Let's talk about VTEC

[sohcslammer]

O.k. - I really only want to hear from the people that know what they are talking about, and you know who you are.

My friend is building his 2001 LS integra. He was going to do the LS/VTEC thing, but after talking to many people on this site, we have decided to build the LS. Acording to Brian and Bill, Bill's LS is putting down around the same power as a type R. Now also according to Brian, VTEC is kinda pointless because all it does is switch to more agressive cam lobes. So by putting aggressive cams in the LS it is like having VTEC all the time. (Yeah, that was the best way to describe it. I KNOW what VTEC is.) Shitty gas milage, but it should put down some decent power right? Now we get to the question/debate part. By putting cams/valve springs in his LS motor will he see the kind of power he wants, or is it better to go VTEC? How high can you rev a LS motor assuming you have done the proper head work?

As of right now, the plan is this -
Crower stage 2 cams
Crower "race" valvesprings/retainers
"Chipped" ECU (Later replaced by Hondata)
Port job
I/H/E

What kind of power will he see? Is this a good idea?

Brian/Bill - you told me that Bill wasn't even reving his LS motor high enough to get all the power out of his cams. Does he have valvesprings? What kind of cams? Thanx guys -
SOHCSlammer

 

[E_SolSi]

there is one more important step you forgot.... pistons

you need to get your compression up .... bill is running JDM B16 pistons (about 11.1:1)

bill is still running the stock LS ECU so he cant rev to where the crower 403s hes running really start making power (about $200 for an ECU and the problem will be solved) hes running the crower springs and retainers
he isnt putting out ITR power yet but with a little more work he will be

 

[sohcslammer]

But you COULD just chip the ECU to get a higher rev limiter right? And I know the pistons are important, but he's not trying to run 12s or anything. What do you think about decking the head? Useless? Just go with the B16 pistons right?

 

[lsvtec]

Someone has to have flowbench results for the LS head VS a B16 head. I would be willing to bet that the VTEC head (in stock form) will consistently flow better than the LS head. This can be over come with some prot work. The last issue is not really an issue for a race car, fuel economy. VTEC rocks because it allows you to stay on the small cam and a fuel efficient map while you are in town commuting. You won't see that on the LS.

 

[khrisb]

Is this right??? VTEC is just a sham? You can just run more agressive cams and "be in Vtec" time???

Bill or B, can one of you elaborate???

 

[sohcslammer]

Originally posted by khrisb@Sep 8 2003, 02:47 PM
Is this right??? VTEC is just a sham? You can just run more agressive cams and "be in Vtec" time???

Bill or B, can one of you elaborate???

Well think about it. VTEC is just shifting your cam lobes to a more aggressive grind. By putting in aggressive LS cams, it is LIKE being in VTEC all the time. You won't get to come out of VTEC though, hence the shitty mileage.

 

[khrisb]

Shitty mileage, scmlitty mileage! If I cared about gas mileage, I'd drive that ugly honda hybrid. The only reason I don't drive domestic iron is because they're ugly and too big. Just doesn't fit me... I guess I'll have to rethink my whole engine build-up...
Hmm...
I'd still like that elaboration from Bill or B.

 

[SleEPeR_CRX]

HOLY FUCK HOW DID I MISS AN LS BUILDUP THREAD! anyway man, im the guy u need to talk to about this 1, i weighed the LS/Vtec, the LS/Turbo, and have no decieded to go built LS, do to my financial situation. #1, LS/Vtec will suck UNLESS BUILT FLAWLESSLY, im serious. i put down 15.00's in my CRX with an LS with i/e. theres a 93 CX hatchback civic, with a BUILT LS/Vtec running 15.3? why? cause the guy built it like a fucknig moron, he has everythnig JE pistions, IM, cams, springs retainers, sleeves, blueprinter balanced. the only downside is LS tranny, but hes almost 3 seconds off where he should be. dont build the LS/Vtec, unless u want to spend the time and $$ tuning it perfectly. as for an LS buildup, alot of people will say alot of things that it cant rev, or it has no HP possibilies. which on part is right, it will never keep up to a b18c or b16a on the freeway, duh. but it will pull its ass all the way to the end of 4th if built correctly. turbo, if u have the $$ is the better way to do this. if u can afford it go LS/Turbo, but if thats outa ur budget, like for me, then follow my 6 step program to LS beauty.

