everyone check this out tell me if im wrong..

[TType84]

alright.. i have been wondering why i (having a hotair that is) cant run as much propane as anyone else..

i know i know i have a stock'ish car that only ran 13.6's before.. so lower hp is one of the factors..

but im saying i have to turn it WAY down.. the duty cycle knob is below 15%, i have a "60" jet in there

bottle pressure is below 100psi, i need a refill.... if i got a refill i would probably have to turn the boost even farther down.

SOOOO here is my theory..

propane is heavier than air right?

Propane
Molecular weight : 44.096 g/mol

Oxygen (i think this is pure oxygen.. so the air we breathe would be heavier due to having nitrogen and whatever else in it, right?
Molecular weight : 31.9988 g/mol

so, my turbo is spinning 100,000rpm and all of a sudden a substance that is 1.37 times denser hits the blades and slows them down..

is the extra 12.098g/mol enough to matter when it comes to a turbo spinning at a hundred thousand rpm or so?

ALSO

i know the kit has a jet in it.. but you guys have your.. well lets use 100 psi i guess, so, 100psi bottle pressure working against say 25psi... so that brings the effective pressure down to 75psi

mine is in the intake path before the turbo.. so i have 100psi bottle pressure working against a HUGE AMOUNT OF VACUUM.... well i dont know how to measure it w/o another boost gauge but im gonna ASSume its far enough on the opposite side of the spectrum from 25psi to make a difference..

thoughts... ideas.. help? anyone?

 

[snistrgn]

Uhhhh...yea...sorry i've got nothing. Way too many numbers for me. On a side note I think I saw your car the other day sitting across from the shop. It was at the tint shop across the street in Mesquite last week.

 

[TType84]

yea they are f'in crooks dude i freaking hate that b....

she did 2 ****ty jobs in a row and blamed it and said i had chipped glass..

CHIPPED ?? ON THE INSIDE? HOW WOULD THAT HAPPEN?

and there is freaking trash and dirt all in there.. i just want to file a complaint with the BBB or somethin, id rather have a refund cause they do ****ty work.

i went back to get everything fixed and it came out worse than before...

where were you? the tire shop?

 

[mycarsucks]

I know it would be really hard to mount the nozzle after the turbo on one of our hotair cars, but would you try being the sacrificial goat by reclocking the turbo, and running a some tube from it around the front of the intake and then into the intake hole. It's pretty possible, I did it, but slipped an IC inbetween the turbo and the intake.

This would answer many of your questions. I think that you have a very strong point with injecting into vacuum versus boosted line.

 

[snistrgn]

I'm sorry to hear about your tint man. I work for my dad at the muffler shop on main st.(check sig.) I've got the hook up on tint so if you want it done right lemme know. I just got mine done and it looks sweet. Limo(5%) all the way around.

 

[TType84]

well.. ive never used the turbo's mounting bolt.. the little stud that pokes out of the side, so if i can find a nozzle that will screw into there.. then bam, i have it made.

if i clock the turbo and run the pipe, im putting the volvo intercooler i have in the garage on first..

 

[Turbo__Tim]

So you are reaching 'flood stage'?

You kow maybe you are just using the propane more effeciently...

My little theory is you are creating a more homogenous mixture by putting it through the turbo first. This is how the propane works after all. (it isn't the cooling, cause inlet temps don't change)

Do you plan on running it again soon? You may "already be a winner" with a few tenths improvement.

(gees I've been waiting for someone to post before and after race results!) It would be great for the hot air guys if this works really well...

Sorry to hear about your chipped window. Hard to understand how that could even happen

Guess the messy shop should have been a warning.

 

[TType84]

well, here is how it went down.

i took the car to the dyno.. it was running like crap.

my maf is going bad i think, my motor mounts are bad enough to cause it to knock hard right when you get on the gas, so there goes all my timing..

and then the boost would waver smoothly but quickly from 20 to 10 to 17 and back to 10

the car *has* to be slower than it was when it was stock right now..

it ran a 13.6 with only a jay c chip, electric fan, and a cracked open exhaust. 13.6@98mph goin by MPH @ 3500lbs says the car would have to have atleast
Rear Wheel HP - 223.7
Crankshaft HP - 279.6

to run that speed..

the car currently has these extras: 2.5" atr dp and a stage 3 cheetah in a hotair housing.

so that should be good for a whole f'in lot more than 215.7hp@4400rpm and 336.4ft-lb@2600rpm, which is what the car dynoed when it was acting retarded..

im shooting for 300hp at the wheels.. and i *should* be able to get that.. so im gonna put on the motor mounts, get a translator, and put my cold air kit back on...

once i get the car running right on the street im going to take it to the track and go as fast as possible on pump gas then switch on the propane and crank the boost.. if that goes well then i will put it on the dyno again... the track is cheaper than the dyno though, so i know im gonna go to the track first..

 

[S10xGN]

Interesting, but there were turbo systems in the past that used carbuerators in draw-through" mode, so imagine what liquid gasoline droplets would be like hitting a 100,000 rpm wheel!

On another note, what about putting the Propain injection nozzle on the inlet side (between the MAF and the turbo) so the bottle pressure would not be diminished by the boost pressure???

 

[Turbo__Tim]

Your goals sound realistic. I'm betting you in the 12's very soon.

A cracked exhaust is ok, but a cracked headere will skewer the 0-2 readings since the 0-2 sensor will 'see' the oxygen that has been pulled in there, and comand the injectors to open, adding more fuel.

I mention this just in case you or others were not aware of this. Many MAF changed for this reason...

 

[cwmccray]

HEY NICK
I HAVE BEEN FOLLOWING YOU AND THE PROPANE ON YOUR HOT AIR, I THINK PROPANE IS GOING BE TO BE TOO MUCH IN THE TURBO. I AM TOYING WITH THE IDEA OF USING 2 NOZZLE IN THE INTAKE. WE ALL KNOW THAT THE HOT AIR INTAKE HAS A DIVIDER
DOWN THE MIDDLE. BY USING A DUAL NOZZLE OR A NOZZLE ON EACH SIZE OF THE INTAKE, THE PROPANE SHOULD EVENLY CHARGE OR FOG THE HOT INTAKE. YOUR APPROACH, SIMILIAR TO LEE THOMPSON USING ALKY, WOULD REQUIRE A VERY, VERY SMALL AND PRECISE SHOT OR STREAM AS FAST AS YOUR TURBO IS SPINNING. THE ONLY OTHER ALTERNATIVE IS TO PLACE THE PROPANE IN FRONT OF THE THROTTLEBODY, SORT OF LIKE NITROUS. LETS SEE, WE ALL KNOW HOT AIRS LOVE NITROUS, SO THEORITICALLY, THEY SHOULD LOVE PROPANE EVEN MORE . BY INJECTING PROPANE BETWEEN THE TURBO AND THROTTLEBODY, THIS MAY SOLVE THE SITUATION. 87-86 BUICKS INJECT BEFORE THE THROTTLEBODY, BUT THEY DON'T HAVE A TURBO BEHIND THEIR THROTTLEBODY.

GOOD LUCK

CHUCK MCCRAY

 

[JayC]

I dont think that's going to work.

I think Nick has the best injection point available on the hot air cars now. He just needs to work with it a little more.