Advice for 1.6 Engine rebuild for street/track?

[meta]

Hi everyone,

SO...after selling my beloved NA6 early last year...i've realised simply...i screwed up lol (if you live in brisbane, you may have seen it around, it's a velocity red NA6, with racing beat front bar rolling on 17inch bbs mesh style rims...shouldn't have sold it! lol...or given away everything else with it...damn!!!)

Anyway, i posted long ago about building up an engine and ironically, i started, then my na6 short crank decided to let go...stupid wood drift key!!!!! Basically i never got to do it


So now, with another deployment this year, i figured what the hell, time for another mx5...except i'm doing it right this time!

Essentially, i wish to have built a b6 (either short or long crank) with Individual throttle bodies....I'm obsessed with that RS Aizawa Roadster lol

I have a decent budget to play around with, so money or time isn't a concern as i'll be away for 8 months lol

I'm after some honest advice on everything lol, including any reputable engine builders, mistakes you may have made in your own quest to build a naturally aspirated motor, or any other issues that may have risen?

I don't wish to build a 1800, i've considered this before and i'm not interested, as my goals aren't power, i'm happy with the response of the B6 and would like to keep things as is

So please if you have any advice, pricing for parts/ labour on such a build or any other miscellaneous thoughts, fire away, i've already started scouring the forum pages for past builds and topics, so i'm slowly getting there lol

Thanks

Meta

[PaulF]

I see you're from Newcastle. NitroDann is local and has a pretty awesome (currently) N/A B6 and has built a few engines, so he'd be worth talking to. We also meet at Mt Sugarloaf on the second Sunday of every month (which means this Sunday) if you're interested in coming along.

[meta]

Hi Paul,
I completely forgot that my status still says i'm from Newcastle, unfortunately, i now resided in Townsville, as for NitroDann, does he have a contact number? or a shop he works for? It's a pity, i hadn't met more Novacastrians when i had the NA, it would of been good to run up Sugarloaf with other mx5s

[PaulF]

Ah, fair enough. I'll get Dann to have a look at this thread.

[meta]

Thanks mate, i appreciate it

[wozzah1975]

Thanks mate, i appreciate it

How much power are you chasing? And how much money are you prepared to spend on the package?

Cheers
Woz

[meta]

Thanks mate, i appreciate it

How much power are you chasing? And how much money are you prepared to spend on the package?

Cheers
Woz

Hi Woz,

I'm actually not chasing power, hence the 1600 as opposed to 1800, I'm just after a more responsive 1600 motor with a little more torque and balance through the rev ranges, and over-all reliability

As for the package, all up including a second hand 1600 short/long block, up to $8000, I believe that's more than enough for what I want to achieve, if it goes any higher, i'll just buy the flyinn' miata long motor or something to that effect, minus the throttle bodies

In saying all of this, that's "JUST" for the motor, not including the other supporting parts

Thanks

Meta

[NitroDann]

Jesus it wont cost you that much, something like mine will cost way less.

Id use part of your budget to buy a 6 speed and 4.1 torsen.

Some 280 odd degree cams, 11:1 compression on petrol, 13:1 on E85, megasquirt, 4-2-1 extractors, stock rods and crank balanced, a bit of a port job and you have over 100rwkw.

If wozzah contradicts me in anyway, he is right.

Dann

[wozzah1975]

Jesus it wont cost you that much, something like mine will cost way less.

Id use part of your budget to buy a 6 speed and 4.1 torsen.

Some 280 odd degree cams, 11:1 compression on petrol, 13:1 on E85, megasquirt, 4-2-1 extractors, stock rods and crank balanced, a bit of a port job and you have over 100rwkw.

If wozzah contradicts me in anyway, he is right.

Dann

hehe,

I'd probably get a little more serious than that, with that budget it will give you a good result. Danns package would work well though, nice mild cams, good comp ratio and 4-2-1 headers, but on a road car I'm not sure the E85 is needed, or a practical idea for what you need.

definately factor in a diff ratio change, even if you don't do the gearbox.

As far as the engine is concerned there's a few ways on how you'd go about it.

