Curently have 270bhp, what parts are required for circa 350bhp?
 

Hi, I have a 94' 1.8 runing 270bhp (at fly) and im looking to increase the power to circa 350bhp (at fly)

My current specs are:

94' 1.8 engine with stock internals and light weight flywheel
GT2860RS on a begi tubular manifold
Seperated gas downpipe
decat and 3inch exhaust downpipe back
550 Injectors
Emerald K3 Ecu
Begi large intercooler

The car is currently producing 270 bhp @15psi

What would I need for 350?
I was thinking Carrilo A beams and weisco pistons of some flavour but other than that im unsure what else other than more PSI and lost of dyno/road tuning.

Will 550's cope?
Is the GT2860rs man enough?
Should I get a VVT head?

Basicaly im after the easiest route to 350bhp, Yeah I may be an annoying noob but mx5/Miata tuning is no where near as big here in England so there is less places to seek advice.

Any help would be much appreciated :)

I'm guessing 99 head as well. I'm running 650cc Deatschwerks. You might want more injector and at least a 225lph Walbro fuel pump. Not sure about what fuel rail.

How did you come to the 270bhp figure? did you took the motor out and dyno it that way, or you are just guesstimating?

Anyway from now talk about whp, please. For your goal which I assume will be around the ~330 whp I say your need a forged bottom end. Rule of thumb has been that rods are good for ~250whp and pistons ~300whp.

From there the head and intake manifold will restrict flow. Therefore upgrade to a 99-00 head. If you have the money to upgrade engine management then go with the VVT head. (look up the pros/cons) As for the IM is concerned simply take the Skunk manifold for Hondas and weld it to you flange-this has also been extensively covered in the forum. Then turn the boost up and profit.

270 was on sumo power's engine dyno, I have since moved further north and are unable to use them to build my engine.
For the rods will carrilo A beams suffice? I'm pretty certain the emerald ecu will do vvt so why suggest an ecu upgrade? Will the 550's be ok for 330whp?

Basicaly forge it slap on a vvt head and up boost yeah? I have around £2500 to spend which is very roughly $3800 to forge and other upgrades to my engine. Bare in mind we have to pay import tax if parts are ordered from over seas :)

The upgrade ECU is to control the retard and advance of the VVT and squeeze more power. This involves more tuning and some experimenting. I dont know know what the Emerald ECU so you might want to brief us on that; is it a fully programmable ECU? Standalone? ect...

As for the injectors, Ive seen a ~300whp, mustang dyno which should be at around you power goal, handle good with the 550 but there's little headroom at that power level. You can use the M-tune rods. They cost about ~$320 and are good for your power level.

Bottom line.

Forget bottom end
Intake manifold
Head
Tune and turn the boost up

The emerald k3 is a fully programeable standalone which can control vvt, boost, ignition, injection etc... Every thing including 3 on the fly switchable maps via incar switch, which is pretty useful.

Headroom is not too much of an issue as I doubt I will want to go much higher, but I suppose there is no such thing as enough power eh?

Was that forget or forge bottom end?

Thanks for your input guys :)

id say a big +1 on bigger injectors, you may not need the head room but the option of having more than enough fuel flow is never a bad thing. id rather have it and not need it than need it and not have it....just like condoms and guns.

I will probably go for slightly bigger injectors anyway for the reason you stated, rather be looking at it than for it.

"just like condoms and guns" made me lol! We are alowed to stock up on condoms in England but guns are another matter lol

You'll need a GT2871R if you wanna reach 350bhp.

You will need bigger injectors. 550's are good for 300 whp give or take a few.
You will need at least a 2871.
You will need a built motor.
You will need to eventually find a 6 speed.

I know nothing about your ecu so I'll let someone else chime in.
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a torsen would be a good idea as well....

I think the European MX-5s have a torsen.

To the OP; I'm surprised that you're running at 15psi with no issues.

If I were you, I'd build the motor. It won't get you to your goal but it will prevent you from blowing the engine.

Do you have access to a Begi Intake Manifold?

And Phil; he's been talking about hp at the flywheel so; if he wants to reach 350hp that would be around 280 or 290 whp. He can reach that number with his current setup and the intake Manifold.

Paul's car has 297whp and he uses a 2860rs if I'm not mistaken. Phil said the Begi Intake Mani was worth around 20whp.

The only things you NEED to change are injectors, the turbo, and the intake manifold. ID1000s, a 2871R, and a Skunk2/Blox/Edelbrock Honda IM. You'll make the power and blow the stock motor up pretty quickly afterwards. Once you do that, you'll want a bottom end like mine or Hustler's - Supertech low-comp slugs, M-Tuned rods, BE OPGs, stock head.

Your setup with a Honda IM, 2871R and 1000cc injectors will hit your power goals at 16-18psi depending on dyno and available fuel.

If you want me to put together a package to simplify it a bit, send me a PM.

^This.

My 750's were close to 80% so I would prolly go with atleast that size if you want over 300whp.

2871 will do it and you wont have to change your manifold, but I would have went with something larger myself.

Need internals, I would just go with whatever rods are on sale (how many cheap one have you seen break?) and some wiseco's.

You'll be breaking 5 speeds like no tomorrow over 300 so plan on swapping the 6 speed in soon after (well depending how you drive lol).

This stuff plus, coolant reroute, COP's, a new intake manifold, ect is all pretty standard.

EDIT: and how could I have forgotten lol Oil pump gears to prevent turning your built motor into something that looks like mine now lol

Morning (well not for you guys I expect) I for got to add I do have a 6speed and torsen on the car already, savington I will pm you later today.

I have had no issues thus @15psi appart from a cracked begi manifold and studs loosening which seems the norm, I know it is only Is matter of time though. I'm not sure about how our octane ratings differ from yours but our "premium" is 99 octaine.

different states have different ratings. here is GA is 93...

BTW everytime i see your screen name i think about Shawn of the Dead.

OP, do it.

+1 if Sav offers you a package deal, jump on it. sav is the man!

Speaking of intake manifold I just finished one for a 99 head, so...

Its not every day that Savington offers up his package. They way I go from 270-300 wheels is very annoying, it involves hooking up a boost controller. It gets in the way of me flossing and balling out of control.

Upgrade to MS3 and the closed loop EBC will work amazingly. Makes it so easy to change boost levels. Once you have dialed in the PID numbers all you have to do is go in and change what you want your target KPA to be and it hits it and holds.

Some of them have limited slip differentials
http://en.wikipedia.org/wiki/Mazda_MX-5
I think most European MX-5s have an open differential

In the USA we use AKI octane rating which is dervied from (RON+MON)\2. Alot of other Nations only use the RON rating for gasoline. You can see where people can get confused by this. So if they are running 99 octane, I believe UK runs by ron ratings, that would mean 99 octane in the UK is nearly same as 93 AKI octane in the US

He would have to run a lot of boost to get there, 20+ psi. I would rather get a 2871, he wouldn't lose any spool and he could run less boost.
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I would just stick some injectors in it, id 1000ccs and a fuel pump then try to sorce some e85 u can prolly hit your power goals with e85 on a stock motor for a lil while, forge the bottom end with like 8:1s or so and keep your small turbo. If you cant get e85 i would stick a 3071 on there so u can run around on 14psi still making your goals on normal pump gas.

A 3071 is major over kill for his goals.
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How exactly does E85 change the strength of the stock rods and allow them to withstand higher cylinder pressures...ergo force?

Well, he's right.

The engine would last... for a little while.