Joe,
What fuel pressure issues did you have with the 238's?

 

I wish I would have gone that route with my F450 instead of the stock rebuild. After reading several of Joe's (CSIPSD) posts it seems like AC's are definitely the way to go. I probably missed the boat by sticking with split shots...
I will be very interested to read your post and see what your results might be.

I am interested in the topic of nozzle size also. While it sounds logical that oversized nozzles will make more peak HP...I wonder what effect they may have on the torque curve. In the back of my mind I have been suspecting that stock size nozzles may have a broader torque curve which may be more beneficial for towing compared to oversized nozzles. However I have no real world experience with various nozzle sizes so I am left speculate and wonder how things might turn out...

I was really hoping to see the extension of this thread
PHP's 2001 F-250 Build. Finally! - Power Hungry Performance Forum
to see the differences between nozzle size in graph form. Post #12 has three data files for download that has a bunch if interesting info.

The #1 and #2 tests are with stock injectors and pretty much confirm what Joe (CSIPSD) has been saying in this and similar threads in relation to peak HP figures.

Test #3 is with what they have labeled "Stage 1" and are Singles 160/30 units. As best as I understand the labels...these injectors are single shots, 160 cc/1000 strokes with nozzles that are 30% larger than stock. By looking at the dyno tabs and graphing the torque curve it appears a bit 'peaky' compared to the HP graph (which is much flatter). Of course the PHP "extreme" tune may be completely different than a more traditional every day tow tune so the graph profile might change as the calibrations vary. One thing is for certain, 160cc Singles are able to make 33% more peak HP compared to 140cc Splits so that is quite impressive considering the volume of fuel is only a 15% increase. So, that leads me to believe that Singles are far more efficient than Splits.

It appears the next text (#4) is planned to run what they have labeled "Stage 2" injectors which are to be Singles 160/100 units. I would really like to see that graph just for a comparison's sake between nozzle sizes. If peak HP increases with the same amount of fuel then I would expect to see some change in the torque profile since HP is derived from TQ & RPM. I wonder if nozzle size is one of those things where each option has it's own benefits depending on the use or if we could simply go with the largest nozzle possible and let the tuner control the power delivery with the calibration maps.

I am pretty close to jumping in head first and start tuning my own trucks but I am not sure I am ready for that challenge just yet.

 

Yes, Joe what do you do for a living? And where did you get this. Its very good information, it would help alot of guys in there choices.

Chet

 

I am a Construction Superintendent for ESI Construction. Travel all over the western us building, remodeling and such big box retail buildings.

Was in Santa Fe, NM this time last year, then Colorado, then Boise, then Grants Pass, OR, then Henderson, NV, then Bakersfield, CA, then Great Falls, MT, then Springfield, OR and now Bakersfield, CA again...LOL. Thats just this year.

Most of my info is on Diesel Bombers as stickies, but also most of it has been written by others, Geoff Thomas on the injector write up and Matt of GearHead on the HP formula.

I've been driving this motor since 95... Worked on my own trucks since then...

 

Greg.... fantastic link! I tried to rep, but I have to spread 'em around.

This gives me what I'm always looking for - data. I can see a real benefit to the Single-Shot 160s with the 30% nozzles.

I am piecing together all the information I can muster and one spec eludes me. As I understand all of this, the "stock" nozzle is always .006. does that make the 30% nozzle .0075? What is the 100% nozzle - about .009?

Side note: I'm looking at brand new Full Force injectors to be shipped and I will swap them out here (near my home). Between the turbo and injectors, I'll need over $4500 up-front until I get the old sticks back to them for a $1200 core return... assuming my old sticks get the full refund. I make a very good living (wood-knock here), but I doubt I have the financial/technical-support rescources that Joe has in the event of my making a mistake. This is not one of those things I do on a whim... so some can see why I'm uber-thorough. My "anality" is how I make my living, it has kept me out of debt (saw the mortgage crisis coming), and it has kept me out of trouble (my stuff holds together) thus far, so I plan on remaining the most **** sumbich I know. I appreciate everybody's patience with what may seem as inane questions, but I do have use for the answers.

 

I have AC's and a 38R in my F350. With my current tuning I struggle to pass 1200* EGT at 24k lbs GCVW even pulling steep grades with the skinny pedal pressed hard to the floor. The truck dyno'ed 320HP in this tune and made 370HP in my 'hot' tune. There is basically NO smoke in the tow tune, which is what I drive in most of the time. The only smoke at 370HP is the moment I leave the line or just after I stomp it when there is no boost. This truck is a blast to drive and gets the same MPG as 'stock'.

Fuel pressure with a stock fuel system (except in-tank mods ) is not a problem for me with AC's. If FP was an issue, I'd run parallel PSD pumps - especially since they can be found for $40 these days.

I also ran 175/146's for a long time with stock charger and tuning that left alot to be desired - of course I didn't know that until I tried something else... On current tunes, my trucks (the X is all stock) are MUCH quieter now with higher ICP, less smoke, lower EGT's, more power, better MPG's, etc. - it was a BIG difference over the old toons.

When I got the AC's, I wanted 80% nozzles - but there was a communication breakdown (my fault ). The benefits of the bigger nozzles are worth the cost. Being able to put the same amount of fuel into the combustion chamber in less time means more optimum timing. This is why single-shots are better than split's. Early injection drives CP's up and late injection increases smoke and EGT's.

Fwiw, I wouldn't do the 38R and bellowed up-pipes again. IMHO, T4 + S366 or similar is a better way to go.

 

I just want to skim this and move back to the injectors... I hope this doesn't spiral into tune bashing: Without divulging names - did you have to change hardware, or just get a different supplier of the tuning?

 

LOL... a drastic change in hardware.

 

That was tactfully answered. Got it

Does anybody have specs, or a link to specs on the nozzle diameters?

 

It depends on the type of process to enlarge or create the holes...

Dont go by size...

Example, my 200% nozzles flow 45-47lpm (liters per minute)...

 

LPM, not LPH? At what back-pressure do they arrive at that flow? Is this per stick? Yeesh. Are you pulling a cruise ship through the locks in Panama?

 

Well shame on you, Rob! I've mentioned this a few times and Joe has posted this a few times too!

C'mon now, you gotta stay up on EVERY thread and post a little better than that! Pay attention now, there's a test at the end of the week!!

Stewart

 

I know Stewart, so much going on and getting ready to retire from the air force, my head is just spinning. I swear I'll do better at paying attention.

 

Thanks Joe. I can see you have a lot of knowledge on the subject. Missed you at the last morgan hill get together. I'm pretty sure I'll be in Wyoming for this one as well. Been gone with the wife for a few days also.

Chet

 

Well, Joe, youve convinced me, not just in this thread but in lots of others on the subject over time. I looked all over the net in the places i know and cant find that setup. It was seldom that i found AC injectors, but they were all stock. Would one need to send the injectors out to have nozzle modified after purchasing stock? All the popular injector providers were touting numbers similar in regards to their Stage 1 or Stage 2 injectors. Are these modified injectors (AD etc, Stage 1,2) the same as a modified AC? Im trying not to get caught up in the stage label and look at the numbers, but it can be difficult sometimes when looking around. Where would be a good place to purchase AC's?