HPJunkie

RumRunner,

What do you think about the air from the blowers blowing across the carb throat using the prochargeror vortech box? What about using a "hat" ( no box)? What do you know about jetting for these situations?

HARDCORE A/O

HP:
I know what you're thinking. I've never liked the design of the Vortech box because of the side entry and the way the entry into narrows down as it enters the box. Also, the fuel feed lines stick up in front of the entry and that must cause some turbulence as well. I can only imagine that this is not the optimum for air entering the carb, especially at high RPMs. I also remember Tomcat saying on a previous post that he tested the flow on one of these things and the air flow was not impressive (like 750cfm if I remember correctly).
I also see on Superior Airflows website a dyno test that they did on a small block Ford with their Extreme Velocity "hat" which made like 35 hp more than the Vortech box.
I'm pretty sure I'm going to buy one of their O-ringed hats to try, since it's only like $223.
However, I've also seen an article in Hot Rod where they made over 1000 RWHP on a small block Chevy (408 cid) with the Vortech box, so it's capable of making serious power. I have no doubt in my mind that my motor is making around if not over 1,000hp too, but hell, more is always better!

BTW: I forgot to tell that I have the intercooler rigged to an ice chest full of ice water which I pump through the intercooler. This thing really supercools the I/C to the point where its frosty and I'm sure that this helps make power too. The only disadvantage is that by the time you make two runs the ice is gone, but thats not really a problem -ice is cheap and I just keep a huge ice chest to refill it when I come back to the dock.

cobra marty

Have you done any inlet temp measurements with your ICE I/C vs. seawater to the intercooler. Even if ice is 35 degrees and the seawater is 70 degrees you might only see 10 degree intake temp difference which is only worth 1% HP increase or 10HP on a 1000HP motor for all the ice hassle.

HARDCORE A/O

No I haven't Cobra Marty, but thats something I would like to know though. I can't be sure what the exact temp differential is, but I know that right after a run the intercooler is sweating and very cold and the carb box itself is cold to the touch so it is a noticeable difference. I'm pretty sure the difference isn't only 10 degrees. BTW: sea water temps down here right now are like in the low 80s. The real reason I wanted to do this was to help eliminate detonation and I like the fact that I'm not pumping salt water through the i/c anymore too. Thanks for the tip though. I'm going to do some testing with this and compare the difference in inlet air temps and speed with ice water vs. seawater (once I get the boat propped right) and I'll run a thread on that when I do.

TW720HVY

iTrader: (1)

Same question but for fuel injected motors? What effect will 93oct with E10 and without E10 have on O₂ readings? Most of the time it'll have E10 but some of the rural gas stations around the lakes will have ethanol free 93.

14 apache

iTrader: (1)

Bump

Tinkerer

what about us guys that run NA
I recently had a situation where my engine was running real rich. The engine had been run with only 11 volts and this is an EFI engine. It fouled out plug on the side that had the O2 sensor. Needless it ran like crap but seemed to clean up and fire on all cylinders at full throttle.
The boat seamed to accelerate better in this rich condition than how it accelerates now with new plugs and running properly.
My question is would it be OK to rich en up the ratio between lets say 2000 and 6000 RPM in the top three bands.
I figured that the only time is is going to be at full throttle at that RPM range is when I am hammering on it.
Then once it gets to 6000 RPM I can lean it up just a little.
I also have a scoop that is sealed to the flame arrestor.
What are your thought on this?

Tinkerer

The EFI is a HOLLEY HP sequential port set up.
I have a bunch of Global files including one from HAXBY SPEED.
They all have almost the same A/F table. Almost no difference between them.
When I slowly increase the throttle I get a lean condition and sometimes will get a lean pop.
Do I just change the acceleration curve?

sutphen 30

depends,does the data show it getting ae fuel,if not then try upping the slow throttle opening part of the ae graph.if not,your gonna have to richen up the fuel cells that are being used.what are your afr's?

kvogt

At cruise or steady throttle I run an efficient A/F ratio and timing ; as I accelerate the A/F ratio richens up quite a bit and the timing is pulled back a couple degrees.
Over lay some of your cruise datalogs on your target A/F map and richen the target above that line. Do a similar plot on your timing table. Then run the boat in closed loop (above 1600rpm) with the learn on and the computer will fix your fuel table for you.
You can also lean the target A/F and add timing below the line. This will add timing and lean out your deceleration.