DAP Performance Injectors

[Tbird9140]

I have recently been offered a set of 125 Hp DAP Performance Injectors at a good price.  I have a 2000, 3500, 4wd, auto Ram with 330K miles. I am looking to get a bit more power when towing and generally replace the likely, worn out/tired original stock injectors.  I know they are not Bosch, but some people have given these good marks.  Does anyone here have any experience with DAP Performance Injectors, 125 Hp or other, and would these injectors be appropriate for what I am trying to accomplish with my rig.  Any thoughts would be appreciated.

Sorry, I forgot to mention that the injectors I am considering are DAP 125HP Performance Injectors 8x0.009 VCO- VP8X9VCO125

[LorenS]

Many, many people here - including Mopar1973Man himself - run DAP injectors and like them.

[Threadzy]

I’ve been running Dap injectors for awhile now. No complaints. Truck runs great! 

[Mopar1973Man]

Yup. Very true. I've got 7 x 0.010 injectors custom built with VCO nozzles and popped to 320 bar. I've even tried Vulcan Performance +75HP injectors (7 x 0.0085) popped at 305 bar. I been selling DAP products for the last about 7 years. Very Very rare have I had to call DAP for warranty issues.

[Tbird9140]

Thanks for the feedback guys.  I am not sure what "popped to 320 bar" means.  Sorry for the ignorance.  If I buy these injectors do I need to take them someplace and have them "popped" If so, what would be the right bar number for these injectors for my application?  Again, thanks for the help.

[Mopar1973Man]

I'm going beyond the normal. Typically most injector builders will pop them slightly lower than stock. Stock pop pressure is 310 bar or 4,500 PSI. Now for performance most will drop to 300 or 305 bar for better flow. I went the other direction and popped them high at 320 bar v(4,641 PSI). This made for cleaner spray pattern and better fuel economy. This is why I like @dieselautopowerfor my injectors is because I can specify a custom build and they will build to your spec. So there default pop pressure will be fine for most applications but in my case I went out on a limb to gain my high mark... 28.04 MPG on a 2002 Dodge Cummins. Was it worth it? Yup! sure was... 

[LorenS]

On 11/21/2021 at 7:00 PM, Tbird9140 said:

I am not sure what "popped to 320 bar" means. 

It means to set up the injectors (via internal shims, etc) so that the beginning of injection starts at 320 BAR - and a BAR is approximately one atmospheric pressure, or 14.7 PSI (sea level). The injector shop does this, you would not need to take them to another place to have this done.

 

I bought a set of their 8-hole 100HP injectors about a year ago and have so far not found the time to install them 😒. And since a squirrel decided to have a field day under my hood - along with other maintenance required - it may not happen any time soon.

Edited December 2, 2021 by LorenS
Spelling

[Mopar1973Man]

Just some common bar to PSI conversions and the pop pressure spec according to Dodge Factory Service Manual.

 

1 bar = 14.5038 PSI

 

293 bar (minimum allowed) = 4,250 PSI

 

300 bar = 4,351 PSI

305 bar = 4,423 PSI

 

310 bar (stock OE injectors) = 4,500 PSI

 

320 bar = 4,641 PSI

 

327 bar (maximum allowed) = 4,750 PSI

 

Being I opted for custom pop pressure being it takes just a bit more time for the VP44 to reach the pop pressure this makes my timing slightly off and retarded. I'm fine with that being I can fully adjust my timing to what I need to get the most from the injectors. As most found out 28 MPG is not impossible with 150 HP injectors. This custom 320 bar pop pressure I make up on the Quadzilla tuner. Another thing to remember its not uncommon for a injector to settle some after being built and dropping about 5 to 10 bar off its set pressure after about 20k miles. So the extra pop pressure is also buying me extended life on the injectors. The way to tell typically is watch the engine load value and the idle RPM. If the injectors are working correctly there should be a engine load between 2% to about 15% and idle at 800 +/- 10 or so. When injectors are wore out thne the idle will be >800 RPM and engine load typically will be ZERO%. This just shows the pop pressure fell out and the ECM can't defuel enough to hold an 800 RPM so it starts to high higher. 

Edited November 22, 2021 by Mopar1973Man

[Silverwolf2691]

I think im the only one that has had an issue with dap injectors and even then its not too big a deal. My 50s (7x.0085 I think) smoke a bit much at factory fuel with the quad.. Might be nozzle angle or something like that. Havent had time or the spare vehicle to pull them yet. Plus im planning on going bigger..

[Tbird9140]

LorenS Does your post mean that you want to sell your 100 hp injectors?

[LorenS]

5 hours ago, Tbird9140 said:

you want to sell your 100 hp injectors?

No, I'll get to them eventually. Sunday I drove the truck for the first time in a couple months and remembered how much I love it - except the steering.  I need to give the steering box a little 1/8-1/4 turn adjustment to see if that helps.

 

With the wife and kids going to the in-laws for Thanksgiving, I get a few days to myself! If I can score some similar over their Christmas break, I should get the injectors swapped - I'm not very fast at it, unlike some guys around here.

[Tbird9140]

LorenS.  What year is your truck?  Were you planning to swap turbos also?  What are make and model of your injectors, and why did you specifically choose these?  Would love to hear about your results once you get them swapped.

[LorenS]

I have a 2001 with rear disc brakes, so a 2001.5 is what some call it.  I changed my turbo to a HE351W based on price and the experience of BlueOx01 who I believe was the first person on this forum to install that turbo, and which at least one knowledgeable person (I believe it was AH64ID) described as similar to a modern version of the HX40/35 hybrid that Mopar1973Man and others run.

 

My current injectors are just factory reman Bosch.  I chose 8-hole injectors versus 7-hole in the hopes that a higher number of smaller jets of diesel may gain me some small boost in efficiency by providing a finer spray.  I also chose "100 HP" versus 125 or 150HP just in case my Quad failed far from home and I would have to switch back to stock; when I bought the injectors, I had not yet purchased or installed the newer, larger turbo.

My daily driver right now since I'm not traveling to job sites near as much is a 2005 Volkswagen Passat, TDI.  I like getting 40 MPG and it's easier to get my kids in the back seat!

[Sycostang67]

I recently got a set of the 7x.009 VCO 100hp injectors from DAP put in my truck.  They are a tad smokier when cold but it clears right up when the truck gets warm.  So far I'm happy with them.  They were really smoky when I was still running my Edge tuner but the quad has cleared that all up.  I'm working on my "Stupid" tune right now and am just starting to see a little bit of smoke.   

[Mopar1973Man]

2 hours ago, Sycostang67 said:

They were really smoky when I was still running my Edge tuner but the quad has cleared that all up. 

 

That is because the Edge just stacks timing on top of the stock timing of the ECM. This is not optimal at all. Bigger injectors need a good amount of retard to get spooled up then you can advance timing on top more being bigger injectors are going to need more time to heat the fuel to a vapor, then go BANG on time. 

 

2 hours ago, Sycostang67 said:

They are a tad smokier when cold but it clears right up when the truck gets warm.

On the Quadzilla the ECM is in control till warm up mode is completed. Even my truck is a bit smokey on start up and getting rolling. Once out of the warm up phase then the Quadzilla will take over and use your tune. I've got mine set for 140*F for warm up.