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trying to I D this engine

3K views 14 replies 6 participants last post by  jzxcrx 
#1 ·
D15B
1457755

Pretty sure its a replacement engine in my 91HF.
With my search, "D15B" I come up with various possibilities. Can I narrow it down somehow?
Thanks
 
#4 ·
Whoo. Gotta brush up on posting pictures.

Yeah, my searching is coming up with ''V-tec" or non V-tec for this engine with the block number.
Could have something to do with which head it has on it? I really don't know s**t about these engines.

Here is the before/after of the VC repaint. Stripped it and used Duplicolor Engine Enamel which is my standby spraycan paint for a lot of automotive stuff.



 
#5 ·
Assuming the engine was used as a longblock replacement, it's just an 88-91 D15 non-VTEC. Probably the closest approximation would be a D15B2. For whatever reason Honda only used the 4-digit codes in Japan, so D15B got stamped on many different engines over there. The manifolds are original to your HF.

If you look at the head code (PM3, PM8, etc) you'll be able to narrow it down further. But I would not suspect anything special. It's possible that only the shortblock was swapped and the HF head was retained, but that almost never happens.
 
#8 ·
jfrolang said:
For that engine in its original configuration, probably about 92.

In your car considering the HF manifolds, about 60.
I would guess it at a little more if it has the PM3 16 valve head - maybe about 75-80 - probably not more than that - could also depend on the ECU - what ECU are you running? PM-8?
 
#9 ·
Is it an 8 or 16 valve head? If it's a short block swap rather then a long block swap I would expect low compression unless the builder knew to CC the head and shave as necessary to set the compression ratio to stock or higher.

If the Injectors are not properly paired with the ECU that could cause poor running issues.

If this is a long block swap with all other parts left alone I would expect slightly more then stock HF peek HP with a slight loss in low end torque. Performance would also be dependent on what transmission you have. If you have the stock HF transmission you might get slighter higher MPG in 4th gear rather then 5th.

Mike
 
#14 ·
jzxcrx said:
What version is it ?
Maybe I'm thinking too literally about referencing my engine to these lists and charts.
as far as I have been able to determine, all of the non-VTEC JDM D15B engines had carbs, either single or dual - we have swapped many of these over the years and have never seen a single carb model - all of these carbed D15B engines were around 100 hp (91 for the single carb) - my guess would be that your JDM D15B was a dual carb model, which single or dual doesn't really make any difference since the original D15B6 intake manifold from the HF was swapped onto the JDM D15B - I would also guess that the HF PM8 eight valve head was not swapped onto the D15B as the resulting very low compression ratio for that combination wouldn't produce much power - the original carbed engine used a mechanical fuel pump which was actuated by an additional lobe on the camshaft - the pump was located on the back of the head near the distributor end just in front of the EGR valve - if the engine currently has the PM3 sixteen valve head that came on the D15B, you should be able to see a block-off plate, which someone had to fabricate and install where the fuel pump was removed, like the one in the attached picture - I would assume you are running it with the original HF ECU which was the PM-8? - otherwise you would be getting a check engine light and a code 12 for the EGR valve - with the relatively small intake manifold and small throttle body from the HF along with the PM-8 ECU, I would guess the hp would be around 90, if that.

 
#15 ·
That's something. Thanks for the input.
The head does have the block-off plate for the mechanical fuel pump. Means it's a 16-valve head.
Never saw that, as the valve cover must've been off the original Hf motor.

jlicrx you were exactly
 
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