A Beginners Guide To Forced-Induction.

TokyoSkies

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So in the past few days, I must have posted 4 or 5 times in regards to this very subject. In lieu of that, I decided it'd be a good time to post a beginners guide to boosting a Honda (or any 4 cylinder engine, for that matter). I'm by no means an expert, or a professional mechanic, so this guide should serve as a simple reference. I'm not liable or responsible for any damage you may cause to your engine or car!

With that outta the way:

The questions I get asked the most are:
"HEY GUISE, I HAVE (so and so) MOTOR, HOW MUCH BOOST CAN IT HANDLE!? :D :D"

and

"Can I boost my car on a budget? I'm talking like $600!"

We'll start off with the first question. A lot of people are starting to boost (or attempt to boost) Hondas now. I see more and more people slapping SS Autochrome (now defunct, under another name) turbo kits on their D16y8's and cranking the boost to 18psi. This is a BAD idea. Boosting a car properly requires a lot of research, planning, and most importantly MONEY. This is not a cheap hobby at all, but it can be very rewarding if done right!
To properly explain what engine can handle what etc., you first have to understand what a turbo does. Rather than writing it up, I'll link to an external site explaining the basics of a turbo:
http://auto.howstuffworks.com/turbo.htm

Now that you've got that under your belt, and you understand how a turbo works, this will begin to make more sense. In the case of what motor responds best to boost, it's subjective. You can honestly make any motor respond well to boost if you have deep enough pockets. As far as motors that are naturally better for boost, there are quite a few in the Honda world. A general rule of thumb, is that Vtec motors have a higher compression ratio than that of non-Vtec. Higher compression is just that: high engine compression from the combustion of the pistons, causing more stress naturally on the walls and internals of the engine. Couple this with trying to boost, and if you're following me, you'll understand that this will eventually end in eminent and catastrophic failure (detonation. BOOM). This is not always true, but for the most part, it's general knowledge.

Now let's start with some of the more popular Honda engines:

B16
The B16 is arguably the most popular B-Series Honda engine on the market, and it's in a lot of vehicles both USDM, and JDM/UKDM through the factory, making it readily available for swaps. There are various models of the B16 (A1, A2, B etc.), but we'll focus on the JDM B16A (second generation), since it's the most popular to import and swap.
The B16 has a compression ratio of 10:4:1, which is relatively decent for a high-revving Vtec motor, but it's still a bit too high to boost. In order to achieve optimal results from this motor, the compression would need to be reduced with aftermarket Pistons, rings and rods, and you'd also want to sleeve the block to prevent it from cracking under stress.

B18B
Found in LS and GS Integras, the B18B is also a very popular swap due to the sheer availability of the motor. They are plentiful, and produce a decent amount of power. The compression ratio on the motor is 9:2:1 which is good for boost, and still manages to produce a decent 142hp and 127lb/ft of torque. A lot of people boost the LS, and they can be very reliable if under 10lbs of boost (my own LS had a stock bottom end with ARP headstuds and a Cometic headgasket. After a valve job, full tune up, proper tune, and a better exhaust manifold, I made 310whp on 11lbs of boost, and on 91 octane pump gas. It CAN be done).

B18C1 (GSR) and B18C5 (Type-R)
The B18c1 and c5 are not very popular for boost, and due to limited availability and ridiculous price of the motors, they aren't very common for swaps. People DO boost these motors, but the high compression ratios of 10:6:1 and 11:1:1 (respectively) make them unrealistic for boosted applications. There's a lot of work needed to reduce the compression and beef up the walls (aside from the B18C5).

B20B and B20Z
Found in the Honda CR-V's, the B20 is also a very common candidate for boost, although the thin sidewalls in the motor (as well as the LS) are a bit skeptical. If properly built (rods, pins, sleeves/block guard/girdle), the engine can perform very well under boost. A popular build is B20-Vtec turbo, but requires some pretty deep pockets to do it right.

There are several other motors (including the K series), but these are just a few of the common engines easily found. Now as for as what is necessary for boosting:

There are several kits available from several manufacturers to boost your car, including GReddy, Full Race, Peakboost, and more. These kits will set you back a good $2-3k, but are very well worth it. They provide every part necessary to bolt onto your car and go, sometimes including a piggy-back FMU (fuel management unit). A piggy-back is a separate device that simply sits on top of, and plugs into, your current ECU. It then allows you to modify your fuel map and ECU to perform better under boost.

