So I know I'll probably get flamed for posting a thread like this however bear with me there is so much misinformation and inconsistency in the current threads I already read through that I think my only option to get a good answer is to post a new one. I just dropped off my B18C1 block at the machine shop today to get hot tanked and have the crank polished and the cylinders honed. To create a base to go off of this is my build:

GSR 5spd transmission
solid motor mounts to minimalize wheel hop
Stock sleeve B18C1
JE forged pistons 10.0-1 I believe (came with the old B18B and I'm hoping to be able to use them to save cost)
Eagle H Beam rods
ARP rod bolts and head studs
Stock Head Gasket
No block guard because of poor coolant flow/overheating risk
Stock B18B head rebuilt ported and polished and port matched (non VTEC I feel is better for this application plus easier to tune on plus I don't have the money to pick up a GSR head and already had two B18B heads laying around)
Dual Valve Springs either BC or Skunk2 with titanium keepers/retainers
Stock B18B camshafts
GT3076R or Precision 5858 have yet to determine which turbo exactly I will use I need to determine what power goals I can relatively safely achieve with my setup (I know "safe" is highly subjective when building a stock block)
E85 fuel (I figure if I have to change injectors and such going turbo may as well go the extra mile and convert to E85 as well, plus there is more power to be made over 91 without having to add extra boost psi. To me that seems like the "safer" option as well because it is less detonation prone than 91)

I have been trying to find out what the rough limits would be power-wise running E85 and trying to keep boost psi at as low a level as possible so I don't destroy the bottom end too quickly (mainly the sleeves are my concern) this won't be a daily driven car however I would like to be able to drive it as often as I like without worrying. Will I be able to make my power goal of 300-350whp running E85 and keeping boost psi relatively low (8-12psi)? I know a large factor is the tuning which I do not plan on skimping on whatsoever. I will most likely be tuning on Hondata with a reputable tuner here in Colorado.

"Safe" is not a good word to use I know, but you guys know what I mean when I say I want this to be as safe of a setup as possible to make my power goal without having to sleeve the block. If I had a sleeved block I'd be shooting more for 500whp anyways. If I forgot to clear up any other important details let me know.

 

i run a gsr completely stock internals aside from headstuds and headgasket, and i have been making 309whp for over 20k miles, i drove from miami to daytona beach and back and had zero issues.
its all in the tune

second of all e85 is not necessary for your power goal, i make 309 224 tq at 10 psi on a sc61 with 93 octance.
with a decent sized turbo and 13-15 psi 350 is cake, make sure you have your cooling system down and you're golden.
if you want longevity while daily driving use the oem 02 sensor when you tune it that way it keeps your a/f from going out of whack due to weather or climate changes.

 

Thats good to know about the O2 sensor for sure. I know E85 is not necessary however I kind of may as well switch over because I have to upgrade fuel pump, injectors, get a tune, etc. E85 is roughly equivalent to 100 octane if I'm not mistaken so the detonation resistance is superb which is ideal. Also I am at 5k feet elevation which makes obtaining higher power goals harder. I'm assuming you're down closer to sea level. I know that there are certain stock components that *can* handle the power it's just a matter of me not wanting to push limits and build as safely as I can that way I don't blow it up by some fluke thing happening trying to push stock. The only things I'm running stock are the head besides the valve springs and the sleeves because they're iron.

 

I guess I'm trying to figure out.. Why a B18bcylinder head? And using NO 02 sensor (narrowband) is better then even one. Use a wideband for tuning only and be done with it.

See, you thought you were going to get a consensus of the same answers regarding your questions to get that nice "fuzzy feeling" about your build.. WRONG. Welcome to H-T

 

I'm using the B18B cylinder head because I don't want to drop $700 to get a VTEC head... I already have two freshly rebuilt B18B heads laying around so I figure I may as well use one of those. I'm using the B18C1 block because I got it for a steal and the previous owner managed to break an ARP rod bolt which put a decent sized hole in the B18B block and was threads away from throwing a rod. And wait are you saying using no O2 sensor is better than using the stock one? I was originally planning on getting a Bosch wideband. And I'm not looking for a fuzzy feeling haha I'm trying to make sure I build this thing right the first time so it doesn't have to come back out of the car or blow up lol. I was hoping to get a response from you! You offer great insight on other threads I've read

 

I appreciate it. I try, although i do tend to be a bit blunt on my responses, so please forgive me in advance.

I'm saying that a wideband is for tuning only. All it really does after that, is to scare the **** out of you. Having one on board is fine. But there's little you can do about it, other than shut the car down in an emergency. So, yes, if you want to use one when your tuner does not have one, then great, but don't be fooled by its potential unless you're doing the actual tuning.