#1, I/H/E, dont cheap out here b/c this is the breathing of ur car. get a good CAI, 4-1 header to take advantage of the high rpm's u will run with new cams, and a good 2.25" exhaust.

#2, good tranny. if u can afford it, go b16 tranny, the gearing will own the track, but own u on the highway(4800RPM at 65mph) get a solid 12-14 lb flywheel, and a good clutch that can hold the torque an LS puts down( i reccomend an ACT HD clutch and pressure plate with 55% more gripping power)

#3 Head, its true, the LS head does FLOW LIKE ASS, u have a b18b which is better but can be improved, a small Port and polish will free up alot of torque and HP, and with honed IM and bored throttle body, u will have a great flowing source of air.

#4 now, u said crower stage 2. there is no such thing, the cams u want are called
Crower 403's with titanium spring and retainer kit. u have to order the springs and retainers cause teh cams are to big to use without them. these are the biggest and best priced cams for the LS, they make big differences to the HP and HP curve of ur LS, with a peace HP at 7300RPM, making around 14hp to the wheels over stock cams. while the new springs and retainers go in, its my suggestion to get a 3 angle valve grind done, to ensure proper seal and breathing of valves.

#5 now u need an ECU that makes power throughout those rev's. rechip ur LS ecu, to make more power at the 5000+ range ( the 403's start to make more noticable power after 4300 RPM) get the Revlimit taken off, and fuel cutoff moved to around 7700 RPM.

#6 get good spark plugs and wires to help ensure a good spark, also if needed get a fuel pressure regulator to adjust to the more air, and better spark of the engine.


This is relatively cheap to do. i am almost done this exactly buildup on my 1991 LS engine, and hope to dyno it as soon as its broken in. ive spend around 3000 canadian on all this, so i know it can be done for relatively cheap, and will put down supprisingly impressive results. the last step for max power is

#7, b16 pistions with rods and rings. shot of nitrous( colder plugs for nitrous)

this is pretty much all u will need to go fast, if u need faster, get a new IM, throttle body, injectors. but all that will add up fast, and is not super necessary to make ur LS go fast, it will just slightly improve the performance. hope i helped man, if u have anymore questions PM me and we'll talk.

 

[saturn_boy96]

i think vtec has yet to reach its full potential. having two different cam lobes gives you two entirely different power curves.

you could theoretically create a cam that is so nasty it could not be engaged until 2,000 rpm because it wouldn't idle, couldn't you? and that cam could be setup to make power from 6,500rpm to 12,000 rpm just like your idle(low lift cam).

why hasn't any one done this?

 

[MaliWho97]

Good write up man. If you decided non vtec, you will get bad gas mileage like they pointed out, and if you go too aggressive on your cams, you will notice a rough idle, I don't think anyone said anything about that.... Toda makes "VTEC Killer" cams for those who are full race and don't want to wait for vtec. If it is going to be a street car, go vtec or do a little more forgiving street cam for the non-vtec head.

 

[sohcslammer]

So, it's looking like it's going to be -

403s
springs/retainers
port no polish
B16 pistons (if I can talk him into them)
chipped ECU
i/h/e

Sweet. Is 160 at the wheel a little TOO optomistic?

 

[SixtySecondAssassin]

Originally posted by SleEPeR_CRX@Sep 8 2003, 03:20 PM
go b16 tranny, the gearing will own the track, but own u on the highway(4800RPM at 65mph)

i have a y21 and im at almost 75 in 5th gear at 4000rpm. you shouldn't give out 2nd hand knowledge.

 

[E_SolSi]

bill is running crower 403s in his LS setup
the car idles fine
and he never got it tuned

he could have run the 404s with no problems

if you want the car to idle well get the fucker tuned

 

[xj0hnx]

Originally posted by SixtySecondAssassin+Sep 8 2003, 09:59 PM-->

SleEPeR_CRX

@Sep 8 2003, 03:20 PM
go b16 tranny, the gearing will own the track, but own u on the highway(4800RPM at 65mph)

i have a y21 and im at almost 75 in 5th gear at 4000rpm. you shouldn't give out 2nd hand knowledge.

No doubt, I don't even hit 5500rpms till 100mph.

