Boosting an FG FAQ

[Highrev1]

I gathered up some information and put together this FAQ about boosting an FG. Its just a start don't flame me If I have missed something Let me know I will add it.

Can my engine handle high boost?
The k20 series is a strong engine, but experts suggest not to go past about 9-10 psi on stock pistons as the ring lands can't handle prolonged stress.
However, it should be noted that all psi is not equal as 8psi on a small turbo will not equal 8 psi on a bigger turbo with more flow. So it's relative to flow, cylinder pressure and other data as well ... 2rotormotor-"experts suggest that 250wtq is the breaking point, but many have suceeded to do way more than that, and have done so without any problems... "

Just a quick note on engine wear and boost pressure. The key in all this is the combustion pressure and it's timing...which is why boost pressure isn't the end all for power or wear.
An engine makes power as a function of how much pressure you create in the cylinder and when that peak pressure occurs. Best power comes from peak cylinder pressure around 14 deg ATDC (after top dead center)....not to be confused with BTDC (before top dead center) which is when the spark occurs.... you see, if you spark at 30 deg BTDC and peak pressure is at 14 deg ATDC, then you know that it took 44 deg for the spark and subsequent combustion to create peak pressure in the cylinder. And 14 deg ATDC is a good number for most engines, but it depends on the pressure available under the curve to the piston (like a horsepower graph). If measurable pressure starts at 25 deg BTDC, then you actually get some of that combustion pressure acting the wrong way on the piston.
OK, peak pressure is based on a number of things including the amount of oxygen in the cylinder, the fuel (and how well it atomizes and disperses), and finally when the combustion process is begun with the spark. If you start it too early, then peak pressure can occur closer to TDC, and the combustion pressure has no where to expand to....whereas when it occurs at 14 deg ATDC, the combustion can push the cylinder away and your car goes forward.
Anyway, so it's easy to run 10 psi and retard timing to make internal cylinder pressure (combustion pressure) less than a 9 psi setup with more advanced timing. The key for good tuning is to balance the boost pressure with the spark timing in a way that doesn't create too much cylinder pressure.
There is one other component in all this.... and that is heat. Heat is not your friend. If you are getting too much heat buildup in the the cylinder, you can start to have increased detonation. That's why EGT parameters are important.
The key is to control EGT, knock, and optimize cylinder pressures with fuel tuning and spark timing. And btw.... a/f ratio affects how fast combustion happens... so changing fueling will change peak pressure timing as well... a little bit anyway.
So, there you have it.... the real answer to the question of "will a boosted Civic's engine wear faster", and the answer is yes beacuse of the increased pressure the rings must contain (or not be able to contain). But if your tuning is proper rather than sophomoric, then this can be controlled. Still, the whole point of forced induction is to create more cylinder pressure, and it will wear the engine faster that lower cylinder pressures. If I had to put a mileage on it, I'd say 5 psi won't affect longevity much. 8 psi may reduce it a bit, and 10 psi will be even more than 8. So, if you get 300k out of a N/A honda engine, then 5 psi might give you 280k. 8 psi might give you 240k. 10 psi might only give you 180k. It also depends how much you are in boost obviously.
The recommendation I give to people is that 10 psi is safe but will reduce engine life some. 8 psi is similar, but it's a safer option that offers power with longevity. And 5 psi will wear more or less the same as the stock engine.
But remember always that the tuning knowledge behind a forced induction product is key; so make sure the engine management is good and you'll be fine.
Chris

But isn't it dangerous to Boost an already high compression motor?
The FG's compression seems very high for any turbo- or supercharged car. However, experts here seem to feel that if you take care of the car and don't push it all the time, the engine should be able to handle up to about 10 pounds of boosts without breaking down soon... general k20 knowledge seems to indicate 250wtq as a breaking point for internals.



What's up with Fueling issues on this car???
Nearly all current cars use an in-tank fuel pressure regulator and so have only a single fuel line going forward to the fuel injector rail. Yep, that’s right – there’s no return line. So what happens when you want to make some modifications to one of these systems – say, to increase fuel pressure? The intank regulator needs to be modified. Now that intank regulator and the returnless system can only handle so much horspower before it needs to be modified.

Once you have reached that magic number you will need to add a return line. What this means is fuel is pumped from the tank to the injectors on through a pressure regulator with any excess going back to the tank through a return fuel line. This keeps the fuel system at a constant pressure for proper fuel atomization. Return Fuel Systems are easy to manipulate fuel pressure with an adjustable fuel regulator controlled by a vacuum boost reference. Under a supercharged boost situation the Reg. will "pinch" the return line (increase fuel pressure) forcing more fuel out the injectors. There are a couple of DIY's for the return line, and it is not difficult at all. This is one thing that will ensure proper fuel delivery and allow for a safer high horspower engine.

