how do i get to 7000rpm red line

[stanggt00]

ok my question is simple most of the 4.6 stangs have a red line of about 6-6.5k
what i want to know is whats more important the heads or the bottom end when it comes to moving the red line of a motor up

example it in the heads is it the camms or valve springs
in the motor is it the type of rods or crank

or could it just be in the computer or a combo of all of these things



my goal here it to put together a nice motor that can hold about 500-600hp
with a red line of about 7000rpms

 

[sgarlic]

Everything you mentioned is involved, but the main thing keeping us from 7k is the crankshaft.

 

[reddrgn01gt]

Too hold that kind of power and spin that high you will need a forged bottom end and cams + valve springs.

 

[CanadaStang]

ok my question is simple most of the 4.6 stangs have a red line of about 6-6.5k
what i want to know is whats more important the heads or the bottom end when it comes to moving the red line of a motor up

example it in the heads is it the camms or valve springs
in the motor is it the type of rods or crank

or could it just be in the computer or a combo of all of these things



my goal here it to put together a nice motor that can hold about 500-600hp
with a red line of about 7000rpms

Generally the first bad thing to happen is PTVC.

 

[01Steeda]

Generally the first bad thing to happen is PTVC.

thats what happened to me lol.

cams/valsprings.. crank.. should do it. I wouldnt say I am at a 7000 redline, but my rev is set there now

 

[DropTopPony]

buy a cobra

 

[DBMSTNG]

a well balanced rotating assembly, heads, cams, and proper valvesprings will do it.

 

[03ghoststang]

what everyone mentioned above but a 4V would get you there faster also how much are you willing to spend for that is a big question....

 

['13_ImpactBlue_GT]

Whats PTVC? Piston to Valve Contact?

 

[helty]

Whats PTVC? Piston to Valve Contact?

yes

 

[TGJ]

Everything you mentioned is involved, but the main thing keeping us from 7k is the crankshaft.

No, it is the stock valve train in the heads that prevent a higher RPM limit. Valves float at the higher RPM causing PTV and blown motors. The next issue is the stock pistons and rods.

There is nothing wrong with the stock crankshaft. With proper pistons/rods and a good valve train in the heads, the only thing preventing an even higher RPM is the heads. I know of quite a few cars that are pushing over 7500 RPM on the stock crankshaft with no problems, however these cars do have forged pistons and rods as well as upgraded heads.

Show me an example( Post a link ) of a failed 2V crankshaft where the crankshaft was the problem. I have asked for this at other boards and have yet to see an example of it.

 

[QDRHRSE]

TGJ-

I agree. It's the connecting rods that fail. I've learned a lot about this stuff with my Lightning. The 4.6's actually are a lot stouter than everybody thinks. What kills them is detonation after 400rwhp. People get too aggressive with their tunes, run the too lean, detonate, and then lose a rod. If you keep them rich you can see 500hp with less problems....I didn't say no problems....less.

 

[stanggt00]

hmm thxs for the input guys

so a forged motor with some camms and heads should do it

question about the 4v is it a direct swap

i mean can i just drop a mark 1 motor in my gt and be happy with out a lot of modifications

 

[Stang|ess]

you don't need a forged block to rev to 7000.

cams, head, and don't forget valve springs. I'm assuming stage 2 cams would be in this application, so don't forget supporting mods such as gears.

 

[sgarlic]

.. or toilet paper.

 

[jstreet0204]

Everything you mentioned is involved, but the main thing keeping us from 7k is the crankshaft.

KenB on modular depot revs to 7500 with a stock cast crank.
n/a 4v motors have a 6800 redline with the same rods and pistons as the 2v's have as far as I know. So I don't think the bottom end is a problem if the valve springs are strong enough to keep the valves from floating and hitting a piston.