If your budget is a bit tighter, you can piece together a kit. Be prepared to spend about $1500 on this, though, and it will require extensive research and knowledge. If done properly, your pieced together kit can last a really long time and be extremely reliable.

(cont.)
 

TokyoSkies

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(cont.)

Turbo Components
These are the basics to turbo components. There are obviously more to some kits, but these are what are absolutely necessary to get you up and off the ground.

Turbo
A lot of people start off with either the turbo, or the manifold. When boosting a Honda, there are a few different solutions. You could use a t25-t30 turbo from a Saab, Volvo, or Talon/Mitsubishi Eclipse. Lots of people use these due to their manufacturer reliability, and ease of rebuilding. Kits are literally all over the internet to rebuild these, and they are generally cheap and easy to find.
The other option you have is buying a turbo from a company like GReddy, AirResearch, Turbonetics, or Garrett. The most popular of these is the T3/T4 turbo. Their compact and fast spinning design is ideal for a 4 cylinder engine, allowing for very minimal turbo lag and fast spool/throttle response times. You may see a lot of dudes with HUGE ass t35 turbos on their 4 cylinders and think, "DAMN I WANT THAT BIG ASS SNAILLLLLL OH F*CKKKKK", but trust me, you don't. Our engines were not designed to compensate for boost as it is, and throwing a HUGE turbo on an engine built for n/a is a challenge, and generally kind of retarded (unless the engine is massively built or something).

Wastegate
The wastegate is designed to ensure and regulate consistent boost pressure. If your turbo is internally gated, this is done for you. If you chose to opt for an aftermarket turbo, it's likely going to require an external wastegate. There are a million different options, but first and foremost, DO NOT GO WITH KNOCKOFF s***. There are gates all over eBay claiming they are just as good as gates from companies like TiAL, Turbonetics etc., but they aren't. I've heard horror stories of springs failing and people having boost creep from 5lbs all the way to 22lbs (which will end in a big boom), and full on springs slammed shut, causing eventual catastrophic turbine failure (turbo goes, blades spin apart, get shot in your motor, and now your entire engine is gone johnson). Avoid this by getting a quality gate, and assuring that your spring rate is set at the amount of boost your setup is designed for.

Manifold
This is so over-looked it's not even funny. This is the MAIN part of your turbo build, and people still manage to skimp out/f*** this one up. The manifold replaces your header, and connects your turbo and wastegate to your block. There are several styles of turbo manifolds out, and they depend on lots of things. If you want to preserve a/c and power steering, they have manifolds that will do that. There are some that place your turbo on top of the manifold (top mount), and some that place it closer to the bottom of the block (ramhorn style). An essential rule of thumb, is to pay attention to the materials the manifold is made out of/made with. In log-style manifolds, cast iron is a common material, and a very good one. Craftsmanship and notoriety are very important in deciding on a manifold. Check user reviews/ratings, any complaints, and do research on your manifold.

Downpipe
The downpipe will connect the manifold to your exhaust. These are usually specially fabricated, but there are several options available online and in some performance shops. A key element is a flex pipe. Lots of people look past the flex pipe. What this does, is gives the downpipe a small section of metal mesh piping that is very flexible, and allows it to move and bend with daily driving. Once you get your car tuned and everything bolted on, your engine will likely shift (even if just a bit) under the torque of your build. When this happens, you want to make sure nothing breaks. Hence the flex pipe.

Exhaust
Pretty easy and obvious, your exhaust is also an essential part of any good build. The idea here is to exit gasses as quickly and efficiently as possible. A 3" setup is usually ideal for boosted applications.

Charge Piping
Charge piping connects your intake manifold, front mount intercooler, and turbine together. Charge piping is completely dependent on the vehicle you have, and the motor in that vehicle. If at all possible, get them custom fabricated, and eliminate as many pieces as possible (make as many single-piece pipes as you can). The less connectors used, the better the flow, the more responsive your throttle will be. You have the option of using anything from 2"-3" charge piping. The size is relatively dependent on your horsepower goal, but I would recommend sticking to 2.25" charge piping, and 3" exhaust.

