Boostec Supercharger Information

Status
Not open for further replies.
We had a Rep from Sprintex out this week and it was decided to add a 1 Bar MAP to act as a barometric sensor which effectively gives constant altitude correction. This is really needed here in Colorado as massive altitude changes are the norm. We tested it from 4,700' (downtown Pueblo) to better than 10,000' (around Woodland Park) with a broadband O2 installed so we could monitor the AFI. Saw a total varience of between 12.2 to 14.7. Biggest varience was at 5.5" boost close to the rev limiter (114mph). At 80mph with near 700 pounds of passengers and equipment running into a 25mph headwind, the XJ delivered 18mpg per the OHC.

Not too shabby...

The TJ has the new P&P harness in and we will be replacing the original "cut up the factory harness" version with a P&P harness on Monday, April 19. Guess I'll have a busy day putting the factory harness back to stock... On the XJ the third MAP mounts just at the drivers side hood release spring. As we have it, the stock Air Box still fits. Will get photos on Monday once the P&P harness is installed. On the TJ, it mounts on the firewall.
 
You are nearly correct. Not quite garbage, just not quite right. One of the goals will be to compare OHC Avg Mpg to actual and see if we can come up with a conversion percentage. Not likely, but Due Diligence is required. Most of the time, the Perfect Power Piggyback is NOT adding fuel to the system and the boost gage reads Zero. That is as should be. It is only under relatively high Throttle openings and, of course, WOT, that the boost rises out of vacuum into positive pressure. Right now, the Shop XJ only has a boost gage on it, I am recommending a Vacuum/Boost gage be installed to better monitor what is going on. One does, however, have to assume (I know...) that if not under boost, then you are under vacuum. As long as the engine is operating under vacuum conditions, then the OHC is as accurate as it ever is.

I should appreciate and constructive comments that members can give. The more we contribute, the better the system gets.

And the first system has been sold so, away we go...
 
The OHC mpg is based off the injector pulse widths of the stock 22-23# injectors. Larger injectors with the same calculated pulse widths are shooting more gas in, so mpgs are way off(garbage, lol). Do the ole fashioned miles vs gallons used calculation.
 
Uh... Running stock injectors plus the seventh. So, the calculation is correct as long as you stay out of boost map in the Perfect Power which is most of the time.

And we will do the math manually as inquiring minds want to know.
 
My bad, must've been thinking of someone else's boosted app with 3_#injectors. So is the smt8 increasing the pulse width at all on the stock 6 injectors?
 
Yes, if you stay out of boost with stock injectors you will have a fairly accurate measurement. As you say you probably won't get a conversion percentage for the OHC MPG. The problem is that that percentage will be based on when the 7th injector is firing. Which will be based on how lead footed the drive is. Of course which will vary between people. If you had a way of calculating how long that injector has been open over a given period of time (since last fill up) you should be able to calculate the %.

So is the smt8 increasing the pulse width at all on the stock 6 injectors?

If it is, as long as it is running it through the MAP sensor and allowing the PCM to control the stock injectors than the PCM's fuel calc will remain correct.
 
The SMT8 is altering the timing and adding fuel via the seventh injector. For the most part the PCM with stock injectors run the engine. Under boost, the SMT8 retards the spark and adds fuel. With the addition of the ambient barometric sensor, the kit will not have to be retuned for any location in the world on an otherwise stock engine.

You see, Oz is sort of flat... Mount Kosciuszko at 7,310' is the highest point on the contenent and it's not like people drive up to the top on a regular basis as, say, they do here on Pikes Peak (elev 14,115'). Which explains why the idea just did not occur.

The goal is to provide a system that anyone who can install an exhaust header can easily install. No altitude tuning required. It is also a goal to setup Authorized Installation centers around the US to handle those that need the extra help.

As of Saturday, April 16, 2011, the OHC was showing 21.1mpg after the trip to take the Sprintex Rep down to Denver International so he can wend his way back to China. Lots of 2500s (etal) in China...

As I said earlier, the first XJ kit will be shipped to Puerto Rico and all of the Mini kits that arrived are gone... In fact, we are now backordered.

Lets talk Cam Shafts. With positive pressure, the need for a high lift cam (on the intake side) is eliminated. You would also want to avoid valve overlap for the same reason. I do not know of any Cam Grinder that makes a boosted specific cam. Does anyone here know?

Another side note, I have asked Rick to consider becoming a NAXJA sponsor. We will see how that goes.

You know, this started as a request from some of you good folks to go and take some photos and do some fact finding. It has turned into something really fun for an old, retired, disabled guy. Sure the time I can spend sitting and watching is limited to maybe an hour every other day, but Rick and his employee are doing a great job of keeping me in the loop as they find better ways to tweak the SMT8.

For the record, I am not in the pay of Boostec or Sprintex. I am not receiving any form of compensation from either company. I have volunteered my rig for a test bed should they decide they need another one but the title to any hardware installed will be retained by the respective company that installed it and is subject to being removed at their request at any time. Whew...
 
Lets talk Cam Shafts. With positive pressure, the need for a high lift cam (on the intake side) is eliminated. You would also want to avoid valve overlap for the same reason. I do not know of any Cam Grinder that makes a boosted specific cam. Does anyone here know?
Hesco offers a boost cam. They are made by Clay Smith cams. You can talk to any number of cam grinders for a custom boost cam. Howard cams, UDHarold, Clay Smith, Isky, Bullet cams, are just a few people you can talk to.
 
I have personally picked the lunati 63501 for my boosted app
 
The XJ got back from the Easter Jeep Safari in Moab. The trip averaged 24 measured mpg at an average of better than 70mph. Not bad for a brick on wheels... My stock XJ gets 18.5 on the hiway which I thought was pretty good.

JP Magazine was there, took a test ride and was impressed. I think we can find an article inthe not all that distant future. Take into consideration that Magazines have long lead times. JP was also very interested in the Golectric water pump setup and would like to see that article first. Progress is made.
 
Status
Not open for further replies.
Back
Top