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jayc72 06-05-2007 01:33 AM

Built engine?
 
I'm thinking of rebuilding my engine over the winter. I can pretty much have the entire thing done for the cost of parts and machine shop time. All the parts would be at about dealer cost.

Since I'm going to be in there I figured at a minimum I'd do belfab rods. Is there anything else I might consider?

What effect would decking the block have to slightly raise compression?

Let hear those ideas.

RusMan 06-05-2007 02:11 AM

How much power are you planning to run?

Since you're there I'd do the pistions as well, wiseco's come in 8.5:1 compression, and JE come in 9:1 if you want to keep same compression ratio. You don't really want to go any higher than 9:1 with turbo.


Just read your sig, so buy a 1.8 and rebuild that.

hustler 06-05-2007 07:47 AM

I probably won't make enough power to justify it, but bought pistons and rods because I track the car about twice per month. I plan on making 230whp at the least. I wanted something ultimately reliable that I could drive from Dallas to Tulsa for track beatings.

Ben 06-05-2007 08:01 AM


Originally Posted by hustler (Post 120459)
I probably won't make enough power to justify it, but bought pistons and rods because I track the car about twice per month. I plan on making 230whp at the least.

Dude you should be 275+

If you only want 230, you should have got the 2554

Ben 06-05-2007 08:06 AM

Jay, what is your goal? Are you keeping your 1.6/greddy set up? If so, get some slight overbore oem pistons (.010/.020) and have the cylinders honed. Plenty strong, don't slap, and don't wear. Forged pistons, imo, are a mixed bag.

You could also consider some mild head work.

m2cupcar 06-05-2007 08:37 AM


Originally Posted by Ben (Post 120462)
Jay, what is your goal?

:werd: that has a lot to do with piston decision... and rods for that matter.

jayc72 06-05-2007 11:56 AM

My goal is to keep the 1.6 and the Greddy setup.

My plan right now is to refresh the engine and use belfab rods.

I guess the question is the Td04h. How much power can this turbo make? Will it become really ineffcient at higher boost levels (16+)? So is it worth the effort of bulding an engine that is capable of massive amounts of boost if the turbo is limited.

Then I started to think about compression. If I were to run higher compression could I make more power while not maxing out the turbo? If I did some head work in addition to the bottom end could I get a reliable 8500rpm limit? Is it even worth it?

Basically with using the Tdo4h and the limitations it has, what other supporting mods would I need to SAFELY make well over 250whp and beyond?

Newbsauce 06-05-2007 12:10 PM

You would need a 3" exhaust I would imagine.. to experience the full benefit of the built motor.

As far as building a 1.6.. as a bare build I would do pistons/rods/ARP studs/improved gasket. Thats what I am doing right now. I do not agree so much w/ OEM pistons... because it just makes sense in the long run to stick forged pistons in now, rather then having to open that engine up again.

Ultimately, you aspirations might take you past the limits of the TD04, however, as a smart ass I must remind you, aspirations require you to actually INSTALL the turbo on the car first ;)

jayc72 06-05-2007 12:17 PM


Originally Posted by Newbsauce (Post 120550)
You would need a 3" exhaust I would imagine.. to experience the full benefit of the built motor.

As far as building a 1.6.. as a bare build I would do pistons/rods/ARP studs/improved gasket. Thats what I am doing right now. I do not agree so much w/ OEM pistons... because it just makes sense in the long run to stick forged pistons in now, rather then having to open that engine up again.

Ultimately, you aspirations might take you past the limits of the TD04, however, as a smart ass I must remind you, aspirations require you to actually INSTALL the turbo on the car first ;)

My name isn't hustler ;)

My turbo is fully installed and taking a beating on a daily basis.

Exhaust will be happening this winter. I'm building a garage and plan to purchase a welder and the first learning project is going to be exhaust and new IC setup.

May I should build it and run NOS? Two bottles ... the big ones.

