MN C5 Posted June 12, 2003 Report Share Posted June 12, 2003 After a few delays the motor is finally out of the truck. With the exception of Fuel injectors everything is ready to go for the 427. Still waiting for some 50+lb er's Kinda a goofy deal we are using corvette injectors which have different ends than the truck injectors which apparently don't come larger than the 42lb ones that come with the Radix kit. We had to raise the fuel rails and will have to splice the new ends on for the injectors. It should be on the road later next week.. Link to comment Share on other sites More sharing options...
dcairns Posted June 12, 2003 Report Share Posted June 12, 2003 I guess my days as fastest SS are numbered Can't wait to hear how that swap works out Link to comment Share on other sites More sharing options...
ctrow Posted June 12, 2003 Report Share Posted June 12, 2003 Yeah, I think we are all a little jealous, and excited at the same time. Keep the updates coming. Link to comment Share on other sites More sharing options...
BenKey Posted June 12, 2003 Report Share Posted June 12, 2003 Looking forward to seeing what the 1/4 mile ETs will be. Link to comment Share on other sites More sharing options...
creaker Posted June 12, 2003 Report Share Posted June 12, 2003 So how fast is your SS without an engine? Going to put 427SS emblems on it or leave it for people to discover the fact on their own? Link to comment Share on other sites More sharing options...
BigTex Posted June 12, 2003 Report Share Posted June 12, 2003 MNC5 - I had to do the same thing last year for my Z71. Its no big deal. Here is a comparison between the truck injector (right) and the Bosch type injector (left). The truck injector is 5/8th" shorter than the Bosch type. Thats why you have to shim the fuel rail. You'll also have to make a few minor bends to the fuel rail crossover tube to fit properly as each side will move apart a little. Notice in the bottom picture how I had to elongate the rail mount hole to fit properly. I also had to add a larger O-ring to the fuel return line to keep it from leaking. Most 50 pound injectors are rated a 3 bar, so at out fuel pressure they will actually flow 66.6 pounds. That should be PLENTY big enough for your needs. What are you doing for a fuel pump? Here is what the injectors look like side by side in the fuel rail: Link to comment Share on other sites More sharing options...
Krambo Posted June 13, 2003 Report Share Posted June 13, 2003 BIG TEX, in your opinion, when should one consider a fuel system upgrade during the modification on the 6.0L? (i.e. injectors) Link to comment Share on other sites More sharing options...
zippy Posted June 13, 2003 Report Share Posted June 13, 2003 anyone happen to have the rating on the injectors for an L59? they should be in the area of that size. Link to comment Share on other sites More sharing options...
BigTex Posted June 13, 2003 Report Share Posted June 13, 2003 Krambo - The fuel system on the truck should be OK with the normal bolt on mods. Once you start with internal mods (cam, heads, etc...) or a power adder, you might want to address the fuel system. These injectors are the same ones supplied on the 4.8, 5.3 and normal 6.0 engines. The stock fuel injectors will flow about 25 lbs per hour and that should support low / mid 300 HP to the ground or low 400s at the crank. If you go with a dry nitrous system(no additional fuel added), you'll want bigger injectors. If you use a wet nitrous system, which sprays in additional fuel as well as nitrous, your stock injectors are fine. I'd say that if you get to the point where you are making 450 to the wheels, you need to look into some sort of fuel pump upgrade. That means lots of bolt ons and a 100 shot. Depending on the type of supercharger used and its fuel system components, you may need larger injectors or a fuel pump. The Magna kits ship with larger injectors and a handheld tuner that programs the PCM for the larger injector. Whipple sends out 2 extra injectors that spray into the intake. ATI has a different fuel pressure regulator that increases fuel pressure, making your stock injectors flow more fuel. Several companies use a "boost a pump" that increases voltage to the stock fuel pump when needed. That will basically overdrive the fuel pump making it pump more fuel. Most any power adder, nitrous or supercharger, will work fine on a STOCK vehicle. The companies pretty much make sure that you'll have enough fuel. Once you start adding bolt ons, more boost, bigger shots, etc.. thats when you get into fuel supply issues. The best thing to do is to get a fuel pressure gauge and watch your fuel pressure and see if it starts going below mid 50s PSI. If so, you need to address your fuel pump. For injectors, watch your injector "on time" with autotap to see if you are asking them to be on more than 100%. The PCM will ask the injector to flow what is needed, but doesn't stop at the injector maximum. Say you are at 6000 rpms, there is only so many milliseconds that the injector has to add fuel before the ignition. If you have too small injectors, the PCM will be asking the injector to add fuel for more milliseconds than is physically possible, ie - asking them to be open more than 100% of the possible time. If your injectors are too small, they will be fine at low / mid rpms (as they have more time to add fuel). Only at high rpms will they be too small because the time allowed to inject fuel has decreased. Make sense? Richard Link to comment Share on other sites More sharing options...
