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93 maybe 94 coupe
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Discussion Starter #1
Ok so no pics yet but I have all that's needed to begin. The plan is to add compression, cam, and head flow to a once carbed JDM d15b with a y7 rocker conversion on a y8 head for about 11:1 and since Delta is in town, perhaps a 260 regrind.

Done w the research, dying to get going. Just a couple questions left.

Will a y8 manifold really be too much or should I stick w the b7 style mani I run currently since there's no high cam and I'll be shooting for a few less revs than if I was doing a proper, built bottom end minime? Y8 mani is also auto and will need some modifying.

Shooting for ≈[email protected] or 120-130 on dyno and to be within workable distance of cracking into the 15's w street tires in a mildly lightened 93 coupe.

Not looking to over cam, don't like the dynos of 272 cars. (Even if they are 1.6) If it's all on after 6.5k that's too late. Does it sound like this should equate to something near my goals?

I'd rather have a 5-7k powerband flling off by my limiter than power I can't rev through enough to use. Kinda like one would want a road racing motor, largest area under the curve I can achieve.

Peak numbers are for posers! I don't drive anywhere on dynos.

Thoughts and feedback? Pics by next paycheck!
 

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93 maybe 94 coupe
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Discussion Starter #2
Buddy says my goals are unrealistically low.
 

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Brokedick Millionaire
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40,252 Posts
WTF are you wasting all that money on?

One thing, unless boosted or huge cam, OEM Y8 intake hurts overall performance, stick with Z6 intake.

Cracking into the 15's on street tires? Maybe if you are on 155/80/13's at 50 psi....

Lowly 113.5 WHP gets low 15's on 20" MT's...

Oh yeah, big cams or not, close ratios or not, still getting 45-48 mpg.
 

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93 maybe 94 coupe
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288 Posts
Discussion Starter #4 (Edited)
Lol my net expenditure as of now is +100$, I've gotten both complete motors and transmissions (both auto I'm still tryna dump) for a combined cost of 75$ because I pulled em for ppl doing swaps. And I sold the y7 shortblock for 175.

Save it for boost u say, check. One less thing to eff with this time

I figured with a y8 head it's stock intake would be well matched since the smaller engine is gonna rev similar to a stock y8 on the 1.6/reground cam. But I wasn't really looking forward to all the mods it neccesitated, or all the comments that ppl lost mpg. Lost mpg also usually means less throttle response and that too would suck.

I figured it was from ppl taking a runner and plenum volume designed for the approach to a swirl port head and bolting it to a head w a tumble port design. I'm none too big on the idea that u should mirror image port the y8 head for this reason.

Yeah. It flows more and makes power, but is diminishing the effect of the port design also diminishing the supposed bonuses of having a swirl theory closed chamber design in the first place?

If so I can see why it's hands down z6 stuff for a real build.

Edit* or a6
 

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Registered
93 maybe 94 coupe
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288 Posts
Discussion Starter #5
Head off slick and easy, 1/4 turn per bolt til they were loose enough to turn with a busted up thumb (unrelated)

It's gat vtakks yo!



Tdc baby!!



Gross it's got rust and a ridge





Safe n sound

More fathers day fun



Mmmm



Mmmmm



Mmmm


Now it's off to the shop to get cleaned, checked out, and decked flat if needed. Happy Father's day!! I'm freakin FULL!
 

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93 maybe 94 coupe
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288 Posts
Discussion Starter #6
Mo pics


Couple taps and it's off


No mo vtakks


Damn.

Guess that may be my clunk when I hit tarred up cracks or tiny bumps. Compliance bushing looked decent and it didn't look like any LCA bushings were too bad.
 

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D-series Janitor
Front Engine Dragste
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260 regrind is a waste of time unless you have an automatic.

272 is about the biggest you can go without throwing off the rocker arm geometry.

Either keep the stock cam or run the 272 profile
 

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93 maybe 94 coupe
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Discussion Starter #8
Keeping stock, why u think that though? Duration and lift are duration and lift, the motor gives zero f***s what tranny it's hooked to.

Most beast7 dynos I've seen indicate they could turn more rpm than most ppl spin em based on the cam, but then everyone that shoots it to 7500 spins bearings or worse so a 272 cam would be crazy too big and really anything over a stock cam will just put the power where I can't reach it on an otherwise stock motor

IF I end up swapping in a spare motor and putting ARP stuff in the bottom of the d15 w a ported oil pump and mods then maybe the regrinds would come into play.
 

