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Discussion Starter · #1 ·
How tight of a quench area can be safely used on a 7M? I've read as tight as 0.035, but that is really tight with stock rods.
 

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You should ask this on the mkiii board, this board is mainly for MKIV N/A's
 
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Discussion Starter · #4 ·
cheet said:
You should ask this on the mkiii board, this board is mainly for MKIV N/A's
No response there. By the way it says "NATURALLY ASPIRATED" NOT " MKIV NATURALLY ASPIRATED"
 

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all motor baby!
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Defiant, have you spoken to ed_ma61? He just built his 7MGE with a pretty tight quench area.

It's an NA area, yet somehow there's an awful lot of turbo chat in here too. I can't see the distinction between NA 5M, 5MGE, 7MGE or 2JZGE.
 

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DEFIANT_7M said:
No response there. By the way it says "NATURALLY ASPIRATED" NOT " MKIV NATURALLY ASPIRATED"

Notice how I said "mainly MKIV", not all. Relax champ. Just trying to guide you in the right direction.
 
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Discussion Starter · #8 ·
gianttomato said:
Defiant, have you spoken to ed_ma61? He just built his 7MGE with a pretty tight quench area.

It's an NA area, yet somehow there's an awful lot of turbo chat in here too. I can't see the distinction between NA 5M, 5MGE, 7MGE or 2JZGE.
I'll shot him an email, thanks

He and I seem to be on the same quest. Mine is just a little wilder with 14:5 commpression.

Turbo Chat............yea I noticed that.
 
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Discussion Starter · #9 ·
cheet said:
Notice how I said "mainly MKIV", not all. Relax champ. Just trying to guide you in the right direction.
I'm Kool.........just a little tired of the negative censure.
 

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all motor baby!
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I wouldn't recommend more than 12:1 on 98 RON fuel. It'll be detonation city.

Also you may find 490 thou lift is an awful lot of lift to cram on to a 28mm bucket - talk to a cam grinder and get their expert opinion - it might be possible with an awful lot of duration. Failing that, it is possible to bore out the bucket bores to accept a bigger bucket - Gen3 3SGE buckets are 31mm and Nissan FJ20 buckets are 34mm. I know there are 500 thou plus grinds that will sneak on to a 31mm bucket. You could shoot Tighe Cams an email and get their advice. They have over 5000 cam profiles on offer.

I have seen the flow figures you generated from the 7MGE head but can't seem to find the thread. That much lift (490 thou) may actually not generate any benefits with standard valve sizes even with berserk porting. Have you experimented with larger valves?
 
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Discussion Starter · #11 · (Edited)
gianttomato said:
I wouldn't recommend more than 12:1 on 98 RON fuel. It'll be detonation city.

Also you may find 490 thou lift is an awful lot of lift to cram on to a 28mm bucket - talk to a cam grinder and get their expert opinion - it might be possible with an awful lot of duration. Failing that, it is possible to bore out the bucket bores to accept a bigger bucket - Gen3 3SGE buckets are 31mm and Nissan FJ20 buckets are 34mm. I know there are 500 thou plus grinds that will sneak on to a 31mm bucket. You could shoot Tighe Cams an email and get their advice. They have over 5000 cam profiles on offer.

I have seen the flow figures you generated from the 7MGE head but can't seem to find the thread. That much lift (490 thou) may actually not generate any benefits with standard valve sizes even with berserk porting. Have you experimented with larger valves?
Thanks for the info. I'm way out of the box on this prodject. I have larger buckets from a 2000 Toyota Echo (on piece 31mm no shim very light). We have bored the head to accept them. I also have 2JZ valves. I have also made adjustable cam gears based of a kit for a 350 Chevy. That uses offset bushings in 0,2,4,6,8, -/+ degress. I will be using 110 octane fuel.

