Detuning large injector nozzles - How to pick injector size for upgrades!

[Tim @ P.I.S.]

Jay I apploud you for attempting to share knowledge to the masses. The problem is there are kinds of fancy graphs that will show this and that.

It's fairly simple. We have done countless tests with A codes and Hybrids of various sizes and combinations.

When we take a 225cc A code with a 200% nozzle and place it beside a 230cc hybrid with a 200% nozzle and run both at the same time with the same fluid pressures and the same PW guess which one always has more fluid in the beaker?

The A code injector. If you don't get the same out come with this exact setup then the injectors are not built to maximize their output and work with the nozzles selected.

Which leads to what the biggest issue we have found over the years. Why would a 250/100 hybrid injector not output more than a 175/80 A code injector when run at shorter pw?

https://youtu.be/hWmR2mk4cVo

 

[PsdPullerJr]

Gonna take a guess here Tim, but at a shorter pulsewidth your not taking advantage of the 100% nozzle. In my thinking they will both flow the same until you reach the max pulsewidth the smaller nozzle can flow, add more PW and the larger nozzle will start moving more fuel. I'm prob way off base here, about to be tagged out lol

 

[Tim @ P.I.S.]

Gonna take a guess here Tim, but at a shorter pulsewidth your not taking advantage of the 100% nozzle. In my thinking they will both flow the same until you reach the max pulsewidth the smaller nozzle can flow, add more PW and the larger nozzle will start moving more fuel. I'm prob way off base here, about to be tagged out lol

A 100% nozzle will flow more than a 80% noozle at all times. The problem isn't the nozzle. Nor weither it is a hybrid or A code. It's the poor injector design that's been used for probably thousands of injectors.

 

[TyCorr]

Im thinking those nozzles both dont move much fuel. Dyno numbers aside, that 100% nozzle needs what, 4ms to empty that 250cc injector?

175/80 will move fuel better on a bench but in the real world you wind up buying all the support mods that you need to run the hybrid anyway.

Conversations sake Ill take your 175/80 Tim. And make 450hp+. In real life, ill keep the 250/200s i bought two or three years ago and make more when I want. And if I need 400 or 450 ill do it with much less tax on everything else.

 

[TyCorr]

A 100% nozzle will flow more than a 80% noozle at all times. The problem isn't the nozzle. Nor weither it is a hybrid or A code. It's the poor injector design that's been used for probably thousands of injectors.

I can agree with that. I noticed a considerable bump in performance by using your 250/200 compared to a competitors. Nothing changed except the injectors. And furthermore that old saying "hybrids with 200% nozzles wont idle as good as stock". Its true my stock truck never idled as smooth as it does with the PIS 250/200s.

We may never agree on the apllication of these injectors but these injectors kick azz.

 

[Hotrodtractor]

Jay I apploud you for attempting to share knowledge to the masses. The problem is there are kinds of fancy graphs that will show this and that.

It's fairly simple. We have done countless tests with A codes and Hybrids of various sizes and combinations.

When we take a 225cc A code with a 200% nozzle and place it beside a 230cc hybrid with a 200% nozzle and run both at the same time with the same fluid pressures and the same PW guess which one always has more fluid in the beaker?

The A code injector. If you don't get the same out come with this exact setup then the injectors are not built to maximize their output and work with the nozzles selected.

Which leads to what the biggest issue we have found over the years. Why would a 250/100 hybrid injector not output more than a 175/80 A code injector when run at shorter pw?

https://youtu.be/hWmR2mk4cVo

I'll gladly send you an excel form that will allow you to make identical graphs to those if you promise to fill them out entirely for both a hybrid 200% injector and an A-code 200% injector and post them up here for everyone to see. Then we can all be looking at graphs utilizing the same formatting and color schemes. Better yet would be to run all these injectors on one flow bench, but I don't know of any truly neutral flow benches and don't want to introduce bias.

 

[lincolnlocker]

good read!! glad to see a couple members post that haven't been around in a while. joe, bill, hrt..

live life full throttle

god bless america and the farmer who feeds your fat ass

 

[Chatham036]

Im thinking those nozzles both dont move much fuel. Dyno numbers aside, that 100% nozzle needs what, 4ms to empty that 250cc injector?

We tune based off the calculation that a 250cc/100% injector will empty in 3.2 ms PW.
This PW value came from Ryan Casserly. Tim's injectors may be slightly different for the depletion rate.

 

[Chatham036]

In regards to depletion rates, here is some palatable graphs that we have saved from a few years ago. I will leave the injector builder anonymous for this.

