Gas mileage

If the overhead mileage numbers are spoiling your fun, put in larger fuel-injectors and have your engine re-tuned for those. You will see a major boost in fuel economy numbers; well according to the overhead anyway...
True it will be calibrated wrong hahaha
 
City driving is a killer goes straight up to 20-30l/100km
there has to be a simple way to make them more efficient without massive costs and power loss .. more efficient usual cause a power increase with better mileage though. Not sure anyone really ever tried as these trucks only get modified to make a ton more power …
 
I dunno.
Even with really good high swirl and fast-burn cylinder heads, an 11:1 comp ratio and a cam that builds cylinder pressure early, fuel economy is not that great.

I know the 48RE isn't helping either.

It does get better mileage than when it was brand new but the fuel savings are gone with more w.o.t. fun.
 
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there has to be a simple way to make them more efficient without massive costs and power loss .. more efficient usual cause a power increase with better mileage though. Not sure anyone really ever tried as these trucks only get modified to make a ton more power …

I dunno.
Even with really good high swirl and fast-burn cylinder heads, an 11:1 comp ratio and a cam that builds cylinder pressure early, it is not that great.
I know the 48RE isn't helping either.
It does get better mileage than when it was brand new but the fuel savings are gone with more w.o.t. fun.
Someone needs to take the plunge and do an 8HP70/90 swap. Ridiculously simple for the 04-05 PCI trucks and even simpler for the CAN based 2006's. The main caveat is that it isn't cheap.
Parts cost so far for the swap that I will be doing:
Sound German harness - $1000
8HP70 - trying to find a good used one under $2000
Car style e-shifter - $120, I'll have to do some custom work to the console but not a huge deal
Custom driveshaft - has to be a custom slip shaft (so probably in the neighborhood of $1k or more) since the ZF doesn't have a slip yoke and to mate to the D60

SG harness in PCI trucks only require hookups for 12v constant, 12v switched, ground, brake switch input, TPS, RPM, and reverse light output to function. CAN trucks it can be made plug & play.
 
o_Oo_O
there has to be a simple way to make them more efficient without massive costs and power loss .. more efficient usual cause a power increase with better mileage though. Not sure anyone really ever tried as these trucks only get modified to make a ton more power …
If you want efficient buy a Hyundai! That's what I did and it gets about 28 to 30 on the freeway. Worked for me o_O
 
I dunno.
Even with really good high swirl and fast-burn cylinder heads, an 11:1 comp ratio and a cam that builds cylinder pressure early, fuel economy is not that great.

I know the 48RE isn't helping either.

It does get better mileage than when it was brand new but the fuel savings are gone with more w.o.t. fun.

I owned a 1973 340 duster 8.5 compression that got 10.5 miles per gallon city and around 13 highway .. 727 transmission and single trac 273 gears in the rear .. all factory ran strong and ran properly all tuned using the Sunoco 280 highest octane pump gas . I decided to make it a positrac rear and swapped it out , it had 355 gears , put in I think. 2500 stall converter and shift kit , super stock springs and a adjustable pinion snubber to limit axle wind up . Used an sig erson on cam and cam time advance key .along with some 273 cid adjustable rocker arms . Holly race electric fuel pump and adjustable regulator. edelbrock manifold and oil splash shield and a holly 750 double pumper carb with externally adjustable jets , lighter vacuum springs. MSD full ignition system and a accel super coil , 8mm plug wires . Added a moroso cool can for cooling the fuel . Installed aluminum coat headers , center line wheels and stuffed the fat tires into the rear with wheel tubes added . Many other things … after doing all that I was getting 27 miles per gallon city and in the mid 20’s Highway .. and it was a lot faster .. I relate it to the efficiency of the engine parts and changing the total gear ratios . Then I got a little more radical and added nitrous and finally found my factory dream six pack manifold and holly carbs which after 11 years Summit racing had reproduction ones for sale . 1350 com total on the carbs when needed and ran around just using the primary holly 350 com 2 barrel and my mileage improved even more . But the fun factor really was fun when the 2 outboard 500 cams kicked in .. with the nitrous it ran in the low 10’s in the quarter . The fun took out the motor because the hurst slap stick decide not to make the shift and knock knock it went for about 2 weeks while I searched for another 340 engine.. couldn’t find one and had to settle for a 360 cid .. jus about all parts are interchangeable parts interchangeable between the 2 .. the problem it was a junk yard 360 with to many miles and I was in Vegas away from home in Va. on a road trip for 7 months ugh ! I did make it back home for Christmas ,, But having just been divorced and she robbed all the bank accounts .. it sat And didn’t have the cash to fix it back up . Then my Brother had it towed away to I have no idea. I was in SC at that time . Oh was I pissed and still am .. that all happened when I was 28 and am pushing 66 now . I should really beat my brothers you know what for that but have know resigned to the old saying shit happens and karma has already visited him many times lol .
 
