Dyno Comprison LS1 vrs 5.0 Combos

[reddy351]

Yep, we are reading the same thread It is a good one...

Of course a 347 can hit over 400rwhp, but I have not seen many , if any at all hit 400 rwhp with AFR 165's and similar parts to match.

The ls1 is hitting well over 400 rwhp with stock heads (similar to AFR 165's), and a stock intake and full accessories

The 347's with over 400 rwhp, all have larger heads than the ls1, larger camshafts, and I am not to sure on the intake and a comparison between it. I will have to look into that sometime later.

I never questioned that the 347 could hit 400 rwhp Pokageek, but I see ls1's doing more with less, rather than the other way around. There are TONS of h/c ls1's with over 450 rwhp. I do not see to many 347's strapping down that kind of power on a chassis dyno with the same type compression/powerband/accessories as the ls1 combinations out there.

But hey, I love the 331 and 347 and they both can get you moving in a hurry

Grady - Nope, I think your comparison graphs are great because you provide so many varieties for us to put together. Keep it up...

Anyways, off to study

I couldn't tolerate driving anything that the LS? engines came in. (Poor build quality/engineering/ergonomics.) I'll take my wimpy little 302 and my SOLID Mustang, everytime!

 

[Pokageek]

The LS1 heads though have 200cc intake 170cc exhaust 2.00 intake valves, 1.55 exhaust valves, and flow around 230/179 @ 600" also a 10:1 CR

It would be neat to see a 347 with the same compression, heads that flow close to the same as the LS1's,and with similar cam profiles,and induction, to see who comes out on top.

Good posts. Just curious..Anyone have this close a comparison?

Again, I lean toward the CID to CID argument. Unless... the bowtie computers superior enough to land a great edge over ours? Grady, being the tweecer guru maybe you have some input there. If 5spd is right... why the difference...

 

[onlyme]

1 thing I'm not a fan of ,is the LS1 engine being you only see about half of it when you lift the hood of an F-body, and it looks even more cramped and harder to work on. At least in a mustang you can see the whole motor and it's easier to work on it seems.

 

[final5-0]

Good posts. Just curious..Anyone have this close a comparison?

Again, I lean toward the CID to CID argument. Unless... the bowtie computers superior enough to land a great edge over ours? Grady, being the tweecer guru maybe you have some input there. If 5spd is right... why the difference...

I honestly don't know all that much about Chevy stuff
hence
My having to ask if my understandings about the LS1 are valid

Having said that ... I certainly wouldn't know anything about their pcm's

It would make sense to me if you had the chance to have some of the best
engineers (which Chevy certainly does have) start from scratch and design a
push rod motor, you would have the benefit of technology learned since the
sbf 221 cubic inch motor was designed and built. Sure ... we call that motor
a 5.0 these days but nothing major has changed since way back then.

Its not like Ford hasn't been doing anything

Ford just did it with a tiny mod motor
and
Chevy did up the LS1 with pushrod technology

So ... when we try and compare pushrod to pushrod motors

All we got is a design from the early 60's to compete with

Just some of my thoughts here

Grady

 

[reddy351]

Good posts. Just curious..Anyone have this close a comparison?

Again, I lean toward the CID to CID argument. Unless... the bowtie computers superior enough to land a great edge over ours? Grady, being the tweecer guru maybe you have some input there. If 5spd is right... why the difference...

Well, it can't possibly make more or less power, based on the name that's on the valve covers. That'd be silly.

 

[zenboy99]

I remember reading on hardcore50.com (NOT 50hardcore.com) that the LS1 has the potential to make more power because of its cylinder head design. This was coming from the guys that put together heads and cams for a living.

Also, I think its hard to compare flow numbers between different styles of heads without knowing the port length and cross section area. Just like its hard to compare a 170cc Twisted Wedge head with a 170cc GT40X head, the Twisted Wedge head has a shorter intake port, larger cross section, but the same port volume. Given that alone it should flow more.

I'd be curious to see what Ed Curtis would have to say on this thread since he specializes in LS and Ford pushrod stuff. He brought up some interesting stuff on the other site.

 

[Pokageek]

haha 50 hardcore.com. I just looked there. The words and the pics... don't match lol.

