Basic Turbo Setup - Will result be OK and am I forgetting an

[Mooro]

So I would love to get my hands on a NA MX5 in either turbo/SC form or do the conversion myself.

I'm on a fairly tight budget, but my power goals aren't huge but I would like it to be reliable...

Now lets assume I manage to pick up an NA8 Clubman at a good price...strong LSD diff is a great bonus along with the bigger brakes. I already have some nice 16x7 +32 Enkei RP01's and about $1000 set aside to try and get some 2nd hand coilovers or Koni/Eiback setup. So the next focus would be a basic turbo setup with the aim of getting close to 200rwhp reliably and still maintaining acceptable driveability and fuel economy.

What I'm thinking is
RB20/RB25 turbo = cheap, responsive and good size but may cause difficulty with finding a manifold to suit. Other option for a bit more money is a T28 from S14/S15 silvia.

One of those cheap SS log manifolds off ebay

Water-Air intercooler setup from GT4 celica or Subaru Liberty...will settle for Air/Air if necessary but would like to try Water/Air for improved throttle response.

Oil/Water lines for turbo

Injectors from the turbo BP motor - is this necessary for 200rwhp?

AFM from turbo BP motor - is this necessary for 200rwhp?

I'm wondering about getting one of those cheap Chinese dump front pipes to from the nissan equivalent (RB20/RB25 or Silvia) to suit the turbo and then get it cut and shut to fit the MX5...might be a bad idea and maybe should just get one to suit MX5 if available?

A basic 2.5 - 3\" exhaust to suit

Basic heavy duty clutch upgrade - is this absolutely necessary straight away?

2nd hand Greddy Emange Blue to run it all with the stock ecu + dyno time...firstly will this work and secondly will the result be a pig to drive which drinks petrol or is it possible to get a nice result with some time on the dyno?


So I'm looking for any feedback on the above...what have I missed? What won't work? What would be better/cheaper?

[Fatty]

send a PM to black & tan i think he still has an rb20 turbo and 1.8 turbo manifold for sale. but yes i think you will need to get an adaptor plate made up to mate these 2 items together, no big deal at all. a few forum members have gone this way with good results.

i think you will need to upgrade the injectors, yes.

you should not need a different afm (actually on a 1.8 it's a maf i think , not an afm) the standard one will be fine.

a 2.5\" system is plenty big enough, no need to go to 3\".

i know nothing about water/air intercoolers. air/air is easy to do, just get a cheap ebay intercooler from justjap for example. but yeah water/air is an interesting option to investigate, i'd like to see how you go with that.

as far as dump pipes go i think you will struggle finding anything suitable, best bet is to get a custom one fabbed up at a good local exhaust shop.

standard 1.8 clutch should be fine i think ? ?

greddy emanage i think a few of the guys here are using those succesfully. even cheaper again is the jaycar dfa , after a dyno tune my car runs nicely on this, it is no pig to drive and not too thirsty.

finally, as others will no doubt mention, spend some time going back thru the pages of this sub-forum. this topic has come up numerous times and it has been done to death already. also use the google search function at the bottom of the page to search this forum.

[Mooro]

Thanks for the response

I have looked through previous topics etc...I just want to get some feedback on the particular setup as a package.

I'll read up about the DFA but I like the ability to control ignition timing as well, especially when adding a turbo, which I don't think the Jaycar item can do. But if you can get a result you are happy with then that gives me hope that an Emanage will be even better.

[Mooro]

I should add that I'm hoping to run a max of 12psi on the stock motor to achieve that power which I think will go close...maybe better to get the larger RB25 turbo and run less bosst.

[Fatty]

you're right the dfa doesn't do timing, but there is a jaycar box for timing that runs off the same hand controller for the dfa. i haven't seen one in action or know anyone who has used it succesfully yet - altho there was a guy here breifly who had it fitted to an mx5. he didn't post much tho.

but then you have several different boxes rather than one, i guess it could get messy and it mught be simpler to use the emanage. but you asked for cheaper options so thought i'd mention it.

i think boags and uncle arthur used emanage and maybe a few other people.

[Mooro]

I might have a look into the Jaycar stuff...I must admit I have always been a bit of a sceptic when it comes to Jaycar but they are cheap and you are right I did ask for cheap

[Fatty]

yes they are cheap but there are several of us on this forum who have used them with good results, either turbo or naturally aspirated. whether they are good fro 200 hp i dunno coz i'm not there yet.

