ok, i have a 91 bolt-on 350 tpi. I am thinking of another easy upgrade and the only thing left to do would be a set of bigger runners or a throttle body, but i don't think a tb will really make a difference. What type of increases/decreases have you all seen with adding bigger runners to your cars? Any noticable loss of low end torque? I have 273 gears,so i am concerned about losing low end torque.

 

you wont lose much bottom end... but id spend the cash on a set of 3.42's or 3.73's .. then you really enjoy your car!

 

the loss on the bottom end is pretty insignificant you wont notice it.
If you post in the TPI section you'll get a bit more help.
You should see some gains with runners especially if you port the plenum as well.

 

Yeah, plenum is already ported and siamesed. Just wondering if the runners, preferrably the SLP runners were worth it. I do have th option of doing the rear swap. Guy wants $75 for a 342 rear end, drum to drum. Do you really think that going from a 273 to a 342 will be that big of a difference?

 

That 2:73 to 3:42 rear end swap will be the biggest bang for the buck you will ever get for $75.00 you will "feel" 10x more seat of the pants difference than you ever will from bigger runners.

 

The SLPs are worth it if you buy them used. I wouldn't pay $400 for them .
But they are the best due to the fact that they can be ported so thoroughly,
though out of the box they don't flow as good as other runners

 

i would jump all over that 3.42 deal... you will feel a BIG increase in off the line torque... slp runners imo are only worth it if you can port them..