2007 5.3 (with displacment on demand) swap?

[NorCalKid]

Anyone swaped in a 5.3? I was reading about the 2007's, with that displacment on demand, and they put out 320 hp at 5,300 rpm and 340 lb-ft of torque at 4,200 rpm. They say it gets 21 mpg on the highway it wouldnt be close to that in a big old blazer or truck but it cant get much worse then the under 10 I get now. What would be needed to swap one of these into a k-series? or would it even be worth it? What about bolting it to a sm465?
-Thanks

 

[01maroonz71]

the tricky part would be getting your hands on one of these DOD 5.3 motors. maybe out of a wrecked 2007 or something like that. im 99% sure that the granny trans won't work. you'd be better off keeping the stocker out of the 2007. it would be much better, and since you need the comp, and harness, it wouldn't be much harder either. motor mounts will have to be built, but other than that...not a bad idea. oh yeah, your trucks a 73, so you'd need a new intake fuel pump to feed the EFI.

 

[dhcomp]

and its fly by wire, so you have to address that. The dude on here that does all the gen IV swaps would be able to help you i bet.....i think the best solution he came up with was to mod hte fly by wire and keep the electronic gas pedal....

 

[87BrnRsd]

It would be a pretty tough job I think. You would need the wiring harness and computer. I doubt anyone makes an adapter for your transmission and i also doubt anyone is gonna make those motor mounts. It would probably be much easier to swap in an older gm diesel if you want more mpg. Plus, from what I have heard, the 5.3 motor is designed to rev high to make power. They are built to handle the high rev's that they need to create power, but you really dont want that in an offroad truck. You want low rpm power.
-Harrison

 

[guz71]

Yeah my tahoe had the 5.3 and it like to be wound up. With the aerodynamics of a brick and turning over 35's, I doubt it would ever go in to 4cyl mode except for at idle. From people I have talked to, say they only go into 4cyl mode when at idle, going down a hill, or crusing on a flat road under 50 or so. The overdrive transmission would probably help out the most if your wanting to gain some economy on the highway.

 

[dhcomp]

the way ppl are making the 5.3's work well is with a performance tune. It eliminates the torque management that really limits these motors. I don't know if anyone has a performance tune out there that works with DoD.

 

[NorCalKid]

Sounds like it would be a hassle to work it all out. Maybe by the time I can afford to buy a new engine there will be an easy way to do it, if not maybe a desiel is the way to go.

Thanks for the info

 

[guz71]

I had a custom tune on mine and it did a lot, but you could still tell it had torque managment. After the tune and 4.56's, I could barely get the tires to chirp off the line but once it got rolling it was like a bat out of hell all the way up to 60. It definately had some good power but it didnt get that great of gas mileage. With 35's and just a body lift, I was get 14-15 on the highway doing 75 and only about 11 in town driving conservatively. If I started romping on it would definately dip down below 10.

 

[SUPERSUB87]

We have a 2007 suburban. the DOD doesnt really help all that much unless you are on a slight downward incline or on a flat surface. living in the hill country. i constantly see the little indicator go from v8 to v4 and in less than a second back to v8. i tried being light on the pedal and not using cruise control, it helps a little but not much. as for the whole below 10 miles thing. why dont you just buy an efi kit from edelbrock to hook up. a lot easier and about $1600

 

[mello_yello]

it would be pretty cool, if you got the funds i say do it, or maybe you could buy some rice POS, get like 30 something MPG drive ur truck that gets about 10 mpg and it would even out, but save you some $$ maybe.

 

[SUPERSUB87]

or you could be really different and throw a supercharged vortec v6 in your blazer. dont really know what it would do. but you would be different. and you might save some gas. idk. just sounds funny.

 

[NorCalKid]

I was looking into the swap at school today and found a thread on pirate

http://www.pirate4x4.com/forum/showthread.php?t=569220

 

[resurrected_jimmy]

PM RyanB. he knows more about this swap than anyone around here. The companyhe works for does this stuff for a living

 

[vortec]

or you could be really different and throw a supercharged vortec v6 in your blazer. dont really know what it would do. but you would be different. and you might save some gas. idk. just sounds funny.

extremely doubtful you'd save any gas since forced induction requires additional fuel to correct the air/fuel ratio and compensate for the extra heat produced. but, it would be pretty dang cool. the 4.3 is ignored by too many, but is a solid engine to begin with, and can be modified in pretty much any way a 350 can. i won't say that it's a better engine to mod, but from what i've seen, the proportial power gains are slightly better on the 4.3 than the 350, when the same changes are made. lots of possible reasons for that. less rotating mass, less friction, less heat, fuel has less distance to travel in the intake manifold, etc.

 

[fabjunkie]

Yeah my tahoe had the 5.3 and it like to be wound up. With the aerodynamics of a brick and turning over 35's, I doubt it would ever go in to 4cyl mode except for at idle. From people I have talked to, say they only go into 4cyl mode when at idle, going down a hill, or crusing on a flat road under 50 or so. The overdrive transmission would probably help out the most if your wanting to gain some economy on the highway.

It stays in 8cyl mode at an idle, unless the comp just doesn't register it at an idle. On the highway, it does a decent job staying in 4cyl, until you hit a little more than the slightest incline. I get 18-23 on the highway, not going through hills. 30mpg or so just putting around town.

 

[Shawn]

It would be cheaper and lighter to get an LS1. I think the 5.3's still use iron blocks. In my Trans Am, I dyno'd 325hp bone stock at the wheels and got about 30mpg on the highway. Thats in a car of course but another option to look at. I'd try to find an 01 or 02 Fbody since they have the better heads and manifold and no EGR.

 

[vortec]

slight hijack here...

are the f-bodies really as unrealiable as the stats indicate? the reliability for the vette seems a whole lot better. my theory is that both are fine platforms, but that vettes are almost exclusively adult driven, and too many camaros and firebirds find their way into the hands of teenagers who romp on the gas every chance they get. i've been on a vette hunt lately, but haven't completely ruled out f-bodies.

reliabilty info is good to have, so maybe my hijack will help in the original subject some.

hijack off. that sounds a little offensive. i'll rephrase: Lift hijack. an homage to master blaster's "lift embargo" from mad max beyond thunderdome. who run barter town?

 

[guz71]

It stays in 8cyl mode at an idle, unless the comp just doesn't register it at an idle. On the highway, it does a decent job staying in 4cyl, until you hit a little more than the slightest incline. I get 18-23 on the highway, not going through hills. 30mpg or so just putting around town.

thats pretty impressive, i am jealous . I think with boxy lifted blazer and 35's, the engine would have a hard time staying in 4cyl mode while crusing down the highway though. Your truck definately has a lot less drag. Around town though would be interesting with correct gears.

 

[mr.smartass]

It would be cheaper and lighter to get an LS1. I think the 5.3's still use iron blocks. In my Trans Am, I dyno'd 325hp bone stock at the wheels and got about 30mpg on the highway. Thats in a car of course but another option to look at. I'd try to find an 01 or 02 Fbody since they have the better heads and manifold and no EGR.

Not only is that in a car... it's a car with a 6-speed...

 

[vortec]

Not only is that in a car... it's a car with a 6-speed...

6th gear is only .667:1, afaik. a 700r4/4l60(e) has a .70:1 4th gear. that's a pretty small difference.

but i do agree that a k5 will never get the mpg a vette is capable of. the 1-2 thousand lb difference and completely inferior aerodynamics of a k5 make that a llittle tough.