Blow-off Valve
Yeah, you know what this is. This is what makes those cool, ricey noises. The real reason people use them, is to give pressure in your charge piping an exit point. If you don't have a means of relieving built up pressure, you will get compressor surge (also called turbo chatter, or what ricers refer to as "that sweet ass CH-CH-CH-CHHHH" sound. Contrary to popular belief, this sound is BAD and should be avoided at all costs! People will argue this, but it IS bad). This is caused when there is little/no exit for pressure in your charge piping, causing the air to be slammed back into the turbo housing, which then spins the blades in the opposite direction. After enough time, this will cause catastrophic failure (see the Wastegate post). There are lots of different styles available, including the knock-offs on eBay. Again, don't go with knockoffs. You will get screwed.

Intercooler
Intercoolers convert hot/warm air into useable cool air via a separation process (thanks to 2slo4u for clearing this up!) . The most common types are front mount (the bumper ones), but top mounts are used when people wanna go sleeper status. Surprisingly, eBay intercoolers are pretty decent, and are way cheap (like $60!). Just don't get something like a 5 core, massive ass intercooler (it won't fit inside your bumper anyway), or you WILL destroy your turbo.

Oil Lines
Your turbo needs a source of lubrication, and that's where oil comes in. Oil serves as both a lubricant, and a temperature catalyst. There are several options to go with, but the most reliable and best/easiest to deal with are steel braided lines with A/N fittings. A lot of people will argue against A/N fittings, but I prefer them. As long as they aren't shitty, they're reliable and easy. You can slap the fittings onto the turbo, your tapped oil pain (we'll get into that next), and then connect your lines. Voila, done. Well kinda haha. These can be ordered online in universal kits, or you can piece it together at most auto parts stores.

Oil Pan
As we explained before, you need to feed your hungry ass turbo some oil. There are aftermarket turbo oil pans for civics/integras that are a bit deeper (they hold 5 quarts. Good stuff) available, and they come pre-tapped, most with an a/n fitting on the oil pan. If you wanna get all Bob Villa on it, you can get an oil pan for your car from a junk yard and tap it yourself. Buy the fitting, find a good centralized location near the rear-middle of the oil pan (a position that won't hit the ground if you decide to slam your s***!), use a drill and drill out the pilot hole for the fitting, insert fitting, and seal it (most people use silicone). Then, just run the lines to and from. In this case, you have to make sure you've tapped the line where gravity will allow for proper oil flow. I'd recommend finding a pre-tapped pan. It's a lot easier.

Fuel Pump
Your turbo charged engine is going to burn through more fuel, so you'll need a pump that can keep up with the demand of said fuel. The best, in my opinion, is Walbro. The 255LPH is a great pump, and perfect for this setup. Installation can be a bit tricky, though, so make sure you have someone around whose familiar with it, or if you have the money, have it professionally installed.

Injectors
Injectors are important to deliver the right amount of fuel into your cylinders. There are lots of different options here as well. Size/type are dependent on your build. For a daily, I ran 550cc injectors (RC injectors, although I don't like the spray pattern..). Do a bit of research here, though, as you can use stock DSM injectors, but they will require a resistor box to be wired to them.

Vacuum Lines
Vacuum lines are pretty self explanatory, but are needed in order for your entire system to function. You will have more vacuum lines connecting your turbo, charge piping etc. Blox makes a wonderful product called a vacuum block that will eliminate engine bay clutter, and help you to route your vacuum lines directly from the brake booster (optimum and safest vacuum source, in my opinion). It's available in a bunch of colors/finishes. Check it out.

Wideband/5 Wire 02 Sensor
People avoid/ignore this part, but it's integral to any good build. A wideband 02 is necessary to properly map and tune your ECU, if you choose to opt out of the insanely pricey piggy back FMU/Standalone FMU's out there. They are readily available for all makes of cars online. Don't be cheap! Buy one!