If it were mine I would:
BOTTOM END
Spool Rods or equiv (cheap and bullet proof)
Oversize pistons (hi comp, 10-5-11:1)
(There are plenty of piston and rod packages available really well priced)
fully balance and reco the bottom end
Lighten the flywheel
TOP END
Use 290-300deg cams (depending on how you like to drive it)
Port and reco the cyl head to spec, and use bigger valves.
4-2-1 headers
As with any engine, the key to making the best power curve is all in how the engine breaths. Having a cylinder head that flows well and maintains airspeed is critical on everything you attach to it. If the cylinder head is done right, then the rest of the add ons (cams, extractors, intake) work better, the power curve is broader and the engine is more responsive.

You suggested you were going to use throttle bodies. Excellent plan, these give really good throttle response and power. Rule of thumb though, don't go too big. Taperered throttle bodies with a 40mm butterfly will be heaps, or alternatively just a 40mm set. These maintain excellent air speed for low end torque, and still give excellent mid-top power.
What were you planning to use?

Also, same with the exhaust. 4-2-1 headers with a 2 1/4" system will be more than enough. Don't over do it.

Aftermarket ECU (Dann suggested Megasquirt, I havent played with one of these yet, but I read good things).

A package like this will see 110-120kw at the wheels without much trouble at all, and be super reliable and very drivable.

Danns package will also work well, but given your budget I think we can see more power

Cheers
Woz

[NitroDann]

Lol, great minds think alike.

Wozzah you are going to give him something he cant handle lol. My build suggestion assumes a 5 grand budget for the engine/ecu/tune alone.

Dann

[wozzah1975]

Lol, great minds think alike.

Wozzah you are going to give him something he cant handle lol. My build suggestion assumes a 5 grand budget for the engine/ecu/tune alone.

Dann

He said $8K for the engine alone, less the hang ons

ECU's and tuning are hang ons.....lol

I'm happy to spend his money!!! hehe

Woz

[Si.G]

It is a shame my motor is not running yet to give you an idea of results, but here is my build

http://mx5cartalk.com/forum/viewtopic.php?f=57&t=40374&start=150

Pretty much in line with what Dann recommends -

There are places you can save money over my build, for example, if you are not chasing high rpm, you can do without the billet oil pump and valve springs, also cheaper pistons and rods are available too.

I run a megasquirt pnp - runs very well and I have had no issue with it.

With regards to ITBs, I don't think you will get a cheaper set up then running Toyota AE101 bodies on the technotoy manifold. The manifold is a nice bit of kit, CNC'd, only down side I have found is that the threaded holes for the throttle bodies are not dowelled, but that is easy to fix. Also with the toyota ITBs wiring in the TPS to the Mx5 wiring loom is straight forward.

This is the spec
Engine - $300
pistons - $883 (wiseco 11:1 ceramic coated)
Rods - $962 (carrilo A beam)
Oil Pump - $600 (billet gears - needed for high rpm)
Valves/springs/retainers/head gasket - $1300 (approx not got invoice yet) (Supertech - rated to 9000rpm - apparently)
Flywheel / Clutch - $460
Machine Shop - $1500 (approx, not got final head bill)
Injectors - $64 (Recon Supra Injector from ebay)
COPs - $155 (Toyota Corrola)
Gasket Set - $140 (from UK)
Intake Manifold - $240 (technotoy tuning)
Harmonic Balancer - $300 (ATI)
Studs - $220 (ARP Crank and head)
Bearings - $150 (ACL race bearings)

[timk]

Is this Minh's Velocity Red NA? If not, there are at least two Velocity Red NAs getting around now!

It's a pretty cool colour for the NA!

[wozzah1975]

Jesus it wont cost you that much, something like mine will cost way less.

Id use part of your budget to buy a 6 speed and 4.1 torsen.

Some 280 odd degree cams, 11:1 compression on petrol, 13:1 on E85, megasquirt, 4-2-1 extractors, stock rods and crank balanced, a bit of a port job and you have over 100rwkw.

If wozzah contradicts me in anyway, he is right.

