Hello,

This is probably going to be a long message but here we go...

I have a 1997 Expedition 4.6 with about 230,000. It has been a good truck but it's performance has gotten worse. Before something breaks, I want to rebuild the engine and then add a supercharger, new tranny and new exhaust. I want to get at least 320hp out of her.

My question is whether or not I should rebuild the old engine or try to find a 2002-3 engine with PI heads?

Or should I buy a longblock (with PI heads) from a shop? If so who do you guys recommend?

Thanks.

 

I'm not trying to discourage you from supercharging, but if 320 hp is all you are looking for, then you can get that rather easily in naturally aspirated form.

I have a '98 4.6 with Airforce one, Borla, pulleys, fans, MSD coil packs, Densos, wires, 24# injectors, 190 lph fuel pump, pro-m mass air meter, JBA headers, and Superchip with custom tuning. There is no doubt in my mind that I am making the power you are talking about.

My point is that if you are willing to put in the effort (cash), you can make far more than 320 hp.

Were I you, I would give Mike Troyer a call. He is not the only one who knows anything around here, but he would have opinions worth hearing. His number is all over the Computer chips forum.

Perhaps you should consider replacing your 4.6 with a 5.4. That stock motor will give a bigger base for later mods.

 

Don't know how much you plan on spending, but I have seen several complete Lightning engines w/trannies on ebay with a buy it now for $7500.

Not sure what all this swap intels, but I guess it would be worth looking into. A lot of talk has went around the boards about putting superchargers on the N/A 4.6 and 5.4 and it seems to be more work than its worth.

Just do a search for superchargers if you are interested in going that route. Keep in mind that the 01-03 L's produced 380 HP stock.

 

Do you want 320 hp at the flywheel (Crank) OR do you want 320 hp at the rear wheels (rwhp)? I am thinking you meant 320 rwhp? If so, this would mean about 400 hp at the flywheel. I think our stock crankshafts are rated for 400 hp.

For 270 - 330 rwhp and 350 - 400 rwtq. You could get a used but very low mileage (better than rebuilt) complete 4.6 long blocks with PI heads (started in 2001 for 4.6) from places like
car-parts.com, for 1,000 to 1,500! Then add a supercharger kit (new or used $2500 - $5000). Of course this does not include other drivetrain rebuilds or upgrades.


Note: For comparison, a stock 01 - 03 Lightning produces 380 hp at the flywheel and around 290-320 rwhp and 390 to 420 rwtq. Although, that is at the stock 8 psi of supercharger boost.

 

Thanks for everybody's help. I guess what I meant is 100hp more than what I had stock.

I like the idea of buying a 2002 from car-parts.com and adding a supercharger.

I am estimating that this will cost me between $8-10K including the tranny. Do you guys know somebody that builds good/strong trannys? I would be willing to send my tranny out or just buy one already built for extra horsepower.

Thanks.

 

factory tech in the L forum can help you with your tranny needs.