Alky Pressure/Volume Test

4sfed4

New Member
Joined
Mar 2, 2004
I made a quick trip back to the dyno last Saturday to retune the car after adding a second alky nozzle. After the runs I made back in October with the alkycontrol.com PAC kit with a single M15 nozzle, I found that the car made great power (500 whp), but it was a little bit too lean up top for my liking. There was no knock retard, but in the interests of long term life, I wanted to spray more alky. My gasoline delivery was also maxed out. Thus, the addition of the second alky nozzle, which was an M10.

Since Julio is local to me, he came to the dyno with a 0-300 psi pressure gauge, some braided hoses and the appropriate fittings to tap into my alky feed line so we could watch alky pressure under boost on the dyno.

Well, the second nozzle certainly did the trick! We were able to get A/Fs right down where I wanted them. With the single nozzle, I was creeping on 13.5:1 way up top, but with the second nozzle, we were able to get a nice flat 11.8-12:1 up top. The car was actually making a little better power for a given boost level than last time, but we couldnt get the car to make 34-35 psi boost on the dyno as I see on the street. I guess the load just is not there with an inertial type dyno on my small engine which needs all the load it can get.

The alky pressure ramps up in a HURRY with the settings I have on the PAC. (I need to have an aggressive reamp due to how this turbo spools. When it reaches its threshold point, it shoots boost up to peak almost instantaneously.) Under full boost, we saw a peak of 170 psi alky pressure even with the twin M15 and M10 nozzles spraying full tilt. And, the pressure needle didnt budge.

I calculated out the alky flow rate and its about 2225 cc/min. The 15 gph (M15) and 10 gph (M10) nozzles (a total of 25 gph when rated at 100 psi), end up flowing about 32.6 gph at the measured 170 psi pressure. Methanol is about 6.5 lb/gal, so thats 211.9 lb/hr, which equates to 2225 cc/min. Thats alot of spray! My base gasoline fueling works out to about 208 lb/hr, or 2184 cc/min.

I have a video of the pressure test, which is shown below. Please right click and save as----

http://mysite.verizon.net/res1elpe/alkypressure-large.wmv

When you do the right click and save as of the file, make sure to specify the file type as "all files". Youll then physically have to type .wmv after the file name. For some reason, when an attempt is made to save the file, it defaults to an .htm type. I have no idea why its doing that :mad:
 
I love tests

For those looking at the video, its a 300 PSI liquid filled guage. 150 PSI is the center point. You'll watch the needle climb as the boost on the motor climbs.

Looks like the needle surges... not ;)

:D
 
Whoo boy! When full boost hits and alky starts flowing....that thing sounds mean!

So how much HP/ torque gain was there now the A/F is correct?

Mark
 
Originally posted by Hyboost4Banger
Whoo boy! When full boost hits and alky starts flowing....that thing sounds mean!

BAH! That run that we recorded the alky pressure was the first run of the day under low boost. The car sounds way better with more boost! I guess most any car would sound angry if you cram enough boost down its throat.

So how much HP/ torque gain was there now the A/F is correct?

Mark

Well....I have now given up on Dynojets :(

I have had problems in the past with not being able to hold full boost (from what appears to be a lack of load on the dyno as compared to the street). This problem reared its ugly head again last weekend :(

So, I couldnt get the car to hold more than 27 psi boost. It would spike higher, but wouldnt hold it. I tried both 3rd and 4th gears with the same result. So, I couldnt get a good run in at the 32-34 psi boost the car makes on the street. (After finishing on the dyno, I took the car out on the street and promptly hammered it. POOF! The boost went right back into the low 30's and stayed there.)

So....I really dont have a good power number compared to last time other than to say the car is safer than before and seemed to make a little more power than last time for a given boost level. (Last time at the dyno, the boost seemed to hold a little better. But, I am not 100% sure about this either as I am relying on the dyno operators assessment of the boost pressure for the runs made a couple of months back. This time on the dyno, I drove the car and watched the gauges. The boost was nowhere near what it is on the street. ) I am still waiting on the dyno files from the shop (they promised them to me and they still have not arrived), so I cant state the actual numbers. But, off of memory I believe the runs ranged from like 460 to about 500 hp depending on boost/fueling, etc. Pity we couldnt get the 32-34 psi seen on the street as I think 550 would have been reasonable.

But, I do know the car is running richer than last time and thats all I really cared about anyway. In the future, I think I will switch over to a non-interial type dyno (such as a Mustang) so that the drum load can be better matched to the actual load the car sees on the street. I wish I switched to a Mustang type dyno sooner, but I have made so many Dynojet runs that I wanted to stay consistent so comparisions could be made.
 