Dann

hehe,

I'd probably get a little more serious than that, with that budget it will give you a good result. Danns package would work well though, nice mild cams, good comp ratio and 4-2-1 headers, but on a road car I'm not sure the E85 is needed, or a practical idea for what you need.

definately factor in a diff ratio change, even if you don't do the gearbox.

As far as the engine is concerned there's a few ways on how you'd go about it.

If it were mine I would:
BOTTOM END
Spool Rods or equiv (cheap and bullet proof)
Oversize pistons (hi comp, 10-5-11:1)
(There are plenty of piston and rod packages available really well priced)
fully balance and reco the bottom end
Lighten the flywheel
TOP END
Use 290-300deg cams (depending on how you like to drive it)
Port and reco the cyl head to spec, and use bigger valves.
4-2-1 headers
As with any engine, the key to making the best power curve is all in how the engine breaths. Having a cylinder head that flows well and maintains airspeed is critical on everything you attach to it. If the cylinder head is done right, then the rest of the add ons (cams, extractors, intake) work better, the power curve is broader and the engine is more responsive.

You suggested you were going to use throttle bodies. Excellent plan, these give really good throttle response and power. Rule of thumb though, don't go too big. Taperered throttle bodies with a 40mm butterfly will be heaps, or alternatively just a 40mm set. These maintain excellent air speed for low end torque, and still give excellent mid-top power.
What were you planning to use?

Also, same with the exhaust. 4-2-1 headers with a 2 1/4" system will be more than enough. Don't over do it.

Aftermarket ECU (Dann suggested Megasquirt, I havent played with one of these yet, but I read good things).

A package like this will see 110-120kw at the wheels without much trouble at all, and be super reliable and very drivable.

Danns package will also work well, but given your budget I think we can see more power

Cheers
Woz

Ok, bit of a break down as to what you can get and at what price. I prefer to buy my stuff in Aus, so have a shop around and see how much difference there is in price. It will give you an idea of what is available though. Some of my customers source this stuff themselves on my recommendation, others just let me get what I need

CONRODS & PISTONS
http://www.ebay.com.au/itm/Eagle-H-Beam ... 3f0c3df253

http://www.spoolimports.com/spool-conro ... 18-conrods

Either of these are basically bullet proof. A little heavy, but for your application fine.

http://www.ebay.com.au/itm/Eagle-Rods-W ... 3a6ac31a37

Alot of these sellers do packages on pistons and rods (please note some of the links I sent are turbo pistons, but they have other high comp items available)

VALVES/VALVE TRAIN
http://www.ebay.com.au/itm/Supertech-Va ... 3ca6d9faa0

http://www.ebay.com.au/itm/Supertech-Va ... 3a51efa511

CAMS
I don't like alot of the off the shelf profiles available for these engines. Alot of people try to "reinvent the wheel" in this area, and there is alot better profiles available.
The billet cams I use are around the $800pr mark regardless of spec.

CYL HEAD
One of my head packages is usually around the $800-1000 mark (DYO basis), ported and fully reco'd.

BLOCK AND MACHINING
The rotating assembly needs to be balanced, and the machining needs to be right. Don't go spending thousands of dollars, but get a reasonable job done, and use good quality bearings (ACL race), gaskets (MLS head gasket), seals etc, and ARP Main studs and head studs. Get the flywheel lightened also.

In respect to oil pump, in my experience the issue with the oil pump is rectified by using a Peterson external oil pressure regulator. I am yet to have even a standard pump fail when using these regulators. You should be able to pick one of these up for $150-200 (maybe cheaper now with the AUS dollar).

I wouldn't waste my money on COP's unless your ignition system is faulty. Not enough "bang for back", nor would I waste it on a fancy harmonic balancer for the same reason. I run and alloy pulley on mine, and thats it.

Where I would put some money into is with you throttle bodies. Get decent tapered ones if your budget allows it. If not, there are really good motorbike throttle bodies floating around, when adapted work very well. I have fabbed manifolds for t/bodies for about the $3-400 mark to take weber pattern, or others.

Also, spend money on a decent extractor set, 4-2-1. On this application, depending on what cams you go for I would use a custom made set which will set you back $800-1000, or just a set that are proven performers.


There is loads of stuff available, just spend it in the right areas

Woz