fogged306

Here's what I'm doing and thinking of doing. I have a JDM vtec-e (d15z1 equivalent) that is going into my 92 LX shortly. What I would like to do is put a turbo on it that would not affect the fuel mileage of this motor when I stay under 2k (normal driving) and would give me some extra power for some track fun.

Heres what I'm thinking so far (have not done ANY research yet, just here to see if its even feasible) I just put a turbo kit on a friends integra last year that had a plate with 2 injectors that went inbetween the TB and the intake manifold that only sprayed under boost. I was thinking of finding a system like that with a turbo that only spools right at the vtec point, so that when I stay under roughly 2k, the turbo will have no effect on the mileage of the car. When I take it to the track, I'll just fill it up with some premium (and octane booster If I have to) and go.

The only hang-up I see here is I don't know the stock compression ratio of the d15z1.. is it high, or low enough that I would be safe running a small amt of boost through it?

Any other flaws problems you see? anyone heard of a kit with the injectors like that?

turboteg90

the vtec-e is made for fuel economy not power..your are gona blow that engine the second you hit boost

Relic1

Z1's CR - 9.3:1
but the head flows very differently than a normal a VTEC head.
pre-VTEC, it's actually 12valve mode that's setup to increase swirl that helps control the higher A/F ratios, post-VTEC it's 16V mode which we all know and love.

IF tuned right it will work, but you'll loose the controlled lean burn mode that makes the VX get such good mileage.
plus tuning is going to be tricky and seriously necessary. strapping in an extra set of injectors to turn on when you hit boost is crap, get a chipped P28, a wideband, larger injectors/fuel pump, a tuning program and do it right.

honestly you're better off going with a DIY turbo kit on a D16Z6/P28 with a good tune and larger injectors/fuel pump.
Much more stable, much more people have done it and it will get decent mileage if you tune it right.

fogged306

How would I lose the lean burn? I will still be keeping the LAF in place before the turbo and with the right turbo, I should have 0lbs boost before my target RPM, so the LAF will see no change in A/F over a normal (unboosted) z1. I definitely don't want to go with larger injectors, I know the ad-on injectors is a pretty crappy setup, but its those or nothing.. the mileage is much more important to me than the boost is... I just want my cake and eat it too. I'm not looking for huge numbers here, if I can get 180-200 at the crank I'll be more than happy. I'm not sure how feasible that is with the setup I want but I'll be checking into it... I'm a v8 guy (always N/A at that) so modding a 4cyl and boost are somewhat new to me. I learn fast though, I've been building engines for years.

Thanks for the C/R info though.

Edit: now I see why you said I'll lose the lean burn.. the p28.. also not an option for me, I'll definitely be keeping lean burn and the p07, thats the whole reason I bought this engine.


Modified by fogged306 at 10:06 PM 7/3/2008


Modified by fogged306 at 10:08 PM 7/3/2008

2000siturboR

heres an idea keep that car for fuel mileage and go get any kind of civic from 88-95 i say as high as 95 is because obd2 sucks. you could probablly find something pretty cheap and start with that rather than going through the the pain of making that motor work.

sohc_coupe24

First off, it is entirely possible to boost that vx of yours. Is it the best motor to boost? Of course not. But hey, if you want to do it, whose stopping you. As for fuel economy, its all in the tune. Get yourself a reputable tuner and go from there. As the others suggested, the vtec-e motors are a little trickier to tune. Personally, my turbo d (d16y8) is still getting 32-35 mpg highway.

92VXeg

iTrader: (1)

your going to have to boost the **** out of that thing to get an extra 100-110 hp...dont they come stock at 92hp

fogged306

92 hp starting point eh?... haha great. Since boost and 4 cylinders is relatively new to me (as far as digging into them for power goes), how much boost can I get away with on pump gas (93) and stock internals 6lbs, 8lbs, more, less? How much power can I make with that relatively mild amt of boost, roughly, with the set-up I'm looking for?

Also, getting a second car is also out of the question too. Thats what I'm trying to eliminate. I have my mustang (race) still and I have another daily driver and I want to sell them all and just have one car on the road. Also, with my current engine in the lx, I'm getting about 42MPG combined (I drive for FE), and thats mostly city, so when I do the VX swap, I'm doing it to make that number go up.. the boost is just an afterthought, I'm just thinking I can squeeze a couple horses out of that engine when I want to have a little fun.. just to stress the point that I'm not willing to do anything to sacrifice the mileage.

Relic1

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fogged306 &raquo;</TD></TR><TR><TD CLASS="quote">How would I lose the lean burn? I will still be keeping the LAF in place before the turbo and with the right turbo, I should have 0lbs boost before my target RPM, so the LAF will see no change in A/F over a normal (unboosted) z1. I definitely don't want to go with larger injectors, I know the ad-on injectors is a pretty crappy setup, but its those or nothing.. </TD></TR></TABLE>
not if you find someone who knows what they are doing. (or tune it yourself and learn a lot before diving in) eCtune has the option to use a wideband input for closed loop, and is in development for the ability to follow the lamda table during closed loop. So you could tune it so it enters a quasi-lean burn mode when cruising and it exits all by itself when you push on it. Not quite the true lean burn mode, but it's damn close.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">the mileage is much more important to me than the boost is... I just want my cake and eat it too. I'm not looking for huge numbers here, if I can get 180-200 at the crank I'll be more than happy.</TD></TR></TABLE>
highly doubtful with your setup. The most I'd go with this setup is 6psi, 8 if you have a really good tuner and have another car for when this one pops. IMO, you're talking in the 160 range max.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">I'm not sure how feasible that is with the setup I want but I'll be checking into it... I'm a v8 guy (always N/A at that) so modding a 4cyl and boost are somewhat new to me. I learn fast though, I've been building engines for years.

