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How can i lower engine compression on our car? head gasket maybe? upgraded stud kit? if someone has done it, or has ideas, where can i get it, and how do i do it? thanks.
 

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Usually it is done with different pistons. Why would you want to lower compression? Other than going with FI, there is no reason to do it
 

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i'm thinking bout doing a full custom turbo kit, so yes it would be for fi. how can i lower compression without major mods or money spent?
 

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Between custom, thicker head gaskets and $1,200 worth of cylinder head porting that together will net you at MOST 0.5 lower than factory. You could of just spent $800 for a set of Ross forged pistons.
 

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Discussion Starter #7
aight, thanks very much. i think i'll just do that then.


so what would you all recommend for engine build up? i know i need clevite bearings first since ours our weak. do i need rods? studs? i just want to know what i need for about 10 psi of boost? and which compression ratio. 8.5 to1?
 

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10's pretty high for an NA engine. You should probably try to stay in the 6-7 range.

Before you buy or do anything, I highly suggest starting research.

Here are a few books to check out.

Maximum Boost
http://www.amazon.com/gp/product/083760160...5Fencoding=UTF8

Forced Induction Performance Tuning
http://www.amazon.com/gp/product/185960691...glance&n=283155
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As a rule of thumb, yes, 6 to 7, but the Duratec is not on the thumb. Alot of 2.5L and 3.0L turbocharged Duratecs running around daily between 10 to 12 PSI. Though all of them have proper and extensive tuning too.
 

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Exactly. :)
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Runing any amount of boost without that tuning is just asking for trouble. Z6Speed did it temporarily, but noted what issues he was having.
 

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Runing any amount of boost without that tuning is just asking for trouble. Z6Speed did it temporarily, but noted what issues he was having.
[/b]

And still having (fuel issue with the injectors getting dirty), but hopefully soon enough Sniper Tuning will come out with something. Otherwise, I'll go with Unichip. Doing other things now to weigh the car down, so not really pushing the power issue right now, because that will just lead to other things needing to be done.

Tuning Options: Unichip out, SCT?, and Sniper Tuning?
 

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And still having (fuel issue with the injectors getting dirty), but hopefully soon enough Sniper Tuning will come out with something. Otherwise, I'll go with Unichip. Doing other things now to weigh the car down, so not really pushing the power issue right now, because that will just lead to other things needing to be done.

Tuning Options: Unichip out, SCT?, and Sniper Tuning?
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Could of sworn you sold the car.. oh well.

SCT works, it's just I am too broke to afford the local SCT authorized dealer/tuner with a Dynojet.
 

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Wouldn't it be cheaper to just buy a Noble 3.0L V6 Duratec that is primed for Turbo and has a lower compression already?
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For a bullet-proof Duratec, yes:

"For $4,400, from AER, builder of Noble 3.0L Duratec engines, you get:

We use a custom forged aluminum piston from Wiseco which results in a compression ratio of about 8.5:1

The rods are Scat's 4340 forged H-beam with ARP 2000 bolts. (These are not the Q-Lite version)

Standard green top, 42 lb Ford Lightning injectors.

In terms of balancing and blueprinting:
Each crank is rebalanced to match the weight of the new forged rods and pistons. Each block is checked for deck height, main bore size, etc. Heads and cranks and inspected as well. Due to small variations in piston size, we measure each and every one in our climate controlled quality dept and then make very closely matched sets of six. After this, each block is honed to match the set of six pistons. We do this in order to maintain very tight control over the piston-to-bore clearance to reduce the possiblilty of piston slap from the increased clearance requirements of a forged piston.

Other items which are different:
1) The camshafts are a unique profile with increased lift and duration.
2) The block is specially machined to install piston squirters on each cylinder.
3) The accessory drive setup requires a non-stock front cover.
4) We use a special dual frequency damper for engine smoothness. This is not an underdrive or lightweight type change.
5) Lighter weight 19 lb flywheel (SVT flywheel)"

Recoup some of the loss by selling the Noble heads (Which are nothing special BTW, just standard 2001+ 3.0L Duratec heads), swapping over your own cylinder heads. Then use that money you got off the cylinder heads and have your local SCT-authorized dealer/tuner with a dyno properly setup the tuning.

I wanted to do this, but several thoughts interfere with that in my mind:

1) For that price, I could buy a reman Toyota 4.0+ liter UZFE V8 and swap it in the 6 (Crazy!! Yet it is the latest fad to stick that engine in everything that has wheels and moves)

2) For just about that price, I could buy a crate 5.7L LT-5 or a Lingenfelter 383 LT-5 engine for the Fiero (This is the dominant thought, as I would be the first to ever complete such a swap).
 

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For a bullet-proof Duratec, yes:

"For $4,400, from AER, builder of Noble 3.0L Duratec engines, you get:

We use a custom forged aluminum piston from Wiseco which results in a compression ratio of about 8.5:1

The rods are Scat's 4340 forged H-beam with ARP 2000 bolts. (These are not the Q-Lite version)

Standard green top, 42 lb Ford Lightning injectors.

In terms of balancing and blueprinting:
Each crank is rebalanced to match the weight of the new forged rods and pistons. Each block is checked for deck height, main bore size, etc. Heads and cranks and inspected as well. Due to small variations in piston size, we measure each and every one in our climate controlled quality dept and then make very closely matched sets of six. After this, each block is honed to match the set of six pistons. We do this in order to maintain very tight control over the piston-to-bore clearance to reduce the possiblilty of piston slap from the increased clearance requirements of a forged piston.

Other items which are different:
1) The camshafts are a unique profile with increased lift and duration.
2) The block is specially machined to install piston squirters on each cylinder.
3) The accessory drive setup requires a non-stock front cover.
4) We use a special dual frequency damper for engine smoothness. This is not an underdrive or lightweight type change.
5) Lighter weight 19 lb flywheel (SVT flywheel)"

Recoup some of the loss by selling the Noble heads (Which are nothing special BTW, just standard 2001+ 3.0L Duratec heads), swapping over your own cylinder heads. Then use that money you got off the cylinder heads and have your local SCT-authorized dealer/tuner with a dyno properly setup the tuning.

I wanted to do this, but several thoughts interfere with that in my mind:

1) For that price, I could buy a reman Toyota 4.0+ liter UZFE V8 and swap it in the 6 (Crazy!! Yet it is the latest fad to stick that engine in everything that has wheels and moves)

2) For just about that price, I could buy a crate 5.7L LT-5 or a Lingenfelter 383 LT-5 engine for the Fiero (This is the dominant thought, as I would be the first to ever complete such a swap).
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Eh. Using that Toyota V8 might give you a better performing vehicle, but how lame that sounds. Oh no, it's another UZFE V8 in a car.

If you were to go with the AER, would you go FI?
 

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If you were to go with the AER, would you go FI?
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Most definately, slap that Whipplecharger on, crank the boost up into the teens and scream! Though losing my last job and having to accept a lowering pay one and also in the process of marrying and moving in, I am broke and these are just dreams.
 

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Most definately, slap that Whipplecharger on, crank the boost up into the teens and scream! Though losing my last job and having to accept a lowering pay one and also in the process of marrying and moving in, I am broke and these are just dreams.
[/b]
Yea, the way you lost your job is still fucked up. Did you resolve anything with your unemployment wages? Where do you work now? Is it in the same line of field as before?
 
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