Not likely in your application.The main reason for the change in the first place was overheating/cracking of the heads in heavily loaded[like truck and police car]applications.In your case there shouldn't be any issue at all as long as you build a good cooling system.I know that I wouldn't be worried about it.
'58 - 348 Tri Power
- Thread starter '37-4D
- Start date
Be advised that the stock three two setup with progressive linkage will need to be modified. That said there is a wealth of knowledge here to walk you through the steps. Good luck, I hope you stumble on a stock three two setup. My little 348 ran 14.6 @ 95 mph in a 4500 lb 60 Impala with the three two setup.
You might be able to start here......
https://sfbay.craigslist.org/eby/pts/6048319280.html
or
https://sacramento.craigslist.org/pts/6064823553.html
https://sfbay.craigslist.org/eby/pts/6048319280.html
or
https://sacramento.craigslist.org/pts/6064823553.html
'37-4D
Well Known Member
Thx. I saw one of these ads.
Blows that I'll be subject to 30% ish exchange rate and a shipping charge from hell....
That's a huge relief.
Are there particular casting numbers I should look out for with the tri intake when matching it to my 971 heads? or they are all good to go?
Thx Fathead. I hope so too. I have a link on a solid clean intake.
If a tri power carb set up can't be found, can Rochester 2 barrel carbs be equipped with a kit?
Sorry for the lack of knowledge here, I'm trying to learn so that I may be able to hold some form of a conversation with my shop guy.
Yes, there are sources for aftermarket parts to convert a 2GC Rochester carb to a three two setup.Thx. I saw one of these ads.
Blows that I'll be subject to 30% ish exchange rate and a shipping charge from hell....
That's a huge relief.
Are there particular casting numbers I should look out for with the tri intake when matching it to my 971 heads? or they are all good to go?
Thx Fathead. I hope so too. I have a link on a solid clean intake.
If a tri power carb set up can't be found, can Rochester 2 barrel carbs be equipped with a kit?
Sorry for the lack of knowledge here, I'm trying to learn so that I may be able to hold some form of a conversation with my shop guy.
Somewhere gathering dust in my shop I have a cast stock three two intake for the 348. The center dividers have been removed long ago by someone looking for performance gain. If I wanted to use this I would find a way to get dividers back in there. I would be willing to part with this intake if you can't find one.
Greg Reimer
Well Known Member
If you have a '58 block with no water cooling passages for the spark plugs, you have to either use the '58 only heads, or drill,tap,and plug the holes in the later heads. If you have a block with the water holes, you are OK to use the '59-65 heads. If you have a service replacement block with the provision for the hole,but no hole, it can be drilled OK. Use a 409 head gasket as a template to properly locate the hole. You can't use the '58 heads on a later block unless you plug the holes in the block. If you mismatch these parts, the result will be an exposed coolant passage that will pour water all over the place just beneath the spark plugs as you try to fill the radiator.Not a nice thing. The tri-power intake is an iron small port item, they never came on 409's new, I would grab an aluminum performance small port intake and a medium sized AFB and have at it. If the tri-power is your thing,remember that there are two sizes of Rochester 2 barrel. The '69-74 350 and 400 small blocks used a larger CFM carb, they are common and easy to find( unless you need a specific number)It would be possible to fab up three adapters and maybe make something work. 65 Pontiac tri-power set ups used a small center carb and large secondary carbs, the 66 on up set up used three large carbs. The optimal small port head was the 817 casting, found on 63-65 340 horse 409's. Not as pricey as 690 or 583 heads,either.I also heard that '58 blocks were rather thick,so rebuilding it wouldn't be a problem. Also, the non water passage '58 heads took a short spark plug like a 283 or 327. The long plug is for the 59-65 engines. If your heads have the long spark plug,and the piston doesn't destroy them, they're the later head with the cooling passage. I once was given a 348, upon disassembling it, somebody had put long plugs in a 58 head, the pistons were damaged, the electrodes were bent and broken, porcelain particles were in several cylinders, and the shells of the plugs were bent so the you couldn't remove them without cutting them off from the inside with a die grinder. Not a pretty scene.
