Turbo on an LS

[ssshhhh (_burn_)]

Originally posted by C32Bperformance
you got that 500 hp up in the revs, i was merely stating that your statement about 2k torque didnt mean anything in comparo to torque at 9k

Around here, ppl boost b16s like crazy, its the most popular motor.

Heres the deal, I used to think the ls was the way to go, its all i had my eyes on, i was gonna take the head i had and put the nice ls under it.

I watched b16 guys beat the piss outta their motors and have nothing break, even the boosted ones. Then I see the GSR and Ls guys boost their motors, and throw rods, and bend cranks an i began to get a little curious.

I found what i thought was the answer, the rod/stroke ratio. For a while i thought i was lucky in not having bought that bottom end already and have it junked after breaking it. For a while I started to see the b18 guys fall behind in the racing scene, and i watched even b16s with stock 8k revs beat out the b18s.

Now Im hearing differently again. So like i said before, tell me why the b18 bottom is as good as the b16, cuz i see otherwise here in tampa.

anytime you make a high horsepower engine somethings going to break. if you do it right....stuff breaks less often. all i know is....ive NEVER been beatin by a b16 period. shit. my daily driver n/a ls crx has knocked off 3 2000 si turbo's .
the ls bottom is as good simply because the internals can hold more boost and you dont have to rev the motor high to get power. bigger is better 99.9% of the time

[PWMAN]

Originally posted by C32Bperformance

Now Im hearing differently again. So like i said before, tell me why the b18 bottom is as good as the b16, cuz i see otherwise here in tampa.

If you don't rev over 7K the LS is just as strong. It wasn't meant to be revved, and it doesn't have to be. Most guys that do LS/VTEC try to scream their motors because they think they have too and thats why it blew up. It makes it's peak HP at 6300, so it makes no sense to rev over 7K anyway.

[C32Bperformance]

ok, i can see where your comin from with that, now heres my last arguement.

Im gonna do a little math here to hopefully prove what im trying to say, if it doesnt, then good for everyone cuz i learned somethign and you guys are right. Here goes.

Think about the extra torque an Ls is gonna make compared to the b16. Its about 12.6% (when comparing displacements).

Now lets set some torque standards, do we all agree that it doesnt matter where the torque comes from? aslong as the numbers are consistent with each other?

Lets say this particular ls has 250lb/ft of torque. That would mean the b16 under the same conditions would have 218.25lb/ft of torque.

The ls is going to rev 7000, and make its peak horsepower at 6300? Because of a lack of a dyno, we will put the torque numbers we currently have at the peak hp. Lets also say, that the b16 im describing with a 9k redline will peak at a meek 8200?

By means of TxR/5252=hp ::

The ls will make 299.8 hp. The B16 will make 340.7hp. I suppose thats the only thing left to be proven wrong and im an ls believer again. Thanks.

[PWMAN]

Peak torque is almost never made at the same RPM as the peak HP.
And displacement isn't the only thing that makes more torque, a longer stroke gives more torque also.

[C32Bperformance]

Because of a lack of a dyno, we will put the torque numbers we currently have at the peak hp

change what you like in the math, i think youll find similar results even when you correct everything... Im just not convinced, I see that the B16 is stronger.

[PWMAN]

Since the B18 makes it power at lower RPMs you can't really compare them the way you did. Because the B16 makes it's peak torque closer to it's peak HP. So my only answer can be just because it revs higher doesn't mean it makes more power.
When you said 12.6%, it's 13.1% actually. Because the B18B1 is 1834 cc and the B16A is 1595 cc. But that doesn't make much difference anyway, come out to 217.25 instead of 218.25. But anyway, this still doesn't take into consideration the stroke difference. So i really don't know what to say anymore, oh well. VTEC must also screw with some things too, when those secondary lobes kick in thats when the B16 finally begins to make some serious power, and of course the LS doesn't have this. So like I said there is just too many factors about this. I could plug everything into my desktop dyno, but of course that doesn't take into account the VTEC so screwed again.

[PWMAN]

If you want to compare it something with VTEC like the B18C1, thats peak torque is at 6200. Peak torque on a B16A is 7000. So take into account that it is only 1797 CC instead, thats 11.3% difference. So 250 Lbs for the B18 makes the B16 have 221.75. Take into account the RPM's and and you get 295 HP for the B18 and 295 for the B16. But the B18 will be faster cuz of the more torque.
I don't think rod/stroke ratio has much to do with how much power an engine makes, unless it's VTEC which allows huge cams to be run which gives you superior top end. So the fact that the B16 is VTEC totally messes up any calculations you or I may make to be able to compare it to any non-VTEC.

[C32Bperformance]

And in actuality, that comparison gives more hp to the ls than it would have, since it is non-vtec. It would have a little bit less torque up high like that. Thats as close as you can come in this forum on deciding which motor is better, but i honestly think if (_burn_) had put as much time and money and tuning efforts into a b16, he would be faster.

The b16 makes equal hp as the ls with much, much less boost. And that is not really even considering my original arguement, that it can in fact handle more boost than the ls.

[PWMAN]

Originally posted by C32Bperformance

The b16 makes equal hp as the ls with much, much less boost. And that is not really even considering my original arguement, that it can in fact handle more boost than the ls.

Well the fact that the B16 makes 30 more HP to begin with doesn't help. Also how is it that a B16 can handle more boost? Certainly not stock for stock, since the B16 has high compression, 10.4:1 VS 9.2:1. You can boost a stock LS 12 PSI, you can boost a B16 Probably 8 PSI. That 4 PSI is going to make that 30 HP difference up, plus the B18 will have more torque and therefore be faster.
And why do people think boosting a VTEC makes it better? NO it does NOT. VTEC causes so much valve overlap that at high RPM's it's hard to make boost.

[C32Bperformance]

I dont think however that the calculations i made on the previous post are very inaccurate. VTEC or not, any number of torque can theoretically be at any rpm with mods. So i put that 250lbft pretty lofty for the ls. but even then, you could just figure the hp at the peak torque rpm, which will be less than the peak hp rpm, and the b16 still is faster.

And im not getting into the arguement about how important hp really is. It just is, not peak hp, but hp in a grand scale. Torque needs to happen as fast as possible, and thats what hp is. Im sorry, i do not see it the B16 is stronger all the way.

[C32Bperformance]

And why do people think boosting a VTEC makes it better? NO it does NOT. VTEC causes so much valve overlap that at high RPM's it's hard to make boost.

Sorry buddy, thats wrong. You can ask any real engineer or tuner. VTEC helps no matter what. All thats happening is that some, SOME boost is being lost between overlap. You arent having trouble making boost. It boost just fine.

[C32Bperformance]

By SOME were tlaking the difference between 130% VE and 133% VE, gimme a break, the torque up in the high revs made possible by VTEC blows away any loss you might have from high overlap.

[C32Bperformance]

Oh and i understand that the compression on the LS is much more friendly to turbo, when talking stocker, but we arent, were talking hard boost, were talking tuning, drag racing. Compression can be changed...

[PWMAN]

There's no replacement for displacement

LOL

[PWMAN]

How is it that it say's you're offline but you are still replying?