73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Performance => Topic started by: 81C10 on February 16, 2008, 09:17:49 pm
-
I have a '73 C15 with a 307 with factory 2 bbl (Rochester 2GV)& factory intake. As far as I know everything is original. It has enough power (but more is always better 8)) I have an edelbrock torker intake and 600 CFM 4 bbl (only about 2 years old, came with a good running parts truck) that I'd like to put on it.
-Would I get much of a power increase?
-How much would my gas mileage suffer? Right now I get 14-16 MPG.
I have a 3 spd. manual and 3.08's. The truck that has the edelbrock carb is a 4x4 and TH350 w/ 3.08's and got 12 MPG.
What are your thoughts? Is it worth it?
-
You would be suckin with that intake on there. A good dual plane intake would help with a 4 bbl carb but putting that single plane manifold would work good with that 327 crank we were just talking about. ...maybe we need to build an online spare parts car lol
-
The Torker being a single plane intake is not what you want on a daily driver truck, especially with a 307. A Performer, or similar design dual plane would be far better. If you have a good working 14-16 MPG vehicle I personally would not change a thing. I realize everone wants to "tinker" with their truck, after all that is what it's all about, but I think this is one best left alone. Just my opinion, Lorne
-
I put a 4 barrel on my 68 elcamino inplace of the two barrel, and never could get it right. It ran like a dog, loved gas, and didn't matter what carb I put on it, nothing changed/. Put the two barrel back on, and ran great. On old race engine builder here said the 307 heads didn't really flow well enough with the low displacement to justify a 4 barrel. He stated," Just because you can put a 4 barrel on,doesn't means the engine can use it efficiently enough" Then pointed to his roundy round car with a 2 barrel holley. (I know the Holley two is bigger than the Rochester two). I may have had something wrong, or maybe there was a difference between 68 307 and a 73 307, I dont know, I kinda doubt it. These engines were 200 hp in 68 and the 350 in 81 was 165 hp,my 83 gmc 454 was only 215 pathetic horses, so if you have 200 hp with a 2 barrel getting 14=16 mpg, I wouldn't change,unless I changed the whole engine.Headers and exhaust are good mileage improvers. Maybe Vile or Captkaos can shed some light on the subject. It was a long time ago, but maybe I can learn so I don't repeat it in the future.
-
I didn't think 4 bbl would help that much. I'm definitly getting dual exhaust and *maybe* headers.
-
Trade that intake/carb for a small port dual plane(or just a performer) and put a good Q-Jet on it, There are ways to lean the Q-jet out to taylor it to the 307. I'll bet you'll get 2 or more mpg better.