 

[final5-0]

I remember reading on hardcore50.com (NOT 50hardcore.com) that the LS1 has the potential to make more power because of its cylinder head design. This was coming from the guys that put together heads and cams for a living.

Also, I think its hard to compare flow numbers between different styles of heads without knowing the port length and cross section area. Just like its hard to compare a 170cc Twisted Wedge head with a 170cc GT40X head, the Twisted Wedge head has a shorter intake port, larger cross section, but the same port volume. Given that alone it should flow more.

Well said Chad

That is pretty much the point I was wanting to get across

Some of the time ... things just are not on an even basis
thus
You could never work things out for a FAIR comparison

I guess I was just trying to look at both
and
See how close to fair it would be

never the less ...
its informative and fun to see what others have done

Grady

 

[final5-0]

This thing is approaching 500 views

Who would'a thunk it

Grady

 

[2002VertGT]

Chad, what did the LS1 you were running against on Sunday have done to it? The few passes I saw he was in the 12.60's

 

[5spd GT]

Good posts. Just curious..Anyone have this close a comparison?

Again, I lean toward the CID to CID argument. Unless... the bowtie computers superior enough to land a great edge over ours? Grady, being the tweecer guru maybe you have some input there. If 5spd is right... why the difference...

Try post #34 Pokageek...

http://forums.stangnet.com/showthread.php?t=724636&page=2

Ed Curtis, Jay Allen, all state how the ls1 is better. You know how they are about "myths"

GM has made pushrods forever, they just worked with it a little more, instead of keeping the same design.

zenboy99 - Your right, flow numbers for heads are only part of the equation. But currently, that is all much of us have to work with

I agree the heads are a key component. Each intake and exhaust port is matched almost to a "T" to eliminate any inconsistent runners.

The ls1 intake port does not really turn right or left, but has tall intake ports and the ports taper down a little before it runs over the intake valve to gain air speed. This set-up allows for very directional air into the combustion chamber The ls1 head designers also directed the injector target to hit in-line with the ports to the back of the intake valve. The 15* valve angle helps as well, compared to Ford's 20* valve angle, coupled with a lighter valvetrain.

The pistons actually partially stick up past the block from the factory

The lifters, pushrods and the valve stems are parallel on the same centerline which helps reduce friction as well...

Intake runner length is 15 inches by the way.

A lot of little things add up to a slight advantage over the 347 is how I see it.

 

[Pokageek]

No disagreement. I think you are missing my point... it's mostly in the heads and stuff above the block. No mystery no myths.

 

[5spd GT]

No disagreement. I think you are missing my point... it's mostly in the heads and stuff above the block. No mystery no myths.

Cool,

Yeah, I agree, "most" of the advancements that help are top-end partial.

The bottomend is another story.

 

[Pokageek]

The other thing is that if they are rated at say 305 HP from the factory...that is way off. For example, we know from dynoing our stock stangs that they rw dyno like 180ish... in general..thats 20% driveline loss.

The correct HP on an LS1 will be more like 380HP!! um wow! That is pretty amazing from the factory, lol!

 

[5spd GT]

The ls1 cars actually have around 330-335 hp, and some more, depending on options.

GM did this so the Vette at 345-360 hp (depending on years), looked even better. When in fact, they have the same basic engine.

The 5.0L with 180 rwhp is also typically an old worn-out engine. New, they ran in the 190-195 rwhp range.

 

[Pokageek]

Hehe, I like you 5spd but we may be butting heads there a tiny bit too . If I am sounding argumentative I don't mean to but I am giving you my opinions based on factual stuff I have read so its not just all opinion. if I get outta hand just smack me back into reality, lol.

that being said..I don't subscribe to the argument of the 15 hp rule. Do u know what I mean? Some guy dyno'd new cars on his dyno and found they were within 15 HP advertised HP suggesting that actual HP is around 15 over rwhp. That is in my o.

Most cars gain HP after a few miles on them but I have rarely whitnessed many examples of a well tuned car losing HP over time even after lots of miles. In that respect I will dare to say that the ls1's are in fact putting out alot more HP than advertised but based on even more factors including 0-60, QM times compared to weight ratios alone.

