Zetec Piston Question

[saqmaster]

Hi folks,

Not really an SVT/ST170 question, but still Zetec.

Does anyone know the standard compression height of a stock 2 litre zetec piston? I'm talking about the 'black top' engine that's used in say a ~2000 Focus. Can you also confirm that the stock rods are 5.483" long.

Also, do you know what the deck protrusion is of the stock piston, if any?

Answers to these questions will help me design my ~12.5:1 CR pistons to run in my UK 'silver top' engine, running US length Eagle rods with a ST170/SVT head

If this is not a suitable forum, if you could point me anywhere i'd appreciate it.

Many thanks,
Stu

 

[UTlapso]

I would try focusfanatics. In my opinion your not really designing your dreaming of throwing together alot of focus parts and thinking they will work well together. I am not saying you don't know what you are doing but if you are about to lay down alot of money on your motor I would talk to some one experienced. Not to be rude

 

[HTPerformance]

12.5:1 Pistons are already available. You can also use stock pistons and go with a thinner head gasket and mill down the head/block mounting surfaces to achieve that as well.

www.Focus-Power.com or check out C-F-M.com

 

[saqmaster]

I would try focusfanatics. In my opinion your not really designing your dreaming of throwing together alot of focus parts and thinking they will work well together. I am not saying you don't know what you are doing but if you are about to lay down alot of money on your motor I would talk to some one experienced. Not to be rude

Well frankly I do take offense at your wildly-inaccurate assumption. What are you, a baker, butcher or candlestick maker? Are you a professional engineer that can make judgement?

For the record, we currently hold the record in the UK for the fastest Focus, topping out at 182.2 mph so i'd say I/we have a clue what we're doing. I'm just trying to find some information out on the US spec Zetec engine, which obviously we don't have here.

But thanks for your mainly ignorant comments. I'll check out focusfanatics. Many thanks.

 

[saqmaster]

12.5:1 Pistons are already available. You can also use stock pistons and go with a thinner head gasket and mill down the head/block mounting surfaces to achieve that as well.

www.Focus-Power.com or check out C-F-M.com

Thanks. The only off-the-shelf 12.5:1 piston i've found is sold by Nippon Power and is made by CP Pistons. I've tried to get in touch with Nippon, without success. Also CP don't know which custom drawing in their collection is for the Nippon spec pistons, so they're at a bit of a loss. The main issue is practically every single aftermarket piston is only .007" oversize, which is absolutely rediculous. Anyone who knows what they're doing when building an engine knows that you really want a virgin bore with perfectly-parallel honing, not just a quick skim through with the honing tool. It's all very well and good if you are always using a brand new block (which isn't ideal anyway!).

The block deck and head face will no doubt be machined anyway to get the optimal piston to valve clearance. The 12.5:1 CR is just a starting point really and the engine will most likely end up over 240bhp. And then there's the 100 shot or so of nitrous. For these reasons using the stock pistons is not an option

I did speak to JE last night, and although i'd rather go with someone like Arias, they claim to be able to make exactly what I want without going through the hassle of drawing up a completely new piston design. Maybe i'll give them a shot - the delivery times are quick too at only 2-3 weeks.

Many thanks,
Stu

 

[elliot400]

Good luck with that, I wish I knew enough to help a little. I'm good with bolt on stuff. Once you get much lower than the cams, I'm useless. Again, good luck! E-

 

[HTPerformance]

Right now I am getting my head ported and polished with larger valves put in.

Focus-power is making a 2.3L stroker kit and has/ or can make any piston from 9-14.5:1 compression ratio. I believe last time I talked with the owner Tom, he has a set of 12.5:1 on the shelf.

I plan on doing the lower end of my car sometime soon, beginning with a WRC block and building it up with my SVT head and such.

Let me know what other info you want.

Cheers,
Brian

 

[UTlapso]

actually I am a Mechanical engineer thank you. I calculate things I do not throw parts together.

 

[saqmaster]

actually I am a Mechanical engineer thank you. I calculate things I do not throw parts together.

I don't remember saying anywhere that I was "throwing it together". If something is beyond your experience or understanding, don't assume someone else hasn't planned and designed it. My question was wholly regarding the difference in the UK and US spec zetec engines, it didn't require a debate. If you don't know the answer to the question, it's probably best not to reply! :coolman:

 

[UTlapso]

I don't remember saying anywhere that I was "throwing it together". If something is beyond your experience or understanding, don't assume someone else hasn't planned and designed it. My question was wholly regarding the difference in the UK and US spec zetec engines, it didn't require a debate. If you don't know the answer to the question, it's probably best not to reply! :coolman:

First off I never said anything to insult you. I even said "I am not saying you don't know what you are doing" and "not to be rude". I did answer one of your questions, I pointed your 2000 focus question to the right forum. Also you are asking a question that you should not find by word of mouth. You need to contact people supplying the parts which I saw you later did. Also I do happen to know a lot about how cars are built. I am a product engineer for drivetrain components and have been to fords romeo, MI testing facility many times. I tried to word it nicely. So why act like that and question my knowledge. I may not be in charge of designing motors but I have more training and experience then most. That is why I said the thing about throwing parts together because they were not designed or ment to.

You are in a SVT focus forum asking questions you should look up yourself about a normal focus. So why try to rip on me when I pointed you in the right direct and gave you good advice.

What are you, a baker, butcher or candlestick maker? Are you a professional engineer that can make judgement?

All I have to say is that one bit you in the butt. May need to cut down on the nursery rhymes.

Also cool note; they have a couple SVT focus's at the test track that they use to teach new engineers how to drive consistently.

 

[rrmike1]

I would try focusfanatics. In my opinion your not really designing your dreaming of throwing together alot of focus parts and thinking they will work well together. I am not saying you don't know what you are doing but if you are about to lay down alot of money on your motor I would talk to some one experienced. Not to be rude

Your response to his query was out of line. Try answering the questions as they're asked instead of giving opinionated responses that make this board resemble a bunch of high-school ricers.

 

[UTlapso]

Your response to his query was out of line. Try answering the questions as they're asked instead of giving opinionated responses that make this board resemble a bunch of high-school ricers.

are u serious, this is getting out of hand here. I was the first to reply with where he should go.

 

[Primaris]

are u serious, this is getting out of hand here. I was the first to reply with where he should go.

Don't sweat it. You gave an answer and an opinion they gave you thiers. Just remember opinions are like assholes, everybody has one.