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1% prez........"the jiggler"

229K views 2K replies 163 participants last post by  Mr.Green 
#1 · (Edited)
just finishing up my tj and my buddys tj(wheelsofsteele). he did a 60 front w 60 rear out of a 79 ford. had a rubicon long arm so we changed the upper links in rear, tossed the rear trackbar and built a 3 link for the front. i did a 60 front 14 bolt rear,3 link front, leaves in the rear. streched to 103. i built new arms for the front and 2.5 currie joints. will post up pictures and more detail when i figure out how to get these pictures in photobucket. we started mikes jeep july 29 sun night and finishing it up today. his tj is a 1997 mine is a 2003. there is some diffrent stuff between the years.i will give detail on what we ran into.
 
#1,495 ·
Typically you scan and see what duty cycle your injectors are at. Rule of thumb is to try and stay under 80%. At 100% they go static and stay open, no bueno if one sticks there.

Injector size = (HP x BSFC) / (number in injectors x duty cycle)
Horsepower limit = (Injector size x number of cylinders x duty cycle) / BSFC)
BSFC~.45-.5 from what I've found online.

HP=(25.2*8*.8)/(.5)=326.4HP@80% duty cycle

If you assume a .45 BSFC (more efficient engine)
HP=(25.2*8*.8)/(.45)=358.4HP@80% duty cycle


Copied from How to identify vortec truck engine
"
Fuel injector flow rate is very important to have programmed correctly in your PCM. Find a small 8 digit number located on side of each fuel injector. Here is the breakdown.

25317669, 25320287 - 1999, 4.8L and 5.3L - flows 2.742 gm/sec or 21.8 lb/hr @ 58 psi

25317670, 25320288, 25323974 - 1999-2000 6.0L, 2000 4.8L and 5.3L - flows 3.125 gm/sec or 24.8lb/hr @ 58 psi

25317628 2001-2007 - 4.8L, 5.3L, 6.0L - flows 3.180 gm/sec or 25.2lb/hr @ 58 psi

25326903 - 5.3L L59 Vin Z, flex fuel 5.3L - flows 4.164 gm/sec or 33lb/hr @ 50 psi

12554271 - 1997-1998 5.7L LS1 - flows 3.727 gm/sec or 29.6lb/hr @ 58 psi

12555894 - 1999-2000 5.7L LS1 - flows 3.438 gm/sec or 27.3lb/hr @ 58 psi

12561462 - 2001-2004 5.7L LS1, LS6 - flows 3.781 gm/sec or 30lb/hr @ 58 psi"
Billavista's LQ4 page
Vortec 6000 6.0L V-8 LQ4 Tech Article by BillaVista - Pirate4x4x.com
I'm using 74% of a 41lb/hr LS3 injector and I'm not optimized yet. That's 30.34 lb/hr @100 duty cycle. You're going to be at a higher compression(lq9 vs lq4) so assuming they get your cam right, you'll need more fuel to maintain AFR than I am using, which no stock truck injector is going to give you while maintaining the 80% rule. You need bigger injectors if you're going to run the stock 58psi fuel pressure. "Everyone" is wrong in this instance.
 
#1,497 ·
Erin, here's a scan from when I was testing in Aug.
You'll see Mass Air flow(lbs of air) at 52.929lb/min. Multiply by 60 to get 3175lbs/hr. Divide that by 8 cylinders(injectors) to get 396.97 lbs/cylinder(lb/injector). Then divide that by the air/fuel ratio of 12.3 that my wideband was reading to get 32.3 lb/hr. That's the amount of lb/hr of gas needed to make a 12.3 air/fuel ratio at that rpm. So at 100% duty cycle for the injector, you would need a 32.3 lb/hr injector. If you divide that number by .8, you get the size injector needed to run at 80% duty cycle, which is 40 lb/hr. This is why I put LS3 injectors at 41lb/hr rating in. :thumb: My engine is almost identical to yours except you'll have more compression with flat top pistons making more power if tuned right. :beer:

 
#1,499 ·
what cam duration and loab did you do brandon. i have a couple different suggestions on this.not sure what one i want. the ls6 cam is real mild and i have been told to bump it up a little more if im doing this. yellow springs or orange? did you do the l92 heads? you stay with the truck intake or did you do the car? i am leaning towards the car just because i can drop the engine gaurd more and give me a bunch more visibility in my buggy. they claimed a 10% loss in tourque with the car intake.
 
