JE 8.5:1 Pistons

[HiBoost TS]

What do these pistons come from? What is the comp. ratio?

They are factory Mazda pistons which we machine down to lower the compression ratio.

We use these on all our South America applications where the best fuel is 87 to 89 octane. About 145 sets are working perfectly on customers cars since 1999.

 

[perfworks]

i would do it just to lower the static compression ratio, thus minimizing the risk on detonation.

well said

 

[perfworks]

Lower compression is safer on turbo engines. There is less detonation and you can run more boost.

I am working on doing a set of pistons and rods using the stock "lower compression" pistons and pauter rods. I will make the slots to put the floating pins on the stock piston. This setup is much cheaper than forged pistons and you will not get the knocking sound of JEs.

Juan

jaun we have already looked into this. The stock pistons loose their integrity and dont hold up well with higher cylinder pressures. My advsie to you is to use the forged aluminum. The noise subsides when you warm then up. That is what they are designed to do. If you increase the silicon content in the pistons this will help tighten up clearances and get rid of some of the idle noise. my two cents.
Also we have the exact setup for sale also. Forged aluminum pistons and rings with pauter rods and wrist pins. You all know how to reach me if your interested

 

[perfworks]

They are factory Mazda pistons which we machine down to lower the compression ratio.

We use these on all our South America applications where the best fuel is 87 to 89 octane. About 145 sets are working perfectly on customers cars since 1999.

Jaun there are many ways to machine the piston. which way are you doing it?

 

[igdrasil]

Jaun there are many ways to machine the piston. which way are you doing it?

Yeah I want to know too.
How much could be the cost of doing that?
And how you know you machined all 4 the same, you could get different compression on each cylinder...is that bad?
what if after the work, the compression reads like:
180psi
170psi
175psi
150psi

 

[brennan]

I want to eventually get forged internals in my msp, now what would I have to buy besides forged rods and pistons, would there be anything else I should upgrade when doing so. Also who makes forged rods and pistons for the msp?

 

[igdrasil]

I want to eventually get forged internals in my msp, now what would I have to buy besides forged rods and pistons, would there be anything else I should upgrade when doing so. Also who makes forged rods and pistons for the msp?

Pistons Rings
Rod Bearings
Crank Bearings (if you take out the crankshaft) but, its is recommended to change it anyway
Gaskets

etc...

I may have not mention everything, but those are a must.

 

[HiBoost TS]

jaun we have already looked into this. The stock pistons loose their integrity and dont hold up well with higher cylinder pressures. My advsie to you is to use the forged aluminum. The noise subsides when you warm then up. That is what they are designed to do. If you increase the silicon content in the pistons this will help tighten up clearances and get rid of some of the idle noise. my two cents.
Also we have the exact setup for sale also. Forged aluminum pistons and rings with pauter rods and wrist pins. You all know how to reach me if your interested

I totally agree with you about the noise going away as the engine warms up. Also about the high silicone ones. We use the SRPs which are high in silicon to get rid of the idle noise.

However, I disagree about the piston loosing its integrity when machined down. We have run cars with machined pistons up to 22 psi without any trouble. In fact, we only use forged ones when we run turbo and Nitrous together.

The pistons are machined in a CNC to get the same compression on all 4 of them.

The stock piston will take a lot of power if the engine is well tuned.

If you get a lean mixture or detonation due to a very advance timing, not even the best forged piston will take it.

Juan

 

[igdrasil]

How much is the job for doing that CNC machining thing to the pistons?

 

[PaulMP3]

This sounds like a nice alternitive to forged pistons. 22psi is impressive.

 

[perfworks]

I totally agree with you about the noise going away as the engine warms up. Also about the high silicone ones. We use the SRPs which are high in silicon to get rid of the idle noise.

However, I disagree about the piston loosing its integrity when machined down. We have run cars with machined pistons up to 22 psi without any trouble. In fact, we only use forged ones when we run turbo and Nitrous together.

The pistons are machined in a CNC to get the same compression on all 4 of them.

The stock piston will take a lot of power if the engine is well tuned.

