LS1 vs 1UZ. Fuel economy comparison

[Carwhisperer]

I'm gathering the parts to build a hot rod and I'm considering using a Chevy vortec 4.8 truck motor or a 1UZ from an early 90's LS400. I'm thinking I'd run an LS1 computer on the 4.8 vortec or just run an actual LS1. I do not want to open either motor up. I think they both put out about the same hp stock, 250ish, which will be just fine for the 2000 lb car. I do plan on commuting in this car sometimes (80 miles round trip) and I am concerned about fuel economy. According to the fueleconomy.gov website a LS400 gets 23 mpg highway while a late 90's camaro gets 27mpg with an LS1 and an automatic. A 4.8 Silverado gets 20mpg. I think the compression ratio is about the same on both engines. Any guesses as to which would be more efficient in the same chassis, 1UZ vs vortec/LS1? I'd probably just use the stock LS400 tranny. I am planning to use Lexus or Supra suspension for this project, btw, which is an argument for staying Toyota for power. The other argument for Toyota is it looks like I can get a motor for about half of what I'd spend on a Chevy.

 

[sideshow]

ive worked on plenty of 1uzs and ls1s
id go ls1 anyday as feels much more powerful in std form
and if its going into a big truck or u plan to tow with it the ls1 woul dhave more torque
my hilux with 1uz went good but as soon as i put my work gear in the back which might be 100kg then u could feel it
and in the usa every man and his dog has the ls1 tuning software to get more power just by reflashing the ecu
everyone on the toyota forums bags them out because they r still overhead rockers n pushrods but so far they still outperform the 1uz
if u want to do mods down the track say in afew years there is shitload more stuff available for the ls1

also dont trust the fuel economy stats from some websites
find a real person and ask them what fuel economy do u get
all the new car makers and sellers give their fuel economy stats normally for highway driving even then they exagerate the figures because they r all liars
ask someone local and also ask then fuel economy for normal everyday driving cause thats the real figure u want

 

[rising sun]

I reckon that the 1UZ will be more economical. In an LS400 I have regularly averaged 25 mpg without trying... The Chevy will probably be easier to wire,though.

 

[Smitherz]

Here's an easy answer. If you want more power then Chevy for sure. Better fuel economy? Both are good on fuel for V8's I think. You can't really use that to compare the engines as it's not really a deciding factor. They will be close in that respect. The UZ is much smoother running so if you want a really smooth running V8 then that's the way to go for you. Especially if you use the Lexus transmission.. smooth smooth smooth - perfect for hot rods and commuting.

I put the UZ in my offroad truck and it is pretty amazing. It cost me a lot more time and I'm sure it would have been cheaper to go the LS route. If I had to do it over again I would go LS engine. But for a hotrod car that you want a nice driveable V8 I think UZ.