o_Oo_O
If you want efficient buy a Hyundai! That's what I did and it gets about 28 to 30 on the freeway. Worked for me o_O
Hun this is not the day .. never happen hahaha :D heck my 202 dodge Dakota doesn’t get much better gas mileage than the 10 barely 14 city ,, never been on a highway with it .. but my last girlfriend owned 2 Prius’s and both surprised me with power and leg room in the back seat hahaha . She’s then traded out for a Camaro and trade that for a grand sport Vette .. she loves vettes but won’t race me and my 10 .. even though she has a lead foot . She’s about to turn 75 next month .. the pics are hers ! And they say teachers don’t get paid enough hahaha she retired 10 year before full retirement hahaha !
 

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Hun this is not the day .. never happen hahaha :D heck my 202 dodge Dakota doesn’t get much better gas mileage than the 10 barely 14 city ,, never been on a highway with it .. but my last girlfriend owned 2 Prius’s and both surprised me with power and leg room in the back seat hahaha . She’s then traded out for a Camaro and trade that for a grand sport Vette .. she loves vettes but won’t race me and my 10 .. even though she has a lead foot . She’s about to turn 75 next month .. the pics are hers ! And they say teachers don’t get paid enough hahaha she retired 10 year before full retirement hahaha !
Very nice! Glad that all worked out for her :cool:
 
What kind of power levels will they handle in stock trim??
8HP70 is the standard auto behind the 5.7 & 6.4/392 hemis. Latest version stock 392 is rated 485hp/475tq; that puts it 50 lb-ft shy of the Ram Viper engine, though the HP70's have been fine behind somewhat modified 392's. They can also be built up fairly easy (but probably not cheaply). There is a 2004 quad cab running around with a 6.1 based 392 stroker (run by a Holley standalone that is somehow talking to the factory gauges) and an 8HP70.
The 8HP90 is the stock trans behind all Hellcat, Redeye & Demon engines. Lowest power Hellcat is 707hp/650tq; think we're good there lol. Redeyes are 797hp/707tq, Demons came in 2 flavors of 840hp/770tq and now 1025hp/945tq.
Something to note, the 1320 Scat Pack and Demon transmissions come with factory trans brakes that can be activated in another vehicle.
 
Very nice! Glad that all worked out for her :cool:
She’s slowed down some now .. she only mows her 3 acre property , plants all flowers every year , mulches and paints both homes she owns .. 1 in upstate NY where she went every year when school let out and now longer there since she retired . the other home here in Florida , works on call at a Publix as a cashier .. pretty much on call means full time lol . Then she knits clack clack clack faster than I can type ,Aran knit sweaters to sell , copper custom jewelry and assorted other crafts . Not sure I want to see here at 90 lol she’ll probably be climbing Mount Everest and hang gliding off the summit .

some asshole hit and ran her Vette a few months ago in a parking lot while she was shopping.. fixed now ..
 

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8HP70 is the standard auto behind the 5.7 & 6.4/392 hemis. Latest version stock 392 is rated 485hp/475tq; that puts it 50 lb-ft shy of the Ram Viper engine, though the HP70's have been fine behind somewhat modified 392's. They can also be built up fairly easy (but probably not cheaply). There is a 2004 quad cab running around with a 6.1 based 392 stroker (run by a Holley standalone that is somehow talking to the factory gauges) and an 8HP70.
The 8HP90 is the stock trans behind all Hellcat, Redeye & Demon engines. Lowest power Hellcat is 707hp/650tq; think we're good there lol. Redeyes are 797hp/707tq, Demons came in 2 flavors of 840hp/770tq and now 1025hp/945tq.
Something to note, the 1320 Scat Pack and Demon transmissions come with factory trans brakes that can be activated in another vehicle.

I’ll take the scat pack 1320 Alex lol .. all new info for me , thanks ..
 
She’s slowed down some now .. she only mows her 3 acre property , plants all flowers every year , mulches and paints both homes she owns .. 1 in upstate NY where she went every year when school let out and now longer there since she retired . the other home here in Florida , works on call at a Publix as a cashier .. pretty much on call means full time lol . Then she knits clack clack clack faster than I can type ,Aran knit sweaters to sell , copper custom jewelry and assorted other crafts . Not sure I want to see here at 90 lol she’ll probably be climbing Mount Everest and hang gliding off the summit .

some asshole hit and ran her Vette a few months ago in a parking lot while she was shopping.. fixed now ..
So what does she do in her spare time? :eek:
 
:cool: That is a busy lady! It sure helps with boredom when you're busy. I'm glad when people can get the things accomplished in life that makes them happy. Good on her for reals :cool:
 
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