Hello all,

Was wondering if you folk could tell me if I am on the right track.

I am preparing to turbocharge my stock internals d16z6, from what I understand from my research 220-250 hp is the maximum reliable power range to expect from my engines stock internals. Because of this, I am shooting for between 200-220 hp at absolute MAX. Currently I am NOT going for numbers, but only to learn and maybe improve over stock power output.

The turbo I am going to use is a t3/t4 .57 trim. (price was right). I am shooting for between 8 and 10 lbs of boost, based on my calculations.

To get a rough idea of the lbs/min my engine would be flowing at redline, I did the following formula:

RPM * Displacement (L) / 12964 * (boost psi + 14.6) = lbs/min, taken from post #5 of: https://honda-tech.com/forums/forced-induction-16/how-calculate-engines-air-flow-rate-208032/
7200*1.6/12964*(10+14.6) = 21.86 lbs/min

From what I have read, a general rule of thumb is 10hp/lb/min. So: 21.86lbs/min*10hp = ~218.6HP

At ten psi, I should have a compression ratio of (boostPressure+atmospheric/atmospheric)(10+14.7/14.7) = 1.68
This appears to put me nicely in the island of efficiency according to this map: http://i205.photobucket.com/albums/b...vo/T04E_sl.jpg

Obviously these formulas make gross generalizations and assume ideal conditions, so I can only assume I will make a fair bit less than this, especially with a conservative tune.

My question is, do these numbers seem to be on the right track to imply that I can run my t3/t4 .57 trim, running close to peak efficiency at 10 PSI and be well within the generally accepted power limits of my stock engine? If not, would anyone be willing to explain why, and walk me through figuring it properly?

Thank you so much for your time,
Matt

 

Generally on a bone stock D series your gonna be limited to around 200hp. It wont hold together at 250. The 57 trim will spool pretty well and make nice power. Dont worry about how much boost just worry about power output. A single i tuned made 207hp on 10 pounds with a 57 trim and held together for years.

 

If you're only shooting for 200-250 and don't plan on building the motor for more power then the 57 trim t04e is overkill. You would be better off with a straight t3 60trim. You would make the power you want and have a much broader, more useable powerband with lots of midrange torque compared to the t3/t04e

Not to mention how much quicker the turbo spools/responds

If the price was right on the turbo and isn't some eBay china piece of **** then sell it. Either here or on eBay or both. Then take that money and get a turbo that's much better for your goals

 

In fact, the turbo is a china POS. From my research, a china POS that is not pushed can and does last for a time (I have witnessed it as well). My next goal is to replace it with an identical, (or different size, such as a T3 60 trim you mentioned) that is authentic. But for now, as my main goal is to just learn about turbo systems and fuel management, I think it will suffice. I have alternative modes of transportation, and modest goals anyways. If the turbo munches after some amount of time, I am okay with it.

Down the road I would like to produce more power, I am starting to research piston and rod configurations for more power. Currently though, I just want to get going with something I can learn about tuning with. (As well as junk vs authentic turbos :D).

My main question currently is if my calculations make any sense? Am I making any large mistakes in my figures to determine if I am going to blow up my engine from producing to much power? Or worse, is my chain of logic to determine that I should be under the power limits of my engine incorrect?

I understand there is likely more optimal turbo sizes to go with, and experimenting with those can and will be another point of learning down the road. I also understand that I am taking a risk with a cheap turbo, and that it may well fail prematurely. I can account for that risk though, my motor on the other hand would pose a bigger issue.

Thank you for your input, I really do appreciate any knowledge I can get. Also, I don't mean to sound argumentative about any of this, I am just laying out my thoughts and design choices. At the end of the day, I do not have the funds to purchase a new brand name turbo currently and still be able to afford the rest of the parts for a setup (fuel management...ect), taking this risk allows me to learn more quicker. That is worth it for me.

 

Why do you people keep sticking up for the POS eBay turbo's? Just a bigger headache if you ask me.

 

I don't recall sticking up for them, in fact I blatantly said it may well fail on me. It's simply a design choice I made in accordance with my goals. I am trying to learn about fuel systems and turbo installs, I can do that with a lower-quality turbo. Sure, it is not ideal, but it is a reality on my budget.

If my goal was a long-term reliable setup, I would be forced to wait until I could afford a name-brand turbo. As it turns out, my long term goal is that, and as I said previously I plan on upgrading to a higher quality turbo in the future. Currently though my short term goal is only to gain the most first hand experience for my dollar, and my choice will help achieve that. Even if it is experiencing first hand how quickly a eBay turbo munches itself.

I understand people getting upset about people having unrealistic expectations from a cheap eBay kit, or otherwise cutting corners with a turbo build and then being upset when it doesn't meet their expectations, but I feel I am being fairly reasonable here.

