2.5L with lower revs/more torque, or 2.0L with higher revs?

[ZDan]

Originally Posted by jamesm

i know (and even said) that they make great power, that's not the problem. the problem is that, on the street, they feel sluggish. lots of power until about 4k then it just tails off to nothing at redline.

Please have a look at stock power/torque curves for the LS3, LS7, and LS9:
http://i1046.photobucket.com/albums/...Torqcurves.jpg
And then tell us again about "lots of power until about 4k then it just tails off to nothing at redline"!

makes it feel lazy. i drove a c5 corvette for a while, it was good fun, but nowhere near the experience of hitting boost in a 400+whp 2.0l 4-banger.

The C5's LS1 is a bit lower-strung, still not as "lazy" as you describe. Peak torque is above 4000 and peak power ~5500 IIRC.

Feeling a turbo "hitting boost" is more dramatic because of the big change in torque going from off-boost to on-boost. It feels fast, but it's really an undesirable characteristic (lag).

it's just a whole different experience. i prefer the 'pulls to the moon' feel over the 'could pull a house off it's foundation' feel.

I'll have to take you for a ride in the FD some day...

there is one exception: the new mustang coyote engine. test drove one, it has the torque AND pulls to redline like a banshee. if i had all the money in the world, i'd pull the turbo and put one of those in the fr-s

Good luck fitting that huge engine under the hood! Physically MUCH bigger than an LS.

Here's what the 5.0 looks like vs. LS3

The LS3 lords over the 5.0 up to ~6000rpm, DOHC 5.0 breathes better from there to its 7000rpm redline. Both make at least 350rwhp over a 1700rpm stretch. I like both, neither is "superior" in terms of output if you ask me. But the LS certainly is going to be a much easier swap into most platforms!

[Admiral Ballsy]

Originally Posted by ZDan

The C5's LS1 is a bit lower-strung

I'd actually say it's the opposite. The LS1 didn't really have a lot of low-end, not as much as the previous LT1 and not nearly what the L98 had. It 'woke up' around 4K, and as you say, power peak was only about 300RPM shy of redline (5800). The '01 cars got a new intake manifold that filled out the bottom end a little, but didn't change the peaks.

It might seem 'lower-strung' simply because the mechanical limit is so much lower, but the Gen IV engines have much more bottom-end. They just have a lot more top-end too!

Originally Posted by ZDan

I like both, neither is "superior" in terms of output if you ask me.

I do too. The Coyote is the first Ford engine in a loooong time that's equal to or more than the sum of its parts. IMO the LS engines have a lot more room for growth, both from power and displacement perspectives, though. About all you can do with the Coyote is go FI; there's not really any room for more displacement.

Put another way, an all-motor 500HP Coyote is a lot more expensive and 'finicky' than the same thing built on an LS3. And then there's the cost of the basic engine itself...

[ZDan]

Originally Posted by Sonolin

Is that dyno with a procharger kit or something?

Originally Posted by Admiral Ballsy

He doesn't specify what the engine is (at least that I see); the peak speed - about 6600 - matches an LS3/LS9. LS7s go to 7100, and that's about 60HP stronger than a stock LS7.

It's a 6.0 LS2 with basically LS3 top end (LS3 intake, L92 heads shaved for 11:1 CR), with a 222/230 .597" cam. That is a pretty optimistic rw dyno reading, it later dynoed similar curves but scaled down to 465rwhp/425rwtq, which seems a lot more reasonable.

[ZDan]

Originally Posted by Admiral Ballsy

I'd actually say it's the opposite. The LS1 didn't really have a lot of low-end, not as much as the previous LT1 and not nearly what the L98 had. It 'woke up' around 4K, and as you say, power peak was only about 300RPM shy of redline (5800). The '01 cars got a new intake manifold that filled out the bottom end a little, but didn't change the peaks.

Here's a stock '02 LS1 dyno:

Peak ~5300, limiter at 6200.
So yeah, it's not anything like falling flat above 4k as had been implied! God knows it was a revelation compared to the previous LT1 (I had a '95 Z28 M6) and the 250hp-from-5.7-liters L98 laughingstock!

