zippy Posted April 10, 2005 Report Share Posted April 10, 2005 over the last few weeks i've done quite a bit of playing with radix trucks and tuning using the wideband. i have some interesting findings and information that i've run accross. before i get into it though, how many on here have actually ran the wideband on your truck with a radix? Link to comment Share on other sites More sharing options...
BigTex Posted April 10, 2005 Report Share Posted April 10, 2005 I'll be honest, I have a wideband, but have been too lazy to mess with it so far. I've been waiting to get all my mods complete then take on tuning in earnest. Link to comment Share on other sites More sharing options...
TBSS Posted April 10, 2005 Report Share Posted April 10, 2005 I've got the DJ Wideband Commander, but haven't hooked it up yet. I really need to get this vibration issue worked out.....it's turning into a real issue. Link to comment Share on other sites More sharing options...
FuelSlut Posted April 10, 2005 Report Share Posted April 10, 2005 ive got nothin... why dont you tell us what you found Link to comment Share on other sites More sharing options...
moregrip Posted April 10, 2005 Report Share Posted April 10, 2005 I guess I'm part of the "I have a wideband but haven't hooked it up yet" club Link to comment Share on other sites More sharing options...
zippy Posted April 10, 2005 Author Report Share Posted April 10, 2005 well, my findings are from what i can tell the 42lb hr injectors that the radix kit comes with are only just big enough for the stock pulley and good tuning. if you notice the track times from the radix trucks you'll find that the mph is always very low. with two SS trucks sitting side by side and doing tuning work we found that every time just before the shift point on either the truck would begin to creep up to lean. the amount and time is very little and no KR* is present due to this. we found this by installing a 2.8 pulley on an SS this weekend. it was certainly quicker and had we simply tuned it as most i suspect have by adding fuel and adjusting the timing tables to prevent KR*, we'd never have noticed the issue. running the smaller pulley certainly made the truck quicker and even the KR* wasn't rediculous. there was a small amount coming in over 5200 or so though. at this point we decided instead of just getting the timing tables where they needed to be and adding some fuel to the VE and PE tables we'd put the wide band on it. the truck ran a solid 11.8:1 afr by my settings all the way to around 4200 or so and began creeping lean. by around 5200 it was at the 14:1 area and at the shift point it had topped 15.x:1. trying every trick i could come up with to add fuel to the truck seemed to only help minorly and i could never keep it below 13:1 from around 5200 and up. it consistantly was over 14:1 by the shift. to see if it was just my settings we put the stock pulley back on. at this point the same tune resulted in an afr of around 9.2:1-11.3 all the way to around 5600-5700 where it would creap to around 13:1 very briefly and just before the shift so this was acceptable. i ended up retuning the truck back to the settings i had for the stock 3.3 pulley. the other truck sitting there had just had a radix put on it as well as a corsa exhaust. i had modified the airbox some also to get more air in. both trucks on the stock radix tune never showed lean because of the low timing tables and lower shift points. lower timing tables means unburned fuel and of course shows up as being rich. with a properly worked over timing table and wideband VE and PE table both trucks would go lean in the same spot which was about 50-100rpm just before the shift (lean being over 13:1 in this case). the 03' truck we had sitting there had a freshly installed walbro 255 in it and fresh fuel filter. we figured we'd test for a fuel volume issue by re-installing the auxillary pump. running both the walbro and auxillary pump did not change the issue. i know that when dcairns bought his radix it had a 3.1 pulley on it. the later models come with a 3.3. i believe this is more due to fuel requirements rather than the compression issue. it's been shown more than enough times that the smaller pulleys have no issue even on the stock radix tune driving around and having acceptable KR*. running the stock very rich radix tune will even allow for a smaller pulley and not show an issue because of the very weak timing tables and rich as hell program. with weak timing the KR* doesn't show to be an issue therefore even on a better tune such as a mail order tune one only watches for the KR* and never even bothers to check to see if the truck is lean or not. having driven the same truck with a 2.8 pulley and a 3.3 pulley, i'd say it would have shown gains in the quarter because the truck was so much quicker in the lower rpms and it crosses the traps before going lean in 3rd due to rpm becomes a problem (caused by the tall tires). i'd certainly like to see some more wideband numbers on this. the truck we put the 2.8 pulley on we ended up taking it back off until we can get bigger injectors for it an try again. i just didn't feel safe letting it go like that. of course our colder and more dense air up here in michigan only makes the problem a bit worse. with the only mods to this truck being my tunining work, a trailblazer converter, and a zippy kit, the truck went a 13.64@98mph. this is with a non-removable subwoofer box still in the truck and a heavy fiberglass toneau cover still on it and in 75 degree weather. taking away the 200 or more extra pounds would have netted some gain as will an exhaust, etc. i think that the reason the radix trucks are consistantly being held into the 13's even with going to the smaller pulleys and upping the boost considerably is these damn small injectors they come with. i feel a radix truck tuned with larger injectors and a smaller pulley with the average bolt on's would be dead into the 12's like the procharger trucks, etc with the same amount of boost (which comes in considerably earlier). Link to comment Share on other sites More sharing options...
