First of all i have searched for an answer to this question for about 3days now so please dont flame for that.
Anyways, to my questions. Im deciding whether or not i want to go ls-vtec or just boost a regular b18b. The only problem that i have heard of that is unreliable with ls-vtec is that it does not have the "oil squirters" that vtec motors have because the block was not made for it. therefore it is not as safe to spin the motor up to as high of an RPM that a b18c or any other stock vtec motor could. (please correct anything i say if it is wrong ) Besides this flaw in the ls-v are there any other things 'wrong' with the combination of a vtec head on a ls block? Also with FI on a ls-v do any new problems arise with the motor since it is not a stock vtec engine?
I know that if i stick with a b18b it is probably a safer and more reliable setup, especially with a turbo. However i know the ls-v will make considerably more power (enough for me to want to do it) than the reg. b18b, but im not sure how reliable it would be compared to the b18b. I'm aware that tuning plays a LARGE role in the life of an engine and how solid it will run, when i get either setup and the turbo i will take it somewhere to get tuned on either a Hondata s200 or AEM EMS.
(All questions are asked concerning a completely stock ls-vtec with b18c head and stock b18b in mind. Thanks for any input.)

 

i HAD ls-turbo...at stock I dyno @ 225hp.
i went out and bought a portflow b18b head and gain more than 20hp
my final dyno numbers at inlinepro was 252 hp at 8psi on t3/t4b

so i recommend getting a better flowing head to optimize the power

good luck

 

dang, quite a nice power gain. How much $ did that run you?

 

bought the head used 600

not a bad gain for the bucks...now if u crank up the boost, you'll notice even more

 

Very nice gain for the $
Anyone else have any light to shed on this post?

 

i want to know about a FI ls-vtec. i've heard alot of people run them and make more power and run higher psi than my turbo gsr. anyone know anything on rod stroke ratio and if cylinder wall contact is likely to occur on an ls-vtec?

 

LS/VTEC as long as they are built right are great for boost. You just shouldnt rev it too 8000 very often. The bottom end is made for the higher redline. GSR cams love boost and b18c head is much better flowing!

 

I've thought about this a lot, i figured. Why not just up the boost and get (basically) the same result. Its not stressing the motor any more to get HP from a better flowing head or from increased boost, you follow me? There would be a small efficency loss because the air doesn't flow quite a freely, but i'd guess this would be a few HP at most. Some people will disagree, lets hear their side of the story.

 

I'm going to go against the grain here, but bear with me.

We all know that AT BEST an LS/VTEC setup will be as reliable as a stock LS... that's at best. (READ: $$$) An LS is always going to be either more reliable, or as reliable as an LS/VTEC. If you're looking for 300 horsepower, you can make that on an LS. Turn up the boost and you'll get the horsepower you want.

LS/VTEC only makes sense financially if it costs less than just buying a B18C. If you want a reliable LS/VTEC you're going to spend more than you would on a B18C. LS/VTEC is not the way to go, just turn up the boost... period. Turning up the boost costs you $0.

 

Thats true and I agree with you for the most part there. However, you would have to run a higher psi of boost on a regular ls motor to acheive a particular goal of hp (lets say 300whp or so) than you would on the ls-vtec correct? and wouldnt that make the ls motor a bit more unstable than the ls-vtec or would the differences in the amount of boost recquired to reach that goal not be that significant? (remember this is all taking into account that the motor's internals are completely stock.)

 

I say make decisions based on your goals. Just dont make the decision to get a B16a. Also a bone stock LS block can make 300whp or more so there isnt really a need to get the vtec head. sure its nice, but hey, were all working on a budget here. Spend the extra money you saved instead of going ls/v and invest it on piston, rods, and studs. then you will be reliable and good for way over 300whp.