Maybe I am wrong though, I would love to hear a discussion of why I am.

Thanks,
Matt

 

Stop saying that. It's an excuse impatient/lazy/cheap people use to justify not doing it right the first time. Don't know why you cannot "learn" with a legit component right off the bat.

You did a lot of solid research but your choice of hardware was not smart.

 

I am really having trouble understanding why my choice to buy a questionable turbocharger is relevant to the topic. I was asking if my method of calculating the upper level of power output was at all sensible, not whether or not it was advisable to buy a generic turbo.

I'm not coming here complaining that my choice in components blew up my motor and I don't know why, nor am I advocating that it is a better way to go about turbocharging a vehicle.

I have spent many hours reading reviews and experiences with the turbo I purchased, and similar ones. I picked the most reputable 'ebay turbo' I could afford, which happened to be a godspeed performance turbo. I understand the risk I am taking, and you won't find me complaining about it if it blows up on me. I found it to be an appropriate balance for my wants and goals.

Back to the topic at hand, does my methods of computing the upward bound for power output seem reasonable? If not, why? I am willing to risk a turbo going on me, but I am less willing to risk tearing my motor apart because I am producing more horsepower than the engine can handle.

Thank you all again for your time, I really am not trying to start a fight here. I understand that aspects of my build are questionable, but I really don't think that is the scope of this topic.

 

I think the choice of turbo will be a bit laggy for you, I get what your asking, but will the car be dyno tuned? I think the best way to get a answer for your question is to look threw dyno charts of similar setup's and see how much lbs it took them to get there.
Im a firm believer in dyno tuning, might be a option to look into.

 

Yeah, I imagine it will have more lag than optimal, but for my purposes I don't think it will be a big issue. We'll see though, if I am bothered by it I will keep that in mind when purchasing a quality turbo down the road. Another thought I had is with a larger turbo I would stay away from boost during normal highway cruising and driving, giving me better real world gas mileage. Is that at all true?

I intend to dyno tune it when the build is finalized with a quality turbo, and possibly a cam. Until then I was going to street tune it very conservatively. I need to research that option more though first.

The nearest dyno is 4-5 hours away, so I want to get it tuned with a dyno in a long term configuration. This also gives me an oppurtunity to experiment with street tuning if it turns out to be a valid option.

 

Nor do I understand that.. especially when they have every intention of getting a proper turbocharger later. It was always throwing good money after bad.. makes no sense.

But I don't want this to go off topic.

 

Well I can understand the anticipation and need to get a car running... and sometimes that means cutting corners(sadly) or leaving certain parts of a build on hold for a future date

But more times than not the corner cutting will come back to haunt you well before you've ever considered completing those parts of the build you delayed

And dyno tuning is almost mandatory... it's the only way to safely tune all aspects of the car... street tuning comes after to refine things like low load/cruise speed driveability, part throttle tuning etc. Situations that cannot be accurately recreated on the dyno. Plus on the street moet tuning is done in 2nd gear, ae you likely don't have enough straight and level road to do a complete 4th gear pull (not to mention the whole safety thing and the potential consequences from law enforcement)

After you've had an initial dyno tune then have refined things with street tuning it's normal to put the car back on the dyno and do partial throttle/full throttle pulls in 4th and even 5th gear to verify the tune... the longer gear means the car spends more time at each rpm point allowing for a greater amount of data to he collected, not to mention it will show any gaps or rough spots in the tune that you normally wouldn't feel on the street.

 

It's a matter of time really, I don't have the money for a quality turbo, and will likely be off on a internship or otherwise before I do. I am using setting up the fueling systems and fuel maps and such as a boost to my resume, and want to have it completed in time to include on my resume when applying for internships. My previous internship at NASA Ames was in part due to my mechanical, electrical and programming experience. The job before that I got because they specifically asked in the interview if we were mechanically inclined, and I was able to give changing my clutch as a ready example. As it turns out, for my specific sub field of computer science, experience like this is actually decent leverage into a job. I am considering exploring internships in the automotive industry (I have interviewed with Tesla Motor Company, but was unable to meet the timing of the internship they were looking for, intend to interview with them again.), ANY sort of automotive electrical experience is gold in that sort of job market.

EDIT (Didn't see new post)
Yeah, I am still researching options with the dyno tune. If it comes to it I will have to tune with the nearest dyno. But I am hoping to discover a way to tune without resorting to that immediately (even if it mean sacrificing significant performance because of a ultra conservative tune.) Luckly there are a number of abandoned highways, and even long even inclines (that I could use for additional loading in 2nd gear) in the area. At the end of the day though, I need more research to determine that direction.