Injector depletion rate - Stage 1 Single - 160cc / 0%

Injector depletion rate - Stage 3 Single - 238cc / 80%

Injector depletion rate - Stage 3 Single - 400cc / 200%

Injector depletion rate - Stage 3 Single - 455cc / 460%

 

[mandkole]

We tune based off the calculation that a 250cc/100% injector will empty in 3.2 ms PW.
This PW value came from Ryan Casserly. Tim's injectors may be slightly different for the depletion rate.

My injs likely need some freshening, but it seems that my full forces take slightly longer to empty yet still make a little more power when stretched--my 140 file (3.2ms) and the 200 file (3.5ms) are about 25 hp apart. The truck dyno'd on the 200 file at 485 recently and was 500 8 years ago with the same injectors. Max EGT is about 1400 on a pull. It ETs at about 500 as well. Bill's old live tunes are still not worth changing...

One of these days, they will need to come out, but the likelihood of going bigger isn't likely. I'll probably go with a smaller turbo before larger injectors. Im caught below the turbo too much with the trailer on the back.

 

[superpsd]

So if an injector could empty faster by flow mods and such. General theory would suggest that a faster traveling plunger would produce a higher pressure behind the nozzle and thus have better atomization. Has anyone tried to detune injectors that have had sho and flow mods done to them. Granted each shop will still not tell you how they are manufacturing these mods because these mods are "proprietary" to a injector builder.

 

[m_j]

Which leads to what the biggest issue we have found over the years. Why would a 250/100 hybrid injector not output more than a 175/80 A code injector when run at shorter pw?

https://youtu.be/hWmR2mk4cVo

Published on Jun 13, 2015

P.I.S. 175/80 injectors vs. Competitor 250/100 injector
Tested at 2.6ms/pw
OUTCOME:
250=190cc
175=185cc

190 is more then 185. so the 250/100 hybrid did flow more the the 175/80 A.
it seems to me the video proves the opposite of what you are saying here.
with less potential nozzle pressure and a claimed slightly larger nozzle the hybrid put 5cc more in to the beaker

you seem to post weird interpretations of your own testing an awful lot.

 

[TyCorr]

Wouldnt we be expecting similar amounts since the 100% nozzle is a smoothed out 80?

And if the 250 is old and worn wouldnt it begin to flow less, not more?

 

[dillpurdy92]

opcorn: Very Interesting read.

Right 🖒

1994.5 CCLB zf5

 

[BS Hauler]

Thank you guys for having this conversation. This is great info for us non tuners. My question is where is the tipping point in rpm's where the 200% nozzle is better in a dedicated tow rig over the 80% A code injector. Here is my thoughts. I am pulling a horse trailer at about 16,000# with an 02 dually 6spd 4.11 gears. South Dakota and Wyoming have 80 mph speed limits which puts my rpm's around 2,500 rpm's. Would the bigger nozzles give us better fuel efficiency at these rpm's.

 

[TyCorr]

I dont want to jinx myself but my truck has been getting 18-20 since I took the lift off and run 35s. 250/200s. If I run the "stock" tune on my truck its every bit of 350 hp and maybe even a hair over 400. If you hold it to the floor it might hit 1200 deg. Granted, you wint get 18-20 then. At 65 im right at 2k rpms.

 

[lincolnlocker]

I dont want to jinx myself but my truck has been getting 18-20 since I took the lift off and run 35s. 250/200s. If I run the "stock" tune on my truck its every bit of 350 hp and maybe even a hair over 400. If you hold it to the floor it might hit 1200 deg. Granted, you wint get 18-20 then. At 65 im right at 2k rpms.

i wouldn't touch a thing and leave it in that tune. lol

live life full throttle

god bless america and the farmer who feeds your fat ass

 

[TyCorr]

i wouldn't touch a thing and leave it in that tune. lol

live life full throttle

god bless america and the farmer who feeds your fat ass

Not much choice...the daily tune is supposed to be 420-460 and it wont hold more than 50% throttle. Supposed to be a slushbox shipped my way end of last week but im guessing not since I didnt hear anything.

Going back to a 17 deg hpop and leaving it for now.

 

[lincolnlocker]

Not much choice...the daily tune is supposed to be 420-460 and it wont hold more than 50% throttle. Supposed to be a slushbox shipped my way end of last week but im guessing not since I didnt hear anything.

Going back to a 17 deg hpop and leaving it for now.

10-4

live life full throttle

god bless america and the farmer who feeds your fat ass

 

[TyCorr]

10-4

live life full throttle

god bless america and the farmer who feeds your fat ass

But once i get that ***ker im going to a tire fryer....lol

And ill daily the hot tune...up yo the speed limit in about 4 seconds lol