 

depends on how much your power goals are...it also depends on if u are staying stock bottom end or built bottom end... LS/VTEC built right will always make more power than a GSR at the same amount of boost... A built LS/VTEC can take 9000rpm reliably..there are lots of people doing that on here... I wouldnt do it on a stock bottom end though... If u want to be reliable and u are building the motor, u can always machine oil squirters into the b18b block or u could always just run a b18c motor with an ls crank and ls rods...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Grubb &raquo;</TD></TR><TR><TD CLASS="quote"> wouldnt that make the ls motor a bit more unstable than the ls-vtec or would the differences in the amount of boost recquired to reach that goal not be that significant? (remember this is all taking into account that the motor's internals are completely stock.)</TD></TR></TABLE>

No, it wouldn't. Boost isn't what makes a motor "unstable". It's not a matter of being unstable with the LS, it's a matter of what the piston/rod/sleeve combo can handle. A stock LS should be good till 300 with good tuning (more with PERFECT tuning). The LS/VTEC may get there with less boost, but you'll spend more to get there and you really won't get better results. Like I said, the only time that comes into play is when you're maxing the motor out with however many hundred horsepower that would take.

If you weren't boosted, it would be a different story. There's nothing to turn up when you're N/A so the LS/VTEC will make more power hands down.

 

Ok, i see what your saying. Thanks for the input MadCow much appreciated .

 

how about a nice b20b turbo?? wouldnt that make MORE power than an LS turbo?

Couldnt a B20 Turbo make more than an LS/Vtec turbo?

 

Stock ls vs. b20 turbo would produce roughly the same amount of power. The b20 coming out ahead of course though because of its 2.0 displacement. However the b20's sleeves are much weaker than the ls. But that is getting into a whole different discussion thats already been beat to death.

 

then how about b20/vtec?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thrty8street &raquo;</TD></TR><TR><TD CLASS="quote">then how about b20/vtec?</TD></TR></TABLE>

it will still have weak sleeves, the b20 is the EXACTLY the same block as the b18b/a just bored to 2.0L

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thrty8street &raquo;</TD></TR><TR><TD CLASS="quote">then how about b20/vtec?</TD></TR></TABLE>

There is alot of info. on b20 and b20vtec just search for it, most of the threads are recent so have at it

 

alright i got it then get a b18b bored to 2.0 and THEN go turbo OR VTEC

 

i plan on doing a LS/Vtec turbo setup in my Civic HB..... Just keep it simple and use good parts and tune it and it should treat u good..

My setup is very simple.....

B18b Block
Wiseco 9.8:1 Compression Pistons Stock 81mm bore
Eagle Rods + ARP rod bolts
ACL bearings
Endyn Block Girdle

B18c Gsr Head
EF-1 valvesprings
EF-1 retainers
Stock GSR or Crower 402t cams (not sure yet)
AEBS head studs
JG intake manifold w/ 68mm TB
780cc Precision Injectors
Golden Eagle fuel rail

Turbo Junk:
InlinePro Cast Manifold
Precision Sc61 or Sc63 (not sure yet)
Tial 40mm WG
Tial 50mm bov
Spearco 26x8x3.5 FMIC
Custom Downpipe
Custom IC piping
E-Cutout

Extras:
Golden Eagle LS/Vtec conv kit
Aeromotive FPR
Walbro 255 in-tanke pump
Hondata stg2
Maybe a small shot of nitrous (40-50shot)

 

I have a stock LS/VTEC in my 99 Si. The reasons why is because I wanted more displacement, lower compression and more torque. The setup is really low budget and I haven't had any problems so far at 15 psi. As far as I know, the oil squirter's are nice to have but aren't really necessary.
Here's the link:
http://www.gtrmotorsports.net/bios/jaybio.html

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Grubb &raquo;</TD></TR><TR><TD CLASS="quote">Thats true and I agree with you for the most part there. However, you would have to run a higher psi of boost on a regular ls motor to acheive a particular goal of hp (lets say 300whp or so) than you would on the ls-vtec correct? and wouldnt that make the ls motor a bit more unstable than the ls-vtec or would the differences in the amount of boost recquired to reach that goal not be that significant? (remember this is all taking into account that the motor's internals are completely stock.)</TD></TR></TABLE>

PSI isn't what is hard on motors, its peak cylinder pressures. You gotta realize upping boost and VTEC do the EXACT same thing, get more air into the cylinders. HP from a better flowing head isn't any better than horsepower from upping the boost. The answer is clear to me, why spend money on vtec when you can have the same results with as good, or better reliablility. hope that helps.