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Recent D15b7 turbo builds?

5.4K views 21 replies 5 participants last post by  thompson335  
#1 ·
Hey guys,

I have searched the better part of a day and a half to find a recent d15b7 turbo build i can reference from. I have just a few questions maybe you guys can clear up or shoot me some links you may have seen just recently and i will do the research.

#1: What is the stock block good to in hp #'s?
Im not looking much past 250hp, but would like to have a know threshold. This is a side build to drop in my Del Sol so i can drive the car while my GSR is being built for boost.

#2: I saw multiple post on here saying the stock rods are weak... i know this but I found a set of CX Racing forged h-beam rods for $250. Has anyone dealt with these? Or is there a current manufacturer that I overlooked?

#3 Keeping the same head hust going to go through it and freshen it up and do a little port work but what cam do i use? I have heard great things from delta 272-2 regrinds but I doubt that is my only option, right?

#4: Is it neccesary to port my oil pump for a little hp build like this?

#5: Not running A/C so I am going to run a log style manifold and wrap it in header wrap. Recommended brands? Trying to stay away from ebay stuff...

Im not trying to cheap out because as soon as the GSR is done this is coming out and being put into another shell.

Thats basically it for now. I dont expect to be spoon fed but maybe pointed toward some links that are less than a year old that you may have seen.

Current setup, just in case there are technical questions.

94 Honda Del Sol S
Captiva Blue Pearl (being resprayed in a week)
Stock D15b7

Engine is completely torn down and all looks great for a 87,000 mile motor.

I will be re-assembling the motor with in a week with all new gaskets etc

Using a GT2871r to power it with 550cc injectors and all supporting mods.

Thanks guys,

Austin Webb
 
#2 ·
Most of the b7 build you will find are works in progress. Id say 180-200 depending on how well its tuned. Keep it simple, don't blow it up. There are Sommer really good hmy setups out there that are very simple and get the job done. If you're not gonna build the b7 on some fashion I wouldn't get your hopes up for big power.

Sent from BigJ's mobile awesome device!
 
#3 ·
Im not worried about blowing it up u have 3 of these motors in my shop!

Is the 180-200hp using forged rods? Proper bearings? Upgraded valve springs? Is the intake manifold limiting the air intake volume needed to push more hp?

Thats why i was wondering about current build threads and any know limitations that can be remedied.

Ill ne glad to sacrifice a motor or two for R&D if need be. I can oick up blocks and full motors all day long for $50-$100.

Also, i welcome all suggestions! I have done a few z6 builds, h builds, and quite a few b series builds but none on the d15b7 outside of freshening one up.

Thanks in advance,

Austin Webb
 
#4 · (Edited)
well, since this is a temp build.. anything you do will be fine as long as its temporary..

the issues i see here is the log manifold get restrictive around 6k. but i understand its a temporary thing.

Im interested in those rods you found.. is there a link and also any B series sizings?

The turbo sizing will see power early, but my fall on its ass up top.. I think youll get to 220 area with this set up.

Aftermarket intake manifold wont be needed cuz your forcing air into it, not vac'n air like N/A style. The small TB and manifold will be fine for boost. Like i said, since this is temporary.


This is just my .02

Edited: for being a dumbass and thinking of wrong turbo.
 
#9 ·
Im willing order a set and give it a shot as long as the rods b2 to b7 are the same dimensions. They are rated for 600hp... should hold half that very well at least! Ill have the machine shop notch the block while thye have it.
That's cool I guess, but where are gonona get matching rod bolts? The hungarian guy "liesel" (sp?) sells the custom length one to use vitaras and gives you arp rod bolts to boot. His email is somewhere on here. Trying to navigate his site is a bitch cause it's in Hungarian. I might end up going this route cause it just dawned on me that the parts for my rotating assembly will cost me as much as a set of his rods and vitaras are cheap! My hp ceiling is pretty much doubled. I'd be dumb not to spend the money.
 
#5 ·
You should easily make 180-200 on stock rods in a b7. If its on as good a condition as you say then it should hold up pretty well with a good tune. And I'm pretty sure cx racing didn't make any rods for the b7. You're gonna have to buy a $700 set of Crowers or email the Hungarian dude who has custom length rods for the B7 in production. They are for use with vitara pistons. You're gonna pay more money but you've also eliminated one of biggest weak links on the b7 motor. And no, you shouldn't need to port your oil pump.
 
#7 ·
Hmmmmmm. I never looked into those. Did you? I've never heard although of them. And the b2 and b7 are mostly the same motor.

Sent from BigJ's mobile awesome device!
 
#10 ·
I havent heard much on the CX Racing rods..

They dont say they use ARP Bolts, and adding another 40 bucks for ARP's will get you closer to a set of manley rods for cheap. Or a set of Eagles,Scat.


does CX rods have good rep on here? these are new to me..
 
#12 · (Edited)
They stent stock length. Stock is 137mm and these are 134.5mm that is .1mm off of FJ's 134.6mm rods that the Hungarian guy is selling with the rod bolts you will need.



Even still, the cr will be so low on a straight up b7 motor that without a crap ton of boost it will be slightly turdy. This is why im contemplating using a y8 head to increase my cr.......which is somewhere I don't think you want to go since you have a gsr being built.

Piece together a cheap kit and keep it around 200 HP. Keep it simple. It'll probably last a long time and make a nice dd and then you can "play" with the gsr.

Sent from BigJ's mobile awesome device!
 
#13 ·
when i was researching rods for my z6 turbo setup, cx racing were the main contender, like stated before, not much info on them in the honda community, but if you look around i see them being used with decent results in other brands.

if you aren't pushing extremes i think they would be fine as a step up rod...though that said, I don't think many people make d15 rods, including cx racing
 
#14 ·
Well... now this has my curiosity! When I am done with this motor in my Del Sol it will be going in my spare hatch shell. It wouldnt hurt to build it to be rowdy! lol

What would the compression ratio be? About 7.5:1? Just throw some more boost to it! I know there are a bunch of "Vitara" pistons out there. Is there a certain one people are using?

I apologize for the questions. I will look it over as soon as I get to the house if you guys dont beat me to it.
 
#17 · (Edited)
#20 · (Edited)
ok...

I actually got to sit down at my desk and go over some stuff on a full size monitor.

Using that calculator and looking at the numbers and reading a few other posts on here I am going to do the following:

CX Racing Rods
Clevite Main Bearings, Rod Bearings, and Thrust washers
ARP Rod Bolts
ARP Girdle Bolts
ARP Head Bolts
Ebay special PM3 YCP Pistons and NPR Rings
Supertech Springs and retainers
Delta Regrind Cam

Of course all the other rebuild goodies such as seals and gaskets. Along with a full head rebuild with new valve guides and seals from Supertech.

Now to the turbo... I was going to go with a GT2871R but that might not do it.

Also, there is no telling how much boost those PM3 pistons can hold...

Any suggestions about a turbo?

Edit: I am scratching the Valve Springs and retainers along with the aftermarket cam. I read the post on the A6 cam and the B7 cam. I am going to go with the 88' A6 cam and according to the post i already A6 valve springs and retainers because my motor is a 94 d15b7! lol
 
#21 ·
I told you........

Like I said, keep. Low goal and just do a conservative stock block setup tuned to 180-200. I've been crunching the numbers and speaking to engine builders since 2009 about this very subject. The only reason the build in my sig would be okay is because of the cr........but that's really it. I wanted to be different.