[74TA455]

Alright guys. Having a 455 is getting old.. real fast...

I know im not the only person to complain, but gas prices at 8 mpg are just not worth it. Plus it overheats and just isn't realiable.

Im thinking 350 Pontiac with TH400 3:08 Gears

Im hoping to average 17 - 20 mpg with mostly highway, some city driving

Guys any help would be appreciated. You guys are familiar with 74's and what can be done. I might even go with one of those fiberglass front bumpers to lighten it up.

What do you think I should do for heads?
Intake?
Cam?
I know a Quadrajet Carb would be more efficient than a 2 barrel, but early or later style? size?

I dont want a radical motor. Just something efficient!!

thankyou

[opnwide]

If you want efficiency, drop in a 231 turbo buick. If you're going to wuss out, at least have some style. They DID put that engine in a TA if you remember. They never put a pontiac 350 in a TA.

[1971WARBIRD]

my 71 HO TA 4 speed would get 16 mpg on the interstate if i kept my foot out of it.
+.030 455,HO heads-intake-carb,crane 218-230/450-465,hooker headers,3.31 gears.

my 73 TA would get 13 mpg after it's rebuild.
=.030 455,small chamber 4X heads,edelbrock performer intake,73 Qjet,RAIII exhaust manifolds,2802 summit cam,L88 converter,3.08 gears.after cleaning the block,heads and cooling system it would barely get over 170.lots of junk in those cooling passages.

i have a 79 10th in the paint shop now with a 455 waiting to see how it does.
+.030 455,large chamber 6X heads,72 cast iron intake 72 qjet,2.5 exhaust,2801 summit cam,L88 converter,2.73 gears.
having someone like Cliff dial in your qjet can make all the difference in the world.

[74TA455]

Thats true a 350 never went into a TA, but I am up for anything that bolts up to my TH400. That is reasonably easy to find, and simple to put in.... Just looking to get 15 mpg city...

[Larry Navarro]

Whoa!!!......Step back!
You better talk to Cliff Ruggles before throwing out that 455. Even with his high performance setup I think he was getting at least 15mpg with his Q-jet.

[74TA455]

Do you know his user name? I did some reading and heard that cliff rebuilds carbs that perform amazing I believe?

[SD73]

Hmmm, given any thought to an overdrive tranny?

[74TA455]

I was thinking a 200R4 but dont think I would see that kind of results still from a 455. Super carb + OD tranny + 455 = 15 mpg. What do you guys think?

Which cars had a B.O.P. OD 200r4 tranny? Maybe I could find one at a junkyard.

[Held for Ransom]

Originally Posted by 74TA455

Do you know his user name? I did some reading and heard that cliff rebuilds carbs that perform amazing I believe?

Cliff R

[Tonyqt]

My 74 455 gets 16+ on the highway and around 12 around town. I don't race it at every stop light but I still have my fun with it. It has 3:08 gears in the rear so it doesn't rev to high when doing 70. As far as over heating. My car runs cool all the time. Even when it's in the high 90's. There is no reason your car should over heat. Something must need attention. It still has it's original numbers matching 455 and has never let me down. I drove it 600 miles each way to the Nat's in Dayton last year and only used a quart of oil. Averaged 16.4 miles a gallon for the weekend. I don't think you will get much better gas mileage from a 350 as our cars are HEAVY! The torque from the 455 needs less gas to get the car moving then the 350. I would think twice about changing to a 350 and look into why you are getting such bad gas mileage and over heating. You'll be surprised at what a well set up car can do.

[se428bandit]

Why not just rebuild the 455,change to a 2:41/2:56 gear out of 75 or later T/A.A 350 is not going to get you better gas mileage alone,i would also contact Cliff maybe he could help you on the carb.On the over heating,try 1st changing the themostat [if that don't work] then try the water pump and check the plate in between the water and and the housing,my had a holes in it causing the motor to run a little warm.

[loggerhead]

To see what's possible with a 455(462), do a search on "TKO600 5-Speed MPG".
The numbers posted are straight "out and back" highway runs. Real world MPG mostly
highway with some in town driving without "getting on it" is around 18 MPG.

[BAD455TA]

I know this is an old thread but !!!!!!!!!!!!!STOP!!!!!!!!!!!!!! Don't to it!!!!!!!! If you don't care about performance you can do so many things to a 455 that will make it streetable with good mileage. If you don't want to do the carb work yourself take it to someone who will. Quad's are great efficient carbs that can be tuned to be street/race ready.

IMO if your worried about gas mileage, your driving the wrong car. You can save a ton of money by just changing the cam and getting a good tuned carb and maybe (if needed) swapping the gears. the will cost you much less money and save you a lot of time. Plus, a T/A without a 455 is like a pool without water; it's not even worth it.

[74TA455]

Well guys im keepiung the 455. Looks like it took alot of advice (screaming) given to me to make me think bout it. bad455. Im actually in Arlington. You have probably seen me or know some pontiac people I know. You see guys the reason Im wanting gas mileage is because im a 18 year old college student. This car was my first car and I quickly acquired a efficient S-10 within the first year of driving it. I talked to a few people and they believe that 19 mpg (MOSTLY HIGHWAY) is POSSIBLE! I WILL BEGIN THE CHANGES AND I WILL KEEP YOU INFORMED ON HOW WELL I MANAGE TO DO.

[BAD455TA]

That's what I'm talkin about