How much HP would you expect to gain over stock runners?

 

Check out this article.
http://xtremecarzone.com.au/index.php?showtopic=386

 

or maybe get some as&m runners .. they are very good runners

 

How much to expect over stock runners? On a stock engine with no other modifications, very little on a 350 and even less on a 305. Not worth the $400 if that's all your doing to the engine.

Add larger runners, ported ones are even better, with and aftermarket base (again ported even better) and ported plenum you'll see better gains. If done right the engine will breath better at higher rpm where stock tpi don't. Add a cam and tune and the runners have now become a better deal.

Now look at all the porting and money spent and the holley stealth ram does the same or better for less money. Not saying you shouldn't stick with a long runner manifold, just saying if you head down that road the hsr would be cheaper and worth a look.

 

In stock form to get much hp bang for the buck, port for a cam upgrade or larger cid 383 ect..

 

I dont think any tpi upgrades except for a first tpi is worth the money. 450 for edelbrock runners?!?! Screw that you can get a single plane with elbow and ls1 tb for 450

 

There's no way I'd buy the edelbrock stuff new. If someone wants to stay with original style tpi or needs to stay egr etc compliant then the classified boards are the place to look. Ported aftermarket stuff has been popping up all the time lately. Even then a hsr comes up cheaper and more effective.

 

I have only seen a few good sets of tpi parts pop up but still bring money.
Hsr and single planes seem more cost effective. But i wanted to stay emissions compliant in case i sell car