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oldskool · 01-19-2015, 05:44 PM

I do like the idea of racing with leaf springs. They are just so much simpler to deal with. So that leaves a choice between a Bird or a Vent. I really prefer a Bird. But I like Vents OK too. And I figure a decent Vent body will be a bit cheaper than a decent Bird body.

So, if I don't use my '74, for the reasons mentioned, lets explore the other possibilities. The 350P was not used in a '71 Vent. It was used in '72, but is factored at 250hp. So that's no good. But in '73, it was used and is factored at 210hp. Also, the '73 model is the last year that NHRA allows 350P pistons, with valve reliefs, according to the info on the link below. The '74-'77 350 pistons are absolutely flat--no reliefs.

http://www.classracerinfo.com/Engine...px?ENGINE=2071

The old TRW forged piston # L2339F is legal for the '68-'73 350P. They quit making these a long while back. But you can occasionally run across an NOS set. I have 2 sets. One in the box and one in the 350P shortblock that came out of the 350HO Tempest I mentioned. The oil was milky in it, and I had no use for it at the time. So we never even tried to find out how the water was getting into the oil. It and the other 350 pistons are still over at my engine guy's place. There is also one high dollar piston that was approved over a year ago but is not on the list at the above link. It's a CP brand # P5-CP. This site shows that both it and the TRW 2339 are legal thru '74. So there is conflicting info there, between the 2 sites. But since the site linked below is an official NHRA site, I'll go by it. So, according to it, the '74 models can use any of the approved pistons for all years of the 350P, from '68 thru '77. This info can be found on the bottom of page 60 and the top of page 61 at the link below.

http://www.nhra.com/userfiles/file/N...edProducts.pdf

The 350HO shortblock I mentioned just has stock, cast rods in it. But in a 350, they should be good to at least 6200-6500rpm. I don't figure a 2-barrel 350 will pull any higher than that. I don't have any #46 heads to put on it. But I do have a good set of 6x heads I could use on it for testing purposes. I could find out if I can get a 2-barrel 350 to run under, without buying a set of cores and paying for the head work.

My engine guy has a 350 block with 8 sleeves in it, that he was going to use for a serious dirt track project. But all the tracks in our area shut down. So, I could use my NOS TRW pistons and his 350 block, and build up a strong 350 shortblock. Hey, I'm just sorta thinkin out loud. I reckin that's the way a lot of low buck guys do it--think of all the parts you have available and figure what you can put together.

I've got a 2-barrel on a '71 455, that came out of a Safari wagon. I wonder if that would pass tech on a '73-'74 350 Vent ? By the way, this same engine is legal in a '73-'74 Bird and lots of other models.

Any more comments on the possibility of running under with a '73-'74 350 2-barrel engine ?

01-19-2015, 05:44 PM	#54
oldskool VIP Member Join Date: Dec 2014 Location: The Land of Bayous, Boudin & Crawfish Posts: 1,668 Likes: 223 Liked 747 Times in 362 Posts	Re: Ol' Fart's Firebird Fantasy I do like the idea of racing with leaf springs. They are just so much simpler to deal with. So that leaves a choice between a Bird or a Vent. I really prefer a Bird. But I like Vents OK too. And I figure a decent Vent body will be a bit cheaper than a decent Bird body. So, if I don't use my '74, for the reasons mentioned, lets explore the other possibilities. The 350P was not used in a '71 Vent. It was used in '72, but is factored at 250hp. So that's no good. But in '73, it was used and is factored at 210hp. Also, the '73 model is the last year that NHRA allows 350P pistons, with valve reliefs, according to the info on the link below. The '74-'77 350 pistons are absolutely flat--no reliefs. http://www.classracerinfo.com/Engine...px?ENGINE=2071 The old TRW forged piston # L2339F is legal for the '68-'73 350P. They quit making these a long while back. But you can occasionally run across an NOS set. I have 2 sets. One in the box and one in the 350P shortblock that came out of the 350HO Tempest I mentioned. The oil was milky in it, and I had no use for it at the time. So we never even tried to find out how the water was getting into the oil. It and the other 350 pistons are still over at my engine guy's place. There is also one high dollar piston that was approved over a year ago but is not on the list at the above link. It's a CP brand # P5-CP. This site shows that both it and the TRW 2339 are legal thru '74. So there is conflicting info there, between the 2 sites. But since the site linked below is an official NHRA site, I'll go by it. So, according to it, the '74 models can use any of the approved pistons for all years of the 350P, from '68 thru '77. This info can be found on the bottom of page 60 and the top of page 61 at the link below. http://www.nhra.com/userfiles/file/N...edProducts.pdf The 350HO shortblock I mentioned just has stock, cast rods in it. But in a 350, they should be good to at least 6200-6500rpm. I don't figure a 2-barrel 350 will pull any higher than that. I don't have any #46 heads to put on it. But I do have a good set of 6x heads I could use on it for testing purposes. I could find out if I can get a 2-barrel 350 to run under, without buying a set of cores and paying for the head work. My engine guy has a 350 block with 8 sleeves in it, that he was going to use for a serious dirt track project. But all the tracks in our area shut down. So, I could use my NOS TRW pistons and his 350 block, and build up a strong 350 shortblock. Hey, I'm just sorta thinkin out loud. I reckin that's the way a lot of low buck guys do it--think of all the parts you have available and figure what you can put together. I've got a 2-barrel on a '71 455, that came out of a Safari wagon. I wonder if that would pass tech on a '73-'74 350 Vent ? By the way, this same engine is legal in a '73-'74 Bird and lots of other models. Any more comments on the possibility of running under with a '73-'74 350 2-barrel engine ? Last edited by oldskool; 01-19-2015 at 06:45 PM.