off my bottles when they are half empty. This fact about nitrous sucks.

2. Pressure. You must be at the optimum pressure. Pressure is directly proportional to temperature. If I get into my car after its been sitting at work in the summer, that nitrous system is ready to rumble. I merge into traffic at 120 MPH from the on -ramp.

However, if I come into the car when its been sitting in my cool garage, than I have to turn the bottle heater on (its got an insulating jacket aroudn it too-else you lose too much heat).

It can take up to 15 minutes for the bottle to get to the right pressure. So if I run into some punk in an 03 cobra in the first 15 minutes of my drive....im screwed. To counteract this, I run the heater constantly making sure its at the right temp in case I run into punks.

3. The factory fuel side jetting for NX systems is too rich. They do this for a safety factor. Go to a dyno and put one size smaller fuel jet in until your a/F ratio goes from too rich (mine was like 10.5:1 with NX specified fuel side jets) to a still nitrous safe 11.5-12.0:1

4. If you run more than 100 HP shot, upgrade your in tank fuel pump to a hot-wire Walbro unit. A few LT1 owners have damaged their motors the moment they went from 100 HP to 150 HP shots even though nitrous companies claim that a stock setup can run 150 shots.

5. Look at where your air inlet temp sensor is. I recommend mounting your N20 injection tube downstream on this (or at least relocating it) Do not spray nitrous directly onto this. If you do, the computer will sense very cold air and dump loads of fuel in.

Of course, if you dont have a wet system(not injecting fuel too), then this extra fuel the computer dumps in is necessary.

System costs about $1100 for everything I had.

Sorry for hijacking this thread.

Kick some supra butt

neat

This is incorrect. Nitrous has a stoichiometric ratio of about 6:1 when mixed with gasoline. The more nitrous you use, the richer you have to be to play it safe.

Example:

Car "A" makes 300 HP NA, and 400 HP on the juice. Of his total HP (400), 300 of that requires a Af ratio of 12.5-13.5:1. 25% of his HP needs a 6:1 AF ratio. So, (13+13+13+6) / 4 = proper AF ratio, or 11.25:1.

Car "B" makes 300 HP NA, and 600 HP on the juice. 50% of his total horsepower is needs a 6:1 AF ratio to remain safe. So, (13+6) / 2 = proper Af ratio, or in this case 9.5:1.

For those wondering how I came up with the math, here it is:

Figure the percentage of your total HP that comes from nitrous. We'll use a complicated one this time. Say a car makes 315 RWHP NA, and with a 125 shot should make 440 RWHP. So, 315/440 = .7159, or about 72%. 72% of the power is NA, that means that 28% of the total power is coming from nitrous. Use these 2 numbers as a fraction ( 28/72 ) and repeatedly reduce by a factor of 2 until one of the numbers is no longer divisible by 2. So 28/2 = 14, and 72\2 = 36. Our new fraction is 14/36. Reduce by 2 again, and we get 7/18. Or, 7 parts nitrous horsepower 18 parts NA horsepower. For every part of NA HP use the number 13 (this represents a 13:1 AF ratio), for every part N20 HP use the number 6 (which represents a 6:1 AF ratio). So, we need to add 13 together 18 times. 13 x 18 = 234. Now we need the nitrous part of the equation, which is 6 added 7 times. 6 x 7 = 42. Add 42 and 234, then divinde by total parts. 7 parts nitrous HP and 18 parts NA HP make a total of 25 parts, 234 + 42 / 25 = 11.04. That is the leanest you'll want to go while on the bottle.

My point is that once the shot is big enough, 11.5:1 or 12:1 AF ratio will cease to be safe.

FWIW, I think you'll smash him in a standing start 1/4 mile. Even from a roll on, with the juice you should stand a chance.

