2003 for lighting Heads and cams, Read Please....

[joseph02]

Hello,
hey guys i have question about the lightning engine, so i did L swap to my 2002 mustang. and i keep reading on the internet that the lightning got a weak pistons road and can't hold more than 450 to 470whp. to get 450whp from what i read is i need cold air intake, MAfs, exhaust, 6lbs pulley and a tune. so i was thinking if i bolt a TF heads and stage 3 cams to reach 500whp will that put more load on the pistons road ? or i will get more hp thro making the engine efficiency better and it will not harm the roads ?

 

[Darren5.0L]

The connecting rods are generally accepted to be the major weak link in the stock engines. The pistons and crankshaft seem to be decent enough with the rods failing first.

The way you make your horsepower isn't quite as important as the overall stress placed on the rods themselves. You could have a higher HP engine that may survive the dyno, but may fail on the street or under heavy use, that said there have been engines that have been scattered at lower HP levels too. There are just so many factors in this.

If you are running a manual transmission, then that would place the rods under even more strain as power delivery and shock loading is much higher than your average automatic.

That's why the guideline is basically 450-470 HP, anything more, consider a connecting rod failure pending, you just never know when.

 

[joseph02]

thank for he the info Darren5.0L .
the way i was thinking that the load that might be on the road is caused by the high boost. so what was i thinking is that i could put enough load on the roads through the supercharger. and cheat the engine by better efficiency by using heads and cams in that way i could reach more hp without harming the engine.
so lets say that i have N/A engine with a week roads like the lightning, so if i put heads and cams it would put more load on the road or just making the engine rotate faster and stronger that it would make more hp ?
at this way that means that the heads and cams are not useful for the lightning engine. because i could pay more $1500 for heads and cams to reach 450hp or buy a pulley that is worth probably $150 and get the same power.
am just confused with how does it work.

 

[Darren5.0L]

I do follow your reasoning and in theory it does have a great concept but the rods aren't breaking just because of boost alone.

If you have the opportunity, read a copy of Iron Fist, Lead Foot. It is a great story about the development of the supercharged 4.6L with gave us the terminator.

The same issue cropped up, the "forged" powdered metal rods would randomly fail during the durability testing.

Off the top of my head the powdered rods were $6 each to produce while the manley units were $120 each. The same fabrication process was used for the 5.4L rods and they suffer that same weakness.

Bear in mind that supercharged Lightnings came a full 4 years before the Cobra got its blower and upgraded parts.

While I am not an engineer, I believe the stock rods fail due to stress, piston speed, and cylinder pressure as a combination.

Making more power with less boost may give you a little longer life but at the end of the day these rods have a limit that isn't much beyond 500 hp.

I remember when putting a blower on a stock 4.6L 2V and making more than 400hp was considered playing with fire for all the same reasons.

 

[DSG2003Mach1]

heads and cams may be slightly less strain on the motor then trying to spin the blower harder (which also raises air temps) but in the end youd still be toeing the line and now if something lets go it might take out your expensive new heads too.