rods only
 

So, I don't want a crazy 350hp miata. I want a moderate maybe 250hp. If I just throw forged rods in, would I be alright? Pistons should be good for that right? I have the motor out of the car right now awaiting full seal/gasket replacement as well as a happy meal clutch. Also going to (I know I know) finally drill and tap the oil pan for the oil drain.

The car is a 1.6 with a greddy kit. It has 550cc injectors, MS3x, mbc, no a/c and no heat (po cut the brass fittings). I am in the process of getting an open 1.8 diff/axles/driveshaft while the motor is out. Eventually the car will be turning into an exocet (think 6 months maybe longer).

So are forged rods only good enough to not grenade the motor? Or should I do pistons as well? Thanks.

I wouldn't waste money building a 1.6, unless you have a really good reason to
Otherwise yes it should work for your needs

Awesome, thank you. I should really be OK without rods as long as I can control the torque at lower rpms. But I think I would rather throw them in anyway.

If someone doesn't mind, can you check these fittings and make sure I have what I need to do my oil drain?

Turbo Oil Drain Flange 8AN Mitsubishi TD04 TD05 TD06 | eBay

8 An Male Flare to 3 8" NPT Pipe Thread Blue Pre 60886 | eBay

Pre 10890 8 An 90 Degree Swivel Hose End Fitting for Braided Hose Red Blue | eBay

Pre 10800 8 An Straight Swivel Hose End Fitting Braid Anodized Aluminium | eBay

I think that is all I need, minus the hose.

Unless you plan to show off those fitting, stay away. They're more trouble than needed. Plus the super cheap eBay ones are super cheap and will leak at the swivel.

Get some name brand fitting and be done.

For example: Brass Push Lock Hose Fittings | Dallas, Fort Worth, Cleburne, Pleasanton, Midland, Texas | 4-STAR Hose

Push lock style is great for oil drain and cheep too

So if I want to do it the AN way would summit racing be a good place to buy them?

Yes. Summit and Jegs will have what you need. Even their house brand parts are better than eBay.

Not going to make a new thread for this. But quick question.

I drilled the pan out to 9/16, and tapped to 3/8 npt. Threaded the tap almost all the way through, only left 2 threads left on the end. Man there were a lot of metal shavings. Glad I have the pan off! I tapped it here because the car doesn't have A/C, so the bracket is not there. I used JB weld on the threads, threaded it though and left 2 threads left on it to cover with the JB weld. Does this look like it will hold up fine?

Attachment 233447

looks good to me. definitely one of the cleaner ones I've seen.

But if I had the pan off I'd take it to a welder for some piece of mind but that should hold up just fine.

I'm pretty sure it will hold up fine as well, just wanted to get another opinion.

1.6 coolant reroute question. I know all you have to do is swap the front housing with the rear, but what do you do with the heater core line up front? It interferes with the timing belt area. Just cut it off and put a plug or weld it shut?

Also, for the rear, since I don't have a heater core, is there enough space to put the thermoswitch in like it sits? Or do I need to cap that off, drill and tap on the side?

Attachment 233445

Attachment 233446

Thanks for the help!

there are a ton of write ups on the coolant reroute topic. Try searching: revlimiter coolant reroute.
Also why do a 1.8 open diff? look for a torsen lsd equip'ed rear, or you'll just be spinning all over the place.

Wrong, wrong, so much wrong.

Rear neck needs to be on a spacer*, so you can thread in the sensor that's currently sitting on the front of your engine, and to fit a hose barb to feed the heater core. Once this spacer is in place, the old front water neck will need to be milled down and welded shut, or it'll hit the firewall.

Front neck needs** to have a plate bolted on, we never reuse the rear neck. This plate needs to be drilled and tapped for the fan switch***, which is currently sitting on the back of your engine.

*unless you drill and tap the head for these sensors.

**unless you remove and replace with a freeze plug behind the timing belt.

***unless you have an aftermarket ECU controlling the fan off the ECU's coolant sensor.

rods for 250hp? why?


edit: just read thread. wow.

You're doing a lot of work for 250whp

Breaking things apart and modifying stuff...I'm surprised you have the self control to beat the 'might as well' bug. I started off with a 1.6 build and have now ended up with a built 1.8.

Similar amount of effort, might as well...

Yeah after posting those pictures I realized I have one of skou's spacers sitting on my desk. I will use that in the rear. Hose barb for the heater hose going to the mixing manifold. Stock ecu sensor in there as well. I have a ms3x, so I can run the fan from that. Ordered the freeze plug kit from trackspeed and the Kia water neck from begi.

Other than that, I just want to get rid of the stock differential for now. Later on down the road I can swap to the torsen if I feel I need to. Also touching on the "rods for 250whp" subject. I will probably throw pistons in as well to give me the upgrade path if I ever want to go with a bigger turbo. My goal for now is just there at the breaking point for stock rods so I don't want to do this work then bend a rod and have to pull the motor again.

If your car is eventually going to be a doner for an exocet, looks like you're pulling the motor for the most part anyway (unless you simply lift the shell).

Why not just keep your car running the way it is; and build a spare 1.8 motor with the tits and whistles for the exocet. Might as well.

I plan on pulling the body off when I get to that point.

I've just decided to keep with the 1.6. I know the 1.8 is better but I'm sticking with it. I'm not looking for monster power and my goals are within reach on a 1.6.

It'll be plenty awesome for an exocet anyways.

For the rear housing bolts, I need a 70mm bolt for the longer side, and what for the shorter side? I grabbed a 60mm (all lowes had) and it's too long for the short side and too short for the long side. Probably a 70mm and a 50mm?