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good ls/vtec info
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Author:  phan [ December 17, 2003 ]
Post subject:  good ls/vtec info
I suggest you check out these sites:

http://www.c-speedracing.com/howto/lsvtec/lsvtec.html

http://www.angelfire.com/sc/thuspeed/lsvtec.html

http://www.geocities.com/MotorCity/...437/lsvtec.html

the c-speedracing site goes through most of the salient points about the process of putting the combination together.

the key to this setup is WHO does it ....not the parts you should get which is what most novices focus on only, not realizing the impending headache they will face from an improper install.

you need to find a very good machine shop locally who is precise and has a good rep for doing things to spec dead-on (like blueprinting) with aluminum heads and blocks (not just iron domestic blocks). You have to
plug the VTEC oil passage in the VTEC head (usually welding the plug in is better than just using a bolt plug) and then machine the plug down flush with the cylinder head's deck surface. Secondly, since the LS block dowel pins and the VTEC head's dowel pin holes are not aligned, the machine shop must redo the dowel pin holes by slotting them to line things up properly.

The main problem with this setup is, if machining & installing are done improperly by an inexperienced or incompetent shop, you will end up with oil leaks and coolant leaks, since the ducts for oil and coolant in the
head and block are not aligned up...they were never meant to be put together at the factory in the first place and they have to "make" them fit with adjustments at the machine shop.

I always tell LS owners that you can get much more power reliably ,if you invest in a turbo and getting the correct anti-detonation parts , instead of running an LS VTEC.

To run faster than a GSR or ITR with i/h/e, you must upgrade the pistons for higher compression in the LS block. My friend Chistian Gaines runs an LS VTEC with 11:1 CR and makes over 185 peak whp with Type R cams. Chris used to visit us over at Superhonda and gave me good advice.



Most beginners mistakenly think the VTEC head allows them to rev higher.

The rod ratio in the LS VTEC is still the same as the LS...a low 1.54. This does not help your cause in revving higher. I explain why elsewhere, if you do not know what rod ratio means and it's implications on the redline. Beginners often think that the head and VTEC gives them a license to rev higher, when in fact, the rod ratio is what allows you to rev higher safely and reliably. The head just breathes better and VTEC allows variable valve lift/duration to get a peaky powerband in a 4 cylinder engine and at the same time, get decent driveability in the low-mid rpms....that's all...having VTEC is only one part of being able to rev higher...NOT the entire reason.

These concepts don't just apply to the 1.8L LS VTEC . You can apply them to a B20 VTEC which is a CRV bottom end or block (also has the exact same rod length & stroke as the LS!) with any Bseries VTEC head (it also needs the rear dowel pins aligned and the head oil duct shut by a machine shop). You don't rev a stock block 2L B20 VTEC past 8000 rpm either.


If you know of a good local shop then you may still want to look into
doing it...I also recommend http://www.drtracing.com who has done several of these reliably.

question
....but ls/vtec engines tend to put out more hp and torque than a
regular vtec engine. it makes for a good all motor set up
/question

the LS bottom end has a lower rod ratio than the GSR or ITR bottom end.

as the rod ratio on a naturally aspirated (i.e. No Boost) engine becomes lower or shorter, low-mid rpm hauling power increases.

you see the peak torque shift to a lower and lower rpm, as the rod ratio drops. This is probably why Honda chose a shorter rod ratio with a higher displacement on the integras compared to the civics.

As you decrease displacement to 1.6L on a civic , peak torque , as an absolute value, becomes smaller and you have to rely upon higher rpms to generate horsepower, instead of depending on torque. So the civic gets a longer rod ratio because of where it's powerband will be located (in the higher rpms).

The 1.8L , with more displacement, makes more torque and has a lower "hauling" or "pulling" powerband. It gets a lower rod ratio.

Please be careful about making statements about the 1.8L LS VTEC peak torque compared to the 1.8L VTEC peak torque. You hear this statement that the 1.8L LS VTEC makes more torque (assuming the same cams , redline, header/ cat/exhaust, and static compression ratio in both engines). In most cases, unlike this myth of more torque in an LSVTEC, the B18C actually makes as much or more peak torque..BUT AT A HIGHER RPM: it's rod ratio is higher or longer than the LS VTEC's. The key here is: the VTEC engine with a better rod ratio can happily rev all day at a higher rpm than the LS VTEC over the years. You can push a stock B18C bottom end to 9000 rpm as long as the valvesprings are upgraded. You can't go to 9000 rpm on a stock LS block's rod ratio.