TBSS Posted April 11, 2005 Report Share Posted April 11, 2005 So what are you thinking, 60-pounders? Link to comment Share on other sites More sharing options...
MN C5 Posted April 11, 2005 Report Share Posted April 11, 2005 I ran a wide band on mine. Its been awhile but I think I started out with the injectors supplied with the kit on my 427. They did run out of fuel but I expected as much. The bigger problem was keeping the fuel pressure up even with the boost pump supplied with the kit it crashed the fuel pressure at 4800 or something like that. I don't think a stock 6.0 with a stock pulley is going to max out a 42lb injector... That would be like 500rwhp or more... Could be but I'd suspect the fuel system before the injectors. Link to comment Share on other sites More sharing options...
BenKey Posted April 11, 2005 Report Share Posted April 11, 2005 Would monitoring inj duty cycle show the problem? How many pounds of boost did you see with the smaller pulley? Most Radix guys are seeing around 8.5 max. Also, aren't the Procharged trucks running more boost? 12lb on one of them. They are using the same 42lb injectors. 60s would be way too big. Not hard, but a PITA to change over to LS1 style pigtails. 42 is as big as they get for the truck pigtails. Also need to raise the fuel rails. Link to comment Share on other sites More sharing options...
zippy Posted April 11, 2005 Author Report Share Posted April 11, 2005 the procharger systems as far as i know are still currently coming with an FMU and relying on the stock injectors. the couple of kits i am aware of that people have bought from procharger with the 42lbhr injectors include their own programming (handheld like the radix). these kits are often only designed to run around the LR4, LM7, and LQ4 and make 8-9psi with the supplied pulley and do not likely run the rpm where this is an issue. most that are running a procharger didn't actually buy a kit. i guess the question should be extended on from there. how many of the procharger guys have ever put a wideband on their truck? i see alot of mail order tunes for them also. the 2.8 pulley on this truck made around 9.5psi. going from the info that i have if i recall correctly the lightning is recomended to have larger injectors installed once they crest the 400rwhp (somewhere in there by memory). they come with 42psi stock and use the similar eaton roots blower. i'd guess on the 03' with the 255 in tank walbro and the auxillary pump hooked up that fuel supply should be fine. Link to comment Share on other sites More sharing options...
BenKey Posted April 11, 2005 Report Share Posted April 11, 2005 '03 kits only "came" with the inline pump to go along with the stock in-tank. The '04s and above use a single walbro in-tank, single pump. You say you tested with an aux pump and 255. Your initial testing was just with the 255? Was the aux pump the ones the Radix comes with for the '03? You saw no corresponding drop in fuel pressure? Link to comment Share on other sites More sharing options...
zippy Posted April 11, 2005 Author Report Share Posted April 11, 2005 on the 03' we had a drop i pressure at first causing the switch to the walbro. the stock pump would almost never prime enough pressure for it to start without a good 10-15 revolutions. once the radix was on there even the aux pump that came in the kit couldn't fix the failing stock pump. from there the 255 was put in since there isn't much reason other than being cheap to put another stock pump back in. the point of installing the radix auxillary pump back on was simply to ensure no pressure drop. by this point it was so late we'd have been unable to read a fuel pressure gauge in the dark. the walbro 255 and aux pump we were pretty sure should be able to handle the stock radix fueling. Link to comment Share on other sites More sharing options...
MN C5 Posted April 11, 2005 Report Share Posted April 11, 2005 the walbro 255 and aux pump we were pretty sure should be able to handle the stock radix fueling. Yes, but so should the 42's. Looks like the only thing left to check is the FPR Link to comment Share on other sites More sharing options...
FuelSlut Posted April 11, 2005 Report Share Posted April 11, 2005 i went 13.55 this weekend, trap of 96.35 mph (corsa, radix, 2.9, zippy kit & trail blazer converter - as well as a JL audio non-removable sub-box) vs. a 2001 camaro ss (headers, cut-out, gear, suspension & air lid - many of the major bolt ons...) which ran 13.52 @ 100.44 mph. I talked with Bryan from PCM4Less before the outting at the track and he had convinced me to switch plugs to Autolite 103's with a .035 gap (he said with the CHP truck they ran into "blowing out the spark" - oddly enuff on my camaro buildup both trick flow & holley reccommended Autolite plugs - prior to that i dont think i would have even put autolite in my lawnmower.... but in all honesty it seemed to have helped. Anyone know what 8.1L injectors flow? and whether or not their compatiable? (i havnt seen enuff 8.1's around the shop much)..... Zip, what do you think? Link to comment Share on other sites More sharing options...
hank Posted April 11, 2005 Report Share Posted April 11, 2005 id like to here more about this. what would you guys suggest for someone like me to do? Link to comment Share on other sites More sharing options...
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