Honda D Series Forum banner

D15B vTec identification??

16K views 35 replies 15 participants last post by  1994solSI 
#1 ·
How do I verify if I actually have a Vtec engine?

I checked out several links, and did a little extra research. If I am not mistaken, my JDM engine is a vtec. It is marked with D15B only, the non Vtecs seem to have a trailing number as in D15B6. This would explain the mysterious block off plate on the back of the head on the passenger side (about 2inch square). I am betting it was in a car that had no Vtec components so they blocked it off and it is only using 8 valves (vtec off). I may have most of the components in the car, might be a cheap upgrade to turn that thing on?

History: I bought the car, a 1994 Civic Si Hatchback, a couple days ago. When I looked at it it had an Integra LS engine in it with perf add ons. I was looking for a commuter car with better mileage. The owner knocked a thousand off if he was allowed to pull that engine and exhaust and replace with the JDM in his sons car that was recently totaled, they had just installed a JDM in it. I took the deal.

If I fell into a cool deal, and I turn on the vTec, would I lose much in the way of mileage? Any way to verify if it has vTec? From what I hear some JDM engines with vTec were not marked with the big vTec valve cover.
=====
D15B
...
Displacement (cc): 1493
Power (bhp@rpm): 130@6800
Torque (ft/lbs@rpm): 14.1kg/m@5200
Compression Ratio: 9.6:1
Bore (mm): 75
Stroke (mm): 84.5
Cam Design: sohc
VTEC?: yes
OBD:
Year(s) Produced: 1991-1999
In the following car(s): Honda Civic VTi (EG4)
 
See less See more
#4 ·
well, a vtec cam will have three lobes on the intake, a primary, a secondary, and the vtec lobe, then there will be two exhaust lobes. so there will be a total of five lobes between each journal, this is on a sohc vtec. The vtec works hydraulically, when the ecu activates it, a solenoid opens and lets oil flow through the rockershaft, pushing a tiny piston into a floating vtec rocker arm, thus locking it together with the normal two intake rockers, so all three begin to ride on the larger vtec cam lobe....ingenious, and quite simple really....so many people make such a big deal out of it, vtec is primarily a marriage of two engines, an economy engine with a mild cam at lower rpms, and a performance engine with an aggresive cam at higher rpms....best of both worlds all in one engine
 
#6 ·
D15B also came non vtec....
http://www.cr-x.org/home/jdmspecs.html

there should be a solenoid on the head if its vtec
he knows that, but he thinks somebody pulled it off and put a plate over where the solenoid goes...to run it in a non vtec application, why somebody would do this is beyond me...lol So, just pull the vc and check, take about five minutes to do...
 
#7 ·
Good lord.

Most simple way; spark plugs facing front=VTEC, facing back=non-VTEC. Only exception is the D16Y7; it faces the front but is non-VTEC.

The JDM D15B came in a non-VTEC variant also(similar to the D15B7). I believe SohcInWa or someone else has this.
 
#9 ·
Take off the valve cover? why bother... If you motor has this it's a JDM D15B Vtec...
i guess you did not read. the kid said he thinks that the previous owner removed the solenoid and put a plate over it so no this head (if v-tec) does not have it. it should not have a plate if not v-tec it should be indented and wierd shaped. if it is flat then it has had a plate put on
 
#14 · (Edited)
or just look at the stamp

d15b vtec
d15b7 no tec

CodeDisplacement Power Torque Compression Bore Stroke Cam Design VTEC? OBD Production
D15A2 1488 58 0 0 sohc no 0 1984-1987 CRX HF (Carbed)
D15B 1493 130@6800 14.1kg/m@5200 9.6:1 75 84.5 sohc yes 1991-1999 Civic VTi (EG4)
D15B2 1493 92@6000 89@4500 9.2:1 75 84.5 sohc no 0 1988-1991 Civic DX/LX, CRX DX
D15B6 1493 62@4500 83@3000 9.1:1 75 84.5 sohc no 0 1988-1989 Civic HF / CRX HF
D15B7 1493 102@5900 98@5000 9.2:1 75 84.5 sohc no 1 1992-1995 Civic DX/LX
D15B8 1493 70@4500 83@3000 9.1:1 75 84.5 sohc no 1 1992-1995 Civic CX
D15Z1 1493 92@5500 97@4500 9.3:1 75 84.5 sohc yes 1 1992-1995 Civic VX
 
#16 ·
or just look at the stamp

d15b vtec
d15b7 no tec
That's not true. There is a non-VTEC JDM D15B(similar to the B7) and three different versions of the VTEC D15B's(3-stage, VTEC-E, and of course the regular old VTEC one).
 