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BATSLOMAN GIVES NO FUCKS.
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don't re-use old head bolts
 

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D-series Janitor
Front Engine Dragste
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Keeping stock, why u think that though?
Because the delta 260 regrind picks up almost nothing in HP and loses torque for $110 or whatever the cost nowadays. They are grinding in pretty lazy ramps with minimal QC which is why they are the price leader . . . I have yet to get a cam from them that all of the valve timing events were exactly on with the cam card (that they don't want to give you).

Duration and lift are duration and lift, the motor gives zero f***s what tranny it's hooked to.
Yes, but an automatic shifts for you when it wants.

You can't put in a 220 @ .050" camshaft and use hardly any of it because the shift package shifts on it's own without input from you. Hence why anything more than a 260 regrind is a waste unless you have an automatic . . . anything larger is going to make peak HP past where the transmission shifts. In a manual you don't have that problem.

but then everyone that shoots it to 7500 spins bearings
That's because plenty of people on the internet have no business building an engine.
 

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93 maybe 94 coupe
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Discussion Starter #11 (Edited)
Lol those guys spinning bearings were doing zero building, unless head/cam swaps count

Feel ya on the auto thing now.

I was thinking the 260 would be basically the same as si cam if one weren't available, or as a replacement for the y7 cam given an si cam is out of the question.

I have no problem w getting cam cards from them although if u can't SHOW UP and chat w em ive heard they arent exactly forthcoming w specs. (And I've never checked vs card)

Honestly, I'm yet to see any 260 cam dynos AT ALL. Done mega searches too. I totally hear ya that the cost/percieved risk to cam isn't worth the gains, but that said I totally trust Delta. They've done right by my family for an entire generation and counting.

I don't believe they even grind the ramps at all, the adjustment for the reduced base circle is what makes the same lobe seem physically bigger, correct? <---no expert
 

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Front Engine Dragste
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I was thinking the 260 would be basically the same as si cam if one weren't available, or as a replacement for the y7 cam given an si cam is out of the question.

Honestly, I'm yet to see any 260 cam dynos AT ALL. Done mega searches too. I totally hear ya that the cost/percieved risk to cam isn't worth the gains, but that said I totally trust Delta. They've done right by my family for an entire generation and counting.

I don't believe they even grind the ramps at all, the adjustment for the reduced base circle is what makes the same lobe seem physically bigger, correct? <---no expert
I could see that . . . basically the 260 regrind being a replacement for an "Si" cam even though obviously a non-vtec "Si" cam didn't exist after 91.

I had a 88dx with a delta 260 and an automatic . . . the main reason I went with the 260 was exactly because of the automatic. Didn't have the space, tools, or knowledge to do a manual swap at the time unfortunately. Made right at 90whp with the delta cam and the MPFI swap with a stock a6 intake (and header/exhaust).

Delta is the definition of you get what you pay for . . . I would run a delta 272 again in heartbeat with another budget setup because I think it's a good value but if I was building a serious all motor or SFWD car I wouldn't use them just based on what I've seen.

Technically any regrind is cutting the base circle . . . it's the only way to increase the lobe profile. I know the 272 cam from them cut almost all the way up the ramp. I ran the 260 cam from them like 10 years ago, don't remember how much was cut.
 

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93 maybe 94 coupe
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Discussion Starter #13 (Edited)
Or like if your yards are picked of a6/z6 parts, but are swimming with d15bx automatics.

I was tryna find a solid a6 cam for literally months and gave up, decided to work with what literally fell in my lap, and hey. Why not.

Studs r reusable but idk how many more times I'll be head swapping this block if this meets my expectations. I thought like all Honda guys reused head bolts though

How am I supposed to get ONE new head bolt for a y8 and the rest for a b7?

Honest q there lol
 

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93 maybe 94 coupe
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Discussion Starter #14
Sold another short block so I'm up another 100 net, bringing the cost of the head to nothing plus a transmission I've yet to find a home for (auto so difficult)

So I'm down to 1 complete y7, my head, and 2 auto trannys. 50 bucks each complete w converter to a dso member if ur local!!

: P

Thinking of swapping in the y7 to put ARP hardware, fresh bearings and some oiling mods into the d15, and so I can build on a stand at a slower pace. Dunno if I'll be happy staying sub 7k w my head/cam swap.

Would chamfers and a oil pump port be in my best interest? (7800 rpm desired cutoff) Heard/read mixed results w diy oiling mods and drilling on bearings seems like a bad idea for a garage bound dude like me that just doesn't want to pay a shop any more than he has to.
 

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93 maybe 94 coupe
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Discussion Starter #16
I've had some. I already have a 140hp 4 banger, in a lighter platform. I'm gonna build the y7 for low rpm operation (stock redline) and boost w a small turbo. Probably a rods and rebuild type thing. 200+ at the wheels and turbo is a good direction for my rice rocket build. The hot hatch on dual carbs can stay na
 
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