fluentshift

i recently bought a b20z and lately ive heard its a bad engine to boost because the sleeves are to thin. i was wondering how it would do all motor or how much it would cost to sleeve it or should i just keep my b18b1 in my ef? and also i was wondering if i could get some more info on the b20z thanks!

beatngyou27

B18B1 is decent for boost depending on ware. the pistons are flat enough for adding some boost and the sleeves are not thin like the B20. I would keep the B18B1 and just do a head gasket and slap some boost. You wont be running High boost without a re-sleave. you can safely run about 10lbs on B20. depends on your budget and what your looking to do.

Head work head work don't forget the head work and you'll get some good gains

Freemananana

iTrader: (3)

Ew, suggesting PSI has anything to do with safety.

The B18B1 is a good motor to boost. Low compression is forgiving and it can handle some power on stock sleeves. I would go with ARP head studs if you are boosting the motor. You can run high boost without a re-sleeve though. You can run 100 lbs through a T25 1G turbo, probably blow the turbo to pieces, but it won't be making any power after about 18 lbs and will only cause damage to itself. With that said, at 18 lbs you probably will be seeing 250 whp or so. But if you went with a larger turbo, like the T3/T4 57 trim Garret turbo I have, 18 PSI will see 450 HP or so. Which can definitely cause some bottom end damage. Still probably safe on stock sleeves though.

And the B20Z head is a good high flowing head. Works a lot like a VTEC head (flow wise). It's a great motor, would I swap the B18B1 for it, I don't know. The turbo will be more fun than an all-motor build if you are setting aside a decent budget. I'd turbo the B18B1 and skip the B20Z.

beatngyou27

what are you talking about?

Freemananana

iTrader: (3)

PSI is 100% dependant on the turbo, therefore should not be considered when determining what an engine can handle. Torque is what damages engines, torque is also directly related to horsepower. With this said, horsepower should be used when determining what is safe. Not pounds per square inch.

beatngyou27

True but but OP's question wasn't about HP he was asking about boost on a B20 and the sleeves. the condition of the engine is what would better determine the amount of Boost/HP he can handle. I'm not quite sure I believe Boost is a byproduct of HP. it's more l like HP is a byproduct of Boost. and 10lbs is 10lbs. saying 10lbs of boost is different depending on where its from makes no sense. if 10lbs from one turbo is greater then 10lbs from another sounds like someone isn't running 10lbs. stress on the turbo is a factor though a tiny turbo is working harder to put out that 10 compared to a big one.

so if you have a bullet proof block and you can run 30lbs of boost and you can run 10 on another engine. the more boost as long as your engine is built for it 30lbs would create more HP. that's why people use Boost gauges not HP gauges.

I'm not understanding your theory on this.

beatngyou27

to me your theory is like saying me running in a dead sprint for a quarter mile has nothing to do with the amount of oxygen I can intake but just about my muscle strength.

and my reference of safely running 10lbs was directed to just the B's not every engine.

Freemananana

iTrader: (3)

Boost isn't a byproduct of HP. I didn't say that. I said HP is a by product of torque. Torque is also what breaks things in conjunction with heat. 10 PSI from one turbo IS NOT the same as 10 PSI from another turbo. That's why you are confused. You need to research CFM and how it relates to boost pressure. A tiny turbo and a large turbo on 10 PSI has nothing to do with how hard the turbo is working. You realize how a turbo system works, right?

Here's a quick tip. It has a lot to do with surface area. Imagine a water hose. You leave it open and it's a large hole. You are only getting 5 PSI of water coming out of it. You stick your thumb in front of it, you are now getting 20 PSI of water. The pressure increased. In order for the big open hole to have 20 PSI you would have to turn the hose up more. Therefore it is using much more water to get up to 20 PSI because there is a larger hole. Same thing with a motor, except instead of how much water, it is how much horse power.


Nex thing, you build a block for the HP, not PSI. 30 PSI through a T25 turbo might get 300 HP. 30 PSI through a 72mm Turbo (like the big supras use) is 1000 HP. You are telling me 30 PSI should be the same for those turbos.

You didn't read those quotes very well, 10 PSI has nothing to do with how much power the motor makes. That metaphore of yours was also horrible. Your respiratory system is basically one giant muscle group. I guess you must hold your breathe when you run a sprint.

EsotericImage

iTrader: (8)

^^
Your analogy on the head is wrong. The non vtec heads are some of the worst flowing heads with exception of the P8R which flows close to a B16.