Tunable ECU
You have a bunch of options here. I would personally recommend going with a Hondata system for tuning. Lots of professional shops love and prefer Hondata (and for good reason. Don't believe me? Check out Erick's Racing's 10 Second N/A civic, tuned on Hondata. Now imagine boost. Mindf***.). Hondata is a bit pricey, so if you want to cut the price down a bit, you can always opt for a pre-chipped ECU from companies like phearable.net. Their products are known for being good, but it always sketched me out a bit, personally.. There is also the Neptune/Chrome method for those of you who want to learn to tune your own ECU, but this is dangerous. Do so at your own risk!

There is quite a bit more to a proper turbo build, but those are the absolute basic components and features of turbo charging your car! Now that you have a bit of knowledge in your head, do more research, and plan your build meticulously! Take your time, save up money, and do things RIGHT. The single most important thing I can tell you, is to be SURE to have your car professionally tuned, IMMEDIATELY AFTER INSTALLING YOUR PARTS. Do NOT cruise around for 2 months without a tune. You're asking to blow your s*** up. Also, try to set a reasonable horsepower goal. 400hp on a daily driven single cam is not reasonable, at all. I don't care what other people say. It's not. I was shocked to get 310, in all honesty. 275 is a friggin lot for a stock Honda block. Remember that.

Some basic maintenance tips:
ALWAYS use full synthetic oil. If you've not used it before, be sure to flush your motor before using it. It just makes it a bit better on your engine components (just my opinion). Your car is going to go through more oil now, so I'd recommend an oil change every 1700-2k miles. Monitor your oil every other day by checking your dipstick. Make sure it doesn't get milky, or too dark, and of course, make sure it's not too low.
Never put anything less than 91 octane in your car. Your car is going to run hotter, and is going to make use of every square inch of space in the engine to dissipate fuel. The chemical compounds in lower grade fuel will cause lots of problems here, and can and will cause detonation if run for long periods of time. If you can afford it, and have access to it, use 93+ octane. You'll get killer results. Don't run alcohol or methanol. Your car isn't built for it.
Replacing all of your gaskets with upgraded, copper (cometic) gaskets is always a good idea. Particularly your head gasket. The pressure on your block/head will be pretty immense. Having a cometic head gasket will help to reduce strain/stress a lot.
Get a boost and oil pressure gauge. They will help you understand what's going on with your car under load a lot easier. A fuel pressure gauge is also a really good idea.
A turbo timer is a nice add-on. This will keep your car idling long enough to allow the turbo to cool down (if you just shut down your car when the turbo is still hot as balls, it will start to build up oil on the main shaft, known as coking. NO BUENO).

If any of you guys have any questions, feel free to PM me. As I said, I'm no mechanic. This is simply my hobby, and I have learned a lot through my experiences (building my teg from the ground up, aiding in building a 550hp STi, building a turbo D15 Del Sol on 22psi. Yes, 22psi.)

There's a general rule when building any car:
Fast, Cheap, Good. Pick two.
You will soon learn that this is absolutely correct.

I hope this info will help out at least a few people in their boost journey! Have fun, and be safe!
 


Last edited:

2slo4u

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Good info but some parts are not really correct. Intercooler doesn't suck in cold air. Hot air is passed through the intercooler and cooled when separated. And in my opinion the turbo would be the main part of the turbo kit because you build the parts and tune accordingly to the turbo
 


earlybill1

New Member
So can you tell me the compression of my d16y8 and all the no no's on turbo build for it and any advice my pockets are not deep just don't have any idea where to start from junkyard to new I've seen junkyard turbo civic last years on stock motors in Knoxville tn

Droidx,97CIVIC
 

TokyoSkies

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Good info but some parts are not really correct. Intercooler doesn't suck in cold air. Hot air is passed through the intercooler and cooled when separated. And in my opinion the turbo would be the main part of the turbo kit because you build the parts and tune accordingly to the turbo
I guess I kinda goofed on the intercooler part lol. I knew that :P I'll edit the post to fix it.

I agree that the turbo is ALWAYS the focal point of any good build, in my opinion, but some people build their whole kit around their manifold (to save space/preserve ac and what not). I guess for a DD/basic kit, that's alright.
 