This may seem stupidly simple question......but have you checked for boost leaks?.....may help to your unstable boost scenario......check for boost leaks by pessurizing your turbo inlet with compressed air and listening for (hisses) "leaks" and watching how fast your boost guage drops. I found that much over 30 psi chances of boost leaks leaks double. I T-bolt clamp everything!

That turbo you have should make way more than 30 psi...
just a thought anyhow..always good to check basics.

Cool music with your dyno movie.........

Mark
 
Originally posted by Hyboost4Banger
This may seem stupidly simple question......but have you checked for boost leaks?.....may help to your unstable boost scenario......check for boost leaks by pessurizing your turbo inlet with compressed air and listening for (hisses) "leaks" and watching how fast your boost guage drops. I found that much over 30 psi chances of boost leaks leaks double. I T-bolt clamp everything!

That turbo you have should make way more than 30 psi...
just a thought anyhow..always good to check basics.

See....thats the thing. It will make as much boost as I want on the street, but not on the dyno. Thus, my conclusion of inadequate dyno drum load.

I have a feeling if I dynoed on a Mustang Dyno (where the load can be adjusted), I would get a more realistic result.




Cool music with your dyno movie.........

Mark
A buddy from the turbododge list made the video. My skills are limited to pressing the record button :D
 
Geez.........The liquid filled guage dampens the pressure pulsations of the Shurflo pump....that's what liquid filled guages are for!!!

Should I upload a video of a test with a STANDARD pressure guage????? That'd be an eye-opener....

Try it with a 0-100 psi standard guage once.......and maybe it was the way the controller was set, but it sure looked like it was instant on, not progressive.......
Who knows...I don't care to argue.
But if someone slams my kit I have to respond.
 
Originally posted by SMC
and maybe it was the way the controller was set, but it sure looked like it was instant on, not progressive.......
Who knows...I don't care to argue.

If you saw how fast this SC6152S goes from 8-10 psi to 30 psi it might explain why the alky pressure rises so fast. Honestly, the boost needle jumps that range so quickly that its like a switch was flicked.

The controls were set for an 8-9 psi turn on, the initial was set conservatively and the gain was set aggressively.
 
Larry.. shhh.. your giving away secrets... plus at 500 WHP on 93 octane and methanol..not much to explain. Guess a video is worth a thousand words.

BTW, did you get the package in the mail.. call me and i'll explain :D
 
Larry, what spring PSI is in the wastegate actuator you are currently using?

If its stock or pretty low like 8 or 10 psi, you might want to see if you can modify a GN actuator with a tighter 18psi spring or even larger to help keep the puck tighter. I believe someone made a removeable one for the user to customize.
 
Originally posted by 4sfed4
See....thats the thing. It will make as much boost as I want on the street, but not on the dyno. Thus, my conclusion of inadequate dyno drum load.

i agree. when i dynoed my GN, 49 turbo, 25 psi, smc single nozzle they put it as weighinh 3000 lbs. it had NO knock at all but made stock HP numbers but at a 7:1 A/F as indicated by their wideband. when i would take it out on the street tho. it was clearly makin more than stock numbers
 
Originally posted by DR.BOOSTER
Larry, what spring PSI is in the wastegate actuator you are currently using?

If its stock or pretty low like 8 or 10 psi, you might want to see if you can modify a GN actuator with a tighter 18psi spring or even larger to help keep the puck tighter. I believe someone made a removeable one for the user to customize.

Mine is failry loose. Its a stock actuator off of a non intercooled Turbo Dodge (which ran 7-8 psi boost)! I have it set not so that min boost is about 10-11 psi.

Ive got it tightened up a bit, bit its still a tough balance between actuator travel and tension. A better actuator would certainly be of benefit. I havent fiddled with it much as in the back of my mind I keep hearing this voice saying....."external gate..external gate". LOL. But, the fab work, etc for that is what has kept me fom pursuing it.

Some GNs came stock with 18 psi min boost actuators? Or, they can be retorfit with one?
 
Originally posted by turbo buicks
i agree. when i dynoed my GN, 49 turbo, 25 psi, smc single nozzle they put it as weighinh 3000 lbs. it had NO knock at all but made stock HP numbers but at a 7:1 A/F as indicated by their wideband. when i would take it out on the street tho. it was clearly makin more than stock numbers

7:1 A/F!?!?!? There must have been a puddle under your exhaust tip :D
 
there was. and i had the dump opened so the gas fumes had everyone coughing and their eyes watering hahahah GN OWNED them!!!
 
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