Here is the "Echo" shimless bucket

http://www.villagephotos.com/pubbrowse.asp?selected=630110

The 2JZ valves opened up the exaust side. Picking up 10 cfm with really a "quickie" valve job.

http://www.villagephotos.com/pubbrowse.asp?selected=453937


Adjustable cam gears.

http://www.villagephotos.com/pubbrowse.asp?selected=467869


This tread is really long.

http://www.supraforums.com/forum/showthread.php?s=&threadid=82444&highlight=head+flow
 
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Discussion Starter · #12 ·
Gianttomato are you using Tighe Cams? I have Schnieder regrinds(272s) now, but they don't look like they are going to work well for me.
 

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all motor baby!
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That sounds like a pretty mad 7MGE you're building up.

I got my cams made up by Clive Cams here in Melbourne. The owner Clive Stenalke used to work for Wade Cams (also in Melb) and is a cam genius. Friends of mine have used Tighe Cams and have found them to be OK.

I am running some 304 degree duration (262 @ 50 thou) with 0.435 thou lift. The 2JZ buckets are 31mm, the same diameter as the Gen 3 3SGE. I didn't know about those Echo 31mm shimless buckets otherwise I'd have used them. I know for a fact that Tighe has 490 - 500 thou lift grinds that will fit on the 31 mm buckets - I spoke to them direct.
 
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Discussion Starter · #15 ·
gianttomato said:
That sounds like a pretty mad 7MGE you're building up.

I got my cams made up by Clive Cams here in Melbourne. The owner Clive Stenalke used to work for Wade Cams (also in Melb) and is a cam genius. Friends of mine have used Tighe Cams and have found them to be OK.

I am running some 304 degree duration (262 @ 50 thou) with 0.435 thou lift. The 2JZ buckets are 31mm, the same diameter as the Gen 3 3SGE. I didn't know about those Echo 31mm shimless buckets otherwise I'd have used them. I know for a fact that Tighe has 490 - 500 thou lift grinds that will fit on the 31 mm buckets - I spoke to them direct.
Thanks again for the info. My goal is 300WHP (quietly looking for more). I've switched cams twice now so I need to nail down what I am going to use and stick with it. My flow numbers really get big @ higher lifts. At 350 thou they really start to move. I'll send Tighe a spec sheet and see what they say. Oh the Echo buckets come in 25 different sizes(heights). I found them for as cheap as $12.00, I spent like $16.00 or so for one. I think they weigh 28 grams.
 
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Discussion Starter · #16 ·
ed_ma61 said:
word is 28thou abs minimum squish clearance, opening up to 32thou. mine is 33/34thou to be safe :)

this is on stock rods
Kool man, I just found your e-mail address. Ed what are your thoughts on a good cam choice?
 
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Discussion Starter · #17 ·
Hey Gianttomato your set up sounds pretty mad too. So it's a 2JZ N/A? What kid of power are you getting from it? What's your idle like with your cams?
 

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all motor baby!
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The motor is not running yet. The head is finished (porting, big cams, shim under bucket conversion, heavy duty valve springs) and just sitting on the bench. I am waiting on pistons to bump the comp up to 11.7:1 and I am getting the crank lightened and rebalanced. Rods are being shot peened.

A friend of mine has the same grind in a 3SGE and you can barely tell that it has uber lumpy cams. However, the cam grind guys have told me to be a bit cautious - the same grind in an inline 6 will have a much hotter result (I was told why but the reason escapes me at the moment). The grind I am using has power from 4000 right thru till 8000 in the 3SGE, so I'm actually a little worried it might be a bit too much in the 2JZ.

The 7M (in standard guise) would certainly not like being above 8000 rpm for long - piston speeds are well over 4000 ft/sec - so this would mean forged rods and pistons for you (which by the sounds of it I'm sure you have those bases covered:) ).
 

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all motor baby!
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Here is a pic of the motor:


It is unopened, running 6 48mm throttle bodies and custom bend extractors. ECU control is by Motec M800. It is running 7MGTE 440cc/min injectors. It is producing 148 rwkW (about 250 flywheel horsepower).

Here is a pic of the head surface.

There are some pics of the porting on Ed's website.
 
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