273 performance

[pstone]

I am loking for info on 273 performance. I read a article in a old copy of Mopar Muscle, about small blocks, it stated that a 360 crank could be turned down to fitted the 273 hence making it a 304 stroker motor. I was wondering if anyone has done this or knows of some info on doing this. I have a V-100 2dr Valiant, with a 273 3spd. I would like to keep the motor add a 4spd and 83/4 axle. I know that I could use a 360, but I want to be different. Any info would be appreciated.

[Billydelrio]

That combination will take a custom piston. C&A will make them for $108 each. You can also use a 4" crank to get 330 cubic inches for just $200 more. The problem with the 273 is obtaining pistons at a resonable price. $864 was a bit rich for me, so I am going to replace my 273 with a larger engine in the spring.

Billy

[morrisbrw]

Dear pstone the 273 is a good engine with a standard stroke of 3.31. Buy some heads from Aeroheads for a 318 that has 1.88 intake and1.60 exhaust valves. These heads come with new valve springs, new ss valves and flow not too bad. The springs are for a .509 lift. Ready to go out of the box. Use the 273 high performance pistons (factory). They will give you a 10-1 compression ratio. Get a cam and lifter kit from comp cams. A good one would be the extreme energy 474 hyd. This will give it a good lick at idle and will make it zip pretty well down the road.

[morrisbrw]

Pstone the474 cam is incorrect it should be a274.

[DartGT66]

Where can you obtain the factory HP pistons?

[pishta]

That is the $800 dollar question......custom or nothing. There is a website that has a sign up form for a group casting from a major piston manufacturer. If they get enouigh interest theyll cast/forge a lot.

[Karl43]

Keep in mind if you go with this 273 stroker, how are you going to flow through the heads? Morrisbrw recommends 1.88" valves which will help the combination breathe. To do this you will have to notch the bores for clearance with the larger valve.

This is why it is easier to hop up a 318 than a 273. You can put 2.02 valves on a 318 and not have to notch the bores like a 273. A 318 block will bolt in in place of a 273. Everyone will believe it is a 273 if you tell them (non Mopar freaks don't know the difference). Throw in a set of Rhoades variable duration lifters and everyone will believe it is a solid lifter 273!

[pstone]

I greatly appreciate all the info that everyone has offered . I weighed my options and I think for the cost of building a 273 I can purchase a 360/380 crate motor from ma mopar, and come out alot happier. I figure with the 360 a 4spd and a 83/4 with good gears in a car that weighs 2950lbs, that it ought to motivate fast enough to give the brand x cars a run for thier money. Maybe I add turbo or supercharger. Again thank you for all the info. pstone