Changed IAC motor and cleaned out holley. Pic's and video inside!
That does sound a little weird!
The Fastman (and you can to with proper equipment) also bores them out. Stock is a tapered 50mm (approx) to 47 or 48 mm (can't recall exactly). He bores them out so they're a straight 50mm all the way through (recommended for 5.2L V8), or a 52mm all the way through (recommended for 5.9L V8). Even bigger, if you want him to, if you have a heavily modified truck.
I have the 52mm, and I think it was worth it. It gives you more top end mostly, not a whole lot of improvement at the low end though. Its a little easier to increase speed when already cruising at highway speeds.
I mirror everyone else's thoughts though... fix that plenum gasket first. You can buy a kit for that (plenum plate, gasket, bolts) from Hughes or APS for under $100, and if you wish, do your own labor. Thats less than half the cost of a Fastman.
I have the 52mm, and I think it was worth it. It gives you more top end mostly, not a whole lot of improvement at the low end though. Its a little easier to increase speed when already cruising at highway speeds.
I mirror everyone else's thoughts though... fix that plenum gasket first. You can buy a kit for that (plenum plate, gasket, bolts) from Hughes or APS for under $100, and if you wish, do your own labor. Thats less than half the cost of a Fastman.
i bored my spare out to 50mm on a milling machine and it didn't work out for me with the stock throttle plates. the stock plates are also 50mm, but they sit in the throttle body at a slight angle. there is a gap on either side of the plates because of that angle on them and it made my truck idle at 1000 rpm because of the extra air coming in that the IAC couldn't make up for.
if i were to run the throttle stop screw in a little to make the plates sit perpendicular to the TB bore then the tab on the end of the bar that goes into the TPS would make it give false readings (or so i would think, haven't tried it).
before

working on it


after
if i were to run the throttle stop screw in a little to make the plates sit perpendicular to the TB bore then the tab on the end of the bar that goes into the TPS would make it give false readings (or so i would think, haven't tried it).
before

working on it


after
You could bore the the throttle body out to 2 inches, which is 50.8 millimeters. That way you can use these throttle plates from Summit:
http://www.summitracing.com/search/D...?Ns=Rank%7cAsc
Fastman uses a 1.98 inch bore, or 50.3 millimeters. Thats only a .5 millimeter difference. Not much of a difference at all. Although this is closer to the 2.03''/51.75mm bore he uses for the 360s, I wonder if it would really make that big of a difference in a 318? JMHO that is better than $235 to get almost the same thing.
http://www.summitracing.com/search/D...?Ns=Rank%7cAsc
Fastman uses a 1.98 inch bore, or 50.3 millimeters. Thats only a .5 millimeter difference. Not much of a difference at all. Although this is closer to the 2.03''/51.75mm bore he uses for the 360s, I wonder if it would really make that big of a difference in a 318? JMHO that is better than $235 to get almost the same thing.





