thefastguys

I have a b18B1 block. B18C1 Head. Fully Ported the correct way. full rebuild.
I have ALL the supporting mods Necessary to do a turbo build HOWEever. I do not have the turbo. because I need to decide what I need to get. Heres the goal. Hence why I'm in this thread right now asking.

12.3.1 compression long block
10 lbs of boost on E85.

What turbo...being efficient volumetric efficiency wise would i need to breath well all the way to 8000rpms. (car is a 5 speed)

340 WHP is the goal

TheShodan

iTrader: (14)

For what power level? You could get a GT17 for that? Budget? flanging system? use of the car? (you want full pressure of 10psi by 2000rpms? Won't happen in 99.9% of the cases without it being VERY small)

Need more to even BEGIN to work with that kind of compression.

thefastguys

the car is going to be a Street fighter. Im wanting conservative BUT extremely responsive Hp. on max boost (10lbs) with e85 I want around 400 hp. crank. (the engine is already 240crank horse now N/a
the car is going to have a c02 sprayed intercooler. Iffff I have to opt for quick spool and not being perfect on very top. ill do that. Im just looking for a turbo to run 10 lbs of low CFM boost for quick spool.

Budget. Dont matter... im just looking for a turbo and a manifold.
I want the power to come on AS VIOLENT as possible.

TheShodan

iTrader: (14)

On a 2.0 litre, 400whp from 10psi of boost pressure reached in full by 2000rpms. Won't happen. No matter what fuel used on that displacement. High static compression helps to get to an effective dynamic compression can only go so far.

I've been doing this a lot of years. You're not the first to attempt this particular endeavor, and you won't be the last. But at that rpm range, it will not happen, regardless of budget.

C02 in the intercooler doesn't increase "spool". That only cools the charge for inefficient intercoolers that can't exchange air correctly. Only will cool the charge a bit, but won't "spool" the turbo up any faster. Only a twin charged setup (combination of supercharger and turbocharger) or a shot of nitrous will do that.

Change your boost/rpm goals related to your wheel hp, and then you're looking at something more mission capable.

About 11.5:1 for 320whp on the right setup can reach about 8-14 maximum pressure by about 3100-3300rpms realistically on a 2.0 litre. Anything more and you'd still have to change timing from your 12.5:1 as though it were 11.0:1-11.5:1 anyway.

thefastguys

ok...I understand your knowledgable, But you did not answer any of my questions sir.
I Know that Co2 spray does not affect spool times...but only to increase efficiency.

I want a turbo for my setup to spool up extremely quick at low RPM's and provide 10 lbs.
I'm wanting to rev 8500 and 10 lbs spooled at low rpm on 12.3.1 static comp.

so If i may ask again to all you viewers. What LOW cfm turbo would you recommend that supports 400 crank hp and is efficient from 5 ish lbs to 15 lbs

sanman000719

welcome TFG you will not find anyone on this forum that has the skill set that theshodan has, and he is the man we all come to ask questions of becuase of that.

what he says is gold, and he already explained how to spool fast at lower engine speeds.

nos brah

rs250nut

What about using a variable vane turbo for instant boost, you may be limited by top end power.

OneBadTurboCRV

That isn't extreme compression. Hell, there is a build or two on here right now with 13.5:1+ and the one has 600whp at that...

Either way, "TheShodan" has spoken.

GEN2 LS

iTrader: (3)

why do you want to run such low boost? Most turbos don't reach their efficiency range until 13-14psi on average. Also why are you even bothering running 100 octane if you are going to be running E85 as well? You will not be able to make 400whp on 10psi on any turbo that spools up to full boost @ 2000rpms it's not possible. You are trying to make the power per pound of boost of a larger frame turbo but retain the spool characteristics of a smaller frame turbo which just isn't going to work. I think you need to grasp a better understanding of how a turbo setup works.

wantboost

iTrader: (2)

New guy came in thinking he was hot ****

Denied

TheShodan

iTrader: (14)

Because 99% of the engine managment systems can't work the vanes properly based upon the parameters he's asking. And, by the time he comes around to paying the average $4k for the turbocharger (the used ones were considered defective by the manufacturers, as they don't repair them if damaged, and people try to sell them for cheap in the hopes that you bring up this very idea )

For a single turbocharged application on a Honda, yes, that actually IS considered to be one of the more extreme example of a turbocharged application for the parameters that he's asking for. (A 400whp "low boost" [aka BIGGER than expected 60-70lbs/min] Higher compression turbocharged application) on a 2.0 Litre engine)

If you want to take a crack at solving his initial problem with this, my old friend, be my guest. Calculate, hypothesize, and educate away.

@thefastguys: I'm sorry I did not answer your question specifically.. Its because it cannot be answered. Change your parameters, state a budget, then its possible to look at alternatives. But 400whp under 10psi of boost pressure BY 2000rpms on a 2.0 litre? Not physically possible, or at best highly unrealistically improbable.