Ben 06-05-2007 12:23 PM

Your turbo can push air for 275 hp. Is there anything wrong with your current bottom end?

Why do you want the 8k rev limit--so you can play in boost a little longer, or do you want to stay in gear on the track?

If your bottom end is good, consider just going through the head. Give it a good port and polish, back cut the intake valves, and unshroud them. You'd gain a bunch of power. If you want the high rpm capability, you'll want to replace the springs and get some cams. But you'd probably want to replace the rods too.

jayc72 06-05-2007 12:38 PM

Nothing is wrong (yet) with the engine. It's just a matter or time since it is fairly high milage. I'd rather plan to rebuild it over the winter when the car will be parked rather than do it in the middle of the sunny season.

I know my engine is on borrowed time, especailly with turning up the boost. I originally though that if I ended up toasting my current engine I'd import a JDM engine since they can be had fairly cheap. Two people I know recently that have sourced engines from Japan have had issues with them. And for not a lot more money I can rebuild my current engine and know it is "100%".

My thinking is if I'm going through the expense what else should I do? To me the rods are a no brainer. The head work might be worth while, and I can get a spare head for really cheap.

Part of it is to build it up just to do it.

I guess the question I should ask is what will forged rods get me over running a stock bottom end? What can I do with boost? My tune? Am I less prone to knock? Is knock less of an issue?

magnamx-5 06-05-2007 01:08 PM

do a 40 over and some forged pistons why not belfab pistons as well. the td04 with 428 cfm of flow at 15psi will be your limiting factor you could possibly get 275 or so whp out of it as Ben said. Or you could take this as an opportunity to upgrade your turbo setup sell your greddy to a newb and go t3s60 or something similiar for 300 or so whp.

Newbsauce 06-05-2007 02:10 PM

Rofl sorry for some reason I was thinking Hustler started the thread. Honestly the most you can do w/ the 1.6 is a .06 (wiseco). I would do .04, that way if you EVER wanna have it rebored you have some space, albeit not much. 476 for pistons and rings, 95 HG, 289 belfab, 100 ARP... full bottom end. If you choose to do a head you could always do it separate and save funds. See my review of raceeng.com for the parts.

Newbsauce 06-05-2007 02:12 PM


Originally Posted by jayc72 (Post 120565)
I guess the question I should ask is what will forged rods get me over running a stock bottom end? What can I do with boost? My tune? Am I less prone to knock? Is knock less of an issue?

Having the forged rods will get you a piece of mind at high PSI. My belfabs vs my OEMs were amazing. The Miata rods are scary weak. with my setup in the post above I'm looking for something like 17-19 psi daily.

fmowry 06-05-2007 03:16 PM

Do yourself a favor and build a 1.8. The extra displacement spooling a turbo (any turbo) is very nice. I've already done the built 1.6 turbo vs the current factory 1.8 with the same GT2560 and I wouldnt' go back to a 1.6.

Sure you'll have to go with a different manifold but you'll have everyting apart anyway, so it'll be trivial.

Frank

jayc72 06-05-2007 03:25 PM

Don't want to build a 1.8. Happy with the 1.6. Also if I stick with a 1.6 I won't have to source a 1.8 engine, which could end up being expensive ... they don't grow on trees here.

But thanks for the adivce.

hustler 06-05-2007 04:35 PM


Originally Posted by Ben (Post 120461)
Dude you should be 275+

If you only want 230, you should have got the 2554

We'll see what happens. I went with the bigger turbo because of my track addiction, and Corky's recommendation. The more I think about it...I'll probably put it at like 12 psi, and leave it at whatever power level it makes, and just baby the trans. The trans is what I fear most.

Jefe 06-05-2007 06:53 PM

Since your up north...
And there a more cold days then warm ones, I would opt for the 9:1 comp ratio, way back when I had a car with 7.5:1 it was a PITA to start when it was really cold out.

I think your plan for building the garage, then the motor is a good one :)

P.S. and no matter what size garage you choose, it'll still be too small...


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