 

I want to intern with NASA... lucky bastard

 

i would much prefer to buy a used name brand turbo than a new ebay unit. thats just me.

my first turbo honda ever was a stock block z6 back in 2003/2004. ran it on a straight t3 60 trim. i think it was one of those thunderbird .60/.63 turbos. 8-9 psi was gravy it ran great. above 10-11 psi i would lift the head and fill the overflow. was tuned on uberdata at the time, no fmu so i was able to pull timing.

there is some first hand experience. use it as you will.

i do agree though that a 57 trim is pretty big for a stock single. i tuned a y8 for a friend a few years back with a 57 trim .63 and it was laggy, didnt hit 10 psi till mid 4000 range iirc.

 

I am actually going to start looking into different choices for used OEM turbos after I get it going with this ebay turbo. Once I get something running I can use on a resume, the focus is going to shift to refining the build, starting with the turbo.

Does having a slightly laggy turbo help with fuel economy? Logic would imply that if you don't boost until high up, you would use less gas in normal driving, even when trying to pass cars and such. If so, lag would be a worth while trade off for me. Most cars I have driven that where stock turboed would slip into boost going up hills and in mild acceleration and such.

Also yeah, NASA was an amazing experience. The people I got to work with where beyond comprehension.

 

The problem is when you swap to something like a straight t3 60 trim everything will have to be redone, from the downpipe to the intercooler piping. See the problem with that?

Hell if I still had one of my numerous ford turbos (straight Garrett t3 60 trim) I'd give you the damn thing just so you wouldn't use the eBay turbo. Trust me, one day that eBay turbo will wind up as a door prop when it fails (not if)

 

eBay stuff is really mediocore quality. There is no way around it. I have an eBay Steering wheel and it's just a big pain in the butt. Unfortunately I haven't found anything good to wrap my OEM one with yet.

But onto the turbo, it all sounds right to me. But I've heard 200 HP on a D-series stock block and head to be the limit. If you are doing this just to learn, I know a guy who did something similar. He turbo'd a Y7 and just did street tuning on crome. Probably 160~180 HP, but it was a really good learning experience to install and tune it himself. Now every set up just gets better and better.

 

As for having to change things, from my understanding the flange on the turbo I purchased is fairly common. Also I own a welder so if it came to it I could weld on a different flange fairly easily to the downpipe.

It will be interesting to see how long the turbo lasts, if it lasts long enough for me to learn a few things and find a better turbo, great. If not, I feel I will still come away with a lot of knowledge and most of a turbo setup ready for a proper turbo.

I'm glad to hear that peoples first hand experience is within the realm of what I thought going into it. ~200 hp with a conservative tune, but with some lag.

A few posts back people mentioned buying used and rebuilding, has anyone had any good experience with that? I was gonna start researching that option when I got everything else set up. Also, and I think this is probably a pipe dream, I have heard you can take the replica knock off turbos, and then rebuild them with a quality rebuild kit, and end up with something decent? I don't really see that flying though, since I assume the bearing sizes and tolerances and such are in two different galaxies.

 

Most used turbos don't need to be rebuilt

 

1. That's a case-by-case basis. Just because someone is selling something that "just needs a rebuild" doesn't mean it can actually be rebuilt. For those cases, 9 times out of 10, it costs more to rebuild than to get another unit entirely... Otherwise, honestly, I'd think the seller would just "rebuild" before selling, since they were able to diagnose it so thoroughly .. There are many turbochargers that may seem as though an internal rebuild is in order, only to find that the hard parts are damaged too.. Caveat Emptor.

2. Yes, you are pipe dreaming. Most of the eBay knockoffs can't accept the newer internals with any longevity (though I admit, they are getting better). But once again, its throwing good money after bad. If you're getting ready to go to NASA, find a beater, or another car to drive while you go through your automotive turbocharger "experiences". Life will be a LOT easier that way as you find which direction you want to follow. Its not worth rushing, only to get stranded before getting to the internship because you "didn't have time to get the right equipment".

 

I mentioned in the first post I have alternative transportation. haha. I am rushing to get this on my resume, and possibly save a few thousand in tuition by using a turbo install (even if short lived) as elective directed study credits, allowing me to finish one of my degrees a semester or two sooner. If I wasn't prepared to handle a broken down car for a couple months I wouldn't be considering this.

That's what I thought about the turbos, thank you for confirming. In a random stroke of luck, my buddy randomly decided to part out his talon. With that is two turbos, one that is rebuild-able (on good word, though I will check into it myself as well), and a working turbo he upgraded to about a year ago. So that may end up being the direction I go in. As well as injectors and fuel pump.

 

So I found a really good deal from my buddy who has a 14b in need of a rebuild. (Still boosts well, just has some shaft play.) So I am going to pick that up, and rebuild that. That way when/if the ebay turbo I got starts to go, I will have an OEM quality turbo, that is better sized to swap in.

Good stuff.