Who said it was going to be a big block? That's the backup plan.
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Who said it was going to be a big block? That's the backup plan.
You guys. A high revving 6G7X? I'm drooling for updates now. Subbed!
why not stick with the tall deck? You can use longer rods (all for the better of sustain high rpm use with the 6g72 crank) and you have the advantage of the 4 bolt mains (unless your using a 6g72TT block), with my thinking here, the only difficult part of using the 6g72 crank is getting bearings made thick enough for use within thin block, but that's just how I would approach thisQuote:
Originally Posted by M-Rod
oh well, good luck sir, I can't wait to see the results
also if I may ask this, would aluminum connecting rods be part of this build?
6G74 block and crank, bore over to 96mm, 6G75 heads, 7K+ rpm??
Why the hell don't you text me when you are working on your car. I can't come over everytime, but once in a while I'd like to help!
You underestimate the differences between the engines. As far as short blocks go the small block and big blocks are not compatible in any way shape and form. The 72 already has a rod to stroke ratio that can rev to 10k with factory geometry if you build it. The 72 main journals are so much smaller than that of the big blocks you simply couldn't get it in there. No shim or bearing would be stable enough support the rotating assembly.Quote:
Originally Posted by foxbrand
If you want a 4 bolt main 72 just go grab one from the 3000gt and throw your stuff in it. You'll need a 3000gt oil pump since the location of the filter mirrors that of the 74 and 75 otherwise everything is the same.
Revving the 74 over 7500 requires some pretty serious building. The 75 requires outright redisign to do so. If you wanted to get a big block to 8k you'd be looking at a 3.7 long rod. If I had known how to do it when I'd built my motor you better believe that's what I would've done...
The truth is no one has really even just straight up built a 3 liter and gone with it. TJ did but his build sucked ass (go ahead, crusify me). Aside the fact that he went through countless engines, his breathing support didn't really make sense. If you're going to build an engine you have to plan these things out to get exactly what you want. The 3 liter isn't really a torque monster in the way a 3.6 or 3.8 would be, so if Matt builds one it's going to be built to rev up. Doing so will require some pretty hardcore valve train attention but it should pan out just as well as it does for the 3000gt guys.
Good info. I believe the 3kgt is a big block 3.0 with a longer stroke where the 3.0 sohc is a small block with a shorter stroke. From what I gathered, the 3k rods would also be longer than the 3.0 sohc.
So technically if he were to build the 4-bolt main block, he would also need the 3kgt/6g74,6g75 rods and 3k crank?
You are incorrect, the 3000gt block is identical to our SOHC block minus the oil filter location and the presence of 4 bolt mains. The geometric is the same and so is the deck pattern for the heads. Our rods are the same as the 3000gt rods but we have different pistons to match the different cylinder heads and whimpier rod bolts. The 2g 3s and up use the same forged crank we use as well. That however is it for similarities.
The only real crank swap that can be done is between the 74 and 75 because they share journal sizes and rods but that means the pistons have to soak up the different in the crank throw and the combustion chambers are so different between them that you can't run a 75 piston in a 74 and vice versa.
That said, small block refers to both our block and the 3000gt block because they're the same thing geometrically. The 74 is the big block and that particular block is used in many applications. The 75 uses a 6g74 block that is bored 2mm over, they are otherwise identical; 4 bolt main, journal sizes, deck pattern, etc.
These are just a few details, I've spelled it out on club3g if you really want to know every difference. The moral of the story is: pick and engine and stick with it. The truth is given boost there is no number any of the 6g7 SOHC's can't hit. That said you've got to decide what you want from it. The 72 may only be 3 liters but it can still outpool any DSM. That said you'd benefit largely from revving it up for the exact same reasons the 3000gt guys do. If you want the ultimate in streetability then the 6g74 is your candidate. It stands on its own outside boost and spools even a giant turbo quickly giving you a power band that few motors can touch. The 75 is simply not a boost motor. The sleeves in the block get very thin when you overbore it and the cost of an engine (both the 4 digit purchase price and the fact that its the only SOHC 6g7 that requires rods to break 500hp) does not justify using it unless you're either going for a thousand whp or just want the groupie title "Boosted 6g75".
I have to reprogram my brain now lol. All I've ever known about cross referencing the 3kgt vr4 engine and the 3.0 sohc is a lie haha. Thank you sir.
Sorry for the thread clutter Matt. I can't wait to see your high rev build!
The 12v SOHC is incompatible to every other 6g7 ever created. When I say SOHC above I'm refencing the 24v series.
Pete, don't feel left out. The next step won't happen until late winter. Until then, it will just sit.
Keith, don't worry about the clutter. I'm all for technical info and discussion here, especially since it always seems so far and few between on our V6 platform.
A few new videos.
The first one is footage taken from earlier this Summer that never got edited until the other day. Just some driving videos with the GOPRO.
http://youtu.be/8RHT-Q-nREY
The second video is from today's MitsuStyle Dyno Day. Here are my 3 pulls.
http://youtu.be/J3LLpNiwL_k
And the dyno sheet. Best numbers I could get out of it today were 233whp/252wtq.
http://i169.photobucket.com/albums/u...5733494537.jpg
dude. thats pretty impressive. tuned?
Yeah that's damn good, the stock non-mivec 75 in the 9G was making 235 bhp, so for you to be making 232 at the wheels is awesome.
Thanks guys! Yeah it's finally tuned. Not quite to its potential but enough to do alright and be safe.
Just went and looked at some of your vids. Love the acceleration and sound of your G, definitely looks fun to drive. Clean interior btw
Congrats on the runs dude! Must be nice to see some numbers. I need to get on a dyno.
Is there any way I could persuade you to give me a running tally of how much your build has cost you?
My garage page had a total of everything before the forum update, but I'm not sure where it went. The purchase of the car was $3000, plus all of the parts add up to around $9000, which would put me at a total of around $12k.
They still have the Garage info, but with the update it isn't set up yet.