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Infedora
07-13-2018, 10:07 AM
Every time I post a question about 1.6 mods I feel like I'm trolling you guys, but I am serious (but perhaps not sensible ;)

Any measurable returns with a standalone ecu? Other than finding a dusty pair on somebody's used parts pile is there any manufacturers that have a reasonable price?

Open to suggestions other than swap in a 1.8.

DarylSibcy
07-13-2018, 11:02 AM
A stand-alone ECU will net you power across the board, probably by the biggest margain - tech has moved forward.

Cams aren’t cheap for a reason, if they are they’re crap...

Generally from what I’ve seen 256 is about as high as you should go if you don’t want to kill your torque figures. Running Piper Cams myself, roughly 238 intake / 256 exhaust. They provide solid power, but the intake could be beefed up a tad.

The only major issues you’ll have are with the tuning, and the valve train - if you get a really hot cam (say 256/264), you’ll have to start looking at the valves, shims and updated lifters. It’s not cheap work

Infedora
07-13-2018, 11:08 AM
Certainly not sensible. I'm beginning to think its time to revisit the UK with a big suitcase. Seems there is more for me to find there. Wonder if anyone is selling there 1.6 ITB's?

DarylSibcy
07-13-2018, 12:53 PM
Certainly not sensible. I'm beginning to think its time to revisit the UK with a big suitcase. Seems there is more for me to find there. Wonder if anyone is selling there 1.6 ITB's?

If you do either hook up with BlinkMotorsport, or Skuzzle Motorsprt, they can help with anything Miata related

kung fu jesus
07-14-2018, 08:04 PM
256 cams are pretty mild. What is the lift?

Infedora
07-14-2018, 10:17 PM
Around 8.6mm or more. This would be installed in a freshly rebuilt head with .030 to .040 skim.

DarylSibcy
07-15-2018, 05:21 AM
256 cams are pretty mild. What is the lift?

I’ve always thought 256 was pretty hot :shrug: I could be wrong though, KFJ knows a lot more than I do so I’d listen to him :lol:

I know of people who have run 264/264 10mm Cams, but had to spend a lot of time and money getting the tune right for a good idle.

The highest I’ve seen reliably was an RS Aizawa 1.8. 272/264, really good overlap and a solid idle, very driveable from the few videos of seen - my speculations are purely from the sound on a YouTube video though, don’t see it as credible advice :lol: I’m an amateur at the end of the day :D

I imagine that RS Aizawa spent hours upon hours getting their tune spot on to be that reliable though. Their 1.8 was good for about 200hp, I think at the crank.. :shrug:

kung fu jesus
07-15-2018, 03:13 PM
Most people who run cams won’t divulge specs, there is a LOT of tuning mechanically and electronically to get them dialed in.

RoT, the stock ECU can handle 256 duration, but you may need an AFPR. 264 is streetable with a stand-alone ECU and tuning. 272+ is where things get ‘unstreetable’ in the common meaning.

Lift is where you need to be careful. I don’t recall the binding max of the stock springs, but 8-8.2mm rings a bell. Beyond that you need different springs to handle additional lift.

Springs are also tricky, too stiff and you rob power, too light and you float the valves. All this info is out there on internet and in the tech/service manuals.

There were people using springs from other cars, but I won’t tell you which ones because I don’t know your application.

Adjustable cam gears are also a must and you should expect to spend a number of hours fine tuning spark and fuel on top of overlap. Cams are not exactly a bolt-on-and-go addition.

Greasemonkey2000
07-15-2018, 10:09 PM
While the stock ecu can handle said cams it is important to take note of this:

**If high flow intake and exhaust are both used with any of the cams on this page, the OEM ECU will not provide enough fuel potentially leading a a dangerously lean condition (boom!). Additional power gains will be found with a fully programmable ECU regardless of what other parts are fitted to the engine.
Per SuperMiata: https://supermiata.com/Tomei-miata-cam.aspx

Steven aka KFJ more or less stated this, just a little differently. :D

Infedora
07-15-2018, 10:31 PM
I'll be running standalone soon, if only to maximize what I have and begin the tuning learning process. Definitely want to stay away from the boom condition, but of course if that happens,yeah, 1.8 swap. My 1.6 is a test bed for me to learn on, and frankly I like the engine. It's like me, underpowered, but giving it all I got.

kung fu jesus
07-16-2018, 08:45 PM
Gotta say, for the price of doing cams correctly on a B6, you can swap a bp4 or bp5 and make the same or more power with room to make more, and easier.

Infedora
07-16-2018, 09:14 PM
:roll:

DarylSibcy
07-17-2018, 06:47 AM
Currently consulting a few experts on the matter on Cam specs, namely HarryB :winky:

You could look at different duration cams for intake and exhaust, as long as the lift is the same you shouldn't have any issues.

As I say, RS Aiwaza run 272/264 in/ex

kung fu jesus
07-17-2018, 07:26 AM
:roll:

For those considering cams, here's a fair breakdown:

b6ze cam project:
Cams...500-1000
Cam gears... 200
Valve spring kit...400
Head work (shave+tank)...50-200
HG+seals...150
ECU dyno tuning...300-750
Injectors...100-300
Wideband O2...$200-300
ECU...800-1000
$2700-4200

(optional)
Valve seats + guides ...200-400
Valves...160-350
Studs...100

$460-750

BP4W/BP5D (good numbers, average mileage)

Engine...1000-1300/800-1200
clutch+flywheel...500-700
Swap kit...150-400

$1650-2400/1450-2200

(optional)
LSD conversion...600-900
VVT tuner...210
WBO2...200-300
ECU...800-1000
Dyno tuning...150-500

Infedora
07-17-2018, 10:33 AM
Good points KFJ, I'm going to save the money for a full bolt on JDM ground effects and custom bumper package. That should significantly reduce drag and give me better acceleration at a much better price :P

kung fu jesus
07-17-2018, 05:16 PM
It’s your money, do as you wish. ;)