273 Headers (weird combo)

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chrissock

chrissock

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I've been searching for a few hours now and I cant seem to find a great answer. Have a 71 Dart swinger, 273 with larger port heads on it. Power steering is stock and I'm trying to maintain column shift. Its a 727 trans and I will have to use an adapter to cable style. Its a conversion car so /6 k member. If I look at headers for the 318 or 340 they should work with the larger port heads correct? I see TTI is probably the best option but these are kinda temporary so wondering if any cheaper brands will work even if I have to fight with them. Any help appreciated.
 
chrissock said:
" If I look at headers for the 318 or 340 they should work with the larger port heads correct? I see TTI is probably the best option but these are kinda temporary so wondering if any cheaper brands will work.........
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TTI work fine for me, I would expect others to fit, but not ever as well from my experience, you have a tough decision to make bang vs buck in a short-term situation.
My experience is with a stock head 273 in a 62 Polara500 (Dart).
 
Factory 318 is same port size as a 273. 340/360 share the larger port size.
So depending on which heads you actually have, any 273/318 or 340/360 header for your year Dart should work (provided they will accommodate power steering).
I don't quite follow what you have for a transmission (cable shifted 727 for smallblock I think?), but be aware of convertor register differences on pre and post 1968 crank flanges and convertor snouts... I'm not aware of any aftermarket shifters anymore that accommodate the early cable-shift transmissions.
 
Professor Fate said:
Factory 318 is same port size as a 273. 340/360 share the larger port size.
So depending on which heads you actually have, any 273/318 or 340/360 header for your year Dart should work (provided they will accommodate power steering).
I don't quite follow what you have for a transmission (cable shifted 727 for smallblock I think?), but be aware of convertor register differences on pre and post 1968 crank flanges and convertor snouts... I'm not aware of any aftermarket shifters anymore that accommodate the early cable-shift transmissions.
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The Trans is a standard small block 727. I just mean that instead of having all of the linkage to use the column shift, I found a kit that allows you to use the column shifter without all of the linkage.
 
J-c-c said:
TTI work fine for me, I would expect others to fit, but not ever as well from my experience, you have a tough decision to make bang vs buck in a short-term situation.
My experience is with a stock head 273 in a 62 Polara500 (Dart).
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Yea I agree. Eventually I am trying to get to twin turbo but the dollars are not there right now.
 
chrissock said:
The Trans is a standard small block 727. I just mean that instead of having all of the linkage to use the column shift, I found a kit that allows you to use the column shifter without all of the linkage.
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Huh?
 
First off, it sounds like a cobbled up mess. The 71 Dart did not come with a 273 and most of the 273 cars had a 904 transmission. Whatever you have, you need to post pictures because we cannot see what "you" are looking at.
 
chrissock said:
I've been searching for a few hours now and I cant seem to find a great answer. Have a 71 Dart swinger, 273 with larger port heads on it. Power steering is stock and I'm trying to maintain column shift. Its a 727 trans and I will have to use an adapter to cable style. Its a conversion car so /6 k member. If I look at headers for the 318 or 340 they should work with the larger port heads correct? I see TTI is probably the best option but these are kinda temporary so wondering if any cheaper brands will work even if I have to fight with them. Any help appreciated.
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Other than the great fitting but a bit pricey TTI or Doug headers, the best fitting and amazingly cheapest header I found is the best one I have used with a thicker 3/8 flange (longer header bolts required of not in the box) are the headers by Summit Racing.

I have a set in use right now. But! There the typical 3 tubes under the steering linkage type that are actually the biggest PIA to install and remove.
 
If you have 340 or 360 heads (large exhaust port) just use 340 headers. Only difference between a 340 and 273 is piston diameter and that that will not make a difference in header selection. Only the exhaust ports. What head castings are on your engine?
 
chrissock said:
The Trans is a standard small block 727. I just mean that instead of having all of the linkage to use the column shift, I found a kit that allows you to use the column shifter without all of the linkage.
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Okay, this is where you will need to take the convertor register differences that I mentioned into account. Depending on the year of your 273, a '67 and earlier crank will not properly mate to a '68 (the year small block 727s were introduced in pass cars, with the introduction of the 340) and later 727 trans and convertor because of the register differences. If it's a '68-'69 block/crank you should be okay.
Please post a link to the column cable shifter kit you spoke of- I've never heard of such a creature before.
 
What's your fascination for not using the factory column shif linkage? That's actually the easiest way to do it and all of the Hedman style headers like the Summit and Flow Tech brands that are around and under $200 will fit and work fine with factory linkage. Use the factory linkage. You don't need to try and reinvent the wheel here.
 
I guess I was unaware that there are 273 headers, 318 headers, 340 headers and 360 headers. Maybe I've used 318 headers on my 340's??
:rolleyes: :eek:
 
318willrun said:
I guess I was unaware that there are 273 headers, 318 headers, 340 headers and 360 headers. Maybe I've used 318 headers on my 340's??
:rolleyes: :eek:
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Some headers, need to be modified to use the smaller ports on early heads. Forget whose, maybe TTI? Usually big is OK unless they leak.
 
66fs said:
Some headers, need to be modified to use the smaller ports on early heads. Forget whose, maybe TTI?
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I've not used TTI's. I know Doug's, Hedman's, Cyclones, and a few others I have used have "small block" headers. I've used on small port heads (273/318) and large port heads (340/360) and no issues.
 
66fs said:
Do you remember what year small port heads

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through the years, just about every year.... lol. I don't know exactly. 70's, 80's, 90's, LA's, Magnum's.... I guess recently, I just put Doug's on my '76 318 heads.... Just had hedman's on my '85 318 in a truck, same headers are now on the 5.9 magnum in the truck..... Just put Hedman's on a '77 318 in a van .....
 
318willrun said:
through the years, just about every year.... lol. I don't know exactly. 70's, 80's, 90's, LA's, Magnum's.... I guess recently, I just put Doug's on my '76 318 heads.... Just had hedman's on my '85 318 in a truck, same headers are now on the 5.9 magnum in the truck..... Just put Hedman's on a '77 318 in a van .....
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Looks like TTI is where I saw that, read down the notes list for early A-Bodys. Around the early 70's the heads had the large exhaust flange for the egr ports so plenty of flange to seal the ports. Early 340's had much larger exhaust ports than early 273 and 318.
 
66fs said:
Looks like TTI is where I saw that, read down the notes list for early A-Bodys. Around the early 70's the heads had the large exhaust flange for the egr ports so plenty of flange to seal the ports. Early 340's had much larger exhaust ports than early 273 and 318.
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Early A-bodies, now, are a different animal. But the OP has a '71, so not an issue. And yes, 340's/360's have the large ports for the small blocks. And, it really doesn't matter which years. A '89 360 exhaust port will be basically the same size as a '68 340. But the small block headers in general work great on either 273's or 340's.
 
and.... don't get caught up in "273 head". Same port as LA318.
 
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