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  1. The pulley is marked 3.2 but I believe for the 6.4 that is supposed to be 6psi
  2. Brief update. I went to the track this Sunday after an unexpected invite to a closed event. The Chrysler dealer (Gene's) in Fairbanks Alaska rented the only drag strip in Alaska (Palmer Raceway) which is 20 miles from me but 325 miles from the Fairbanks. This was an event for employees, family and friends plus people who had SRT's and all for free which I thought was pretty cool and thoughtful since many us did not travel to Fairbanks to buy a car from them. I had not reached the 500 miles the builder wanted but i was knocking on the door with 460 miles. Of course I did not bring my drag radials because I had no intention of racing and in fact was still on my snow tires because the car went into the shop with them on and I had no time to change to my all seasons this week. There was no track prep and I did a lot of spinning. 6 passes netted trap speeds between 116.0 to 117.5. My boost gage indicated only 4.5 PSI on what is advertised as 6psi super charger and after my adventure this winter Magnuson noted "well it is only about 5.5psi because the 392 pistons are weak. The belt does not seem to be slipping nor does anything look, sound or act loose. Hopefully it is just my gauge. My car goes back to the shop next Friday to refine the tune while dyno'd and that should provide answers. Best case it is a gauge off by one PSI and worst case, well I won't dwell on worst case, maybe just a smaller pulley.
  3. I am hoping it becomes a fun machine. The back ground: this is my 4th challenger. In 2009 October when Chrysler looked like it was going to die I bought a 6 speed R/T. On Dec. 31, 2010 I bought the last new 2010 SRT 6.1 6 speed in Alaska at a very good discount, pretty much a daily driver and raced as much as I could in the summer months. Put about 150 trouble free passes and several auto crosses on it. I sold it after 36,000 miles in the fall of 2013 and in late winter of 2014 I bought a 2012 6 speed SRT, ran it in 2013 and part of 2014 when a half shaft snapped and after fixing that I glazed the clutch. I sold yet again and promised myself never again. This lasted 4 months and I bought another 2012 auto this time. I had a great season with it racing, an extremely consistent car. I was down to a 12.04x with just drag radials and essentially the trinity 93 octane tune. Of course I could not leave well enough alone and decided to supercharge. Living in Alaska has many good aspects to it and some bad ones. Getting things shipped to Alaska is a bad one. The shipping costs to get a supercharger up here was going to be pretty outrageous. Luke, at Steve Whites was willing to work with me on problem solving shipping and was also offering a lot of advice {including tuning the car remotely the magnuson tune is not particularly good (understatement)}. I ordered the supercharger and fortunately decided not to do the install myself. Written instructions from Magnuson had several mistakes, wrong and missing parts in the kit including the fuel injectors (a bad mistake and not realized until much later) and handheld tuner. The kit was installed by a local speed shop with a good reputation. I insisted on using the tune from Magnuson (supercharger warrenty and a daily driver) so the installer emailed magnuson and installed the tune. The car was immediately dyno'd and I was making 30hp less then before the install. Two tunes later and no real improvement. The installer then looked at the tables with his own hp tuning software and realized the tunes were way off and very high AFR's 18-19's on dyno pulls. This led to heated email exchanges between the installer and the magnuson tuner. The magnuson tuner sent 7 more tunes and eventually the car got up to 465hp but that was the best it could do with the last three tunes. I and the installer then decided I would bring it back in spring for him to do the tune. The car drove fine other then the MDS system was still on and every once in a while it would stumble on acceleration if I did so from about 1500 RPM. I contacted Magnuson immediately about the MDS and stumble and after multiple emails and calls finely got a response but their technical service person could never get answers from the tuner. I never had the opportunity to really drive the car hard because it was winter and snow covered road. March came and I took the car in because I wanted a compression check done before the tuning session in April. The installer tried to talk me out of it because he was convinced I would have more symptoms other then an occasional stumble. The compression was low in both cylinder 1 and 2. About 1/3 of the piston ring was MIA in cylinder one (later found during install down by the catalytic converter). A lot of phone calls and emails were exchanged between myself and Magnuson. They did agree to pay for the cost of pulling the engine and installing it but for nothing else as a take it or leave it (no warrenty because the car is a 2012). I did investigate going to court but the advice was the cost/benefit was not worth it even though the case would be a win (I saved all the emails from Magnuson and the installer had saved his and copies of the tunes from the magnuson tuner). So the car is back with an engine that has been built for 700 plus HP. I am expecting to make 500hp and I should be able to have the engine broken in and the final tune done by the final races of the season, Labor day Weekend. Go team go!
  4. Thanks,’the shop recommend no w/o throttle for the first 250 miles. I have to check my boost gauge which appears to be inop. I have only put 5 miles on the car. I flew home from the lower 48, picked the car up after hours, drove home raised the hood,looked at it, shut it and went to bed.
  5. Tonight I just picked up my 2012 392 A5 from an engine rebuild secondary to piston ring failure. The pistons are forged diamonds (compression is 10.1 to 1), rods are forged Manley, hellcat injectors, comtec gaskets and otherwise basically stock. It is a Magnuson 2300 at roughly 5.5 PSI and otherwise stock. The tune is currently a "break in tune" and for 90 octane gas. My concern is that my indicated AFR both banks is consistently running 14x-15x, usually between 14.5-15.5. I am thinking I should be be running between 11x-12x, opinions?
