lowblow143

I'm building my first b20v and I just wanted to ask some questions on my build.
first I have a

b20b short block from hmo. fresh rings and bearings. using low comp oem pistion.

gsr head from hmo with dual valve springs, stage 2 crower cams, stock intake manifold, 440 rc injectors

97 spec itr trans from hmo

I wanted to know how much horsepower I would be making? , I just wanted to put together a semi-stock b20v

DumpdEJ6

Probably in the 170-180whp range with the low compression pistons and stock IM.

vtecmaster85

i highly would doubt that. theres times where they'd see higher numbers with even type r cams.

vtecmaster85

the only way to know is to tune it.

k20z1ej1

gsr intake and TB will def hold it back above 7k rpm and those cams are gonna want alot more air than a stock intake can flow. Also its only 9:1 CR. id be surprised if it makes more than 185 on a dynojet

vtecmaster85

^^ i agree, i forgot about that part. you may wanna go with like skunk2 intake mani or even AEBS.

ontariorider

IMO it's worth it to spend a bit more on some YCP Pistons and arp rod bolts, for maybe an extra $500 in parts/machine work u will get the compression the cams need and with the rod bolts be able to safely rev the motor higher to take advantage of the cams as well.

An aftermarket IM and TB will be beneficial as well.

vtecmaster85

not really. i saw a dude make 210 on 93 octane with a stock block b20 vtec and buddy club spec 4 cams. the crower stage 2 cams have been pretty decent on stock-ish compression as they arent a very big cam but pretty decent. as long as he has good corresponding parts and a good tune it should do well.

DumpdEJ6

I made 199whp with LS/VTEC 1.8l block, b16 head, and 11.5:1 compression, Sk2 intake manifold, and Crower 402 cams. Granted I have 0.2 liters less displacement than him, but at 9:1 compression he's not going to make what I made at 11.5:1. I highly doubt your friend's pistons were stock B20 if he made 210 at the wheels.

vtecmaster85

thats good power man! but i have proof of my claim. also keep in mind he has 84mm bore vs your sub 83mm even with more compression. the whole reason for your compression is due to lack of displacement anyways.

k20z1ej1

Without arp rod bolts his engine won't last very long anyway. Unless he keeps revs under 7.5k, in which case it won't be making optimum power. Bottom line, it's a low comp, big cam, stock intake/tb b20v that can't rev much past 7k rpm. Op should get pistons, arps and a better intake. Unless he's cool with 170-180 whp.

vtecmaster85

thats also false about the limitations of the rod bolts of b20s. you shoud upgrade them or take precautions yes, but ive had a few and my friends as well( my tuner MirelesTuning) has ran many b20 vtecs without ARP rod bolts and theyve lasted revving over 8500 rpm. sometimes those without ARPs only revved to 8500 or so and theyve lasted. One of my friends has had his b20 vtec with stock rod bolts for over 4 years revving to 8500 rpm. also the crower cam are only 254/248 @.050 they arent that big but do the trick. Mireles also tuned a stock block b20 vtec with Skunk2 Ultra manifold and pro 1 cams on e85 and it made 208 and like 150 tq like 3 months ago or so. we simply dont know what it'll make he'll have to put it together and get it tuned to find out.

k20z1ej1

Yea, just noticed the graph you posted is a dynomite dyno. Not to get into a dick measuring contest, but dynomites are known to read higher - 5-10% from what ive seen. Also, some guys do get away with revving to 8k+ with stock rod bolts. Some guys dont. Its not a myth. When 20 or 30% of LS/B20vtec engines fail with stock rod bolts (or whatever the number may be,) its generally accepted that in order to have a RELIABLE engine, you use ARP.s

vtecmaster85

the b20 vtec with pro 1 cams which are smaller still made 208whp and 150 torque with a stock port head and default valve job, on stock block regardless of the attempt to discredit that setup due to a specific dyno you think is generous.

k20z1ej1

My intentions aren't to discredit your friends dyno results. I'm saying that when me and and dumpdej6 say it'll make 170-80 on a dynojet and you say it'll make more, that were talking abt two different dynos that are known to read differently among almost all tuning communities. I don't doubt that car made what it made. But I doubt op will make anywhere near 200-210 on a dynojet. They simply read lower than dynomites.

vtecmaster85

i didnt say itll make more. i said idk what itll make, he has to dyno it to see. i also never said he will make over 200. youre intentionally misinterpreting my words. i used the dyno to support that they can make power with big cams and dont need to build the block to make power.