Getting back to the OP's question, As a owner of a few b20's its the cylinder pressure that will crack a sleeve. Theres plenty of B20's on boost that work fine. Its all in the tune so theres no detonation.

Detonation in addition to cylinder pressure will crack a sleeve. The B20 sleeves are a siamese design which is different than the B18B. The B18B also has more CR (9.8) then any of the B20 blocks.
Theres a few that have pushed B20 stock blocks/bottom ends past the 300whp line with success but most of the time 300 at the crank is the limit.

If you already have a B18b, I would just boost that. Flow rates go out the window when your forcing air into engine.


google B20 P8R and youll see the HT thread with more on the B20 block

Freemananana

iTrader: (3)

I thought that's what I was talking about. I thought the B20Z head was the P8R? I had just recently talked to someone about that head and how well it flows. That's why I compared it to the VTEC B-series heads.

If I was wrong in what I said, I am sorry for spreading bad information. But I may have actually just been a tad confused and got something mixed up.

Dark_Teg

B20's do not have thin sleeves. They crack between the sleeves when boosted. They actually look thicker than B18 sleeves.

Psi has nothing to do with HP. Saying a given engine can handle X amount of boost is wrong.

Having said that what you can and cant do depends on your goal. If your goal is 270-280whp buy the appropriate sized turbo and by all means turbo the B20Z. If you want more power than that I would go with a B18.

Freemananana

iTrader: (3)

I had forgotten about that last part. If you goal is pre-300 HP, the B20Z will net you some more torque than the B18B1 will. But I'd still rock what you've got.

EsotericImage

iTrader: (8)

The other heads are the P75 heads on the B18/B20b/z that are normal for those blocks. Finding a P8R is like finding a unicorn at this point in time since they stopped being made back in the late 90's

Freemananana

iTrader: (3)

Thanks. I guess he just had a P8R head that he was using on the B20 block. I just connected the dots and I was wrong. Guess I get that for assuming.

fluentshift

thanks guys! i think im just gonna stick with what i have a build it over the winter thanks for making my decision easier!

Deetz

This is true...people that say they are, don't know what they are talking about. The sleeves are just as thick, if not thicker, just mounted differently.

Boosting a B20 is all in the tune. btw, here's a pic of a B20 with stock sleeves

fluentshift

by the way guys quick question non related to the b20z is anyone aware of a site or a place around indiana that sells peformance parts like pistons rods etc. thx and whats a good brand ?

Charlie Moua

iTrader: (3)

keep in mind turbo size & how much boost your running. More boost means IAT will probably hotter & therefore have greater chance of detonation.


B20 turbo is fine. IMHO, this is how i would seperate the limits of the b20 stock sleeve

1) stock block 100%
a) small size turbo (evo 16g)
12-15psi 250ish whp pump gas
18-24psi 280-330ish whp e85

b) medium size turbo (50-55trim)
10-12psi 250-270whp pump gas
14-16psi 300-350whp e85


2) b20 with css block modification (rods & piston, stock head)
medium size turbo (50-55trim) = 400whp @ +18-20psi or so ...pump or e85
larger size turbo (+60trim) = 500whp (really depends a lot of stuff) +25psi psi e85


these are pretty medicore guesstimations ment to provide rough idea. Don't make the mistake of using some exceptional builds as the bench mark to go by.

GL

RoseFuneral

yeah the b20 having "thin" walls is a bunch of crap. its just designed differently. i love my jdm b20b in my 93 si hatch. really fun engine. they respond better to bolt ons then any d series. if tuned, all the better.

a b20 with a vtec head is a really fun ride. i decided i really didnt need to turbo mine because it makes good power already. but some people have an addiction for speed and need to turbo lol. i just wanted a reliable, quick, fun to drive, car.

Sl0w_S4

So do you guys recommend resleeving the block? Block girdle, or a block gaurd? Just because I have a b20z and want boost later kn down the line. IF I do boost later one its gonna be around 6-8psi but the turbo might be pretty decent size "have one off my mustang" unless I come around a better deal.

wshuculd

I have a boosted b20 vtec that's been going strong for about 2 years. Stock bottom end never touched. It puts down over 350whp on 11 psi. Get yourself a good tuner and you'll be fine. I should add I've had the block for about 6 years it was b20 with boost,then b20vtec supercharged for a few years then all motor. Now it's boosted

wshuculd

Let me add my set up right now is on pump gas

Sl0w_S4

If you dont mind me asking who tuned your car?

wshuculd

Pb @ suja 1 he was in Chicago area now he's in Nashville

Freemananana

iTrader: (3)

What did he tune it with, S300, neptune, chrome?