Need help with 5.0 build decisions

[boominXplorer]

Just picked up a spare motor and trans out of a 00 with 57k on it. The plan is to leave the block stock with the exception of a cam swap. The heads are going to be mildly ported with 1.6 rr's. The lower intake is going to be port matched to the heads and the upper is going to be ported for a 75mm TB.

JT will be powdercoating the upper, lower, timing cover and accesory brackets.

Current mods as of now are listed in my sig. I already plan to swap to a lightning mass air and use some type of computer tune. Need help on cam decision though. Comp Cams has 2 that I have been looking at.

35-349-8


Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.512 0.512
Duration At 0.006 Tappet Lift 264 270
Valve Timing At 0.006
Open Close
Intake 22 62
Exhaust 73 17
These Specs Are For The Cam Installed At 110 Intake CL
Intake Exhaust
Duration At 0.05 212 218
Lobe Lift 0.32 0.32
Lobe Separation 114





35-351-8



Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.512 0.512
Duration At 0.006 Tappet Lift 270 276
Valve Timing At 0.006
Open Close
Intake 25 65
Exhaust 76 20
These Specs Are For The Cam Installed At 110 Intake CL
Intake Exhaust
Duration At 0.05 218 224
Lobe Lift 0.32 0.32
Lobe Separation 114

 

[boominXplorer]

Also will stock valve springs hold .512 lift?

 

[reserved50]

75MM is too big, if the cam is too large (duration) you will lose braking power. Stock springs at that lift is really pushing it if it does go past 5K rpm, I've seen float (especially if you modify shift points/redline) with a milder cams on stock springs with higher mileage (springs can break also). Have you noticed if your FMS headers have a "tinny" kind of sound if you listen carefully?

 

[boominXplorer]

My other option would be to leave the upper unported and run a 70mm. I will be taking the motor to 5500 so valve springs will be upgraded.

The fms headers make all types of noises. Not to mention my drivers side blows an exhaust gasket every 6 months. I am going to get it milled and make sure its flat when I take my heads to the machine shop. I would like to get the torque monsters but I cant justify $600 for 10hp.

Vacuum for the brakes is an issue that I didn't think about. There are ways around it though.

 

[reserved50]

I have the FMS headers and they dont leak but everyone thinks they do from the weird noises they make, after a few adjustements and stainless lock washers on the bolts and pre-soaking the gaskets before install they "just" worked. I lost some vacuum with a dinky E-cam (282 in/ex and 220 at .050"), increasing the idle worked somewhat but if that doesnt work there are vacuum pumps that hook up to the booster. You should be ok as far as I : can tell. I wouldnt run the E on Explorer but I think my goal was to make driveability as ****ty as possible *makes Tim Allen grunting noises*

 

[boominXplorer]

bump for some opinions.

 

[Turdle]

You might tell us your honest goals with the truck-

 

[boominXplorer]

I want to keep most of the low end I have now and gain power in the RPMs. With 4:88s and the 5.0 its nasty down low but starts to fall on her face above 4K. This truck could also see boost in the future. I drive it just about every day but do have another car.

I run a truck accessory business and plan on making this truck the center of attention. While the drivetrain is out the whole underside is going to get cleaned up and repainted. Once the truck is back running after the swap it is going to be repainted.

My goal for the truck is to see 300/300 at the wheels. Might seem unrealistic to some but read up on GT40P porting and see some of the numbers people are running with a stock block.

 

[justin146]

My goal for the truck is to see 300/300 at the wheels. Might seem unrealistic to some but read up on GT40P porting and see some of the numbers people are running with a stock block.

How about some Pro Comp heads? I see those sell assembled for less than $700.

 

[boominXplorer]

Well I already have ped mount roller rockers and I am trying to keep it stock longblock for bragging rights.

 

[chriswells78]

Sounds strikingly familiar. I ported my upper out to 75mm to acomidate my 75mm Edelbrock TB so it can be done. Don't forget bigger injectors. If your figuing on 300, you probably want between 24 and 30# injectors. I've got a book around here that has a formula in it for injector size calculation.

 

[boominXplorer]

I already have some 24s from a cobra.