Charlie Moua

iTrader: (3)

lol
Not laughing at what OP is trying to do.
Just funny how OP definition of "high cr" wasn't really high.


OP, believe me.... I use to be like you.
I bought a apexi P13 turbo kit (basically with 2,000 miles on it in 2002)

On of the other htech og members had this turbo kit on his stock LS.
Stock 6500rpms redline & his turbo maxed out making 260whp at 18psi. full boost @ 2400rpms. & his car was setup for autocross, so overall pretty balanced

I though i had the perfect master plan. lol





I was going to put this on my stock gsr, but failed to recognize that bvtec heads flow more than LS heads & with 2,000 more rpms, this tiny turbo would be screaming for it's dear life to make 250-270whp.... even if full boost came at 2800-2900rpms.

just because your car gets the lead off the line, you better have a linear powerband to fend off your lead in 3rd & 4th, otherwise you'd easily be passed.

for a street fighter you'll want something that packs a decent punch in your midrange but not completely flat-line up top.
You have 8000rpms to play with, stop thinking you gotta make all the power at 2K. that's just dumb.

OP you say you want a Bvtec turbo that get's full spool by 2K.
It will NOT be any kind of street-fighter
If you haven't, go drive any factory turbocharge car as they are designed to have nearly instant tq for daily driving. What first comes to mind are the VW 1.8T.... quick power but falls flat right after it reached full boost, power peaks out well before 4500rpms.





If I were to do it again with limits of 300whp I would go with:
simple LSV (gsr cams + itr pistons + arp rod bolts)
custom manifold + evo8 / evo9 turbo with stock 2.5" cast elbow downpipe.




If I were to do it again with limits of 400whp I would go with:
simple LSV (gsr cams + itr pistons + arp rod bolts)
inlinepro manifold + GT3251B + 3" dp



but honestly, unless I'm broke, using it for daily driving or hate/scared driving it to the max...i don't see anyone wanting to be limited 300-400whp.

wantboost

iTrader: (2)

So jelly of that kit

thefastguys

OK, I am not implying ANY disrespect to anyone in any way indirect or Directly. 12.3.1 compression is considered high compression because stock is around 9 typically and when your going over 3 full points above stock application. The engine is NOW high compression Because It is MUCH higher then the stock static before modification. Just because 12.3.1 compression isnt high to you. doesnt mean Its normal compression in retrospect.

hell. If i wanted. Id get custom pistons. clayed relieved pistons milled heads. custom valves and run 14.1 with 10 lbs of boost through a hx40 with c16 race fuel mixed with 5% nitro methane and run 20 lbs. BUT im not. THIS is my gas getter. My lowest Hp car I will ever own. and probably the slowest. BUT...however I want this to be Peppy and Super fun to drive. I want it responsive and Be efficient. I cant stand people who are like oHHH my car makes 500 hp with a 60mm turbo that doesnt spool up untill 5500 rpms or later and THEN blame why they lost on MAssive boost lag issues and they didnt launch right or blah blah blah.

Ok, since im not going to change my overall application. and Im not changing my goal for hp.

new objective relative to question.

How much boost will i have to run. to achieve 400 hp on a 1.8 liter with 12.3.1 static. and WHAT turbo will best suit my needs in terms of (quicK) as possible spool time and be efficiant at high R's

theshodan. I thank you for your advice and everyone elses input. I just have specific questions that need specifid answeres pertaining to what my options are Runnning THIS setup. Thanks again guys.

Btw. This is MY first honda build. All my import buddied convinced me to do a honda for fun so Im doin it.

thefastguys

charlie...great advice thank you. wrote down your suggestions. thanks man

i see what your saying. the stroke on a b18b is the same as the b20 and that mixed with high compression makes for great low end grunt and mid range power. I need a turbo to bring the mid to top end alive. since my static setup before postive vacuum hits will keep me haulin *** at low r's. so boost isnt really neeeded that early... never though of it like that.

Kozy.

You sound like a total dreamer TBH. Why 400hp? Why full boost at 2k? Why 12.5 compression? All for a street racer? If you were to tout this idea on a UK forum, it would get brushed off for sounding like the wet dreams of a school kid. Sorry if you're not, but that's what it sounds like.

Regardless though, I thought I'd chime in on the this bit, as I've got a thermodynamic model that might give some insight.

Based on 400hp, you'd be aiming for about say 300lbft at 7k, that's about 410psi BMEP. Looks like 21psi will do it.

Going on TheShodans limits above (11.5, 320whp at 8-14psi), I'd estimate the real world limit of peak cylinder pressure to be in the region of 900-1100psi, let's call it 1000psi.

Your 410psi BMEP will be looking more like 1300psi with the ignition at around 20°. You'd have to knock the ignition timing back. My workings, (not complete admittedly as I can't account for valve timings yet) suggest that even with no ignition the PCP would still be 1100psi.