[Fatty]

actually as far as jaycar vs emanage it would be interesting to hear boag's thoughts as he has dríven my car so he could provide a comparison of driveability compared to his emanage system.

[Sheck]

Pretty sure you can get 200rwhp with only the 330cc GTX injectors, i'm at 189hp (@9psi) with plenty of room, i have std pressure regulator but i do have a bigger pump, walbro 255lt/m i think.

eManage will do it, make sure if you want to try the jaycar stuff that you have a tuner willing to try and tune it.
Exhaust will need to be custom if you want to go with the RB20 turbo, i'd stay away from the 25 as they have a plastic front with a ceramic back and they aren't recomended to go past 10psi (that's the s2 R33, s1 not sure and hard to find turbo).

These engines can handle alot of boost as many ppl on this forum and those overseas have done, all you need is a good tune not a diy tune (unless you tune cars for a living).

Dont those ebay manifolds have a T3 flange? that'd be perfect for the RB20 turbo, and because they are cheap who cares if they will crack in a couple of yrs time, even a year of good power production is good that those cheap prices.

2.5\" is ok, just make sure you use a good metal cat ie high flow not the crappy ceramic hi flow ones. And try to keep it as straight as possible. I used an R32 dump/front pipe, then cut the hell out of it and made it fit my car. They are a 3 inch system so i have a 3inch dump turning into a 2.5inch system just before the cat.

At 200hp i doubt a stock clutch will hold up, but i dont drive like a granny so my experience is a little lacking (i had a HD organice 1.6 clutch while running only about 130-145hp and it started to slip)

I think the GTX's still ran an AFM, but you may as well get an RX7 ser 4/5 turbo version as they are pretty cheap and do the job well, though it will probably limit your power and lower the response.

Try one of the US forums for more tips, turbomiata or something like that.
Dave

[stevesports]

dont' forget that doubling the power and possibly more to torque will stress your driveline and gearbox. I've mentioned this in the clutch thread but adding an aggressive clutch will inevitably put the stress on the gearbox, so i would recommend a HD full face clutch to prolong the life of the box. Also, the diff as well and others.

don't forget to upgrade the brakes, of which i think is more important than POWAHHH!!!!

[Mooro]

Thanks for all the responses so far.

I think Shecks car is a good example of what I want to achieve...whilst a AVO kit would be nice, unless something decent pops up second-hand it probably wont fit in the budget...There was that 1.8L turbo kit for sale a while (Blue94T??) came with engine, box, radiator, intercooler, ecu everything, thatr would have been perfect.

Going back to Shecks car, I'm sure he possibly spent a fair amount in end going through the trial and error process etc, but if you actually sum up the component cost of his basic setup (ie ignore, 6 speed, diff etc) then I don't think it would be much at 2nd hand prices.

I guess the other thing to consider is getting it legally registered. I will be moving to Tassie soon, I'm not sure of the laws their but I'm presuming I would need to get it all engineered as well which could be costly.

[Sheck]

i think the 1.8 brakes are overrated, my bro upgraded to them with some good pads and they felt sh*t, i've had no troubles as of yet with the 1.6 std brakes, and yes i have tracked them not only drifted them. I would probably go bigger if i was to track the car regularly but i would skip the 1.8 and go for either the biggest 1.8 set or a custom 4 pot setup.

The NA8 Mooro is looking at will have the diff already, just the gearbox will need upgrading once he breaks the 5 speed

Dave

[Mooro]

Exhaust will need to be custom if you want to go with the RB20 turbo, i'd stay away from the 25 as they have a plastic front with a ceramic back and they aren't recomended to go past 10psi (that's the s2 R33, s1 not sure and hard to find turbo).

I've heard that as well...but the general rule of thumb seems to be that 10psi is the recommended max boost on a RB25 - a 2.5L engine. The way I look at it (and I maybe wrong), to achieve 10psi on a 1.8L engine the turbo will need to pump less air, and hence spin slower so they should be safe for a bit more boost on a smaller engine. A lot of the RB20 guys use them and run 12psi+ without too many dramas...that said an RB20 turbo will possibly get me to the 200rwhp mark and also be a little more responsive, might be generating a bit more heat though?