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Mpg for my 87
- Thread starter agb1976
- Start date
Reinovator
Member
Is this fuel injected? If so I would think a good tune up may help a little but 454's stock are not known for their mileage with out some changes.
If a carburetor try getting the carb, rebuilt. or a new carb.
It sounds like this was set up for towing, which won't change your mileage much. The 454 with a th400 behind it is a Power house which can take a lot of abuse, and keep your speed up in traffic, on hills etc, when towing or hauling a heavy load.
A set of headers can also help 5 to 15% increase in economy.
a little deeper work would be a good Cam, and a few more bucks a new chip set up in the computer.
A 4speed auto would help also may be a 700r4
The best I've seen is about 15 mpg, average about 10 to 12 mpg with a little work.
Oh, I have seen a blown 454 get 18 mpg on the high way, but 4 grand to get 18 mpg, your choice, this was also a muncie 4speed in a 1/2 ton.
You have a great power house set up, check around some more I 'm sure there are more tricks which can help
If a carburetor try getting the carb, rebuilt. or a new carb.
It sounds like this was set up for towing, which won't change your mileage much. The 454 with a th400 behind it is a Power house which can take a lot of abuse, and keep your speed up in traffic, on hills etc, when towing or hauling a heavy load.
A set of headers can also help 5 to 15% increase in economy.
a little deeper work would be a good Cam, and a few more bucks a new chip set up in the computer.
A 4speed auto would help also may be a 700r4
The best I've seen is about 15 mpg, average about 10 to 12 mpg with a little work.
Oh, I have seen a blown 454 get 18 mpg on the high way, but 4 grand to get 18 mpg, your choice, this was also a muncie 4speed in a 1/2 ton.
You have a great power house set up, check around some more I 'm sure there are more tricks which can help
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Is this fuel injected? If so I would think a good tune up may help a little but 454's stock are not known for their mileage with out some changes
YES this is tbi injected. I will be doing a tune up real soon. I would love to put the 700r4 behind but the cost up front I can't come up with.
YES this is tbi injected. I will be doing a tune up real soon. I would love to put the 700r4 behind but the cost up front I can't come up with.
So I got new wires and plugs put in except the back plug on the drivers side. Its pretty tight in there. I tried getting it from the fender well as well with no luck. Had a check engine light after all the wires and plugs were changed. It was running like a tank, sounding like a real big block and I could smell the dollars comin out the tail pipe. Turned out to be the vacuum line tore from the map sensor. Its running a lot smoother now.
Reinovator
Member
Sorry I took so long getting back to you I had a death in the family, had to go out of town. your vacuum line situation should improve your mileage a lot.
I wish I new more tricks, I'm more experienced with 455 olds big blocks.The basics are the same until you get into cam changing, porting, carb's headers, etc.
good luck
my 305 is falling on it's face right now when I open up the secondaries, I've got 5 mid 70's rotten chester quadra flushes and one I hope will do the trick.
I may have to re-curve the distributor. Or maybe just take a breath and start from the basics.
Re-timing using vacuum gauges. That's why I bought that, dah.
if that dosen't work, re jet or rebuild another carb.
Check for leaks,
Check for cam ware.
You get the picture, If all else fails read the instructions.
I wish I new more tricks, I'm more experienced with 455 olds big blocks.The basics are the same until you get into cam changing, porting, carb's headers, etc.
good luck
my 305 is falling on it's face right now when I open up the secondaries, I've got 5 mid 70's rotten chester quadra flushes and one I hope will do the trick.
I may have to re-curve the distributor. Or maybe just take a breath and start from the basics.
Re-timing using vacuum gauges. That's why I bought that, dah.
if that dosen't work, re jet or rebuild another carb.
Check for leaks,
Check for cam ware.
You get the picture, If all else fails read the instructions.