As for the B18C1 head. It just may be from your area that you're paying that amount of money for. But the amount of torque and better powerband is much more worth having a stock VTEC head than a port/polished / super cleaned B18B. there's a HUGE difference in their abilities, and will change the way that the car will behave. Even how much boost pressure is needed to run in order to get to your goal.

There are TONS of people with B18B heads. Each time, they went to VTEC to get a better utility.

 

Are you using a gsr crank and rods in the gsr block? That's basically running a destroked non-vtec and not a good idea imo. If you are stuck on staying non-vtec at least use and ls crank & rods in that block. For only 350whp look for a smaller more responsive turbo. The turbo choices you listed are good for 500+whp and would not be a good match for a low reving low flowing b18b cylinder head. What are you using for your ems? imo it's a good idea to keep the stock o2 sensor and enable closed loop fueling after your tune is done. Having a wideband in the car to keep an eye on is a good idea too.

 

There should be a TheShodan appreciation thread for dealing with these types of build threads on a daily LOL.

Keep up the good work!!

 

I don't care about blunt I care about correct I'm trying to measure twice cut once here if you know what I mean. I want to be able to put this thing together and throw it in the car and not have to take it back out again. That's why I'm concerned if the power level is too much or not. Thanks you for the clarification on the O2 sensor that's good to know. That sucks about the B18B head... I figured if I port matched it and ported and polished it I could hopefully be on par with a VTEC head. Guess it's time to try to find a VTEC head... they're just stupid expensive because everybody out here wants them haha and the internet is no different. My main concern right now is power goal, I don't want to crack a sleeve or anything. That's another reason I wanted to run E85, higher octane rating as well as the cooling effect it provides. My understanding is that I could achieve more hp with the same amount of airflow running E85 vs 91 (we rarely see 93 out here it's more rare than E85). Which if this is true I want to run E85 because I could achieve more power on less boost pressure which to me seems like it would in turn be putting less stress on the sleeves. If I'm not mistaken it's pressure not necessarily power that is detrimental to the bottom end. So if to achieve *hypothetically speaking* requires 15 psi on 91 vs 10 psi on E85 with the same turbo then E85 is the "safer" option. Or am I wrong?

 

The LS and GSR are both 1.8L running rods and crank for a GSR isn't going to destroke anything? They're the exact same blocks from my understanding, just one engine is VTEC and the other isn't. You are correct on the turbo sizing I went and checked because it didn't seem right after thinking about it and I was thinking of turbos I was looking at for my H22A Prelude build. I'll probably go with something like a 16G to try to achieve that power or maybe if my budget allows I'll pick up a new GT2871R or something. I need to do some compressor map sizing to see exactly which one I want to buy. I'm not exactly sure on the EMS I want to run yet, Hondata is an obvious choice it's just expensive, and I know somebody who tuned Crome very well. So I'm up for arguments for either at this point haha.

 

No sir. There are some nuances that you need to be aware of between the two engines. Not to mention the custom work needed to put the B18B head on a GS-R block. But that's for people smarter than me to discern because I only use VTEC heads based upon the same reasoning we've mentioned earlier. So, now... onward to the nuances.

GSR- 1797cc
B18B - 1834cc

The difference is the rod length and crank stroke. Putting in a GS-R crank/rods using a B18B head will keep you under the 1797cc. You'd also be at about 9.4:1 compression using a 10.0-10.4:1 compression piston compared to a GS-R. This is going completely backwards. If anything, you want the B18B Crankshaft and rod length in the GS-R Block with plugged oil squirters to take advantage of the torque multiplyer gains you'd get from that, not go backwards by... in essence.. lowering the stroke of the engine. That means it will take even more rpm to get the power/torque you're looking for plus now you're running a low-cfm flowing head from a B18B. . Bad choice, Joyce...


Heh, yeah, no 16G would ever make that power without being easily over 25-30psi of boost pressure whether you're talking the 16G5 of the Evolution 8-9 or the "Big" 16G of the Evolution 3. It's not going to happen. It's hard for it to happen on great flowing VTEC heads much less an LS head, which requires camshafts (Crower 404s come to mind thanks to Lightningteg.... who also switch to a VTEC head, BTW) matching valvetrain and new valves, in addition to your port-polish head,.

GT2871R, may do the trick, but again, depends upon the cylinder head you're using. The more efficient the cylinder head design, the easier it is to utilize manifold pressure to get the power and torque you want from that similar sized turbocharger.

First you need to decide on the engine platform you're going to use. If you decide to use the LS head, match it with an LS block. If you have a GS-R Block, save yourself money / time/resources and get a VTEC head. Then you choose the turbocharger to match. because the same turbocharger on these combinations make tremendously different results.

