B20 Turbo or B18 ls turbo

[tris416]

Hi I have a 94 civic ex. I was looking to build a diff motor for the car. I am stuck between a b18 ls turbo or a B20 turbo. I have heard the ls tranny is the choice for turbo and these two motors have the best compression for turboing. I was woundering what all would be involved to make these engines fit and what would be the best combo of parts and Internals for my car. Like for example I heard that the b20 intake manifold has to be switched for the hood to close. If you have any other sugestions to diff engines besides these two please post your opinions. I was looking into Ls/vtec and the Crvtec but got pushed away from them. Im looking to run at least 20 psi and I do know that I need sleeves but, also what other parts should I look into investing to make this work. Thank you for all your time.

[GScivic7]

The only problem with turboing a b20 is the cylinder sleeves. They are a one piece design and are prone to getting hot spots which can warp and damage them. If you resleeved the B20 it would be the way to go. About the same hp as the b18, but more displacement + boost = a lot of torque.

As for being able to run 20 psi, new sleeves, forged pistons and rods. That will get you started.

[sageuvagony]

man... all the power we crave for only a daily driver.

[tris416]

I was woundering if I would need to do any head work for the boost? Like new cams, valve springs, and/or retaners? I know for example anything that increases hp before the turbo will give more power in the end result. For example like a port polish. Is it also worth investing in a new intake manifold or throtle body at all? I wasnt sure because of the fact that your forcing air into the engine if the intake or throtle body would have that much of an impact or not. I have also heard that the b20b head is the same as the ls head is this true? If not which non vtec head would be the best to use? and by using a diff non-vtec head is there anywork involved by placing it on? Thx for all your help.

[GScivic7]

the B20B is essentially a bored out B18, same head and all. You don't need to do any headwork, but I've seen boosted cars gain close to 20 whp with turbo cams, valve springs, retainers and new cam gears. It all depends on how much you have to spend.

[tris416]

Right now Im looking at getting a sleeved B20b block with eagle rods, forged pistons (would 8.5:1, 9:1 or 9.3:1 be better). A b18 head with stage 2 port and polish, stage 2 turbo cams, Aem cam gears, Titanium retaniers and rev hard valve springs. Skunk 2 intake manifold and a bigger throtle boddie, aem fuel rail and bigger injectors. Also a stage 3 clutch raceing pulley and litened fly wheel. I was wondering also if I can use a b18 a/b crank or not? I can not find a b20b crank? Also what other fuel upgrades besides bigger injectors and a fmu would you recomend? I know there is cable ls trannys are there any hydro ls trannys? If not what all is involved to make a cable tranny work witht the hydro setup? With this setup what turbo would you recomend for 20psi or a lil higher? Thanks for all your time. I really apriciate it. Thx

[GScivic7]

there are hydro ls tranny's. Any 94 and newer uses the hydro tranny. You can use a b18 crank, there is no problem there.

As for fuel upgrades. Sounds like you want a lot of boost, I would go with at least the RC 550cc injectors, a fuel pressure regulator, Walbro 255 lph pump and Hondata not an FMU. FMU is good for boosting up to about 10 psi after that you're going to have reliability issues cause it will run rich as hell.

go with either the 9:1 or 9.3:1 pistons. You could boost more with the 8.5:1 pistons, but you are giving up a lot of power that is already there.

As for the turbo, I'd go with a Precision SC61. Or the Garrett Disco Potato.

[tris416]

I found a b20 vtec motor. The guy says that it will produce 220+ horse power and in the right car will easily run 12's or maybe even faster. Is this true? Block- b20b4 block
decked,
honed
hot tanked
Bored to 84.5mm
11.3 wiseco strutted and coated pistons
Shaved, shotpeened, balanced rods with ARP rod bolts
Balanced and micropolished crank
Entire block is blueprinted and set at factory bearing specs with factory honda bearings
should be around 11.9 compression with milled head

Head- 2000 GSR head.
Milled .030.
blended bowls and stage 1 polish.
unshrouded valves from 81mm to 84.5mm
Integra type r intake valves
All new seals
Full valve job
3 angel
swirl polished
Portflow valvetrain and titanium retainers
LS vtec conversion complete ready for oil line

Cams- Civic type R cams. Skunk 2 intake manifold mugen replica valve cover
ARP HEAD STUDS lightened aluminum crank pulley Brand new factory replacement plug wired and bosch plugs. skunk 2 adjustable cam gears all new seals and gaskets
adjustable fuel pressure reg with gauge

I am sure there is much more. this motor was professionallt biult by lyons technical machining. this motor has NEVER been started it is a fresh build

He says "This motor will produce an easy 220+ wheel horse power which will easlily put a civic hatchback into the low 12's. MY friend has the same setup running lower compression and he ran a best time of 12.31 in a EG hatch. So for around the same price as a full turbo kit you can get something that will spank any 4-500 hp turbo honda!!!" Is this true lol. Also would this engine be able to handle any boost saftley if so how much thx.

[GScivic7]

11.3:1 compression isn't a very safe CR to be boosting with. How much does this guy want for this motor? It really is a beast of a motor too.

[tris416]

He wanted 2800 dollars. But he allready sold the engine. You have helped me quite a lot on the stuff I didnt know about, and this is helpin me go in the right direction with buildin a turbo engine. I have one last question, I have been pushed away from ls/vtecs and cr vtecs, but in comparison to a ls turbo and a lsvtec turbo the lsvtec on some can have 100 less hp but more torque. So All in all is the ls/vtec TURBO worth the money and mantince? Also do you know what all is involved and what parts would need to be diff. Thx this is the last step before I can start buyin parts to build my engine thx.

[GScivic7]

I personally don't like the LS/VTEC, B20/VTEc conversions, all I read are horror stories on the net and one of my friends who actually has the B20/VTEC has had problems up the butt with it. You will get more power from one of those frankenstein motors, but I would just screw and use the money to build up a B18B or B20 block to handle more boost.

I don't remember exactly what goes into one of those conversions, but I do know that you need a VTEC head obviously, you have to plug a hole in the block or something like that, and you need either an adapter for your oil filter, or run a T from you oil pressure unit to feed the head oil.