removing emissions lines from a pontiac 301 for more power.

[Big D]

hi i'm new to this forum and was wondering if there's a site on which emission lines to remove and what to block off to get more power out of the 301. Its a 80' grand prix.

Daryl

 

[85 Cutlass Brougham]

There will be very little improvement from removing the emissions equipment. Removing the catalyst will provide the most improvement, but that is more likely because the old one is probably plugged than the engine needs much more air flow than stock. The best bang for the buck improvement would be better gearing, with the 3.23 axle being the cheapest to find in a junkyard for under $100. You probably have a 2.41 or 2.29 axle now and there will be a big improvement if you put in shorter gears. Beyond that, I would look for a real Pontiac engine like a 400 or even a 350 as they will give the best improvement for the least amount of investment. Get a running engine and just drop it in with new gaskets and a new timing chain and you may be able to do it for under $500-perhaps as little as $250. I just came across either a 326, 389 or 421 in a old 1963 or 64 Grand Prix at my local U pull it and the engine was $125. (Anyone know how to tell the difference without taking it apart?) I have also found 400's in Trans Ams and even the occasional 455.

 

[KrisW]

Hey 85, where's the local U-pull it wrecking yard???

 

[KrisW]

Oh, and yeah, Remove 301, replace with any real Pontiac V8...

That's the only reliable way to improve power on a 301. If you want, you can start with headers and good exhaust because all of that stuff will also bolt to the real Pontiac engine later on.

Good luck!

 

[85 Cutlass Brougham]

LKQ/Copher's. I go to the one out in Riverview (off Causeway blvd), the one in Clearwater ( by St Pete/Clwtr arpt.) and the one in Kenneth City ( St Pete/Pinellas Park area). I also go to the Big Three U pull it around the corner from the Clearwater LKQ. The GP was in the Clearwater LKQ and the engine was complete down to it's original air cleaner and AFB carb.

 

[85 Cutlass Brougham]

Oh, and yeah, Remove 301, replace with any real Pontiac V8...

That's the only reliable way to improve power on a 301. If you want, you can start with headers and good exhaust because all of that stuff will also bolt to the real Pontiac engine later on.

Good luck!

Doesn't the 301 use a unique intake and header flange? Or is the the Olds 260/307?

 

[KrisW]

The olds engines have smaller ports but everything still interchanges.

The 301/265 Pontiac are the strange ones. The only things that can interchange are the headers and camshaft. Nothing else, including block hardware.

 

[atozracing]

There are alot of things you can do to the 301 to make power!!! My 301 in the firebird runs 12.31 @ 107.75 and weighs 3545 with me in it. I added 165 lbs to go down a class and it still goes 12.50 @ 106.83 and that is with STOCK exhaust manifolds !!!!! you have to understand the limitations of the engine (this goes for all of them) and build the most power within those confines. If the engine doesn't rev much past 5700 making power, no use putting a tunnel ram manifold and dual dominators on it unless it is all for show. I have a GTO that has a 455 smog motor, will pass AZ emissions, can use pump gas, and still runs in the 12.70 range in 110 heat here in Arizona, and yes, I could drive it anywhere. It is all about thinking practically. Bigger isn't always better, ie. cam, compression, headers, etc.

 

[KrisW]

I made serious power with a 301 as well, right up until I broke the block!! That's right, the block! I didn't throw a rod or break the crank, I broke the block down in the main webbing and then the crank jammed and well....

It was great until that happened...

I'm sure you can get into the 12's with it, it's just that you can't drive it hard over and over and expect it to last. The rest of the Pontiac family is pretty stout as far as block castings go and will take a lot more abuse.

 

[shotgun]

I have played a bit with the red headed step child of the Pontiac family.
The 301 is a short deck block,1" I believe.
Intake is 301/265 only.
Cam,timing set,timing cover,water pump,fuel pump,dist., exhaust manifolds.valve covers,oil pan, motor mounts(late block) bolt up.
The front acc.with brackets alt,a/c,pwr steering will all work with minor drilling of the brackets.

This is what I did to my driver 79 Grand Prix.

4 barrel carb and manifold from a Firebird
K&N filter
"High Output" HEI with light springs
Ran cold air tube to the bumper
Cat back using 1/2 Monte SS exhaust
replaced the 2.14,yes 2.14 gears,with 2.92 I think


Made for a nice driver that was ,at the most, peppy.MPG improved with the mods!

You could block off the EGR to keep the manifold cooler.

Exhaust manifolds off the a 350/455 do bolt up,I have done it,but there is not much to gain there.

It is what it is.Never designed to be a performance motor.

If your long term is higher performance,do what the guys said above,make improvements that can be transfered to another motor later.

We did a mild 350 that went high 13z on the cheap in a similar weight to your GP.
With Pontiac's it's all about the torque.