#1,502 ·
LQ4 bottom end, LS3(l92 with diff valves) cylinder heads/intake/injectors, Edelbrock 90mm Throttle Body(DBC), Patriot extreme springs, EPS 222/230 on 112, lift .600ish.

Don't put a cam designed for a cathedral port head(ls6) in an engine with square port heads(L92). You need to look into a torque cam designed to work with square port heads (L92/LS3). Without dyno number I won't comment on the torque numbers but 10% loss seems pretty high. I think either intake will be fine but the truck intake has longer runners IRRC. Better get the cam right, none of the rest of the parts will matter if you don't get that part correct.



Intake info to look at, basically says it doesn't matter L92 vs LS3.
http://ls1tech.com/forums/generation-iv-external-engine/1365722-l92-truck-intake-vs-ls3-intake.html


You'll find people out there with much more knowledge than me on this, I only know what I've read and what I've scanned on my own.
 
#1,500 ·
the guy im getting the block and heads from, has any intake i want.so i have to decide soon since its all getting picked up the first of the week.
 
#1,503 ·
Erin, whichever style intake you use just don't go with your stock one, you need the new style because you'll no longer have the cathedral port heads to match the cathedral port intake. I seriously doubt you'll lose any power with the car style intake, it'll just move it higher in the RPM range. Not ideal for a crawler, but probably a non-issue for your style of driving. Run what fits your packaging and budget.

You won't necessarily make more power with bigger injectors because engines tend to make more power running a little lean. So you'll be making plenty of hp right until you blow a hole in a piston....sound worth it to you? Get the right injectors, optimize your AFR, and keep yourself from having to do this again next year. We all know you're not easy on stuff, so might as well build it for reliability from the get-go.
 
#1,504 ·
Yea I know I have to switch the intake.I'm leaning towards the ls3 car one just so I can lower my engine guard so I can see more.also they look so much cleaner on the motor.I wanna do it right.b&d told me to take it and put on a dyno for the best tune.mail order is not the best and he was strait with me on that.so I'm going to take it to muskeg an and do it right. Looking forward to this.
 
#1,508 ·
so rcv's coming and new rubber....will have some superior 35 spline stuff for sale for a 78,79 ford dana 60.
 

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#1,510 ·
i just did..:sonicjay: they will be available in april. lifetime warranty 35 spline superior inner and outer shafts.spicer non greasable joints also.
 
#1,515 ·
the joint does not matter, the shafts have a no question's asked warranty.i asked before i bought them.
 
#1,518 ·
i have spicer joints in there.it says they are covered. it does not matter brandon.were i bought them i can always get them warrantied. and they are tuff.so no worries.
 
#1,529 ·
when your shitty spicer joint fails, it is going to mangle your shafts. Warranties aren't all that important when you break on your first run of the weekend and have to winch it out and be a spectator for the rest of the competition.
 
#1,520 ·
Can't pass it up.I'm looking for some sticky 42' s also. I won't be going without enough tires this year. The46 on those wheels are lighter then a 43sx on a steel wheel. We weighed both.it was like 17 PDS lighter each one.so over 60 PDS lighter.
 
#1,531 ·
I backed out on bones tires.wanted bigger after following guys with them at hog wild.plus with my luck don't need tires with holes already in them.was offered some other stuff I can't turn down.
Read top post bones.rcv shafts on there way.
 
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