<3 tuan & temp
Author:  Tb Fivel [ December 18, 2003 ]
Post subject: 
very biased write up.....and a few flaws too.

to say an ls/vtec does not make more torque than a b18c is rediculous.with an 89 mm stroke as aposed to the gsr 87.2mm stroke, how can you possibly say that the torque is not there? if it isnt there, someone is tuning your motors horibly.

as far as not being able to rev the motor to 9 grand, i rev mine to 8,500 daily, (and i mean daily...a tank of gas will last me 3 days on occasion) and thats only cause my R cams stop making power about there due to my ghey stock gsr intake manifold not being able to provide enough flow that high up. we've built motors that run as high as 9.500 regularly, we crack pistons due to compression before we spin rod bearings or throw rods in general.

and to say any honda motor in general on boost is more reliable than an ls/vtec is ridiculous. thats why i drive my ls/vtec'd integra DAILY, and my boosted prelude rarely sees the street.

about the best line i read in this entire write up, is not what you put in the motor, its who puts it together. what you put in plays a big part, but youc an have all the best parts, but if put together by someone who does not know what they are doing, it will not last.

and just for refference, my motor has been in my car for about two months now, and i have close to 5,000 miles of straight abuse on it. no problems yet. this is a 12:1 ls/vtec with ALL OEM HONDA parts with the exception of my valve springs and retainers.
Author:  phan [ December 18, 2003 ]
Post subject: 
Tb Fivel wrote:very biased write up.....and a few flaws too.

to say an ls/vtec does not make more torque than a b18c is rediculous.with an 89 mm stroke as aposed to the gsr 87.2mm stroke, how can you possibly say that the torque is not there? if it isnt there, someone is tuning your motors horibly.
so you mean to tell me if i built:

1. ls/vtec - ls bottom, b16 head
2. poor man's type r - gsr bottom, b16 head
3. fully built b18c1 - gsr motor

that #1 torque > #2 & #3? if you read the post, it says, "In most cases, unlike this myth of more torque in an LSVTEC, the B18C actually makes as much or more peak torque..BUT AT A HIGHER RPM." it wasn't saying that there is NO TORQUE in the ls/vtec or that the b18c1 makes TONS more torque than it, it was just saying you can get just as much or a bit more torque with a gsr bottom/or gsr motor.
Tb Fivel wrote:as far as not being able to rev the motor to 9 grand, i rev mine to 8,500 daily, (and i mean daily...a tank of gas will last me 3 days on occasion) and thats only cause my R cams stop making power about there due to my ghey stock gsr intake manifold not being able to provide enough flow that high up. we've built motors that run as high as 9.500 regularly, we crack pistons due to compression before we spin rod bearings or throw rods in general.
again, if you read the post, it's talking about r/s ratio and the side load on the cylinder walls. on a STOCK LS BOTTOM, revving high puts a lot of pressure on the cylinder walls due to the poor r/s ratio. putting a vtec head does not immediately mean you can rev to 9k rpm, as you obviously know. i'm glad you take your motor that high, and since it's built, then i don't see the problem with it. good for you, want a cookie now?
Tb Fivel wrote:and to say any honda motor in general on boost is more reliable than an ls/vtec is ridiculous. thats why i drive my ls/vtec'd integra DAILY, and my boosted prelude rarely sees the street.
well let's see...
motor 1
b20 boosted...just for the sake of argument, we'll do this easily. sleeved block, eagle rods, je pistons (we'll say 8.5:1). ported/polished head, maybe camshafts...but nothing major. redline is not raised, so the stock powerband/redline is still utilized.

your quote
"and to say any honda motor in general on boost is more reliable than an ls/vtec is ridiculous"

motor 2
ls/vtec...ls bottom, b16 head. stock rods, pistons, non-sleeved block. the b16 head is stock...cams, valvetrain, etc.

