No smog Referee?

 

Denver metro has a tailpipe sniffer, they run it up to speed on a dyno. They also do a under hood and underbody visual inspection. Once every 2 years on vehicles over 7 years old. Mine is due next month and I'm on the fence about trying it as is or pulling the kit. There's no reason it should fail as is, but the guys that run the tests are easily confused. 2 years ago they tried to fail me for not having a O2 sensor, I had to show them where they were and that I in fact had the 2 oem sensors and even an extra for the wideband. 3 guys crawling around under my jeep and they couldn't find even 1 of them.

 

Um, You have bigger injectors.

That's funny, at first I thought about the hole in the hood, I forgot you have the painted 'factory option hood scoop'. 'What that, a supercharger, didn't they all come with it when you ordered the hood scoop option?'

In PA they just do a OBD2 scan, no codes- pass.

 

I passed just fine 2 years ago with the larger injectors, larger TB, header, cold air intake, and other mods. I even passed with a badly crushed cat converter that was whacked by a rock. ( it has since been replaced)

 

Where on the intake did u guys put the iat sensor to read charge air temps, I was wanting to read mine on the scan tool so i was going to put it back in the intake but I wouldnt fit in factory location because of S/C plate. Did u drill an tape a new hole?

 

I bought a spare sensor, I installed one in the intake tube before the supercharger to read ambient temps and one just below the supercharger outlet. I drilled a hole in the bottom plate, it does not come pre drilled. Its nice to be able to just move the harness and monitor each one when needed but you will notice a decrease in power by having it read the hotter temps.

 

Ya I was just wanting to read charge air temps to see what they are.

 

Yeah that is what I did, drilled and tapped the 1" tall spacer adapter that attaches to the stock intake manifold. With the 7th injector installed, I see around 100* almost independent of the ambient summer temp when not in boost, mild boost around 140-150*, WOT full boost highest I've seen is 180*. At these temps you will not lose any power. I had much higher IA temps stock.

I do want to add meth/blue windshield washer fluid injection which will knock off 40-50* and bring the WOT full boost temp down to 130-140*. This will add longevity, an extra layer of protection against detonation and 5* more power without having to spin the SC any faster. Win-win-win.

 

For anyone waiting on kit availability, kits are back in stock and up for sale on eBay again.

 

Cobra Marty, what differences did you notice when installing the 1.7 rocker arms? Did it improve the upper rpm range power? Did you loose any TQ? What are your overall thoughts on that mod?

 

Racejeep (which has the m62 kit) has 1.6 roller rockers. My Sprintex XJ is the one with the 1.7 rollers.

They 1.7s seem to reduce the power drop-off near 4-5k. If you're planning to go for roller rockers on a stock cam, 1.7 is the way to go.

 

Would you say the difference it makes is worth the cost?

 

On a stock cam, yes.

 

After all the M90 questions I spoke with the creator of the M62 kit about building a M90 kit. He doesn't think there is a market for it. I started a feeler thread with no input so far. I'm thinking about having a kit built to test on my jeep. I'm curious if more boost can be made with lower discharge temps. A 2" pulley on the m62 is the max it can do in respect to its max rpm and boost. I have a 2.1" and see about 8psi. I would like to get to 12 psi and the M90 would be the way to do it.

 

I honestly think that you could achieve similar performance by just tweaking your current m62 setup. The m62 inlet is about 72mm and just by looking at it, the m62 could easily be ported a decent amount, but finding a throttle body to take advantage of that without having to adapt some other manufacturers TB to it is another story. LMAO.

But, here's what I'd do to your system to bump up the boost and give you more performance.

• 70mm billet throttle body
• TB-to-SC adapter plate bored to 70mm (maybe have Rick Rimmer make you one)
• 7th injector (get rid of bigger injectors that you have and replace with 703 or equivalent for your year XJ) You WILL need the ability to tune fuel and timing running the kind of boost that you want.
• headers
• high-flow cat
• 2.5" exhaust from header to cat
• 2.5" cat-back
• intake routed to cowl (like i did on my sprintex XJ)

You should see 10psi+ with those mods. I wouldn't go much above that because your stock head gasket WILL blow somewhere around 12.5psi and it is very easy for boost to spike that high if you're running 12psi and hit a cold patch of air @ WOT. Trust me. I've already done that and proved that that is where and how it blows. Lol

How cool do you want the charge temps?! My Sprintex XJ will max out somewhere around 145* @8psi and will drop lower and lower the longer you stay in it. I've hit as low as 115-120* @8psi on a 85-90* day.