  6. If I go bigger then I am going to need to start to upgrade other parts of the car to handle the power and I do not have a desire to do this with this car (presuming the pistons last). My goal with this mod is to keep the car competitive with the more recent heard of Mustangs that show up at the track modded, the occasional supercharged Cadillac and of course Hellcats. Most of the Hellcat people who show up are running high 11's to 12's because they can't launch the car. Those who can are in the mid to high tens or very low 11's depending on track conditions (obviously will be faster then me). My goal is an 11.5, I will be happy with 11.6x. Currently I am at 12.04 with drag radials (I think an 11.9x is possible as is if everything went just right) and the generic trinity 93 octane tune. I plan to keep this car for a long time and make it just the way I want it as fun, comfortable daily driver. The next mod will be the interior. If I ever move to the lower 48 I will do work on the suspension.
  7. Update, I am going to go with the maggie because of the $600 price difference and there does not seem to be a significant difference in installation difficulty. The car is a daily driver and will stay at 6 pounds of boost and with a very conservative tune so hopefully the pistons will stay with the car. I would like to thank all of you for your advice even if it seems if I am ignoring much of it. I have the opportunity to do this now and with luck in another 2-3 years I can look at a Hellcat.
  8. An infrequent visitor looking for advice. I am getting ready to add a supercharger to a stock 2012 A5 392 that has 30,000 miles, is frequently a daily driver and the car gets about 40-50 passes a year at the track. I am aware of the potential piston issue and plan to use the supplied kit tune (and race gas at the track). It will be at 6 PSI. I am trying to decide between Magnuson and Edelbrock. I know they both use the same supercharger. I know the Edelbrock has slightly better low end torque due to the runners, the magnuson is currently $600 cheaper during this holiday period from what I can find. Are both kits equal in quality and ease of installation?
  9. If you car can hold it try 2000-2100 rpm and then roll. what pressure are your tires at?
  10. As an update: I finally got the car to the track for a test/tune. Unfortunately I was to inpatient to do things in a scientific method so there is no before vs. after. The car is a 2012 SRT automatic. I mixed 50/50 of Sunoco (100 octane) unleaded and chevron premium (90 octane) for about 1/2 tank full. Loaded the trinity 93 octane tune, pumped the all season front tires up to 45 pounds and put Mickey Thompson drag radials (305/35-18) on and set for 21 pounds. It was cool out at 47 degrees. My best time: 60ft-1.84, ET 12.1926 (113.88mph). My old personal best in my now gone 2012 SRT six speed 1.96, ET12.7757, 109.07mph. This would have been with using torco for the same goal of a 95ish octane and either the 91 or 93 trinity tune and on nitto 555 drag radials 275/40-20. It seems easier to launch the auto vs a manual smoothly (I am not saying it is an easier car to race but it is different). I never had any wheel hop yesterday and only spun badly once. The MPH difference between the two cars is a bit more then I expected. The 6 speed was usually 109's-110's never saw 111. Yesterday the 5 speed was usually 113's and I had a 114.2.
  11. Thanks for the reply's. The gas is unleaded so that is not a concern. I did not realize that oxygenated fuels need a richer setting to take advantage of the higher octane when I bought the can. Speedy, I do not know if this still holds true but a few years ago (there were two refineries in the state then). Alaska gasoline would be shipped to the state of Washington during the slow season here. Interestingly you could by the gas cheaper in Washington then here and Washington had a much higher gas tax. There is only one old refinery in Alaska now and it supplies all the gasoline in the state except at Chevron and Sunoco stations and they bring their own up from the lower 48. Unfortunately no one sells higher then 90 octane.
  12. Hello everyone, I am a very infrequent poster to this forum but this forum seems to have a group of knowledgeable people. Race season starts this weekend and I acquired a can of unleaded Sunoco 260 GT plus 100 octane with an oxygen content of 4.7%. My car is a stock 2012 SRT automatic except for the generic 93 octane tune from a trinity. I plan to mix the race gas with pump gas to get 95 octane for the track. I am starting to 2nd guess myself a bit with oxygenated race gas and am thinking of just using torco which is what I have done in the past. I live in Alaska and there are very few options for unleaded gas (pump gas premium is 90). VP-109 is another option but pricey at $125 for 5 gallons and about 2.5 hours total travel time. Thanks in advance!
  13. It has been a long time since I have posted on this forum (and very infrequently at that) and I might be the only person on it who has an unmodded car besides for a generic tune and drag radials. I have had three challengers since late 2009 (5.7, 6.1 and my current 6.4 and all manuals).The first two I kept until 30,000+ miles and this one has 43,000+ miles. The 6.1 had about 150 passes on it and never had issues other then not great paint. The 5.7 was rock solid reliable although again not great paint. My 2012 6.4 has had one issue and that was two weeks ago when the right rear half axle snapped on a dead hook at 4,000RPM with the drag radials (this is a known risk with the manual transmission cars and a high RPM launch). The 6.4 has 100+ passes on it. None of the cars were/are garaged, winter is 6 months long and temperature range from 80 to -40F. My anecdotal experience is that the cars are extremely reliable.
  14. Pirelli Scorpion Snow and Ice also come in that size and are pretty good. People who race up here in Alaska in the winter swear by Nokian hakkapeliitta but I am unsure if the make a size that will fit a 20 inch SRT wheel. If they do make a tire that fits it will make the Blizzaks and Pirelli seem cheap in price.