BenKey Posted June 13, 2003 Report Share Posted June 13, 2003 Richard - great info. Need somebody like you living next door. I had that in VA, before moving to FL - miss that good advice and helping hand when needed. Link to comment Share on other sites More sharing options...
MN C5 Posted June 14, 2003 Author Report Share Posted June 14, 2003 MNC5 - I had to do the same thing last year for my Z71. Its no big deal. Most 50 pound injectors are rated a 3 bar, so at out fuel pressure they will actually flow 66.6 pounds. That should be PLENTY big enough for your needs. What are you doing for a fuel pump? Here is what the injectors look like side by side in the fuel rail: I haven't done anything about the fuel pump yet.. Any suggestions? Radix comes with a boost A pump I think.. I need to find a larger lower pulley now... Anyone have any ideas for that? Link to comment Share on other sites More sharing options...
BigTex Posted June 14, 2003 Report Share Posted June 14, 2003 MN C5 - If you want the easy route, you can add an in-line fuel pump. Warlbro make a decent unit. Some say its too loud, but it serves its purpose. The best solution would be to drop the fuel tank, and install a larger in-tank pump. Several companies make them. Take a look at www.ls1speed.com in their catalog, they have a few offerings of fuel pumps. If you install a much larger pump, you may need to upgrade the fuel lines to and from the fuel rail. I've heard about those large pumps overloading the return line and causing large fuel pressure jumps. I would stay away from the boost-a-pump. Its only a band-aid solution to your fuel needs. It will be more difficult to tune your truck with a variable fuel pressure device attached and it could cause premature failure of the stock fuel pump. The main reason I went with larger injectors on my silverado was to be able to dump the Whipple aux injectors and its stupid piggyback computer. Trying to tune the truck with that on there was very difficult. The PCM didn't know that the whipple injectors were there, so it had the stock injectors maxed out trying to supply enough fuel. The whipple computer only turned on the injectors after 3500 rpms or so. Anyway, I wanted to be able to tune the fuel properly from 800 rpms to 6500+ rpms. I wish Whipple sent injectors and tuning like the old Magna kits. Link to comment Share on other sites More sharing options...
MN C5 Posted June 14, 2003 Author Report Share Posted June 14, 2003 It looks like their in the tank pump is good for 600hp, thanks BigTex. ;) 255L IN-TANK PUMP KIT INCLUDES PUMP AND GENERIC INSTALL KIT . THIS PUMP RUNS AT A HIGHER PRESSURE THAN TYPICAL IN- TANK PUMPS WHICH IS REQUIRED AT THE LS1'S NORMAL OPERATING PRESSURE OF 58PSI AND WILL SUPPORT OVER 600HP. Year Application Part No. Description Price Add to Cart 93-02 LS1/LT1 IZM398 255L HIGH PRESSURE IN-TANK PUMP & INSTALL KIT $129.99 MINOR MODIFICATIONS WILL BE NEEDED FOR INSTALL Link to comment Share on other sites More sharing options...
gabbett1 Posted June 18, 2003 Report Share Posted June 18, 2003 What does the 427 output? Link to comment Share on other sites More sharing options...
MN C5 Posted June 18, 2003 Author Report Share Posted June 18, 2003 What does the 427 output? 573FWHP w/o the blower. Had to scratch the Electric Water Pump, it had no provisions for the belt tensioner. And the stock tensioner brackets are also used for the blower snout support. It's in the truck, just have to finish up the intercooler, exhaust and change the fuel injector plug ends... Link to comment Share on other sites More sharing options...
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