Recommend Injectors, Turbo 4.0...

[live24wheel]

Long story short, I am new to turbos, for the most part. I am boosting one of our Team Clapped Out XJ buggies, yes, on the cheap I don't care too much if it grenades, side. Specs are, stock 97 4.0, tons of miles, eBay 57t turbo, eBay WG and BOV, 8psi, Split Second FTC1 and Aem Wideband. I will be picking up a set of 1 step colder plugs to go in as well. I will be running the stock fuel rail, etc. Keep in mind, my fuel pressure is the 49psi flavor. It seems most of the builds I'm finding are the older obd1 and 39psi.

My dilemma, there are a few but not a whole lot of turbo'd 4.0's out there, at least online. I have searched and searched. The best thing I can find is to run 30lb injectors, but it seems most of them are on the older fuel supply system. Anyone have some input, or part numbers?

This is a lot of a learning experience for me, hence a lot of cheap parts incase I screw it up. I can replace the motor and the ebay turbo crap for less than the price of just one quality turbo... Lol

Any advice is appreciated!

 

[live24wheel]

Oh and I have purchased pretty much everything except the FTC1 and injectors and plugs. The reason I chose the FTC1 was, well, everyone seemed to recommend it other than a few that chose a different route. I'm no programming wiz and the comments seem to make this look about the most user friendly. Wouldn't mind some input on that as well.

 

[O-Gauge Steamer]

The question that needs be asked is "How much boost?" This will drive the selection of the injectors. The AFR needs be 14.7 during "cruise" operation and the injectors need to have the reserve flow to be able to provide fuel to get the AFR to the mid 12s under acceleration.

I am running 8 pounds of boost here at 6,500' altitude which is about 9.5 pounds at sea level. The injectors I am running were selected at a time when I thought I was going to be tuning the XJ for E85. As a result, they are "over sized" for a strictly gasoline (E15) application.

I use the AEM F/IC8 as my controller and I have a set of 40 pound injectors installed.

So then... It is a difficult question to answer until all of the operating parameters are known. As for part numbers, the internet is your friend...

 

[live24wheel]

Long story short, I am new to turbos, for the most part. I am boosting one of our Team Clapped Out XJ buggies, yes, on the cheap I don't care too much if it grenades, side. Specs are, stock 97 4.0, tons of miles, eBay 57t turbo, eBay WG and BOV, 8psi, Split Second FTC1 and Aem Wideband. I will be picking up a set of 1 step colder plugs to go in as well. I will be running the stock fuel rail, etc. Keep in mind, my fuel pressure is the 49psi flavor. It seems most of the builds I'm finding are the older obd1 and 39psi.

My dilemma, there are a few but not a whole lot of turbo'd 4.0's out there, at least online. I have searched and searched. The best thing I can find is to run 30lb injectors, but it seems most of them are on the older fuel supply system. Anyone have some input, or part numbers?

This is a lot of a learning experience for me, hence a lot of cheap parts incase I screw it up. I can replace the motor and the ebay turbo crap for less than the price of just one quality turbo... Lol

Any advice is appreciated!

Sorry, I didn't make it very clear and kinda mixed it in there. 8psi is the plan.

 

[SolarBell]

From the PseudoSport XJ-R thread:

We are running 36 lbs injectors from a supercharged GM 3800. I've seen around 85% duty cycle at 7 psi. A slightly larger injector would be nice but the 36 lbs were free and work for now as long as we don't crank the boost.

I have 30 pound Venom injectors on the shelf waiting to go into my supercharger setup, I am expecting around the same amount of boost. But I'm running around at over 5000' of elevation.

 

[Dr. Dyno]

I was going to suggest 36lb'ers and since the engine's going to receive FI, it's better to err on the rich side at WOT with an AFR of 11.5-12.0 especially with stock pistons.

 

[live24wheel]

From the PseudoSport XJ-R thread:



I have 30 pound Venom injectors on the shelf waiting to go into my supercharger setup, I am expecting around the same amount of boost. But I'm running around at over 5000' of elevation.

I was under the impression the XJ-R was running the older 39psi fuel pressure, unless they changed it out and I missed it, which wouldn't surprise me. If im not mistaking, doesn't the injector pound rating go up with higher fuel pressure? As in, the injectors are rated at 30psi @ a specified pressure. Correct?

 

[SolarBell]

I was under the impression the XJ-R was running the older 39psi fuel pressure, unless they changed it out and I missed it, which wouldn't surprise me. If im not mistaking, doesn't the injector pound rating go up with higher fuel pressure? As in, the injectors are rated at 30psi @ a specified pressure. Correct?

Yes, they are running the 39 psi rail. I was unable to find the rated pressure for the stated flow rate on the Venom injectors. However I do know that on O-Gauge's setup with 40 pound injectors, the high pressure rail, and 8-ish pounds of boost his duty cycle is well under 25%.

 

[JEEPERDK]

boostworks is running 40lb ford injectors on his 1999 stock 4.0L turbo XJ

heres his write up on his turbo build if u happened to miss it:
http://www.naxja.org/forum/showthread.php?t=1031285

and here is his actual build thread:
http://www.naxja.org/forum/showthread.php?t=1059015

 

[live24wheel]

Ok, got an email back for split sec. He recommended 30# injectors. However, I had to ask 30# at what psi? Perhaps I am over thinking this. He also stated that I must have JTEC ecu. Best I can tell is that being a 97, I should have that???

 

[live24wheel]

Got another email back...

Tom,

Most injectors are rated at 43.5 psi. If you take an injector that flows 30lb/hr at 43.5 psi and run it at 49 psi, it flows about 31.8 lb/hr. That is comfortably within the range of injector size that is a good match for your application. The JTEC ECU is used on Jeeps from 1997 to 2004. It has three connectors that are black, white and grey

 

[live24wheel]

Ok, last question. Those injectors, anyone have a p/n die what will fit the 97? Not sure of I want/need Bosch, Accel, or?

 

[live24wheel]

After talking to Five O I went with Bosch 0280155759. They are a EV1 style injector/plug with the "gen 3" 4 hole pattern. Also inquired with Split Sec about running a step colder plugs and he said not to worry about it with the FTC1. Placed the order for injectors which leaves nothing left to get other than various exhaust pieces etc...