305 to 454

[gto109]

I'm thinking about getting a 454 to replace my 305.  would i be able to find an adapter plate to bolt the 700r4 to the 454?  besides motor mounts what else would i need?

[zieg85]

I'm thinking about getting a 454 to replace my 305.  would i be able to find an adapter plate to bolt the 700r4 to the 454?  besides motor mounts what else would i need?

No adapter plate needed, motor mounts are the same as far as I know...  It is near a plug and play conversion..

[firefighter]

Motor mounts should be the same.
I swapped a 350 for a 454 in my 1978 and it was a direct fit with the TH350.
You gotta love the big blocks.

[gto109]

Thank you.  This is my first chevy truck.  I've dealt mostly with Pontiac & Ford. 

[Engineer]

The 454 takes a different clam shell (engine side mount) than the small block. Rubber (frame side) mounts are pretty much the same, even though some books call for different parts.

The small block clam shell will work on the 454, the only problem being that the factory 7 blade fan for the 454 may rub the bottom of the factory fan shroud for the 454's factory 4 core radiator. BTDT.

Chevy trucks are like Lego blocks........very interchangeable. After a Chevy or two, you'll want to throw rocks at every Ford you see from now on.

Edit: The brackets that hold the power steering pump, and alternator are different. These pop up on eBay all the time. The brackets for the A/C compressor are a little more difficult to snare however.

[gto109]

So I'm going to need a different radiator then.  i believe it has the seventeen belt set up on it now.  My buddy said that I should just go with a 350. That a 94 454 is a gutless gas hog.  What is you guys opion.

[lukieg]

 Honestly bud.. I just swapped out a 305 for a 366 ... im swapping back to a 305... im netting at the very best 9 mpg.. when its cold (winter) and im running it around... until warm.. which takes a solid 10 min... about 3 mpg.. and 10 mpg driving 90 km/h on the highway.... go with a decent 350.. i wish i would have. The big block sounds great.. headers and dual thrush. Lots of torque.. pulls very nice until 5000 (was much lower bfore cam swap) but its not worth the mileage.

[bake74]

     As lukieg said, if you are worried about mileage at all, I would advise against the big block.  Now if you need to tow or you are building for a monster engine, then you should not be worried about milage.

[gto109]

Its my work truck.  i haul firewood and use it to pull  trailers

[bake74]

Its my work truck.  i haul firewood and use it to pull  trailers

     The truck I use to drive to work and back home in, is a 2000 Gmc sierra crew cab z71 with the 454 o/d 4 speed auto and full floater rear end.  I use this truck to tow with and let me tell you, it tows, love the power and torque of the 454. (My work truck is a 2003 ford f350 with a utility bed and racks on it, and my Gmc will tow just as good if not better then the ford)
     Now I get about 14.5 around town, 16 or so on the hight way (empty), and if towing say the 30 ft. 5th wheel, it gets about 10 mpg.  But I did not want or get it for mpg.  I needed to tow stuff and I love to drive trucks. (not a big fan of driving cars)

[gto109]

The camper is a 70's model i use and it weighs around 3 ton if not more.  every time i take it some where i use my brothers diesel.  to heavy for my truck.  when we go and get firewood we make mine work.  we fill both truck beds my 10 ft trailer and his 16 ft trailer. 

[Blazin]

Only thing a 366 is good for is keepin your boat from floating around the lake when your not using it!
If you work your truck there is nothing better than a 454. A good running 454 should give half way decent millage when your not working it if you drive it respectably. My 86 K30 dump unloaded and not driving it like I stole it will give me about 14 MPG. It has a mild cam, and aluminum intake.

[gto109]

Is a 366 a 6.2?  if so we have no complaints about it.  it has done every thing we had wanted it. to do with no problem other then not get stuck because its 2 wheel drive.

[Blazin]

366 is a destroked big block. They are gutless wonder gas guzzelers!