And for goodness sake, get rid of CROME. At least come into the 21st century , a little. Again, saves time, money, and resources getting supported hardware to make this work.

 

So I've done a bit of refresher reading after work today.
Generally, in order to support 10 flywheel horsepower you require 1LB/MIN of airflow moving through an engine. Assuming 10% drivetrain power loss, in order to support 300WHP I need to be making around 340 crankshaft hp, which means I require 34LB/MIN of airflow. I need to find a turbocharger capable of flowing this much air at a decent RPM (3k-3.5k I would say is ideal for a street car) with a 70% or better efficiency so as to not generate too much heat. Heat kills, and also makes cooling the intake charge more difficult. At this point it is looking like I will have to pick up a VTEC head, which makes calculating engine volumetric efficiency a little easier having the full B18C. Most if not all VTEC motors' VE is at or above 100%, for example my H22A's VE is around 105%. And the F20C is at an astounding 112%. I have yet to find a concrete VE number for the B18C but I would safely guess it is somewhere between 100% and 105%. I'm going to assume 95% to be conservative as I live at a higher elevation and the air is not as dense (barometric pressure is closer to 12psi rather than sea level's 14.7psi) My required boost pressure to make 340chp is around 11psi I calculated this by finding desired Pressure Ratio (PR) with the following equations:

CFM is simply LB/MIN x 14.27

CFM = Engine size in Liters (1.8) x Max RPM (8400 stock B18C redline) x VE (95%) x PR (Y unknown) all divided by 5660

Solving with some basic algebra

485CFM = (1.8)(8400)(95%)(Y) / 5660

2,745,100/(1.8)(8400)(95) = (1.8)(8400)(95%)(Y)/(1.8)(8400)(95)

1.91 = Y (desired PR)
So my required Pressure Ratio is 1.91

To calculate how much actual boost pressure this equates to we do this equation:

PR = Atmospheric Pressure (@5000ft Altitude 12.23) + Boost Pressure (X) / Atmospheric Pressure (@5000ft Altitude 12.23)

1.91 = 12.23 + X / 12.23

23.36 = 12.23 + X

X = 11.13 psi

So in order to achieve 485CFM or 34LB/MIN which would support 340chp this engine at 95%VE requires roughly 11psi of boost pressure.

Taking that desired PR and plugging it into a few compressor maps (along with some other required engine calculations I won't go into) this is what I found:

Full 11psi of boost as early as 3500RPM on the 95%VE B18C for the GT2871R with peak power falling near the 70% turbo efficiency island (peak boost hits a tad later than I'd prefer however 70% efficiency is perfect. This turbo is fairly well suited to a 300whp power goal, but we can do better)

Full 11psi of boost as early as 3250RPM on the 95%VE B18C for the TD06H 20G with peak power falling in the 76% turbo efficiency island (incredibly good efficiency with peak boost coming online 250RPM earlier. Better suited for a 300whp goal than the GT2871R)

Full 11psi of boost as early as 3300RPM on the 95%VE B18C for the GT3071R with peak power efficiency falling in the ~72% turbine efficiency island (slightly better than the GT2871R however not as good as the 20G)

So at this point it's looking like I will be trying to run a TD06H 20G turbocharger, unless somebody knows of any other similarly sized turbos I should read the compressor maps for that may be even better suited. Although I'm not sure I'll be able to beat full boost at 3250RPM and peak power at ~76% turbine efficiency. Those are really good numbers.

AND if I were to do a light port and polish and port match on the VTEC head just to clean up casting marks and such I would see an even bigger increase in VE, as previously stated 95% is a fairly conservative assumption. Especially with a port/polish/port match I would be looking more at 100%-102% VE most likely, which means even more airflow at any given RPM for even faster spool. I'll play around with different sized housings as well to see if I could find an even better match for that 300whp goal.

I will be taking your advice Shodan and getting my hands on a VTEC head, and I will most likely be purchasing Hondata to tune the car as well. As you said "coming into the 21st century" haha. Reading into tuning specifics for this engine is so hit and miss and difficult to find it's frustrating. I can't find definitive answers on anything.

My question still stands however and has yet to be answered on how much I'm pushing the stock sleeves running 340chp on E85. From my reasoning it doesn't seem that bad but I don't want to find out if I'm right or wrong by cracking a sleeve in my freshly machined B18C block, I dropped it off at the shop yesterday. Getting bored .040 over, got tanked, having the GSR crank micropolished, and the machinist said the deck was all good so I didn't have to pay to deck the block thankfully.

I appreciate the insightful information about the differences between the B18B and B18C thank you! My JE pistons are 10.0-1 compression so running the VTEC head will I still stay somewhere around that static compression ratio?

What now? Am I overlooking anything?