hypothetical 4.6l s/c vs. 4.8l s/c

**2-bowties&abird** · 04-22-2008, 04:40 AM

i hear time and time again about how either gm "cheated" by using a 5.7l or ford "cheated" by using a s/c. so in theory how would you guys think a s/c 4.8l t/a or ss would fair against the 4.6l s/c being that they are closer in c.i.d.

**hutch1999** · 04-22-2008, 07:24 AM

You forget DOHC vs pushrod, so you still cant really compare

**2-bowties&abird** · 04-22-2008, 11:24 AM

you think it would be that much of a difference? those 4.8's are turning around 280hp.

**Wesman** · 04-22-2008, 12:54 PM

I'm assuming you're comparing a GM 4.8 to a 4.6 DOHC, not a SOHC?? That makes a huge difference with the Modulars.

With identical mods and supercharger systems, I think they would make pretty close numbers.

**Chris Arnold** · 04-22-2008, 01:28 PM

You guys are smoking crack. The GM 4.8 would not hold a candle to the supercharged 4.6. That engine comes with a forged rotating assembly, and heads that flow almost 300 cfm stock. In n/a form it revved to 7k rpm with ease. If modified, there's no reason it can't rev way better than that. The engine made 320 hp in n/a form before any modification.

The 5.7 in the LS1s were a great race with the 4.6 DOHC in the Mach 1s. I don't think you'd find that the 4.8 would be a fair comparison.

**2-bowties&abird** · 04-23-2008, 03:41 AM

the 4.6 your reffering to is identical to the cobra 4.6 but an all aluminum version, 305hp 320tq. now given that you picked the most powerful naturally aspirated 4.6, what kind of hp do you think gm could have made with a 4.8l if it had been built for performance when they are turning 295hp 305tq in a truck platform.

**TrickStang37** · 04-23-2008, 06:45 AM

Originally Posted by 2-bowties&abird

the 4.6 your reffering to is identical to the cobra 4.6 but an all aluminum version, 305hp 320tq. now given that you picked the most powerful naturally aspirated 4.6, what kind of hp do you think gm could have made with a 4.8l if it had been built for performance when they are turning 295hp 305tq in a truck platform.

from what I've seen, all the 305 hp MaCh1's have made atleast the same rwhp, most of them a little more, than the 320hp 4.6L (not to mention rwtq as well).

I dont know if a 4.8L would make much more than the 295 hp (for a factory engine, at this point in time). Maybe 10 hp more im guessin.

**Chris Arnold** · 04-23-2008, 08:22 AM

Right on. The 4.6 in the Mach1 wasn't a downgrade from the Cobra. You can do some pretty wild stuff to an engine that's DOHC and rev to the moon much cheaper and more streetably than you can to a pushrod engine. I chose a pushrod engine for my go-fast platform, but I didn't realize until I got into high-dollar valvetrains the huge advantages of the OHC.

You're talking about production numbers, and in that case I have to agree with you. Making 300hp from a 4.8 is comparable to making 320 from a 4.6. If that's as far as you'd like to take the comparison then I'll concede it to you. However, that 4.6 is capable of so much more than it makes in stock form. You know there are V6s making 300 hp from the factory? Anyway, it's my belief that in terms of a performance platform the DOHC of the 4.6 outweighs the .2L from the 4.8.

Chris

**2-bowties&abird** · 04-23-2008, 09:38 AM

so you guys are saying the potential stops at 295hp for a 4.8? there has to be someone out there that has a built 4.8, i know it's not a good starting platform but it would be more comparable if we are talking c.i.d. i just don't believe that 295hp from the factory is the end of the line.

**andrew rs** · 04-23-2008, 10:52 AM

Originally Posted by 2-bowties&abird

so you guys are saying the potential stops at 295hp for a 4.8? there has to be someone out there that has a built 4.8, i know it's not a good starting platform but it would be more comparable if we are talking c.i.d. i just don't believe that 295hp from the factory is the end of the line.

im sure its not, but what they are saying is dohc is a better platform for speed. The 4.8 is a pushrod engine, making it not as happy to rev, and make power up top. shit throw head and a cam on a 4.8 and see what happens. im sure it wouldnt be much different than an ls engine. But no one really wants to build a 4.8 because there is better out there....

**2-bowties&abird** · 04-23-2008, 11:19 AM

Originally Posted by andrew rs

im sure its not, but what they are saying is dohc is a better platform for speed. The 4.8 is a pushrod engine, making it not as happy to rev, and make power up top. shit throw head and a cam on a 4.8 and see what happens. im sure it wouldnt be much different than an ls engine. But no one really wants to build a 4.8 because there is better out there....

sure i agree with that but i just wanted to throw out there that there are gm motors other than an ls1 that will make close to the same or more hp than their precious 4.6 dohc.

**TrickStang37** · 04-23-2008, 11:33 AM

Originally Posted by 2-bowties&abird

sure i agree with that but i just wanted to throw out there that there are gm motors other than an ls1 that will make close to the same or more hp than their precious 4.6 dohc.

Why didnt you just compare the northstar then?

Basically, in the end, all that really matters is whose heads flow the most when it all comes down to power potential.

**andrew rs** · 04-23-2008, 11:34 AM

Originally Posted by 2-bowties&abird

sure i agree with that but i just wanted to throw out there that there are gm motors other than an ls1 that will make close to the same or more hp than their precious 4.6 dohc.

gotcha, gm ftw all day. I need a t/a!!!! mid summer cant come soon enough.

**LGT Guru** · 04-24-2008, 07:42 AM

so how much hp can a built N/A DOHC 4.6 make?

**mogs01gt** · 04-24-2008, 09:06 AM

Originally Posted by 2-bowties&abird

i hear time and time again about how either gm "cheated" by using a 5.7l or ford "cheated" by using a s/c. so in theory how would you guys think a s/c 4.8l t/a or ss would fair against the 4.6l s/c being that they are closer in c.i.d.

I think those theories are fucking retarded. The mustang is lighter so it wins!!!!

**LGT Guru** · 04-24-2008, 09:15 AM

Lol mustang is lighter by what 100lbs, but its uglier so the f-bodys win

**xzaero0** · 04-24-2008, 10:17 AM

Originally Posted by 2-bowties&abird

i hear time and time again about how either gm "cheated" by using a 5.7l or ford "cheated" by using a s/c. so in theory how would you guys think a s/c 4.8l t/a or ss would fair against the 4.6l s/c being that they are closer in c.i.d.

How can putting a 5.7l in an Fbody be cheating? They only came with a 350ci motor or how long? Ford is the one who lost out when they went to a 4.6, they should have ran with a DOHC 5.0, that would have been bad ass later on...

IMO if it comes from the factory with something then it was ment to be and not cheating. I think all they did with the Termi was to raise the bar for general performance and after GM killed the Fbody they didnt see the need to continue.

**LGT Guru** · 04-24-2008, 10:35 AM

Why not, they need to beat the vette

**N20LT4** · 04-24-2008, 10:40 AM

Originally Posted by LGT Guru

so how much hp can a built N/A DOHC 4.6 make?

Not much. The 4.6 4-valves sucks from a naturally aspirated point of view. Even the honest Ford guys will tell you that. Just go look at Sean Hyland Motorsports catalog and look at how ridiculously priced the parts are, versus what you gain from them.