DumpdEJ6

K20Zej1 is saying that dyno numbers aren't the same. Your friend's motor that made 210 on a dynomite dyno will probably make less than 200 on a dynojet dyno, because they are made by different manufacturers and dynos don't measure the exact same.

My 199whp might be 215whp on the dyno your friend measured his car on, or it might not, but it would probably be different; not because the power output changed, but because the measuring device did. If I measure something 10 inches long in inches and you measure the same thing in centimeters, and someone asks "Hey, how long is that thing?" I'm gonna say "10" and you're gonna say "25.4". We're both correct, just using different measuring sticks.

Really the only thing that doesn't lie is a drag race, and even then there is driver error, lane prep, suspension differences, tire compound, etc...I'm getting off topic here though. Numbers are just for bragging rights and might be able to give you a *slight* idea of what to expect when you mash the gas.

vtecmaster85

the thing is about both of you is you're set on being in the right. he only brought up " i noticed it was a dynomite dyno" when he called my bluff about a b20 vtec hitting 210 on stock block. so he went for that instead of just giving props. also, it still doesnt discount the fact the other b20 my boy tuned made 208 and 150tq on a stock port head and stock b20 block on e85, the other setup had a ported head and bigger cams. mireles also had his setup on stock block making over 200 with aftermarket cams and a few with ctr cams, including mine( ported b16 head and massaged ITR manifold).

thing is, the OP will need to be tuned to know what hes gonna make and the cams he has wont overwhelm the engine seeing that people are using BC4 and even pro 2s on stock b20 blocks and making over 200 whp. when he puts it together and gets it tuned, he will have to go from there.

DumpdEJ6

Well I only know the basics about cams and how they interact with compression and displacement, but at least from the conventional wisdom I've gathered on this forum he'd be overcamming his engine with those. That being said, as I said before, I'm no expert on cams. I'm not "set on being right", I just know that differences in dyno measurements are a thing and when we are comparing numbers from different dynos, that needs to be taken into account. Either way, that's pretty decent power from a stock bottom end B20.

Like you said, the only way for OP to know is to just do it.

k20z1ej1

i was gonna type a reply, but ^ pretty much sums up what I was gonna say.

lowblow143

thanks everyone for your guys info. I wanted to keep the stock gsr manifold for the secondaries . I'm not trying to fully build my motor . I just wanted a little more power than a stock ls. And wanted to know how much power my motor will make. I also have a golden eagle block guard cuz I heard b20 walls are weaker.. over all , with my build, I don't wana rev it to high cuz I want it mostly to be a reliable and a daily driver with a little more power. I just wana know the safe zone. Where I should set my red line, how much trq and hp I would be making

k20z1ej1

skip block guard. does more harm than good. b20 sleeves are fine for all motor, plenty of guys using them in 250+whp A/m builds. they only become a potential issue when boosted, even then some guys make 300+ boosted with no issue.

personally, i would keep revs under 7500 rpm. i know of a couple engines that didnt survive revving to 8k with stock ls rod rolts. some guys get away with it, some dont. its a gamble above 7.5k.

hp/tq depend on the dyno. a car might make 300 on a dynojet and then make 260 on a mainline and then make 340 on a dyno dynamics. they all read differently. i think your engine will likely be around 170 whp 140 torque on a DYNOJET. no one knows for sure until it actually gets tuned - that is the only thing any of us can tell you. anything we say is just a guess.