I have read a lot of conflicting information concerning the strength and engine management issues when boosting Honda’s D series engines. So, with that said I hope we can dispell some of what I've seen.


Boost Pressure on a stock bottom end - I’ve seen numbers ranging from 5psi up to 12psi. I’ve noticed on the kits that different manufacturer’s sell start at 6 to 7psi, but the owner’s of these kits seem to turn up the boost. I’d like to be near the limit of the motor (50k easy miles), but still have a good margin of safety. I’ll definitely be running an intercooler, which should also help.

Engine Management (read: fuel delivery) – What is the best setup to deal with the boost and keep the cost down? I’d love for Santa to leave an AEM ECM, RC injectors, and a new fuel pump under my tree, but lets face it, I haven’t been that good this year.:naughty: So, what other options do I have, and what are the benefits/drawbacks of each? I want to do it right without spending large sums of money.

Thanks,
Andrew

 

I'm running 8-10lbs of boost daily on completely stock internals. The only significant problem I've had in over 2 years is a leaky headgasket, and that didn't happen until a couple months ago, and was easily dealt with. I would say if you can run up to 8lbs of boost with an excellent safety margin, and a bit more if you're confident in your tuning. Some people run 12lbs of boost daily on stock D series blocks, but stock rods are like toothpicks, so I would say that would be the max I would run on a daily driven stock D block, and only if your tuning is up to snuff.

The cheapest way to get enough fuel for 8lbs of boost is to use a 12:1 FMU and an inline pump. You can get them for less than $300, total, and they'll allow you to run 8, maybe 10lbs of boost on stock injectors. The reason I cap the boost level at 10lbs with a 12:1FMU setup is because of the extremely high fuel pressures that they produce under boost. Even at 8lbs of boost, if your static FP is 40psi, your FP under boost is going to be 136psi, which is already pretty high. If you raise the boost level beyond 8lbs, your FP is going to go up 12psi per lb of boost, and it doesn't take long for FP to go extremely high.

A much better, although slightly more costly fuel setup would be an AFC and some 450cc DSM injectors. An AFC is around $300,a nd DSM 450s can be had for ~$50. With the AFC set at 40% fuel trim, you'll be able to run and idle the 450s with no problem, and the decrease in the MAP signal also allows you to run up to 10lbs of boost without the need of any check valves, and you won't throw a MAP code. You'll need to wire in a resistor pack, or inline resistors into the injector harness, but that's not very complicated. With this setup, you won't have skyhigh FP's under boost, either, and you have room to upgrade down the line. If you decide to step up to that AEM you have your eyes on, the 450s will work with the EMS, and you can sell off your AFC.

 

Thanks for the response, I appreciate your input.

And still use the stock fuel pump, or do I need to upgrade/get an inline fuel pump?

If I manage to nail down the tuning do you think that I can manage to maintain Honda reliability running a boost controller at 6psi 90% of the time and 10psi the other 10%?

 

With the 450s and the AFC, your stock intank should be fine. You can upgrade to a Walbro intank later on if you want to have a little extra security. 6lbs of boost daily, and 10 on occasion should be no problem. As I said, the most common thing is a leaky headgasket, and that's not really that big of an issue.

 

When i was deciding on a turbo the thing that turned me away was how to get fuel. Then as i started reading threads i learned that fuel wasnt that big of a problem. In your case the fmu way will be fine.

For fuel:
FMU + inline fuel pump = okay
afc + bigger injectors (450cc dsm) = better
standalone + bigger injectors = best

 

I've noticed a lot of people using DSM Injectors for their Hondas, I guess it's because DSM is better

 

If by better, you mean cheaper
DSM 450s - ~$50
RC 440s - ~$270

 

sup P, i have a 2000 civic ex with d16y8 stock engine @ 20K mileage. so, if possible can you list what i would need to start a turbo setup running at 6-8psi daily driven?

there is a guy at RAZO in milpitas that wants to sell me his 92-95 greddy turbo with a R31 intercooler. but i've heard i need to modifiy my piping. so i don't know what else i would need. as for DSM injectors, i think i can get those from prostreetonline.com, i know the owner, John Huh. we go to church together. also, how would i go about tuning the turbo? could u tune it for me if i roll by, i mean if u won't mind... i'll buy you lunch or dinner...

btw, do you know how much whp u got with ur setup? cuz i need all the help i can get... lol... clueless when it comes to turbo... just know how to install it... i think...

 

The GReddy kit is a good street setup, but I'm not too sure about RAZO. The only time I ever went in there I got quoted some rediculously high prices and I also think they do their installs either in the parking lot or in the back alley. If you get a GReddy kit, the simplest way to get it ready to run 6-8lbs of boost daily is to ditch the GReddy box that's supposed to trick the ECM into not seeing boost, and replace it with either (fish tank)check valves, or a Missing Link aluminum check valve. The GReddy kit also comes with a 12:1 FMU, but no inline pump which means you'll need to add an inline pump if you want to turn up the boost, or else you'll lean out.

Just the addition of an inline pump and check valves will make you pretty much ready for 6-8lbs of boost, but you'll be running pretty rich with the FMU setup, so in order to tune it, you'd need some way to trim fuel under boost. Something like an AFC or SFC would be good.

Of course, if you're planning on running the DSM's, you would ditch the FMU entirely, and you wouldn't need check valves either. You would just need an AFC, and maybe a Walbro intank pump if you want(not totally necessary). In order to wire up the DSMs, you would need a resistor box out of an older Accord or a CRX(any Honda with peak-and-hold injectors), as well as the injector clips to match your DSMs. If you can't find, or don't want to buy a resistor box, you can wire 7-8 ohm resistors into the injectors harnesses. As for places to get DSM 450s, dsmtrader.com is a prime resource. For the resistor box, you can usually find them on eBay, or The Parts Trader.

As for tuning, it's hard to tune perfectly without getting it on a dyno. If you plan on running the AFC with the 450s, your base settings are going to be -40% across the board, which runs and idles fine, but you'll need to fine tune it on a dyno with a wideband O2 sensor to get the best power.

 

The easiest way to go turbo will be to get the greddy kit. The cheapest way will to go custom. I bought a custom turbo kit. That was a total waste. Now that i think about it i could have easily made the kit myself for a cheaper price. But oh well at least im boosted.