TokyoSkies

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5+ Year Member
So can you tell me the compression of my d16y8 and all the no no's on turbo build for it and any advice my pockets are not deep just don't have any idea where to start from junkyard to new I've seen junkyard turbo civic last years on stock motors in Knoxville tn

Droidx,97CIVIC
D16y8 compression ratio is 9:6:1, not too bad. I've heard a lot of people boost these, but I've never really messed with a single cam. They aren't particular popular build motors due to the minimal amount of horsepower/torque they produce. As with any engine, if you're going to boost it, do it right. Tear it down, rebuild it (rods, bearings, pistons, sleeved, ARP headstuds, valve springs/retainers, valve job etc.) and do it right. Take your time. Too many people rush into boosting just cause they want to be fast, quickly. Don't do that. You'll regret it.
 

BioHazard the Reaper

PHACM 1B
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another part that seems off -- oils primary reason or reason at all really(as it seems is stated in this) is not to cool your turbo...its to lubricate...in fact without an oil cooler, it really just makes it hotter, but since its purpose isn't for that, it doesn't matter.


Also, wastegate and blow off valve you have somewhat opposite -- the BOV keeps the turbo from getting huge back pressure you go to shift, and all of a sudden this charged air has no where to go (the throttle plate is closed, trapping it), so when this happens, instead of the pressures only way out, being through the compressor housing, the BOV is forced open allowing the pressure out. It doesnt, deal with exhuast gas at all, only intake, and it doesnt provide constant even pressure, it only opens when sudden pressure rises from closing the TB (which i guess you could argue would be keeping it "even"). if it kept it constant and even (and itd have to by opening during acceleration) youd have a lot of angry people not being able to tune cars cause the bov would allow for huge boost flucuations.

as for the wastegate, is mostly right, its designed to dictate the amount of boost you will be running, it doesnt really keep exhuast gas from "going back on the turbo", it helps keep boost the same by opening or closing, to allow exhaust gas to bypass the exhuast turbine, thus not spinning it has hard, in turn, not compressing as much air.
 

mymmeryloss

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Very well put!


Sent from my Butthole using Fart power!
 

TokyoSkies

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another part that seems off -- oils primary reason or reason at all really(as it seems is stated in this) is not to cool your turbo...its to lubricate...in fact without an oil cooler, it really just makes it hotter, but since its purpose isn't for that, it doesn't matter.


Also, wastegate and blow off valve you have somewhat opposite -- the BOV keeps the turbo from getting huge back pressure you go to shift, and all of a sudden this charged air has no where to go (the throttle plate is closed, trapping it), so when this happens, instead of the pressures only way out, being through the compressor housing, the BOV is forced open allowing the pressure out. It doesnt, deal with exhuast gas at all, only intake, and it doesnt provide constant even pressure, it only opens when sudden pressure rises from closing the TB (which i guess you could argue would be keeping it "even"). if it kept it constant and even (and itd have to by opening during acceleration) youd have a lot of angry people not being able to tune cars cause the bov would allow for huge boost flucuations.

as for the wastegate, is mostly right, its designed to dictate the amount of boost you will be running, it doesnt really keep exhuast gas from "going back on the turbo", it helps keep boost the same by opening or closing, to allow exhaust gas to bypass the exhuast turbine, thus not spinning it has hard, in turn, not compressing as much air.
Right. Those were the points I was trying to convey :P maybe I worded it incorrectly. I'll go back through my original post and reiterate so that it's clear. Thanks!

Very well put!


Sent from my Butthole using Fart power!
Some great info here, helped out a lot
some good info in here :thumbup:
Thanks guys!
 

TokyoSkies

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b18c1 is hands down the best b series motor to boost

stock they handle 350 all day
Eh. No, not really. They blow regularly. They're high compression motors. Yes, they have a nice output, but it doesn't last long when all that strain is put on the block.
 

French-Frye

New Member
In reguards to the vacuum lines. Is there a schematic for running them? cause my b16a turbo isn't building boost and I think I have vacuum lines mixed up. Any help?
 

mylovehx

Hatches rock
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could you school me in the 3 wire to 2 wire IACV? i know all the wiring business. Do i need a 2wire iacv? love you
 

got traction

i rock the sohc
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In reguards to the vacuum lines. Is there a schematic for running them? cause my b16a turbo isn't building boost and I think I have vacuum lines mixed up. Any help?
post picture of vacuum line routing. Are you not seeing boost on a guage or in the software?
 


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