I guess it must just be a coincidence. I removed the spacer on advice from a friend and the code never came back. The engine seemed to run better too, which was an added bonus.
Easy Power Mods for Jeep TJ 4.0 Thread
- Thread starter Kaptainkid1
- Start date
OP
OP
Here are Dyno numbers for stock, 4 hole and 12hole injectors.
Also cold Air intakes on the dyno for 4.0l.
I think I will put snokel and enlarge the Air box.
Apparently you can get a few horsepower.
I already have the 12 holes installed.
Interesting that you loose about 45 horsepower to the wheels from the Auto Transmission and sold axles.
Also cold Air intakes on the dyno for 4.0l.
I think I will put snokel and enlarge the Air box.
Apparently you can get a few horsepower.
I already have the 12 holes installed.
Interesting that you loose about 45 horsepower to the wheels from the Auto Transmission and sold axles.
The differences are small and could be chalked up to small differences in the flow rate of the injectors changing the a/f ratio. I'm not discounting potential benefits of those injectors, but I am saying that dyno test wasn't exactly conclusive proof. I would suspect a tuner would notice improved ability to dial in idle and part throttle stuff, especially with a big cam. I'm skeptical of people claiming miracles and 2mpg boosts in economy though.
There is a large jump in the fuel air curve on the first two sets at about 3k, maybe that's where the operator floored the Jeep not realizing the max torque readings would be below that point or maybe intentionally trying to change the results and not realizing the fuel air curve would show what happened so clearly. With all the runs you can see the max torque was below 3k. Who knows what really happened but be careful of what you see on the internet. I don't really know how they did the runs but there's enough there for me not to consider this useful at all.
Easy power mods... the title of this thread alone is a huge misnomer 
Hey bro, maybe some 4-hole injectors will atomize my fuel and give me more power! Totally dude!!!
Hey bro, maybe some 4-hole injectors will atomize my fuel and give me more power! Totally dude!!!
If you're into it then go for it but just like the injector bit I wouldn't expect much. After all, they didn't put on a cold air or a snorkel with a filter, they removed the filter entirely which isn't really an option I'd consider.
Mudflat
TJ Enthusiast
I’m a retired refinery operator & I made gasoline & other products for a living. Additional octane does not increase horsepower. It’s ONLY function is to decrease or eliminate pre-ignition knock. Sure if you have a high performance engine with high compression it will knock &, therefore, run like crap on 87 octane gasoline. There could even be damage with long term use. Jeeps fun fine on regular unleaded.
One more thing; the concentration of detergent additives (7 gallons per 1,000 barrels of gasoline) is the same for all 3 grades & all refiners follows the same thing.
My favorite power mod is to turn the overdrive off on the automatic transmission.
Same here. Even with 5.13's so many 6-8% grades in my town. I turn it off every drive pretty much.
I have discussed it a fair amount with people who use them in builds or run them but I don't have one. What are you wondering about?
Would it be worth it to replace a perfectly functioning head with it? On a stock'ish rebuild with out a lot of other power mods? No.
True horsepower gains come from angry grills, overhead light bars and 22" rims with low profile tires.