It might seem 'lower-strung' simply because the mechanical limit is so much lower, but the Gen IV engines have much more bottom-end. They just have a lot more top-end too!

That am true.

[IceFyre13th]

Two choices, neither of which I would choose.....

My choice would be same engine, lower compression, with high boost (14 psi or more) forced induction (turbo would be first choice, supercharger second)

[StormTrooper]

Originally Posted by Superhatch

Assuming that Subaru/Toyota was listening to you, which would you choose? I think that these are both likely options as a high revving 2.5 is likely not in the works.

Choose wisely.

Weight reduction.......headers and more agressive tune.

if they did a CF roof and more aluminum parts got the car down to 2600 or close that would be perfect.

[OrbitalEllipses]

Originally Posted by StormTrooper

Weight reduction.......headers and more agressive tune.

if they did a CF roof and more aluminum parts got the car down to 2600 or close that would be perfect.

I would pay $35K for this car at 2600lbs with a 250hp 2.5L N/A that spins to 8K. That's gonna be a helluva lot more fun than an STI for $35K.

[mswhong]

Originally Posted by diss7

There's a 2 door, lightweight, rear wheel drive, good looking wrx? Kthxbi

Originally Posted by lickitysplit

Nope, but if all you want is moar power then having a 2door, light weight , rwd car doesnt matter.

In fact there actually is a 2door, light weight (albeit no rear-wheel drive) good looking wrx and that is the 22B!!

They are EXCEPTIONALLY rare. I think there are only 3 currently in australia and about 15 in the states?

What I would do for this piece of automotive history.. my god.

[OrbitalEllipses]

Originally Posted by mswhong

In fact there actually is a 2door, light weight (albeit no rear-wheel drive) good looking wrx and that is the 22B!!

They are EXCEPTIONALLY rare. I think there are only 3 currently in australia and about 15 in the states?

What I would do for this piece of automotive history.. my god.

[IMG ]http://all-carz.com/data_images/subaru-impreza-wr-x-sti-22b-coupe/subaru-impreza-wr-x-sti-22b-coupe-06.jpg[/IMG]

/swoon

There'll never be another 22B. Subaru's not in the position they were then; 3 WRC championships in a row, etc etc.

[mswhong]

Originally Posted by OrbitalEllipses

/swoon

There'll never be another 22B. Subaru's not in the position they were then; 3 WRC championships in a row, etc etc.

Of course.. but that's what our imagination is for right?

[Calum]

Originally Posted by OrbitalEllipses

/swoon

There'll never be another 22B. Subaru's not in the position they were then; 3 WRC championships in a row, etc etc.

Yeah, now they actually want to sell cars, not win races. The old days of win on Sunday, sell on Monday are gone it would seem. Now they're just trying to move product and that means not spending on things like the 22B. It is a shame.

[Mikem53]

Originally Posted by ZDan

Here's a stock '02 LS1 dyno:

Peak ~5300, limiter at 6200.
So yeah, it's not anything like falling flat above 4k as had been implied! God knows it was a revelation compared to the previous LT1 (I had a '95 Z28 M6) and the 250hp-from-5.7-liters L98 laughingstock!

That am true.

I had a 94 Z28 with the LT1 as well.. With a borla and an intake, it ran 13.6 @ 106mph.. It had an amazing low end off idle pull.. I then got a 98 Z28 LS1..
Definitely breathed better up top and pulled hard.. But lacked it out of the hole compared to the LT1.. The LT1 used that optispark thing that kept failing..
I skipped the LS2 and waited for the LS3 when I got my 08 corvette.. That's a great motor!

[OrbitalEllipses]

Originally Posted by Mikem53

I skipped the LS2 and waited for the LS3 when I got my 08 corvette.. That's a great motor!

I dream of all aluminum V8 swaps into this chassis. Possibly with built internals or a stroker kit.

[mrk1]

When I'm on the track high revving is always the way to go, but on my day to day 20min commute the 2.5 sounds better.