There is also an outstanding issue related with low gas in this car. "especially on this car for all forced induction applications ... do not boost the car if u are low on fuel ... ur afr will not be good and u can have a big boom" This occurs even at idle which is interesting cause fuel starvation usually happens if the gas tank contains only a few gallons of gasoline and the vehicle is driven hard around a corner, the fuel may slosh away from the pickup and momentarily starve the fuel pump, whcih can cause premature pump failure, and/or fuel pressure drop. This will be looked into to find out the real cause of this fluctuation in A/F. Datalogging fuel pressure, injector pulsewidth and airflow to see what is causing the change, should be done shortly by a member on the site. Either way N/A or F/I don't let the gas in your car get toooo low. The fuel pump is in the gas tank and the fuel cools the pump. If gas gets low for long periods of time it can cause the pump to overheat and fail.

To add to this now that more information is out...when the stock regulator is bypassed in the manner that it is done commonly now. the stock fuel filter is also bypassed. An inline filter should be used if following the current instruction.
The starvation appears to be cuased due tot he fact that the stock Regulator is bypassed and no longer dumping its excess fuel back into the small canister where the fuel pump resides. Simply hooking up your return line to this area may provide a solution to the starvation issue.


What is out there in terms of tuning?
Greddy uses their E-manage system. Moss Motors/JRSC uses a Vishnu Exede. All others I know of use a HONDATA re-flash. Hondata has been in the business of tuning for many years and knows their $hit. Review of the Re-Flash
Other options that will be coming soon.
AEM
"AEM’s F/IC is a PC-programmable piggy-back controller that allows users to retard timing and add fuel to virtually any engine, even on variable cam timing engines (VTEC, iVTEC, VVTi, MiVEC, etc.). The F/IC is the perfect solution for eliminating outdated FMUs and “boost hiding” electronics and is ideal for newer cars with knock detection that have non-factory forced induction systems."
Greddy's
"The V-Manage allows tuning of variable valve timing in older Honda VTEC applications where timing adjustments are "on-off" scenarios initiated by a solenoid or the newer generation iVTEC, Toyota VVTi and VVTLi, Mitsubishi's MIVEC and Nissan's CVTC that control the valve timing using a freer, progressive-rate strategy. The V-Manage not only adjusts the crossover point or VTEC threshold but it can tune the amount of retard throughout the rev range. The unit uses e-Manage Ultimate software and interfaces easily with an e-Mange Ultimate computer to make seamless corresponding fuel adjustments. Also the unit has an auto-learn feature to determine the engine's baseline cam timing scheme and DIP switches that allow the user to quickly switch between stock timing and programmed timing."
Tatcrix
"Datalog from any ISO 9141 (Chrysler, European, and Asian) vehicles.
Reflash most popular late model Subaru and Mitsubishi cars (2001+), including WRX and Evo. The key is that your wideband air/fuel data is completely integrated with your factory ECU data.
This allows you to view fully-synchronous logs, and import all EcuFlash-defined 3D table data and formats directly from EcuFlash generated ROM files into LogWorks charting for easy computation and comparison. This is quite simply the most cost-effective Subaru and Mitsubishi tuning tool on the market, including the WRX & Evo. "

When should I upgrade my drivetrain?
This question is purley relative. There are alot of factors that will determine if you will need a new clutch. Driving style, if your N/A or F/I if you abuse your car and dump the clutch regularly, expect to get a new one sooner rather than later. What is soon some people have lasted well over 50xxx miles boosted others last only a few hundred. If you are not out there beating up your car you should be fine with the stock clutch for a while.
Your tires, stock tires should help the clutch last, they will spin rather than grip putting less strain on the clutch... Slicks or Drag Radials increase clutch strain. If you use Drag tires expect your clutch to wear faster.

Safe AFR ranges?
Street2tuned..."the AFR should be no higher than about 12.5:1 under boost. Just cruising it'll go back and forth obviously. When I'm under boost or at WOT, my wideband reads between 10 and 12.5."

Under full boost?partial throttle/partial boost? cruising ??
Street2tuned..."between 10-12.5"

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The content of this thread is intended as a service to the forum users only. Highrev1 disclaims all responsibility for any and all mistakes or inaccuracies in the information. Further, Highrev1 disclaims all liability for loss or damage, which may result form the use of information on this thread.

Nothern NJ Installs PM Me!!! Don't hesitate

[civsnake]

Good job and thanks for putting this together. None of it's really new information but it's nice to see it all in one place where it belongs. Great for anyone who doesn't check the tubes regularly.