 

[98integrals]

Originally posted by E_SolSi@Sep 8 2003, 04:02 PM
bill is running crower 403s in his LS setup
the car idles fine
and he never got it tuned

he could have run the 404s with no problems

if you want the car to idle well get the fucker tuned

werd. unless you are using you car more for road racing where you will have extended time high in the rpm range 403 or 404s would be a much better choice.

this is basicly the same thing i was going to do with my b18b. LSi w/cams.

i will find some dynos of ls w/403/4s and post them asap

 

[khrisb]

Originally posted by 98integrals+Sep 8 2003, 05:48 PM-->

E_SolSi

@Sep 8 2003, 04:02 PM
bill is running crower 403s in his LS setup
the car idles fine
and he never got it tuned

he could have run the 404s with no problems

if you want the car to idle well get the fucker tuned

werd. unless you are using you car more for road racing where you will have extended time high in the rpm range 403 or 404s would be a much better choice.

this is basicly the same thing i was going to do with my b18b. LSi w/cams.

i will find some dynos of ls w/403/4s and post them asap

please do. I'm intrigued. I've been thinking about the whole engine build-up thing all day. cheaper Ls or way more expensive Gsr... It was gsr, but now I'm thinking...

 

[posol]

here I am

I would be willing to bet that the VTEC head (in stock form) will consistently flow better than the LS head.

I agree. the LS head flows like shit. nothing some port work and valve jobs can't fix. Bill's head has a 3-angle valve job on it as well.

but what flows even more shitily (is that even a word?) is the fact that he's still running the OEM intake manifold, OEM exhaust manifold, a ghetto rigged intake, an ecu with the wrong mappings, no vafc or any tunable device of any type, cams that aren't degreed properly due to the lack of cam gears, and he still put out the same torque as an ITR, and roughly the same horsepower at 6-6500 as, thats about when the fuel kick off starts to happen from the LS ecu.

From an Ass dyno perspective, the car gains 200% more balls at about 5500 rpms.
Unfortunately, the car is just about to run out, and there's not much head room due to this, but let me tell you, above 5500 pulls like a bat out of hell.

Back to the topic at hand.... VTEC. it acts in the same manner-- it swiches over at roughly 5500 rpms. bills cams are larger than ITR cams in both duration and lift. and thus, the low end is suffered a little bit. its FAR from a dog off the line, but if it had a small cam profile (read, the first lobe on a vtec system) it would have much more torque off the line.

As for the tranny, he's running the LS tranny. Honestly, it's not as long as everyone makes it out to be. my d16z6 tranny is longer. 3rd gear is over by about 85-90, where as i can hit 103 in my z6 tranny in 3rd.

 

[98integrals]

Originally posted by BlueTeg@team-integra.net

I know a few of you guys were interested in what type of numbers the Crower 403 cams made in an LS. I finally got them put in this weekend. Here are the results:

150 whp @ 6500 rpms
125 lb/ft tq @ 5300 rpms

Baseline Run(red) = aem cai, comptech header, 2.25" carsound cat, comptech exhaust = 132 whp, 121 tq
Dyno Run 007(blue) = same setup as above + Crower 403 cams, Crower valve springs, B&M fpr set at 40psi @ idle, aem cam gears (intake +1, exhaust -1), SAFC


Here is a dyno plot of the cams untuned vs. tuned

Baseline Run(blue)-untuned = i/h/c/e, Crower 403's, Crower valve springs, B&M fpr set at 40 psi @ idle, timing at 16 degrees, aem cam gears (0,0) = 148 whp, 123 tq
Final Run-tuned(red) = same setup as above except: aem cam gears (intake +1, exhaust -1), SAFC tuning = 151 whp, 126 tq

The guy who tuned it did an excellent job with flatening out that nasy dip in the power curve that you can see from 4300-5200. It dyno'd pretty well, powerwise, without any tuning what so ever putting out 148 whp. The guys that worked at the shop said I could have hit 155whp, but I told the tuner that I was more interested in fixing that midrange dip than boosting the peak power, he said no prob. And that he could probably pull out more power in both the midrange and top end.

and here is what crower claims:

 

[posol]

bill put 148 on the un=-degreed set-up i posted above

 

[aphex301]

my friends with v8 mustangs, camaros, and trans am's always give me funny looks when i complain about gas mileage in my civic...

my car before my civic was a 350 5.7 4bbl 86' firebird.

im never gonna stop compaining about gas consumpion, cause im a cheap ass.

its all about the SOHC VTEC...