BigTex

iTrader: (16)

My 99 injectors were killing me They flow 21.7 #s at 100% duty cycle and should be good to ~275 at the rear NA. I removed the whipple computer and extra injectors, so my stock injectors weren't gonna do me any good - I was over 160% duty cycle at 5200 RPMs. I bought a set of 2000 and newer 5.3 injectors, but they only flow 24.6 #s and should handle ~320 rwhp NA, so that wasn't going to do the trick. I sent them back. Then I modified my stock fuel rails, changed the wire harness to a Bosch style connector, and installed 26.4 # injectors from a 99 Camaro SS (thanks Jay). Those should should support upper 300s rwhp NA. I was still over 120% duty cycle on these injectors, and running lean up top, but I could feel the performance starting to come back. Next, I dropped in a set of ford SVO 30 # injectors. At the 4 bar fuel pressure we run, they flow over 36 #s. Those did the trick.

Somewhat feels like Frankenstiens monster when I look at what I have been doing to it, but I love it! Here are a few pics. First one shows the block off plate where the whipple aux injectors were mounted. The second one is a closer shot of the red top SVO injectors and Bosche style connectors.

Richard

BTW - I can now remove or install the whipple in less than an hour by myself ( I have done it several times).

GREGGO

iTrader: (2)

Looks good, so shop time being about $60 to $80 an hour, you will install a Whipple for under $100. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

Seriously though, how much do you think think this will help on the ET's

Maxmumboom

Why didnt you use injectors from the 8.1L? they come flow matched with the magnacharger kit and snap right in. They work damn good too.

really slow truck

damn.... so your finally happy with it? or just happier? how is the tuning comming along? good to hear you finally got some injectors in that thing that were good enough for the task <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

BigTex

iTrader: (16)

The 8.1 injectors flow 30#s at our 58 psi, the SVOs flow 36#s. Also, I paid $200 for the SVOs, the 8.1s are much more.

Greg- I honestly dont think the whipple will push me into the 13s. After running nitrous, the supercharger doesn't even compare. Now, it is nice to have the extra grunt all the time, but the torque isn't in the same league as nitrous. Weighing over 5000 lbs requires all the torque I can give it. I do have a 3000 stall converter with a 2.5 STR being delivered tomorrow. That might make a little difference in my time <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Thanks Bryan. Tuning is somewhat off. To get it done correctly, I should wideband dyno tune it, but I'm cheap. I cant get rid of all KR, but I have raised most of my timing a few degrees. It feels pretty good. Despite what others say, heat is a problem w/ the whipple too.

parish8

iTrader: (6)

what kind of duty cycle are you looking at now? i would think those injectors are still working prety hard. how much taller are the svo/fbody injectors? i just looked at my whipple to fuel rail spacing and there isn't much room there and to make it worse the injector leans toward the whipple pushing the crosover tube into the whipple.

i have a set of 41lb injectors ordered that are suposta bolt/plug right in, i should be able to report on these in a couple of days but they are alot of cash. i wish you were having better results geting rid of KR with the extra gas. how much timing and how much KR are you seeing?

oxidizr

iTrader: (4)

Richard,

Have you checked to see if their was any difference in resistance between the OEM style and SVO style injectors?

Richard

BigTex

iTrader: (16)

Haven't checked the resistance on the injetors. I got the SS injectors tuned in very easily and they worked like a charm. Actually, w/ the SS injectors, I had my ltrims at 0.0 & -0.8, so I don't think I could have tuned them in any better. The SVOs must use a different injector offset, so even though I have then dumping in the correct ammount of fuel, they are off a little in their timing. This makes my ltrims fluctuate at idle some. Once I get RPMs going, my ltrims are near 0. The injectors fit just fine under the whipple. Another 1/4 inch, and I'd be out of room.

Tuning is hit or miss, or I should say the whipple is hit or miss. Depends on how the truck is feeling that day, gas I'm running (oxygenated or not), and the temp / humidity. One day I can get timing up pretty well (near 20) and the next, its back down to 12. The SC does get hot despite the lysholm gibberish that they say doesn't get hot. I can watch my temp gauge go from 180 to near 200 in just few seconds if I run it, and the compressor itself will almost burn your hand.

Day to day driving is improved. W/ my larger tires, I used to find myself driving in 3rd alot for better gearing. I havent done that in a couple of months.

red53gmc

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by BigTex:
<strong> changed the wire harness to a Bosch style connector</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Where'd you get the connectors? How much?

parish8

iTrader: (6)

how much boost are you running? what kind of gas? i will be happy if i can get to a solid 12deg of timing by tuning this thing in. i hope you are around to help me dial in the new injectors. right now i only see about 2deg of timing, asking for 8, pulling 6 with KR, at least i am in the positive range, this is with only 3lb on boost. i am prety sure i have fuel issues.