So I'm building a 347 that will have Trickflow 190cc 11R heads. I am going to use the stock 5.0 truck intake as it is already a decent flowing piece and have the lower ported. The guy who is doing my port job said that with a little welding and porting he can make the lower flow with the heads ~288cfm @.50 and 304 @.60 I asked about the truck upper and he told that the upper shouldn't be a restriction until I am over ~4500-5000rpms and that is only due to the long runners. Any thoughts or opinions on using the stock truck upper? I don't care about sacrificing some topend for more torque.


Anyone know of the flow on the truck upper? I've searched and searched and only found info about the lower.

 

what cam are you running/going to run? I cant tell you flow numbers on the upper, but that wont necessarily help you at all if I did.


a little more information on the setup would allow for better answers, mainly cam choice and rpm range, but also what you are going to do with the truck, or car if you came here to get information on a car you are putting together.


if torque is what youre after, leave it all alone except for port matching and blending the lower to the head ports, and remove any casting flash (or a polish) from the rest of the intake. I doubt you'll find the limits of the 5.0 truck intake if youre indeed building a truck engine spinning 6k or less. so maintaining the port size will keep velocity up.


using your head flow numbers @ .5-.6 as the goal isn't the best either, as your cam will likely be somewhere in the low-mid .5's. for max lift


more info plz!

 

The engine is going in a 88 f150 4x4 regular cab long box. I plan on using the truck for mild to moderate offroading, hauling small loads (heaviest would be a snowmobile trailer with 2 sleds) and as a DD during the winter. So I'm looking for torque from idle up.


I don't know the cam specs yet as it is being custom ground by Fordstrokers for me. I'm assuming it will be somewhere in the mid .5's for lift and short duration to maximize torque. The top end HP doesn't matter much to me, the motor is being designed to peak between 5500-6000 rpms and will probably not spend much time in that range.

 

then you want to leave the ports on the 5.0 manifold alone. just port match and blend the lower, but don't go hoggin it out. remove casting flash as possible - its not easy to get into the runners and may not be beneficial vs the effort. you could blast through the runners with very fine sand or bead, to try to polish the walls, but that effort is probably moot.


guys used to run the truck mani's on high revving 5.0s way back when the aftermarket options were limited. . .it flows very well and really isn't a good option for a torquey 5.0 (if that can be said in the same sentence). the fact that you are running 45 extra cubes should make use of the port and runner volume much better than a 5.0, but it will in no way be a hindrance. the 5.8 manifold is awful and mine still pulls hard to ~5500. even with heavy porting, its nowhere near even a stock 5.0 manifold, but my port velocity must be very high, and torque production confirms.

 

Thanks for the advice, its what I was hoping to hear. I'm having the lower done by Tmoss porting and they are experts at SBF intakes so I trust their work.