What do yall have to say about the TPI airfoil? Does it actually help out? Is it a waste of money? Can you feel any differences with it installed? I'm curious because supposably it'll add about 7 hp. and help the air flow. Should i go ahead and buy this part or is it a waste?

 

I think it works fine.. instant horsepower? I cant say I noticed much. But for 20 bucks and 20 seconds to install.. WHY NOT!! get it man.

 

you wont notice a difference, but I think its a good supporting mod, like in addition to cold air intake and minor porting. I wouldn't spend $50 on one... $20-$30 sure... Its not a restriction like that tornado thing...

 

Thanks, do they all work the same or is there a difference in brands? what brand do yall have? and what did yall pay for them?

 

If you're not even mildly modified than even $20 for the airfoil is a waste of money. I had one on a heavily modified GTA. Didn't notice a difference with or without it. Put the cash towards something that will make a difference.

 

grind out the EGR walls behind the Tb instead of the airfoil. when i did that i did feel a doifference

 

Agree on the not worth 60, but 20-30 is good.

I picked the hypertech one, to me it looked more like a divider then the blunt nose of some of the others.

As for "does it work". I had a fairly accurate tune on mine, then installed the air foil. There were a very few spots I had to remove fuel(hurt), but quite a few up high I had to add some(helped). In your normal day to day driving, its not gonna help. But if you spin your motor in its upper rpms for any decent amount, it will help.

 

Its a "feel good" add on. You'll Feel good because you just spent hard earned money your gonna say you feel a differance to convince yourself you didnt just waste your money.....................................

 

It makes my throttle body look pretty when I have the intake off. But mine cost $60, But I got a free tpi intake with all sensors, TB, injectors and fuel rails with it.

 

Airfoils work but they are not all the same and generally not worth the money paid for them unless you get it for next to nothing.

Not everyone gets the same gain from an airfoil as it depends on the type of airfoil, the state of tune of the engine, and the entire combination of parts.

The tune of the engine can make the greatest difference on seeing a gain from an airfoil or many other types of bolt-ons that can add power. An engine that is running overly rich or is already seeing spark-retard may not respond at all to a modification. An airfoil is a small change, but under certain conditions can make noticable improvements in power. Just as throttle response can be improved by adjusting Acceleration Enrichment (AE) in the calibration, it can also be improved by an airfoil. Adding an airfoil is like reducing the amount of AE by a small amount. You may have so much AE that such a small amount won't make any noticable difference. Many cars have far too much, but not all.

Generally the more efficient the engine is already, the more gain you will notice by adding an airfoil. Again, generally SD cars notice more gains from an airfoil, but some MAF cars do too.

A car with a 305 TPI w/MAF and automatic w/2.73 gears may seem unlikely to gain anything from adding an airfoil, but sometimes they will depending on the state of tune.

Here are links to different types of bolt-on airfoils that range in price from $20 to $60.

http://i165.photobucket.com/albums/u...s/airfoil1.jpg
http://i165.photobucket.com/albums/u...airfoilSLP.jpg
http://i165.photobucket.com/albums/u...s/airfoil3.jpg
http://i165.photobucket.com/albums/u...airfoilJET.jpg
http://i165.photobucket.com/albums/u...s/airfoil4.jpg

IMO the Holley (last one) has the best shape for making gains on a flowbench, but it's also the most expensive at about $60 and definately not worth that.

I suggest making your own out of hardening epoxy for about $6.
Others on this site have done it and it is very cost effective. Here is a photo of one that I made so you can see the proper shape for air flow gains.

http://i165.photobucket.com/albums/u...rfoilepoxy.jpg



It seems like there should be a sticky or section for this in the tech articles. I haven't looked in a while so maybe there is one. It seems like a common situation.

 

I have read articles that indicated when air was pulled through the existing plenum and throttle body there was a loud noise due to air turbulence. The use of an air foil significantly reduced the noise due to less turbulence. However, this was at a larger amount of air being pulled through the system than what would occur with even a modified 350 TPI engine. Furthermore, the restrictions of the air cleaner, MAF sensor (if so equipped) and the rest of the air system reduces the flow of air for the airfoil to “smooth” out. The conclusion of the article was that airfoils produced marginal effects on airflow smoothing for normal or slightly modified engines.

I would say in combination with other airflow enhancements the effectiveness of airfoils may increase. On their website Holley suggests their airfoil will produce 5hp gains. I suppose they did some airflow and hp tests to make that statement; however, I would like to read the details of such a test.

I have not seen a comparison between the different manufactures of air foils with respect to HP gains. In the end you probably will not feel 5 or 7 hp much. Maybe that HP gain would be measured at times at the track or maybe not.

It is the sort of think that if you are doing other air induction and engine air intake improvements it may be worthwhile. There may be synergies realized such that when done in combination with other improvements the result will be more than the sum of the individual hp gains. However, I have seen no articles to verify that.

By the way I have installed a Holley airfoil. It was installed went I completely overhauled the fuel air induction system. Once properly set up I noticed a large increase in performance but I could not isolate how much of that was due to the air foil.