i'm sorry, but i'd much rather the boosted b20 as my daily driver than the ls/vtec motor because the boosted motor would be much more reliable. to say that any boosted honda motor is less reliable than any ls/vtec motor is not only incomplete, but ignorant.
Tb Fivel wrote:about the best line i read in this entire write up, is not what you put in the motor, its who puts it together. what you put in plays a big part, but youc an have all the best parts, but if put together by someone who does not know what they are doing, it will not last.
the only thing we agree on.
Tb Fivel wrote:and just for refference, my motor has been in my car for about two months now, and i have close to 5,000 miles of straight abuse on it. no problems yet. this is a 12:1 ls/vtec with ALL OEM HONDA parts with the exception of my valve springs and retainers.
hm, ok? all i ask is that you read (and comprehend) posts completely before giving your opinion on them.
Author:  Tb Fivel [ December 19, 2003 ]
Post subject: 
your kidding right? your gonna compare a GE sleeved b20 with forged components to a stock ls bottom end with a stock b16 head? thats hilarious, (and id still take the ls/vtec for a daily).

i love how you compare a completely STOCK ls bottom end and completely STOCK b16 head to a poor man'sR and a fully built gsr. why not throw in a d15 for comparisons sake? wait, i think well add in my neighbors go-ped. oh wait, i still think my set up makes more torque than a poor mans R, and probably more than a built GSR (even though thats a very broad range due to the fact that "built" could mean a variety of things.

can you explain to me how swapping my ls slugs for b16 slugs changes the amount of cylender wall pressure in my motor, cause i didnt know that changing pistons affected rod ratio. and when is having all OEM parts considered built? i prefer oatmeal raisen if your offering.


b20 boosted...just for the sake of argument, we'll do this easily. sleeved block, eagle rods, je pistons (we'll say 8.5:1). ported/polished head, maybe camshafts...but nothing major. redline is not raised, so the stock powerband/redline is still utilized.
this one is good, so good i had to quote it. GE sleeved block, eagle rods, JE slugs, PandP head and cams. nothing major of course.

how much experience do you have personally with boosted honda motors. i have plenty, anything on boost sucks! for daily driing purposes, its not practical. oil leaks, heat soak, creep, just a few of the head aches. and dont worry, well add cams and leave the rest of the valvetrain stock since we wont be reving any higher. "JE piston, id like you to meet mr b20 valve, you guys will become good friends ove rthe next few days"
ls/vtec...ls bottom, b16 head. stock rods, pistons, non-sleeved block. the b16 head is stock...cams, valvetrain, etc.
i can build 6 of these for the price of your b20, and your still not boosted!

and please, dont compare apples to oranges, it just doesnt work. lastely, all i ask is that you open your eyes for 2 and a half seconds and read on some of the stuff from someone who has built plenty of these motors. ive built boost motors, ive built N/A motors. ive got a fully built h22 on boost, i know how it goes. ive got my teg and its oem ls/vtec. i still drive the shit out of my teg and can park it and walk away wthout worrying unlike my prelude which i have to pop the hood after every run and make sure everything is ok.
Author:  phan [ December 19, 2003 ]
Post subject: 
Tb Fivel wrote:your kidding right? your gonna compare a GE sleeved b20 with forged components to a stock ls bottom end with a stock b16
head? thats hilarious, (and id still take the ls/vtec for a daily).

i love how you compare a completely STOCK ls bottom end and completely STOCK b16 head to a poor man'sR and a fully built gsr. why not throw in a d15 for comparisons sake? wait, i think well add in my neighbors go-ped. oh wait, i still think my set up makes more torque than a poor mans R, and probably more than a built GSR (even though thats a very broad range due to the fact that "built" could mean a variety of things.
i was pointing out how you threw in no details...i was being sarcastic, obviously.
Tb Fivel wrote:can you explain to me how swapping my ls slugs for b16 slugs changes the amount of cylender wall pressure in my motor, cause i didnt know that changing pistons affected rod ratio. and when is having all OEM parts considered built? i prefer oatmeal raisen if your offering.
when did i ever say changing pistons altered r/s ratio? i said ls motors put more cylinder wall pressure at a higher rpm, we'll say 8500, than an itr motor. when did i ever say OEM parts = BUILT motor?

