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EMCD
02-07-2011, 11:04 AM
What after market carb should i get for my cuda? my original carb is shot.

ramenth
02-07-2011, 11:39 AM
What after market carb should i get for my cuda? my original carb is shot.


What's your price range? Edelbrock's can be had starting at $275. Holley Street Avengers start around $329.

burdar
02-07-2011, 12:31 PM
Send your origonal carb to Scott Smith for a rebuild/replate.

http://www.harmsauto.com/iHarms_Carburetors.html

burntorange70
02-07-2011, 01:07 PM
What after market carb should i get for my cuda? my original carb is shot.

Should be a thermoquad you have now right? Going from a spredbore to a squarebore carb will require an adapter to make it work with your stock intake. You an get them from Jegs or Summit racing.

Or seeing as you want to get a little more power from your motor now is a good time to get an intake too. A Holly 750 vacuum secondary carb and a dule plane intake would be the way I would go.

EMCD
02-07-2011, 02:02 PM
cool. how much does a rebuild cost? ARe used carbs off c-list worth the risk? i found a carb and intake for $250.
http://denver.craigslist.org/pts/2200240317.html

burntorange70
02-07-2011, 02:22 PM
cool. how much does a rebuild cost? ARe used carbs off c-list worth the risk? i found a carb and intake for $250.
http://denver.craigslist.org/pts/2200240317.html

Says $375 on that link Burdar gave for a rebuild of a thermoquad.

That Ebrock carb should be just fine but the intake is not a very good match to your motor. The Performer intake has small runners and is more for a 318. I would recommend going with a Performer RPM instead.

EMCD
02-07-2011, 02:40 PM
cool. will the carb and intake change add a lot more power and better response?

burntorange70
02-07-2011, 05:18 PM
It is a good mod to do and will be even more so when/if you do a cam/exhaust upgrade. Would say stay away from the Eddy carb. off idle response is not all that good and they are known to have heat soak problems. I have one on my 70 340 I do not like and am going to switch it out for a Holly or Demon carb when I rebuild the motor.

EMCD
02-08-2011, 10:03 AM
thanks. what model should I buy? is it worth buying the intake as a package from Summit racing?

burntorange70
02-08-2011, 10:03 PM
What all are you planing to do to the motor? Any other upgrades planed down the road?

EMCD
02-08-2011, 10:13 PM
i'll look at getting headers and new heads, (not sure about ported iron verse the aluminum ones. It really all depends on what my compression #'s come back at. I'm getting the local garage to change all my fuilds and clean the gas tank. if the compression is good I'll add the heads, if it's bad I'll figure out some new bore and add HP from the interals.

EMCD
02-09-2011, 11:29 AM
So, if my compression comes back decent. what kind of HP can i expect from a RPM intake Holly 650 cfm carb and a performance cam?

burntorange70
02-09-2011, 05:52 PM
So, if my compression comes back decent. what kind of HP can i expect from a RPM intake Holly 650 cfm carb and a performance cam?

Unless it has been rebuilt a 72 340 should have about 8.5 CR. I would say some thing around 300-325 HP. Give or take with or with out headers. If it is more like 10to1 then 325-350 HP with or with out headers. Depending on cam used.


Just depends how far you go. Need to get a build plan together.


With 8.5 CR, mild cam, and RPM intake. I would run a 650CFM carb.


If you also go with headers and have more like 10-1 CR and some head work I would go with a 750 CFM carb. This should get you close to 400 HP



As far as what carb to get I would go with a vacuum secondery Holly.

EMCD
02-10-2011, 08:22 AM
Ao,
With th3 340 with the 8.5 CR, mild cam, and RPM intake and a 650CFM carb will bring me what rough amount of HP?

burntorange70
02-10-2011, 11:03 AM
Ao,
With th3 340 with the 8.5 CR, mild cam, and RPM intake and a 650CFM carb will bring me what rough amount of HP?

Maybe around 300 HP.

EMCD
02-10-2011, 11:50 AM
wow, so not that much of a gain. Would it be worth jsut putting in a 360? On C-list there is a 360 with all the trimming that dynoed at 450HP. The seller says it has less than 1k on the rebuild. He wants 1.2k obo. what do you think?

swright
02-10-2011, 12:04 PM
On my '73 340 I went with a 650 cfm Edelbrock AVS carb on the Edelbrock stock replacement intake. I am returning mine to original configuration (removed a medium rise Edelbrock with a 750 Holley) although the AVS was only correct for a '70. Both available through your local NAPA at better prices than the specialty suppliers.

burntorange70
02-10-2011, 01:20 PM
wow, so not that much of a gain. Would it be worth jsut putting in a 360? On C-list there is a 360 with all the trimming that dynoed at 450HP. The seller says it has less than 1k on the rebuild. He wants 1.2k obo. what do you think?

72 340's lost some hp. Think they were rated at 240HP where as the 70-71 were 275. So it is a bit of a gain.

Got a link or specs on it? Sounds like a good deal for only 1200.00 bucks. Could not build your motor to that point for that price.

EMCD
02-10-2011, 03:10 PM
yep, here's the c-list bio
i need to sell my hot rod engine. it was originaly in a 1975 chrysler cordoba. i had it built for my scamp but its gone now so i need to sell the motor. its bored 30 over, heads ported and polished, edelbrock performer 4 barrel intake, "pro stock" brand valve covers that are really cool lookin. if i get enough i will include the eddy 650cfm carb. all the machine work and assembly was done by gp machine shop in cheyenne, wy and they said it would be really close to 450 horse at the crank and it was really powerfull the little i had it in the car. it dosent have even 1000 miles since the rebuild. i would do partial trade for honda parts but need at least half cash.

burntorange70
02-10-2011, 03:36 PM
Hmmm. Not much info to go on there at all. Be nice to know the CR,what heads and what have been done to the, cam specs, piston, rod brand, crank stroke and if it is cast or forged.

Sorry don't know what to tell you on that. Could be a good deal or he could be full of it. LOL Takes a lot to get a motor to 450 my first thought after seeing that guys add is he is being a bit optimistic on the HP# but with out more info it is hard to know.

EMCD
02-10-2011, 03:43 PM
I have a call into him to ask where in WY the engine was built. If i can get him down on price, i could grab all the good parts and throw them on my 340 if the compression # on my block come back decent, right? My block has 100k miles, should I expect the engine needs a complete rebuild?

burntorange70
02-10-2011, 03:51 PM
Do you know for sure it has never been rebuilt? Only way to know is to go through it and see what it looks like.

EMCD
02-11-2011, 08:44 AM
I bought it from the orignal owner and he was 99% it had never been rebuilt. I also have some strange oil patch on the rear passanger side wheel well. It looks like something was or is spraying oil in the wheel well and it looks like it's in the trunk to. Could this be an axle seal?