nonvtec

Upon further review I have to admit an LS makes a lot more power in the low end, vtec however, spools a turbo like a mother so :P

Inquisition

Don't type if you don't know what you are talking about. The LS makes more torque based on cam and head design. Small intake ports allow high velocity at lower rpms. Also because the cams are relatively mild they produce that midrange power. End of story. No one is saying one head is better than the other. I'm simply taking the stance that "just add a vtec head" is not always the correct stance and in many cases will call for a total over haul of your setup(new transmission, new manifold, new turbo housing, different wastegate, ect, ect, ect). I understand this is homemade turbo and there is a certain amount of the geterdone mentality, but it should be coupled with correct theory. Just throwing parts together "because it works" is half assed.

PS: The LS's powerband at 6500 is still better than the b16s at 6500. Look at the torque or horse power value. The LS's is higher. If more torque = worse powerband, then is up down and left right? But OMG the torque is dropping off. It must be a piece of crap.

Blaast, I'm not talking about 50 different engines. I'm talking about taking a turbo setup, putting it on a b18b1 long block and putting it on the dyno/street/whatever and then taking that same turbo setup and using a b16 head on a b18b1 long block. Compression ratio gets figured into the engine flow the same way as any other modifcation to the engine. Its figured into the VE. The slight gain in compression with the b16 head will not increase the VE more than the cam/head design of the b18b1 head at the same 4000-6000rpm. LOOK AT THE TORQUE CURVE.

BLAAST

I sense a strong urge to "end the story" and kill the topic for good but talking that ---- is what the forum is about so there's no "enough said"... I hope!

I have seen some t3/t4 with 0.63 turbine spool up super quick on LS VTEC engines. All that before the vtec kicks in. We all agree that other factors may come into play but definitely, You'll never spool up a 0.63 a/r turbine that quick on a stock b18b .

dirtygsr94

you say that head flow doesnt matter? your crazy what good is the ve if the head isnt efficent enough to push that air out of the motor quickly? the improved flow allows the air to exit the motor at a higher volocity therfore reducing overlap isnt that more correct? isnt that why a better flowing head=more power why elese would people even bother getting a port and polish job if it had not much effect

z1guy

WOW, i think everyone saying "go vtec head swap" is thinking about this the wrong way. first off, an LS stock bottom end isnt the same as the gsr/b16 bottom, so revving an LS/vtec to 8500rpm isnt a good idea. so that kills that theory... secondly, like stated, bumping compression w/ the swap still wont add enought VE to equal that of an LS setup, killing that theory... sure extending the powerband will net more HP, obviously, but wont change the lag/response/spool at all. the CORRECT answer in this situation is solely based on VE, which one is higher, obviously the LS because of the lower rpm based cam profile and intake ports. IN all honesty, if you are running an LS trans, swap it, if you have any other trans and it still seems like alot of lag (shouldnt take long to hit full boost w/ any other B trans) then you honestly just need a smaller turbo.

sohcpwr

so you'd rather spend an equal amount of time/money into a b16/gsr trans instead of doing the head swap? Get the ---- out of here. If you wanna be different and make crazy horsepower on non vtec engines, that is fine. But you cant deny which is better

z1guy

im not saying do the tranny swap to reduce lag, just to increase overall performance of the car in general. acceleration would increase dramatically therefore ultimately decreasing 1/4 mile times (traction pending). i can decide which is better in my opinion, the LS is a better street setup where the rpms arent always way up in the powerband, and tq on demand is needed. not just high HP when i rev the **** out of it. look at any two stock dyno charts B16/b18c vs. B18b now determine where you spend most of your driving time at, whichever one has more TORQUE in that range is the best selection for you. overall higher HP doesnt mean ---- if you only spend 25 percent of time in that range. thats why all out race cams (vtec killers if you will) arent used in many street applications, how many people drive around at 7000rpm? now you dumb ----, take your b series vtec and race an LS same tranny of coarse, and see how hard you pull him until you hit vtec

nonvtec

Flow only matters in high RPMs, I completely changed my position on the topic, that LS power curve kills the B16's. Both of those motors with B16 trannies and the LS motor would have a faster quarter I reckon.

Jcushing

yeah man i have no idea what point your trying to make with those dynos. they both make the same peak power but the LS one is making a ---- ton more tq. no i assume one has a b16 tranny and the other a LS so it would be pretty easy to conclude overall they would have very similar acceration numbers. one has more tq and less gears the other has less tq and more gears.

seriosuly guys though a LS vtec will make more power than a straight LS but theres a reason. it wont make more power than a LS with turbo cams and a good port job and you can get that for what a vtec conversion costs. its all personall preference. with THAT i think the thread should die... to many comparisons of things that are way different from each other.

it seams like every non vtec motor thread no matter what the topic is instantly turns into GO VTEC YO but all he wanted was a faster spool.

z1guy

cfm flow does matter in the whole rpm range, but port velocity matters more, and when the cams are designed for upper rpm range, the lower rpms suffer, thus giving the LS the advantage on the street. think of it in terms of duration instead of peak output. the LS has MUCH broader powerband than the vtec's do. everyone is just on the MAD VTAK JDM HIGH HP AT 22,000rpm BANDWAGON, and cant exept the fact that a cheaper motor is infact the greater design... oh, and by the way, im a hardcore SOHC vtec guy, so dont think this is a "i got an LS so i think its better situation". its truly the technical side.... yes, a track only car with a vtec head will outperform the same car w/ a non vtec head, but only because on the track the extended rpms will carry the vtec head farther w/ the same amount of TQ... PERIOD, end of discussion, unless someone still disagrees.