#18 ·
Looks like NeonPinHead had it right. I pulled the valve cover and found only four lobes for each cylinder. Looks like I have a non-VTEC, but its fun anyway.

How do I order parts for this thing? AutoZone peeps seem to only be capable of looking up parts by model and year. Is there a Model and year I can give them for a non-VTEC D15B engine? In particular I need new plug wires.

Thanks again all,
Sam
 
#24 ·
Thats basically just the same motor that comes in the DX, so you could up parts for the same year, just a DX model. I'd throw in an A6 cam to wake it up. For the time and money to put a vtec head on it, you'd probably be happier and much easier to put in an A6 cam or even an aftermarket regrind. It prolly won't hurt mpg that bad if any, and get it tuned. With a good tune and better cam it'll be nice.
 
#25 · (Edited)
Since a VTEC runs high efficient in low rpm's wouldnt it get better fuel mileage than a cam cut for performance?

On searching it looks like I can make this a VTEC JDM by installing a Z6 and p28ecu chipped as p08. The car is an Si so the harness should be set. I would assume the use of the Z6 head gasket and manifolds so everything jives.

I'll look into that cam, but fear killing my commute mpg. I am only really concerned with passing power that I seem to lack with the current engine build out.

EDIT: I am an air cooled VW nut for the last thirty years, so my applied knowledge may be skewed. Any and all advice in changing my engine orientation much appreciated.
 
#26 · (Edited)
Well in all honesty, I have a 90 CRX Si and had a stock A6 non-vtec, got high 30 mpgs. Swapped to obd1 with a rywire harness and put on a Z6 head, and before all the local stations started running 10% ethanol I got 43 mpg about 75/25% hwy/city. And, that was with a cable Si tranny, a little shorter geared 5th than the hyrdo Si tranny (IIRC).

Now, transzex on here made around 53 mpg on a D15B8 (i think), its all in the tune man.

EDIT: Also, welcome to the Honda community. You're on a good site to find info on.
 
#28 ·
Swapped to obd1 would'nt apply to you, since you are obd1 already. OBD1 is 92-95 wiring/ecu. Rywire is a company who makes conversion harnesses for us obd0 guys, amongst other stuff. Tuning comes in as using a software program, such as Crome or buying a Hondata S300 ECU to tune your fuel and timing maps.
 
#29 ·
Many thanks! So tuning is related to the same think I do with my megasquirt in my FI project bug engine. Since there has been a nonV engine placed in this car the ecu may not be what its supposed to be, I need to verify that. Harness should be good. Could I go with a DOHC VTEC with my obd1 harness on this engine? Any benefit?
 
#30 · (Edited)
OK I know this thread is a month old but there is some just plain wrong info in here . First the sohc vtec cam does not have five lobes per cylinder as stated earlier in the thread it has only three the intake and exhaust are run by the same lobes on the cam . If you don't believe me I'll post pics of my skunk2 cam . two your last question NO a dohc vtec does not come anywhere close to bolting on to a d-series block
 
#31 ·
^^^ you're an idiot
exhaust lobes cannot run intake valves...or vise versa
take 5 steps back and go read how motors work

also just to throw more into the mix
there are plenty of 96+ (95+ in japan) jdm d15b's with y7 heads
which would equal d15b non-vtec
 
#34 ·
skunk2 doesnt make ANY parts for non-vtecs! some parts made for a v-tec may infact fit a notec but was not made for it.

actual reply mail strait from skunk2:

Thank you for contacting the Helpdesk at Skunk2 Racing.

Skunk2 only manufactures performance parts for vtec engines. The one exception to this is valve springs and retainers for the non vtec B18A/B.

I would recommend contacting a couple large parts distributors to see if they can find you someone that makes parts for that engine. You should start by contacting Options Auto Salon or Nopi. Those guys should be able to search across multiple manufacturers for your parts. This should hopefully save you some time on your search, rather than contacting each manufacturer individually.

If you have any more questions regarding Skunk2 products or policy please let us know. Thanks.

Brian Nichols
Customer Service
Skunk2 Racing
2050 5th St. Norco, Ca

Thanks for using the help desk, if you have any further difficulties or are required to respond to your request, please login to the help desk
 
#35 ·
I don't know what cam the guy was looking at when he posted that vtec cams don't have 5 lobes and they use the intake lobes for the exhaust lobes too...lol He claimed his skunk2 cam only had three lobes per cylinder.... I only posted my original post AFTER I went out to my garage and looked at my z6 vtec cam....lol
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top