Tb Fivel wrote:
b20 boosted...just for the sake of argument, we'll do this easily. sleeved block, eagle rods, je pistons (we'll say 8.5:1). ported/polished head, maybe camshafts...but nothing major. redline is not raised, so the stock powerband/redline is still utilized.
this one is good, so good i had to quote it. GE sleeved block, eagle rods, JE slugs, PandP head and cams. nothing major of course.

how much experience do you have personally with boosted honda motors. i have plenty, anything on boost sucks! for daily driing purposes, its not practical. oil leaks, heat soak, creep, just a few of the head aches. and dont worry, well add cams and leave the rest of the valvetrain stock since we wont be reving any higher. "JE piston, id like you to meet mr b20 valve, you guys will become good friends ove rthe next few days" (that was actually funny, i give you that much).
ls/vtec...ls bottom, b16 head. stock rods, pistons, non-sleeved block. the b16 head is stock...cams, valvetrain, etc.
i can build 6 of these for the price of your b20, and your still not boosted!

and please, dont compare apples to oranges, it just doesnt work. lastely, all i ask is that you open your eyes for 2 and a half seconds and read on some of the stuff from someone who has built plenty of these motors. ive built boost motors, ive built N/A motors. ive got a fully built h22 on boost, i know how it goes. ive got my teg and its oem ls/vtec. i still drive the shit out of my teg and can park it and walk away wthout worrying unlike my prelude which i have to pop the hood after every run and make sure everything is ok.
i agree with the fact that honda motors on boost CAN suck. but you have to agree with the fact that ls/vtec motors CAN suck too. i still don't see how having a STOCK ls block and throwing a vtec head on it, revving to 9k ALL DAY as you say you do, can last at all...that just like doesn't make ANY sense. and no, you couldn't build 6 motors for what i paid for my b20... :)
Author:  Tb Fivel [ December 19, 2003 ]
Post subject: 
well considering i spent less then a grand on my "built" ls/vtec, i could most likely build six "stock" ls/vtecs for the price of your still non boosted b20.
Author:  .saint [ December 19, 2003 ]
Post subject: 
we dont need the drama because of some info on a motor buildup. maybe some facts were wrong. and maybe some were misread/worded whatever. but take the bickering to PM's please, or better yet take it off the site. i dont wanna see this place turn into a drama pool like most car forums around. thanks.
Author:  sleepinonacreeper [ January 06, 2004 ]
Post subject: 
i read this and threw up. sorry. i like discussions, but not silly arguments.
Author:  Nikku [ January 07, 2004 ]
Post subject: 
flow charts for B-series VTEC heads
Image this is a chart of a B18C(5)5 head plotted against a toyota 2ZZ-GE head, the chart is posted for reference of the B18C(5) head, you will need to plot it on the following chart or compare the numbers to see how the C5 head is against other B-series VTEC heads

Image this is a flow chart of a B16a head VS. a B18C(1)
Image B16a vs. H22a vs. F20C, you can see how the b16a head fits into the grand scheme of things here
Author:  Nikku [ January 07, 2004 ]
Post subject: 
some other general information

http://www.hondaswap.com/forums/index.php?showtopic=11

here is a kit made by eagle, it looks quality and i have heard good things about it so far

http://www.robearracing.com/pd_golden_e ... l_vtec.cfm

here is whats included for the lazy people who don't want to go look

"FULL VTEC CONVERSION SYSTEM

- We now have a Full Vtec Conversion System for people that want to use an LS/VTEC or B20/VTEC set-up.
- This kit is the easiest and most complete way to supply oil to the head without any machining required and is very clean and reliable.

The kit includes:
- 1. Golden Eagle Vtec Conversion Sandwich Plate with a -6AN fitting for the plate and head.
- 2. -6AN steel braided teflon hose for oil supply
- 3. Golden Eagle Vtec Conversion Dowels for proper alignment of the head and block without machining
- 4. 1/8 NPT tap and plug for the oil port in the head
- 5. Golden Eagle worked factory head gasket with any bore size and dowel holes opened for any application

-When we say " NO Machining " we mean that there is no reason that anyone cannot do this kit in their own garage. - The only thing that must be done is tapping the head for the plug .
- The VTEC line and fitting all use existing ports with no need to do anything else.
- Sold as a kit with full instructions.
- Individual parts can be purchased separately."
Image Image go here for more of their products

http://www.goldeneaglemfg.com/
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