Honda and Acura Car Forums banner

1 - 19 of 19 Posts

·
Registered
Joined
·
624 Posts
Discussion Starter #1
Ok, I'm building a block to match up with my built head, and I'm looking to up the compression for some extra power. However, I'm not made of money, and this car is my daily driver, so it needs to stay reliable too.

First qustion: what is the highest recommended c/r for a daily driver, and are there any OEM pistons from another D-series that would give me a managable c/r? Remember: daily driver. (The highest octane rating available to me here is 91 pump fuel. Race fuel is available for a little extra trouble and a LOT more money. The octane rating on that is over 100.)

2nd, this is a little bit off topic, but just an idea: I got the block for dirt cheap, and considering that I got the block, tranny, stage 2 clutch, and all the accessories but P/S pump for $250, the block, being damaged and in need of being bored 20 over is pretty much a throwaway.... I was thinking about getting a D15 block, and building that for high-comp. and putting my D16Z6 VTEC head on for a built VTEC 1.5L with an EX tranny that revs to over 8k. Good or bad idea? What would that require? I'm only considering this because the D15 is more stable at high rpms and I've heard that it has a better rod to stroke ratio for a smooth powerband.
 

·
Registered
Joined
·
5,517 Posts
12:1 on 91 octane for a daily driver can be done, but requires your tuning to be dead on. 11:1 is more manageable.
 

·
Registered
Joined
·
11,248 Posts
93civicdude said:
I was thinking about getting a D15 block, and building that for high-comp. and putting my D16Z6 VTEC head on for a built VTEC 1.5L with an EX tranny that revs to over 8k. Good or bad idea? What would that require? I'm only considering this because the D15 is more stable at high rpms and I've heard that it has a better rod to stroke ratio for a smooth powerband.
I wouldn't bother with a d15 block unless it was the jdm d15b. However you can get a complete jdm d15b for about $450 and it has a z6 head and uses d16 rods :) Bore it over to get some of your displacement back and you are doin' somethin' :)
 

·
Registered
Joined
·
624 Posts
Discussion Starter #4
kommon_sense said:
I wouldn't bother with a d15 block unless it was the jdm d15b. However you can get a complete jdm d15b for about $450 and it has a z6 head and uses d16 rods :) Bore it over to get some of your displacement back and you are doin' somethin' :)
Where could I find just the block, and how much might that cost?

I'm assuming that the VTEC d15 and non-VTEC blocks have the same difference as the LS vs. the GSR. Where as the GSR block is better reinforced (sp? lol), and the LS isn't ported for the VTEC oil passage. Am I correct?

Also, why do you say not to go with a American D15b, out of curiosity?
 

·
Registered
Joined
·
11,248 Posts
doubt that you could find just the block, but at $450 for a complete sway, you could always sell off what you don't need. also jdm d15b has the z6/y8 tranny.

I would avoid the USDM d15b2/d15b7 because they have smaller main and rod journals on the crank. The crank is weaker, rods are weaker and only company that makes aftermarket rods for it is crower @$600.
 

·
Registered
Joined
·
624 Posts
Discussion Starter #6
kommon_sense said:
doubt that you could find just the block, but at $450 for a complete sway, you could always sell off what you don't need. also jdm d15b has the z6/y8 tranny.

I would avoid the USDM d15b2/d15b7 because they have smaller main and rod journals on the crank. The crank is weaker, rods are weaker and only company that makes aftermarket rods for it is crower @$600.
Ouch... Good point. Where is it that I can get the JDM d15b?
 

·
Registered
Joined
·
624 Posts
Discussion Starter #8

·
Registered
Joined
·
632 Posts
93civicdude said:
Forgot the .com in your link. :p

Thanks, I found it. 435+ shipping. I bet shipping is a bitch...
u like road trips and rainy weather? no this is not a come-on, lol
there is a place in portland oregon called Auto Adventure.
i bought my jdm d15b there 1 year ago for $500 even. everything from oil pan to valve cover, but no tranny of course.
i dont know if they ship and how much it would be, but if your in northern cali, mabey it would be worth it.
USUALLY[this is what i have heard many times as being a fact, from different sources mind you].
japan does NOT ship an engine to US market if it has over 50k on it, so if you do buy a jdm d15b that has been shipped from nippon then your looking at a pretty young engine.
thats my insight.
 