If you get a lean mixture or detonation due to a very advance timing, not even the best forged piston will take it.

The majority of all the 2001 + FS motors with blown engines have had problems number 1- pistons cracking number 2- rods bending and eventually snapping. The pistons i'll agree can take some abuse but not extended periods of detonation. I find that it isnt worth the time to machine nor wait for it to be machined. The pistons that come from JE/ SRP are already balanced and can handle much more than the stock pistons can. They have a tendency to crack literally around valve relief. If it is cost effective for you then good luck but the motor we did it to could NOT hanlde those cylinder pressures and temps. The aftermarket units that have a silicon content above eutectic standards also act as a barrier to heat and protect the piston at higher rpms. It is my opinion that ht eforged aluminum is the way to go

Juan

 

[HiBoost TS]

I just want to share with this community some of my experience.

I agree that if you are going to build a race proof engine, you should use the best available parts, however most of us here just want to have a reliable engine in our cars to be a daily driver and still be able run 200 WHP safely.

Running 8.5 to 1 compression ratio and the proper fuel/ignition setup will be good enough to 250 WHP on pump gas.

Juan

 

[perfworks]

I just want to share with this community some of my experience.

I agree that if you are going to build a race proof engine, you should use the best available parts, however most of us here just want to have a reliable engine in our cars to be a daily driver and still be able run 200 WHP safely.

Running 8.5 to 1 compression ratio and the proper fuel/ignition setup will be good enough to 250 WHP on pump gas.

Juan

hey not to get off topic but that is very strange what happened to my post. It combined with your quote!!
well any way i know you saw what i wrote.
Yes , i agree with you jaun, its great to have someone with experience to help.
Your above statement is correct. The majority of the people here want to run safely. But my thoughts are that if you spent the time to take the motor apart then go with the best you can get your hands on. If that means that your budget fits around getting the stock pistons machined or going with customs then thats great. As long as you do something constructive.
I am also glad that you are talking about the right engine management. Many people forget that. YOU NEED ignition control.
Your numebr of 250whp is right about on the mark for average. With some work like you say with rods and machined pistons you should be able to get close to the 300WHP level. Then its a new ball game with the tranny and axles needing some attention

 

[perfworks]

This was my original post. For some reason it got mixed up with a quote . sorry jaun


The majority of all the 2001 + FS motors with blown engines have had problems number 1- pistons cracking number 2- rods bending and eventually snapping. The pistons i'll agree can take some abuse but not extended periods of detonation. I find that it isnt worth the time to machine nor wait for it to be machined. The pistons that come from JE/ SRP are already balanced and can handle much more than the stock pistons can. They have a tendency to crack literally around valve relief. If it is cost effective for you then good luck but the motor we did it to could NOT hanlde those cylinder pressures and temps. The aftermarket units that have a silicon content above eutectic standards also act as a barrier to heat and protect the piston at higher rpms. It is my opinion that ht eforged aluminum is the way to go

 

[ddogg777]

Juan, could you state the prices now on this piston work?

 

[LinuxRacr]

I hope the pistons were machined with the reliefe cut-out for the oil squirters to clear. All my oil squirters got cut off by the pistons. :mad:

 

[HiBoost TS]

Juan, could you state the prices now on this piston work?

ddogg777,
Do you mean the stock pistons machined to a lower 8.5 :1 compression ratio or the JEs?

Linux, we know about the indentation we have to make to clear the skirters. We have installed like 5 or 6 JE kits in Mazda Capella which has the same FS engine as our Proteges.

 

[perfworks]

if you are using the stock pistons there is no need for the cut out on the skirt.

Jaun , do you need a set of pauter rods?
I have a set i am getting rid of. email or PM me if your interested.
I have a thread about it on the for sale area
I figured it would be a little cheaper for you if you had a project to do.

 

[ddogg777]

Juan, I am interested in the machining work of the stock pistons. I think I might buy Perf's rods and then get the piston machining done if it's cost effective. Otherwise I might put a bid on his pistons too.

 

[70]

This is all very interesting...


Ok ok, so I just had to post something so that I woul get the e-mail to remind me to continue reading this thread...