VR'92

Nice vid Kara!

red88L98convert

i wouldnt count on the 1/8 mile to be a big benefit. bad turbo lag is almost a myth with the proper upgrades. couple that with a clutch and sticky tires, and look out. my buddies 89 turbo t/a runs a 12.20 at 110 with only a chip, better convertor, and adjustable wastegate. his 60' times were in the 1.6s. that doesnt seem like turbo lag to me. he couldve easily gotten more with more mods, but wanted to keep stock apperance and resale value without having to make major changes to return to stock.

the first g-techs run the mph waay high, roughly 6-8 mph high. just ask the guys at tesla.

kopbet89c4

Well, I got so addicted now that I "accidentally" sprayed on my way to work and now I am overheating. I got it to 260 deg and the red light came on. Oops! It climbed up to a max 265 and leveled down to 245 and stayed right about there. When I started it again after my break, it went all the way up to 255 and climbed to 260 again when I let it idle for a while. I popped the hood and I saw some bubbling near the intake. I think its either coolant or oil or even both. Hmmm... time to take the heads off...

I'll keep you all posted.

I think I'll have to buy my neighbor's junker for $1000 obo. At least it has AC... Haha

JCD

Here's your proof:

700+ HP TT and 12.28 @124.

HP is BS.

lilviv

Well, I see you have stumbled across my website, but I think you are either confused or mistaken.

That 12.28 at 124 mph was on my stock turbo setup . . . stock turbos on the car without Nitrous . . . so about 450 RWHP. Good run for a near stock car. The car now carries over 700 RWHP, but I have not taken it to the track since.

Not sure exactly what you were referring to as "BS" in your post above . . . but I think you were just mistaken. I hope this clears something up. TTYL! :-)

kopbet89c4

Back on topic. Finally blew the head gasket. I didn't realize that I was running hot for a while when either the thermostat stopped working, and/or just pure abuse from the cylinder pressure going through the roof from my foolish decision to use nitrous. From my own visual inspection, the gaskets are roughly under a decade old. The block is perfectly fine though with a little carbon build up. I see leaks from cyl 2 to 3, 5 to 6, and leaking through the cylinder to the deck from 7 and 8 with also the gasket between them leaking. Time for a good old rebuild. Gotta call Summit for some forged quality parts. Till then, I'll have to use my $1000 beater to get around town.

jimbomill

Hey Mr. Mojo, I know I'm a virgin to the track, (and my car is getting closer and closer to being ready for a nice spring evening at the track), but I can't follow the post.
You did a 13.00 and he did a 13.49, and passed you prior to the Finish Line? I am certainly missing something here - I cannot picture the events.

dizwiz24

quote:

This is incorrect. Nitrous has a stoichiometric ratio of about 6:1 when mixed with gasoline. The more nitrous you use, the richer you have to be to play it safe.

Example:

Car "A" makes 300 HP NA, and 400 HP on the juice. Of his total HP (400), 300 of that requires a Af ratio of 12.5-13.5:1. 25% of his HP needs a 6:1 AF ratio. So, (13+13+13+6) / 4 = proper AF ratio, or 11.25:1.





Sorry for hijacking this thread. neat, thats an interesting way of looking at it.

All I know is that my 430 rwHP car made 25 more rwHP that day on that dyno when I went with the one size smaller fuel jets than what NX recommended using for a 100 shot . SO maybe 11.5:1 (with the smaller fuel side jets_ is optimum for my 430 rwHP setup.

If I got a 383 setup w/ nitrous that makes 600 rwHP (on juice) or something someday, then maybe that one size smaller fuel jet will no longer be the optimum jetting size. Id in fact need richer...I didnt know that.

But in my case, leaner was better.

kopbet89c4

Yes, leaner fuel mixtures did seem to make more power at the risk of damaging your engine. Thats the way it always worked with my experience in Hondas. I think thats also what happened since I sprayed a 175 shot for prolonged periods of time with barely more fuel pressure and not necessarily fuel itself. This was a mistake I made that cost me lots of time. Also the super high cylinder pressure I put on the motor /w a faulty thermostat also contributed to my head gasket failure and cylinder head warpage deemed unrepairable by my friend (as an ASE certified auto mechanic) and I. Hopefully my new ported iron cylinder heads will solve the problem if they bolt on correctly.

kenv