·
Registered
Joined
·
624 Posts
Discussion Starter #11
Well, it looks like I have a couple options if I wanted to get a JDM d15b...

Now, in theory, it seems like a good idea to put a more rev happy bottom end on a honda engine, but with the potential of a D16Z6 head and my cam, or really any cam, will the revving ability really make up for the extra work and money?

I've been playing with my car a little bit trying to figure out where it pulls the best through the powerband.

It's weird cause 1st gear seems to drop off at 7500, but 2nd doesn't seem to stop pulling until 8000. (I'll never rev it higher than that for fear of blowing up my engine.) 3rd gear, wrapping out at over 100mph seems to pull the hardest up until 7800 or 7900. I've never got to the end of 4th gear because at that point I'd be going WAY too fucking fast!

So the d15 would be able to rev higher, but will it really be able to rev high enough to make up for the extra stroke of the 1.6 liter version? I'd aim for a 11.5:1 c/r on either setup.
 

·
Registered
Joined
·
11,248 Posts
There are more things that come with the improved rod/stroke ratio than just better stability at high rpms.

http://www.grapeaperacing.com/GrapeApeRacing/tech/connectingrods.pdf

Read the pros/cons of longer/shorter rods. A lot of other info like this available on the net :)

IMO to really get the most of the longer r/s ratio, you should bore as well. I believe you can do 76mm without problems, but sleeved w/77mm is better (put you at 1576cc). Get the head opened up to match the larger bore and get quench pads added in as well. Possibly go 1mm oversized on the valves, get a *GOOD* set of pistons, balanced/chamfered crank, crower rods (yes, I know they are expensive, they they are lighter than eagles), etc... etc... Add on a good header (like SMSP), IM (Edelbrock), etc...

If I were in a position to build any d-series that I wanted and do whatever I wanted, I would most likely start with the jdm d15b or find some way to destroke a d16. However I understand that budget is a big concern.
 

·
Registered
Joined
·
624 Posts
Discussion Starter #14
Alright, I've decided to stick with the D16 block... But I need to find some pistons. I was thinking D16A6 pistons with a thin head gasket... That should give me close to 11:1 c/r, right? Where would be the best place to find those at 75.5mm oversized?
 

·
Registered
Joined
·
350 Posts
your sig is to big
 

·
Registered
Joined
·
819 Posts
93civicdude said:
Alright, I've decided to stick with the D16 block... But I need to find some pistons. I was thinking D16A6 pistons with a thin head gasket... That should give me close to 11:1 c/r, right? Where would be the best place to find those at 75.5mm oversized?
Yes, here's an update on my situation. For me, 12.7:1 is just too high, it was cool at first but as time went on and as i read more and more about it, it's not something i want to do as of now. SO, i'm looking for a6 pistons as well and the only place that i've called so far is Honda, they're $63 per piston so that adds up to: $252.00. WOW!!! rings are $45 each also. So if i cant get a hookup from one of my honda buddies, i might as well just sell the block and start over! 8(....8)
 

·
Registered
Joined
·
11,248 Posts
93civicdude said:
Alright, I've decided to stick with the D16 block... But I need to find some pistons. I was thinking D16A6 pistons with a thin head gasket... That should give me close to 11:1 c/r, right? Where would be the best place to find those at 75.5mm oversized?
Don't know that you could squeeze 11:1 out of that... Maybe 10.7:1 or so... Maybe if you add some flat faced valves, etc...

As for pistons... www.acuraautomotiveparts.org
 

·
Registered
Joined
·
11,248 Posts
mRek9R said:
Yes, here's an update on my situation. For me, 12.7:1 is just too high, it was cool at first but as time went on and as i read more and more about it, it's not something i want to do as of now. SO, i'm looking for a6 pistons as well and the only place that i've called so far is Honda, they're $63 per piston so that adds up to: $252.00. WOW!!! rings are $45 each also. So if i cant get a hookup from one of my honda buddies, i might as well just sell the block and start over! 8(....8)
Hastings rings... About $85-90/set from one of our sponsors... www.kteller.com .

Check some of the online honda sources like www.slhondaparts.com . Much cheaper than the dealer.
 
1 - 19 of 19 Posts
Top