Thanks for the C/R info though.

Edit: now I see why you said I'll lose the lean burn.. the p28.. also not an option for me, I'll definitely be keeping lean burn and the p07, thats the whole reason I bought this engine.</TD></TR></TABLE>
there was a guy on here that had a turbo HX (the later model version of the VX) that pulled down 165hp, but he got rid of the ECU and went with a tuned P28, larger injectors and an electronic boost controller to keep things in check.

fogged306

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Relic1 &raquo;</TD></TR><TR><TD CLASS="quote">
not if you find someone who knows what they are doing. (or tune it yourself and learn a lot before diving in) eCtune has the option to use a wideband input for closed loop, and is in development for the ability to follow the lamda table during closed loop. So you could tune it so it enters a quasi-lean burn mode when cruising and it exits all by itself when you push on it. Not quite the true lean burn mode, but it's damn close.

highly doubtful with your setup. The most I'd go with this setup is 6psi, 8 if you have a really good tuner and have another car for when this one pops. IMO, you're talking in the 160 range max.


there was a guy on here that had a turbo HX (the later model version of the VX) that pulled down 165hp, but he got rid of the ECU and went with a tuned P28, larger injectors and an electronic boost controller to keep things in check.</TD></TR></TABLE>

Ok this is some of the info that I was looking for, thanks.

Lets say I kept the p07, did the injector plate and ran 6lbs of boost, what kind of numbers are we talking? I'm also wondering if I can get a custom ground cam(s) that would give me a little more aggresive profile after the vtec point. That way I could still have the stock vx lobes down low, and then some better tailored ones to fit my application better for after vtec and turbo kicks in.

As far as a tune goes, what can I do with the p07?.. I definitely want the maps unchanged before vtec. I'm keeping it no matter what, so I want to see if its workable. Basically I'm looking for the most dramatic difference between before and after the vtec engages.

Pretty much its like this.. If I was really looking to make a lot of power, I wouldn't start with a d15z1 and a p07, I know that, but thats not the case. I just want to maximize here.

Relic1

right now the P07 is a dead end. not much you can do with it.

If you want to go with custom cams you'll need to tune, which means dropping to a chipable VTEC ECU like the P28.
You'll also want to look into a boost controller. Since under light loads on the highway, a smaller turbo (like you'll need with the Z1) will start building boost and push you way out of the mpg range of the maps.
eCtune has an option to use one of the unused outputs as an electronic boost controller, so you can control what you have. Also you can use one of the other configurable outputs to open and close a solenoid on the wastegate on the turbo.
This way it will not build boost when you don't want it to. But when you want to it will be there for you. Keep in mind this is not exactly an off the shelf setup, nor something that can run on a chip someone sends you. It will require some dyno and street tuning time.

One other thought, with eCtune controlling the boost, turbo lag off the line (when you want power) should minimal with the anti-lag setup and the launch control.

(I've thought about this project, just never had the time/money/space/car to do it)

fogged306

All excellent info, thanks a lot! I'm going to have to look into what I can do with the p28 and eCtune as far as making my own lean burn, and how to do it. Where's the best place to learning about the eCtune, and how to use it? But now I know the limits of what I have and what I can do with them, so I can definitely start piecing together a set-up.

BlackDeuceCoupe

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboteg90 &raquo;</TD></TR><TR><TD CLASS="quote">the vtec-e is made for fuel economy not power..your are gona blow that engine the second you hit boost</TD></TR></TABLE>


I knew a guy that boosted a HX in like 2002 - sort of a pioneer...

It had some teething problems, but he finally figured it out!

Nowadays they make kits for them.

Slowboy is a little pricey @ 3800 bones - but it IS possible to huff a VTEC-E...

JoeDel

ok let me get this right you want to boost to make the car a little more fun but you want to save money by keeping the mpg, i dont want to be rude but have you figured out how long it will take driving it to save enough money on gas to offset the cost of this custom setup your looking into? i mean by all means it is your car do what you want, but it seems like it would be easier/ cheaper to keep your engine and boost it with slightly less mpgs now but less headaches down the road. anyway just my 2cents good luck with whatever you decide.

riceburnerryan

it sounds like a lot of work, when you can get a D16Z6 and still have good gas mileage... a friend of mine had a boost setup on a b16, yes i know its a totally different engine, but he was getting 36MPG and he was at 15pounds daily... it just depends on your tune... i was talking to a guy on here and he has a SOHC turbo setup and he said he had a tune where he was running a lean map and he was getting about 40 MPG... you can get the Z6 and still have good gas mileage and more power...

Relic1

http://www.eCtune.com to read about it.

no reason why you couldn't see 45-50mpg with this setup, that and 150hp to the wheels. It all depends on how far you want to take this. To get to those figures it's going to take some serious work and tuning to get it so it will last.

fogged306

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Relic1 &raquo;</TD></TR><TR><TD CLASS="quote">http://www.eCtune.com to read about it.

no reason why you couldn't see 45-50mpg with this setup, that and 150hp to the wheels. It all depends on how far you want to take this. To get to those figures it's going to take some serious work and tuning to get it so it will last.</TD></TR></TABLE>

Thanks again for all the info and pointing me in the right direction, I'll be doing my homework now for a while and see what I can come up with.. won't be too soon (few months), but I'll be sure to revive this thread when I get the project rolling. Hopefully your still around by then if I need some more pointing.

jt223539

When I had my 93 Vx I placed it on the dyno and got 68whp out of it, my motor had no intake but had a Skunk2 Mega power exhaust, oh and it was approaching 200k on the odometer. So as for getting any decent horsepower numbers out of it good luck.


On a side note, someone told me that if you rebuilt the head of d15z1 you could get it to easyily rev to 10k with little to no problem, is that true?