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.
I'll shot him an email, thanksgianttomato 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.
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.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 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.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.
Kool man, I just found your e-mail address. Ed what are your thoughts on a good cam choice?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