Yes there are at least 2 kits to convert the early 2gc's for a tri power use.One such kit is from Speedway motors in Nebraska,the other from a guy named Charlie[I think] in Florida.Both have linkage availeable,and the complete kit thru Speedway is about 400.US dollars.The 3-2 manifolds for the 348 from 58-61 are all the same.
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'37-4D
Well Known Member
Thank you. I will keep you in mind. I believe I have found one!!!
Overwhelmed by the wealth of info I am getting here. Thanks a million guys!!! The picture is definitely much clearer.
I would have never known. It amazes me that they would try and sell you the wrong setup!!!
'37-4D
Well Known Member
Don, Thank you so much. You guys are truly GOLD!!!
I cannot wait to have the shop take the darn thing apart and tell me the bottom line here. Hopefully she's all good and just needs a little love, polish and a few new goodies to bring her back to life.
Your comment: "It amazes me that they would try and sell you the wrong setup!!!" kind of of sums up the buy-sell environments we have on the open Web these days (e.g., Craigslist, Ebay, etal). It's "buyer beware" on a good day...
So to be clear, it's not really "wrong", it's just that some collectors have a certain affliction to have what some refer to as "factory original", which means the dates on the carbs need to match the date on the intake, and so forth. Nothing wrong functionally with using "period correct" carbs that were not original to that intake (converted, etc.) as the will appear correct to the untrained eye.
That originality does affect value, however. A "date coded" tripower setup is worth more to the collector than one that uses non-original carbs. I would venture to say that a tripower intake with three "incorrect" carbs is valued at maybe $500 - $600 but the "correct" setup might be double or even triple that price to the right person.
Good luck with your build!
TomK
So to be clear, it's not really "wrong", it's just that some collectors have a certain affliction to have what some refer to as "factory original", which means the dates on the carbs need to match the date on the intake, and so forth. Nothing wrong functionally with using "period correct" carbs that were not original to that intake (converted, etc.) as the will appear correct to the untrained eye.
That originality does affect value, however. A "date coded" tripower setup is worth more to the collector than one that uses non-original carbs. I would venture to say that a tripower intake with three "incorrect" carbs is valued at maybe $500 - $600 but the "correct" setup might be double or even triple that price to the right person.
Good luck with your build!
TomK
'37-4D
Well Known Member
Roger that. I did experience this from a place I found on the web, to make me a complete set up period correct was like 4K!!!! that seemed crazy to me....
'37-4D
Well Known Member
Curious, how hard would it be to fix that intake and put the dividers back in? and would it really matter for me and my application?
Possible to get a pic?
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Well there weren't all that many to start with,maybe 10-15 percent of the 348's made had them.Factor in age,those ruined by incopatent "mechanics",and such.Even the small 2gc's are getting hard to find in rebuildable condition. Add to that the parts necessary to make them usable for a multi-carb set up will set you back about 400 dollars.If you do find some,just make certain that they haven't been "rebuilt" by any of the so called rebuilders as 50 percent of them were junk right out of the box.I observed back in the 70's that most of these were carbs that a good mechanic couldn't do anything with[sand holes,warped castings,ect],and then your trying to say that some assembly line workers making little more than minimum wage could? I personally love 3-2's both from a "looks" and a performance aspect,but IT AIN'T GONNA BE CHEAP to do a set up today.
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'37-4D
Well Known Member
Holley 94's are even harder to find and get parts for,but both Edelbrock and Speedway Motors have new,more modern replacement carbs[about 900 dollars for a set of three] available.Add linkake,jets,and a 3-2 manifold,plus breathers,and fuel pressure regulators, and you're still .looking at 1400.dollars to complete your set up.One of our more "senior" members[wrench?] may have a complete W set up,already done using modified 2 gc's that I think he said would run about 1500 dollars,which would be the best,easiest,smartest way to go for your application.The 94's were made for flatheads where 300 inches was a big engine.This where you'll trade "looks" for performance,kinda like those Thumper type cams trade "sound" over efficiency.A poor trade off,especially when you consider cost.An Edelbrock PerformerRPM small port intake new will cost you just under 400 dollars[new],and a Street Demon 625 will set you back less than 320[new],the Eddie 600 is just a little more than the Demon until you add the extra 20-30 dollars for the must have pholic heat spacer that you'll need for the Eddie carbs.You just have to decide.
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