[codys8thcivicsi]

good read..makes me not want to boost though

[Cookstar]

The original post of this thread looks informative and unbiased to me.

[bioevolve]

Great info!

[SiPusher]

great post, very informative and a nice centralized source of info for us F/I noobs. the information must flow!

another question it would be cool to see addressed is the rest of our powertrain... at what amount of power would it be recommended we do other upgrades to keep us from killin our tranny / clutch or whatever else?

/requeststicky

[lit420_si]

great info. nice to know

[sickyute]

well... +1 ... i just had to scrap the one i was doing because u have the same stuff up there already ... just added a tid bit to ur post.

i'll stick this so it doesn't get lost.

if anyone has anything else to add to the first post ... PM the info to the OP so that he can edit/add ur info so the thread doesn't get cluttered and info doesn't get lost ...

[Omes]

Good stuff with starting up a boosting FAQ. +rep

[blueroadster]

Thanks for this thread. It is a great start and I would suggest (since there is not a wiki on this site) to have additions to the original post identify the contributor.

[Highrev1]

What do I have to do? Whats a wiki?

Oh any info added put in quotes and give the name to for credit? right?

[sickyute]

Originally Posted by blueroadster

Thanks for this thread. It is a great start and I would suggest (since there is not a wiki on this site) to have additions to the original post identify the contributor.

good point ...
the OP may do just that ... PM him or PM me or any other mod ... mods will edit it and give credit.

i just put my tid bit in blue so he knew i did it ... lol ...

[blueroadster]

Originally Posted by Highrev1

What do I have to do? Whats a wiki?

Oh any info added put in quotes and give the name to for credit? right?

A wiki is a site where registered users can add new content to a site and also contribute information to something that has already been posted. Here is an example from the Wikipedia site on that provides information on a wastegate.

[SiPusher]

good work on the updates, keep 'em coming. loving this thread. +1!

[PhYsIcS]

I've never really heard of 12.5 being safe for Forced Induction applications, when I supercharged my S-10 I was told to make sure it's never above 12.0 or you risk running too lean. With your high compression motors I have to say I don't recommend you have your car adjusted to above 12.0 either. In fact most turbo/supercharger applications have a A/F ratio around 11.6-11.8. It's not perfectly ideal, but it's not really rich either. So if you can adjust your car to around that, I would consider that a safe tune.

[2RotorMotor]

It seems that you are steering people away saying that the k20 can only handle 10 psi... This is simply not true, its been proven over and over again...
There are alot of people running more than 250wtq on the k20 on stock internals. Infact we even have someone local running 585 whp on a stock k20 block with cams, and he has been at it for a while.. That motor has been through n/a, s/c and finally turbo...

[sickyute]

Originally Posted by 2RotorMotor

It seems that you are steering people away saying that the k20 can only handle 10 psi... This is simply not true, its been proven over and over again...
There are alot of people running more than 250wtq on the k20 on stock internals. Infact we even have someone local running 585 whp on a stock k20 block with cams, and he has been at it for a while.. That motor has been through n/a, s/c and finally turbo...

250 wtq is a breaking point ...
there will always be the guy who makes 700 on a stock block and 400 wtq etc ... but how long does that last?
on another note ... every major tuner.organisation who's done a vast majority of setups will tell you that the "breaking point" for the k20 is about 250 wtq ... u simply go above that at ur own risk.
it could probably handle more ... but that's a point at which failure "may" start.

[2RotorMotor]

Originally Posted by sickyute

250 wtq is a breaking point ...
there will always be the guy who makes 700 on a stock block and 400 wtq etc ... but how long does that last?
on another note ... every major tuner.organisation who's done a vast majority of setups will tell you that the "breaking point" for the k20 is about 250 wtq ... u simply go above that at ur own risk.
it could probably handle more ... but that's a point at which failure "may" start.

thats a saying amongst people but its more like a myth, but thats long gone now. In the begining k20's used to blow left and right when supercharged or turbo charged in the begining. Same thing happend with 2j's back in the day.. people were blowing them with very little output.... when people got used to the motor thats when you started seeing 6,7,8 and 900whp on the stock block. Im sure you have seen people push this motor to the limit and then some and pull through.. 400whp on a k20 is cake...

[BATANG CITY JAIL]

subscribe!....


i heard that, underboost and your A/F R is below 11.5, you are just wasting your gas....

[sickyute]

i'll reference Sean(sp.) Church or church automotive and vtec.net member as a souce of my info, as well as Doug (last name unknown) of hondata...

others have said the same ... i'll stick to those 2...

i'll take their knowledge over any other