New & looking for help/opinions

[97 heavychevy]

Well, 400 HP, and 410 gears, that's asking for bad MPGs, but let me make you feel a little better. I just bought a 1979, Corvette. It has the OE L82, 350 in it, with cam, Edelbrock heads, Edelbrock intake, long tube headers, Holley sniper EFI, Holley distributor, roller rockers, and I admit, that it is running a little rich rite now, but I filled up last night, and I'm getting 6.7 MPG. Keep in mind that it has its OE Muncie 4 speed transmission, so there's no OD, but 6.7, is bad, no matter how you slice it. My 97 Silverado, only gets between 10 and 11MPG in town. It is the Vortec 350, with 373s and an Eaton truetrac. It has shorty headers, cats deleted, tuned with a jet programmer set to max performance, electric fans, big 3 upgrade, but really it has 2 extra grounds, so the big5 up grade. And a ton of mods besides those. The internals of the engine, are OE though. If you want good MPGs, one of the biggest things is small tire size, ( like the OE 15 inch tires), and rear end gears. If you can get the RPMs down, that will give you better MPGs, but you will sacrifice that put you back in the seat performance, and you will loose pulling power with a higher gear ratio. 273s will give you grate MPG, but your truck will be a dog.

That Corvette sounds like it gets smiles per mile instead of miles per gallon, still worth it! lol

 

[97 heavychevy]

I think 400hp with quick bolt one is a stretch. Maybe with a supercharger,turbo and nitrous, maybe?
That power level will definitely need a new cam plus heads, and fuel upgrades like intake, bigger injectors and tuning for sure.
Sounds like a fun project for a nice looking rig. Always wanted one .... someday. Lol

Yeah 400hp might be a little over ambitious. I know goal #1 is to get this thing going again, tore it down a few years ago and sat since. Tired of people stopping by asking to buy it so I got to get it moving again. Heads are currently pulled off, so was wanting to upgrade anything while I'm at this point. Bare minimum will be e-fans, 411 pcm swap and injectors though.

 

[kennythewelder]

That Corvette sounds like it gets smiles per mile instead of miles per gallon, still worth it! lol

Yeah, the Vette is a blast to drive and a beast. A friend has a 1980, ( mine is a 1979) with the same heads, and EFI from a 90s Vette. I think he has a little bigger cam, but I know we are close on HP. He just dynoed his car, and is at 410 HP, at the wheels. That should be maybe 475 at the crank. The way mine runs, it is somewhere in that range.

 

[618 Syndicate]

Heads, cam, headers, and a tune will get you 400 hp.

 

[HotWheelsBurban]

I have a similar truck; '97 C3500 crew cab long bed, SRW, with the 5.7, 4L80E and 4.10s. It gets 10ish mpg around Houston, very little freeway driving, and 11-11 1/2 loaded and towing a loaded utility trailer. Probably at capacity in the truck, with 3 people and our gear for a long weekend swap meet trip, tables and parts in the bed, and the trailer and load were probably a ton and a half at least. Unloaded, just 3 people and some stuff in the rest of the back seat, got 13-14 mpg. The 350 is probably less thirsty than the 454, but you're still moving a lot of truck around. Mine is 5500# according to the title. A dually has to be a bit more.

 

[97 heavychevy]

Heads, cam, headers, and a tune will get you 400 hp.

Heads, cam, headers, and a tune will get you 400 hp.

Any recommendations on heads or cam? Off the shelf cam or custom ground. Getting heads worked or new ones all together. And bonus question what's the go to for injectors on these L29's?

 

[618 Syndicate]

Any recommendations on heads or cam? Off the shelf cam or custom ground. Getting heads worked or new ones all together. And bonus question what's the go to for injectors on these L29's?

Depends on your budget. Google "454 top end kit" and you'll be presented with a ton of options.

5.0 motorsports injectors seem to be popular, search this site and you'll find what folks have used.

 

[Erik the Awful]

I recently bought my son a '94 RCLB with a 305 to replace his dead '06 Crown Vic. The transmission isn't in the best shape, so he has to be gentle with the gas pedal. He says it's getting nearly Crown Vic gas mileage (22 mpg), but I think he's being optimistic.

That's the only way you're going to get good gas mileage. Get a V6 or a 305 and drive it like grandma. No 400 hp, no fun, but cheap.