Building a 99-00 1.8L for Realiablility goals on a SC system.
 

Alright this build is not one where I expect many to say "Thats a radical build" I honestly I will be building this for a NA Miata as a test run to see what I think before I decide to go forward with my KL swap in the NB or build the 1.8 in it and sell the KL.

The goals are 300HP or so from a Eaton M62 Clutched.
Megasquirt and E85.
Full Exhaust w/Header.
Full Suspension and Torsen Diff.

Now for this to get close (Which it seems most SC builds of the past did not really get over 200 quite well but I have no run across my build idea yet. Either way again this is not a Max Power build, reliable comes first) I know were looking at optimistic but I will be working on a Custom Pulley to get the boost to a max of 15psi (We saw a max of 12 PSI with this SC on a 2.5L KL so on a 1.8L BP I would think its possible with the right crank pulley (You can not change the SC Pulley since this is a clutched version).

We are going to use a 100k 1.8L that runs and so far for the build I am wanting to do the following:
1) Forged Pistons at the stock compression ratio to help increase power output. (Another reason for MS and E85)
2) Forged Rod's to ensure strength.
3) All ARP Hardware
4) The best Head Gasket choice (Would like input here please)


Now I am looking for feedback but thats the basic idea, also I would like to hear about which pistons and rods people recommend since obviously this is not a high numbers build but we do want it to be good quality, we will be double checking everything at the shop.

As for other questions:
1) Cams, any vendor pref. here and how many grinds are there to choose from?
2) Valve Springs and Retainers, any upgrades that are a good idea to do since were going to be going through anyway? (Plan on doing a slight PnP anyway but nothing extreme like bigger valves at this time)
3) What Bearings do you guys pref when rebuilding, OEM or?
4) Base map for 1.8L and the Eaton M62?
5) Recommendations on other points that could be weak or in need of attention.
6) Do you guys shim the oil pump, upgrade it or anything sim or again is OEM fine?

I plan on doing a coolant reroute on the setup as well as better clutch obviously.

Also I was thinking about using 800-1000cc Injector Dynamics Injectors, any pref. over those or decent deals?

Thanks everyone.

You'll need a LOT more than 15psi on an MP62

A guy on mx5nutz had 270fw/up on a 2001 engine at 17psi

Big gulp was 20psi iirc to get 300 from an MP62 on a MK2 engine.

P.s. Over 200 isn't a strugge from an MP62, it's the M45 based chargers that struggle to breach it.

Well getting close is fine, I would love to see those others and compare the compression and fuel as well as management just to get an idea with mine but it seems from your post getting to close to 250 should not be a big issue.

I was shooting for 15psi as I was not sure just what to be able to expect efficiently yet for a M62 on the 1.8L BP.

However reliable is a big thing, I do not want to push it to the point we lose reliability just for a little more power, were talking a 91 shell so its going to be nice and light.

I will look for mx5nutz to see his build/setup thank you for the direction to go on that one. Same with Big Gulp.

Do cams for sure and using E85 you should run MORE compression. remember that a pulley and charger that makes 15psi on a stock engine will only make 12 psi on a cammed worked one but be flowing the same air, so you will likely need a bigger pulley again to reach 15 psi.

Dann

I was thinking that myself which was another reason I wanted to stay right around 15psi after brake in. I thought it was a safe and reliable every day amount for when I have the SC actually on.

Hopefully when I do all the ordering I can double up on a few parts and get a better deal for some extra's in my NB such as cams and injectors, etc.

aren't you going to be tapping out the compressor once you start reaching those pressure levels? I didn't think the eaton M's could benefit much in the mid-high teens. Correct me if I'm wrong, I've never owned one but feel like I got familiar helping friends with supercoupes, etc.

I was looking into cams recently and it seems that money is better off spent on intake/head flow than messing with the cams. More compression seems like a bad idea to me as well. You're just talking about tightening your window of what is a safe tune. It sounds like you're happy to give up a little hp for the sake of reliability.

I'm surprised this thread has gone 6 posts without someone saying "get a turbo". Considering the build you're looking at and the size of the injectors it would be a lot easier to just turn a little knob to get the power you want rather than buying/swapping pulleys and belts.

^^ I'm going to say it. Why not just you throw some rods in the motor and slap on a 2871? It really is that simple to get 300 whp.
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He wants Trq at the flip of a switch and at 1000 rpm, I gave him both options he choose the SC and its a fun SC.

As for being out of breath with my use of the M62 on the 2.5L KL Mazda at 12Psi I felt we had maxed its efficiency.
So for th 1.8L BP I would say 15Psi reaches that same area.

The gentleman is a little older and started with trying to get me to swap in a 5.0 into the Miata which I just did not want to do. I am much happier with this result lol.

Also added further questions, I left some out originally because I had so much going on at once now that I can sit down and look (And he messaged me he already bought a rebuilt and warrantied Eaton M62) I am going over everything.