lean or rich mixture

[strokin96xj]

ok so i'm about to start my 4.6 up for the first time 96 xj. my question is do i have to worry about it running way lean or way rich when i start it up and do the cam break in? i have bigger injectors but the stock fpr and stock pcm. will i be ok to run the motor to break it in a drive it or should i buy like a chip and take it somewhere to be tuned before i start it to make sure i dont' run it too lean or rich? thanks for the help and i hope this makes sense lol.

[dwg86]

I don't have an AFR gauge on my 2003 wrangler yet, so I don't know what my AFR is doing. I have 24# EV6 ford cobra injectors. I broke my cam in with no problems. I have got 3000 miles on my stroker now. Plugs look good...light tan color.

When it's cold and running in open loop, it has a slight rough idle, but It doesn't smell rich. I don't know if it's the cam duration causing the rough idle(214 [email protected]). I don't concider that a big cam. When breaking in my cam the engine never got hot. I was able to run 2500 rpm for 25 minuets, and my header never got red.

If you want to base your break-in on my experience, I think you will be ok.

[strokin96xj]

alright thanks anyone else got any suggestions or answers?

[YJason]

I think you'll be fine, my engine and ECM is from a 96 XJ I have the 24lb cobra injectors, 64mm TB and a AFR guage and it ran 13.9-14.3 when cold and 14.5-14.9 when warm while doing the cam break in.

[strokin96xj]

ok thanks and as for getting a AFR gauge can i just buy one from like advance autoparts like a cheap one or should i get a more expensive good one?

[gradon]

A wideband o2 costs about $60-75 for the sensor and a gauge costs another $75-100. Some used innovate lc1 or lm1 kits go for $100. They provide the software so that you can log afrs to a laptop.

[dwg86]

Some info on piggyback computers and tuning. I sent Hesco a question about using a piggyback computer and tuning . Here is a reply I got...

The 2003 PCM has a fair program (you did not say auto or manual) with plenty of timing at wot, could use more at lower rpm and load.

The UniChip has given a large number of customers the added performance they were looking for when building engines.

I have programs for that spec engine that will improve the performance: as to the value that is your call!

The UniChip is not calibrate by user and has to be done by me, I have a program where you can download from a laptop or desktop computer to the UniChip and select different programs from our web.

The cost for this unit is $750.00 and comes with everything you need to install and download.

You are able to talk to a tech that can adjust your program to your requested changes. You get 5 free cals after that 99.00 each. Most hit on second or third download. The other advantage is when you change something you can re tune without having to buy a second UniChip.

So i figured the $750.00 was not worth a few extra ponies. Its a daily driver not a race car.

[gradon]

If I lived w/in 8 hours of Alabama, I would have bought the Unichip from hesco and had them dyno-tune it(closer to $600 w/o the download cable). Paying $750 for a "custom tune" that hasn't been dyno tested is ridiculous. I bought mine for $400 new off ebay(loaded w/ a "k&n intake, header, cat-back" tune for the 4.0), but still have to pay a tuner $100-175/hr to tune it so I will be paying the same price that hesco is asking, but will know the tune is specifically for my jeep as it is with its mods and I'll have the dyno chart. The Unichip added ~50hp/60lb-ft @the wheels to comanche91's 4.6 jeep(hesco could've been a little liberal, but even half that amount is amazing), so I would say that the correct tune is worthwhile in extracting that extra 10-20%.

[dwg86]

Comanche91 was an OBDI. I would like to see the tune results for an OBDII. What is your stroker going in?