i may be doing an ls3 build in the future, and plan on doing h,c,i and full exhaust to her. If i did the exact same mods to a 418 ls3 stroker, how much more gas will i use...will it be like a 1-2 mpg difference on the highway?

 

Lol if your building a 418 with heads,cam,long tubes and an intake, is gas mileage a concern?
If it is just keep your 346 and build it, my old ls1 setup with tfs 220 heads,Lt's,VRX5 cam and a FAST 90 only gave me 12mpg city with 456 hp and 400 tq. It is still a weekend car so not too concerned about mpg.

 

HEY!!......lol.....idk ive seen built ls1s seeing 18-22 highway so something mighta been up with yours...maybe your tune was more for performance idk

 

o wait that wasd city....so you shoulda been seeing about that....nah i mean unless im wrong here, i think a 376 with big cam, heads, and intake should still see like 17-21 highway i would think

 

Lol just get it and MPG be damned!!

 

fine i will

 

You're gonna spend 5,6,7,8000 on an engine and sweat about 20$ a week more in gas?

 

I average about 15mpg driving to and from work. Mix of highway, local roads and stinking bumper to bumper traffic. Cruising on trips, etc - I average about 21-22MPG. Mine is a very mild build with a very small cam for a 427.

I can get it down to single digits very easily...

 

LOL. When I picked mine up Saturday it was showing 6.7 mpg average.

 

I know I don't have a stroker and turbo's are a lot more efficient in using exhaust gas you NA guys just waste

I can get 17-18 in town out of boost and 24-25 on the highway with the old 3.08's. Now that would drop to 12-13 and 19-20 if I get into boost frequently. With the 3.55's I expect it to drop to 22-23 on the highway and 16-17 in town, but I have 3 cars so it's not a DD by any means!

 

Was that stopped dead on Rt 64 or when you were trying to make up time.

 

I have a small cam 427 in my 02 6-speed C5. I get 18ish in normal driving and 26-27 on the highway.

 

Our 600+ rwhp GTO gets 15 mpg hwy, but I only drive it about 1,500 miles a year, so who cares. Our 02 z28 stock ls1 6sp gets 27 mpg hwy.

 

Amen if you're worried about gas mileage buy a Prius.

 

how dare you,,,,,,,

 

If you can pay for the storker engine - you can pay for the gas.

 

Did I offend you? Don't tell me you already own a Prius?

 

The next one who mentions a P**us gets all their text turned pink permanently.

 

sounds more like he owns a 88 honda

 

my 404 /w torquer 3/ls6 intake/241 heads got 14/24 highway m6, 3.42s. Not too shabby.

I got a sick new topend, i dont think it changed all that much to be honest.