I have no idea about E85, but to me, from a design standpoint, this just looks totally unworkable on gasoline.

Lower your limits. If you want responsive, lower the boost, you don't need 400hp in a street car.

If you absolutely must have 400hp for racing on the freeway, forget high compression. You can make more power with a low compression, and the responsiveness won't matter for freeway pulls.

Those same specs tell me that 400hp could be done at 9:1 with 26° ignition and PCP of 1000psi. I.e it would actually run comfortably.

If you're not willing to compromise on the CR, then 14psi will see you at the ragged edge of 350hp.

ETA: re read the OP

I see the 400hp goal was on E85, in which case 1300psi might be sustainable.

At 10psi that's sitting around 1000psi on gas, however that's only about 340hp, pretty far short of this arbitary 400hp target.

thefastguys

You make ZERO sense KOZY. pleaSE Take your ill experienced advise and go elsewhere. YOUR telling me i cant reach my goal of 400 hp on 10 lbs? with my static, disp. AND tuned on e85.

I thought i heard it all. I thought honda tech was the place to go. Obviously its full of trolls who just wants to cut you down without any real logic backing it up.

YOU WANNA ask me what a high static ratio is gonna benifit me? whoa.... iF u understand basic engine dynamics. HP all boiles down to Fuel. AIr and cylinder Pressure. THAT is it. if i can make the same hp now on 10 lbs? with e85 why would I dump my static to 8.5.1 and have to run 20 lbs to get the same hp on 93?


Please....someone give me advice on the turbo i need to run with realistic ideals and logistics. thats all i need advice on. I DO not need advice on what compression to run or what gas. Just what turbo do i need to run that will net me 400hp as a end result and spool nicely.

Kozy.

I edited the post, if you hadn't seen it, to say I misread and that 1300psi could possibly be sustained on E85. On gasoline though? Slim chance.

Right, like thermodynamics? Pretty sound principals last time I checked.

Yea, I'm asking you. Do YOU know how fuel, air, compression and ignition timing make power? Do YOU know where the limits are for cylinder pressure? You've just said my post doesn't make sense, so it sure doesn't sound like it...

Kozy.

I did, got shot down. Apparently this kids engine build doesn't obey the laws of physics as we know them.

thefastguys

Kozy, i apologize for jumping the gun. at first i was like...wha... But yes Kozy I understand your point. BUT the reason i chose such a high static is so Its not doggy under 4000 rpms. 400hp isnt a huge number first off. and i think its conservative knowing how much power you actually could make on e85 with that compression. but. i dont. i want low boost and extremely efficiant. I dont wANNA BE THAT honda that takes 3 years to spool.

so again...lol Im trying to find a turbo that fits my needs. its gotta support just 400hp and have relatively quick spool times.

Kozy.

OK, no worries.

I can't help with selecting a turbo for your needs, I'm just interested in the science and thought I'd share my musings.

DirtyDA9

I want to see your 240hp dyno sheet of your NA LSVTEC.

OneBadTurboCRV

"TheShodan" - What is going on bud, need a hug? We all know I do. HAH! Somebody beat me to it... (even though I wouldn't have wasted my time going that far).

OP - Something along the lines of a GT3076R. I am sure "TheShodan" will rattle off 1,672 other turbos, but 50-60 lbs a min is where you want to be. You need to forget all this BS of PSI like it matters and STOP acting like Hondas spend a lot of time below 3-4k RPM. Unless grandma is driving, most kids drive 60mph in second. It is called rev it up, dump the clutch, and go.

TheShodan

iTrader: (14)

Still won't make 400whp by 2000rpms, under 15psi of boost pressure.. even with THAT compression. If there were 1,672 other choices, I would have stated it already in my other "wasted" posts.. Won't happen. But he's waiting on someone else to confirm what he thinks he knows on this application. At this point it doesn't matter what I say.

I could splather off a lot of fluidynamic, thermodynamic , and aerodynamic reasons why with a bunch of calculations to go through. But I guess I like to keep the more common sense approach. Maybe Tony the Tiger wants to give the reasons why, as he's done close to it.. But I doubt it.

Not trying to shatter the man's dreams, just get him down to earth a little, so he can at least still achieve some realistic results, that's all.

But, whatever, I'm kinda done here.

OneBadTurboCRV

Fully understandable, but WE know it is not possible, and since I don't have a reputation to tarnish, I really don't care WHAT he wants. It has been proven post after post he has no clue what he is talking about and has been reading too many domestic forums. I still disagree that 12:1 is considered extrenely high being that people turbo stock JDM ITR engines and they are about 11:1 compression. If that is the case then wouldn't 9:1 be extremely low rather than 8:1? I am not trying to rewrite terminology (as we all know you win in that regard "player") but in the realm of forced induction Hondas 12:1 isn't "extreme" for only a one number increase. Difference of opinion is all, no reason to be frustrated.