And the fact that so many cars show that 12-20% driveline loss. I would estimate those ls1's are at least putting out 350-380 depending on if yo uge ta good one are not.

 

[5spd GT]

Hehe, I like you 5spd but we may be butting heads there a tiny bit too . If I am sounding argumentative I don't mean to but I am giving you my opinions based on factual stuff I have read so its not just all opinion. if I get outta hand just smack me back into reality, lol.

that being said..I don't subscribe to the argument of the 15 hp rule. Do u know what I mean? Some guy dyno'd new cars on his dyno and found they were within 15 HP advertised HP suggesting that actual HP is around 15 over rwhp. That is in my o.

Most cars gain HP after a few miles on them but I have rarely whitnessed many examples of a well tuned car losing HP over time even after lots of miles. In that respect I will dare to say that the ls1's are in fact putting out alot more HP than advertised but based on even more factors including 0-60, QM times compared to weight ratios alone.

And the fact that so many cars show that 12-20% driveline loss. I would estimate those ls1's are at least putting out 350-380 depending on if yo uge ta good one are not.

Many ls1 guys will swear to you that they are in the range of 335-350 hp. It just depends on what trim level you get, like the ws6, ss, t-56 packages, ls6 intake or ls1 intake, etc.

Yep, you are right. The engine tolerances get a little looser and some "gaps" begin to show some friction reduction. However, after many miles you can begin to lose compression. Hence, the reason for "compression checks." Loss of compression equals loss of power in the vast majority of cases.

Pokageek - I like you too, but I don't want to sound "happy." I think it is a good discussion. I do not mean to come across rude either

 

[Pokageek]

Hehe ok. Yes, the ram air packages will gain HP that will not show on the dyno from the tunneling of air at speed > 25 mph. Amazing but that technology works. Pretty cool too! Great thread.

 

[final5-0]

Good discussion and good points by all

Again ... I'm no LS1 expert

I did stay at a Holiday .... I mean ...

I did look at quite a few Stock LS1 dyno pulls

I saw the 02's usually cranked out a few more than the 99's
but
There is a reason I did the 99

I gotta be able to have chart that is straight and not tilted in any way. It also
has to be clear enough to see all the tick marks.

I need those conditions to be able to make as accurate of a guess as I can
to arrive at numerical values for use in my Excel file

The 99 had a chart I could most easily work with

As I saw it ... the trend was quite a few of them made slightly more
than the 99 I used for our little comparison here but I could not work
with their charts.

Now about drive train loss

For most NA Street stick trans combos ...
15% is what I've seen to be a good ballpark value

Now ... about how miles effect a motor

Two things to deal with

1) Ring seal
2) Friction

If someone did not replace the air filter at regular intervals
or
Maybe they live in West Texas where the sand blows about a lot

You would most likely see they got more ring wear
thus
Loss of compression

As for friction ... race motors are set up loose ... to reduce it

A motor would obtain more clearance simply by the wear and tear
of more and more miles

Just trying to show its possible to reduce friction by miles
and
If the rings are still sealing really good

It would be possible to .....
make a good bit of power in spite of the miles

It would really depend upon how good the owner took care of it :Word:

Grady

 

[Dino Dino Bambino]

Stock T5 '94-'95 5.0's put down about 185-190rwhp, which equates to about 215-220 crank HP when you consider a 13% drivetrain loss.
The 6-speed LS1 Camaros and Firebirds put down about 290-300rwhp, which equates to about 330-345 crank HP when you consider the same 13% drivetrain loss. The early Camaro/Firebird LS1s were definitely underrated at 305 crank HP, and probably put out the same 345hp that the Corvette LS1 was rated for at the time (Corvette also put down about 290rwhp). The later Corvette LS1 was correctly rated by the factory at 350hp/375lbft 'cause that put down about 305rwhp/325rwtq.
A naturally-aspirated 347 stroker can put out as much HP/TQ as you want it to depending on which mods you choose, so you can't really make an apples to apples comparison with the stock LS1. You could use the LS1 as a benchmark to set your target HP/TQ level though, and that says a lot about how well engineered that engine really is.