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Discussion Starter #1
As most of us are getting in there and ripping our beloved 7m's to pieces and swapping some new mhg's and rod bearings what are some of the weak points of the 7m, i've heard people speak of them after going through 3+ motors. Yet they really didn't go into detail.

Do i have to go through all the same mistakes they did just to learn there same lessons or is the information going to present itself while i can make a move to increase my strength and performance of my beloved 7m.

Well known problems
- Low torqued Hg
- Needs oil to work (rod knockage)
- Valve Cover screws back off

What else is there?

For my own personnal building plans, i'm going for a strong motor that's going to be rev hard, lot's of engine braking(not the bad type), quick shifts and very hard(no powershftin), Not looking for a dyno queen, or even a 1/4 mile monster. Something that will be able to help me and do some damage in the Scca competitions around the country. Yes the car will be lightind and suspension will be done. But when it comes to building this motor what are some of the weak points that we can upgrade and solve with the forever torquey 7m.

Thanks in advance for you wisdom and guidance. :beerchug:

(i'm not really worried about spool time and fuel)

:D
 

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wastegate hose is pulled
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What are your power goals? How you build depends alot on that. The more power you want, the less stock stuff will work, just like any engine.
 

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Discussion Starter #3
From what i know i'm doing to the motor.

Getting the stock rods shot-peend and balanced fittd w/ arp.
-030 with ross pistons
-already have the na cams, hoping to see what my sponsor can get on that side, already have ported exhaust side
- going w/ oversized valves on the exhaust side(prob intake valves)
- Major port work
-maybe dual stage valve springs
-custom Big Ex. Mani
-Super terrific trd intake mani

Shooting for somewhere of 400+ or whatever i can keep on the tarmac really, so if that's 500+ then so be it. Whatever i can do to be competitive and match my aggressive driving that's what it'll be. I'm not sure on what hp numbers scca upper classes run but i would like to be in that area.

I'm thinking opening the coolant passages, reverse flow of the coolant,(no thermosat either way). whatever to make the motor more efficeint. Def the full motor ass. will be balanced.

I'm sorry if i'm being to generic but i'm just asking what people have seen happen with there highly modified 7m's and problems they had, and what they did to solve them.

ty chevy eatr for the question (what's the deal with eyesupra.com)

oh yeah arp everything just for piece of mind.
 

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The Beginning
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Head Gasket (ARP Studs and Metal Head Gasket take care of that), definitely some kind of oil pan redesign cause this motor treats it oil level like a terminally ill patient on life support. You will need a better design to make sure it is getting the oil it needs. Also the exhaust ports are way small. Definitely do major porting and polishing on that.
 

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Discussion Starter #5
def. will be working on a new design for the oil pan, i'll see if the tranny gasket chart at work matches closely with our pans design, maybe we'll get lucky and find a match.

Also the exhaust ports will be inlarged greatly more, to match new mani.

Also one more question, The lower the compression the better, race gas all the time?, not a car driven often(only when v8's need a ego check)

Thanks so far guys,

You guys rock.
 

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wastegate hose is pulled
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A full flow oil cooler isn't a bad idea either. Use the N/A filter adapter and a remote mount filter kit to plumb it in.

Edit: I dunno wtf happened to IS. It was down for a while and I just stopped checking back. Think they changed servers or something. :confused:
 

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Discussion Starter #7
well call me crazy(and you will) but one of my other main goals is to make this 7m as 50/50 weight distribution as i can. As that being said the oil filter(s) + the oil cooler will be moved to the back along with the battery and hopefully and almighty god letting the Radiator will be put in the place of the stock fuel tank with custom mounts and a new fuel cell will be put into the stock spare tire location(just like Horsepower Tv pro. Cuda).

I'm goin to have to do some crazy things to make this car into what i need to be, to out handle and out pull those porsche's and corvettes next year.

But yeah Big Oil Cooler
 

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wastegate hose is pulled
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What class exactly do you plan on running in SCCA? I'd go over the rules pretty carefully if you want to build a competitive car.
 

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Discussion Starter #9
gt-2 that's what are cars can be in.

We'll see, honestly besides scca, i just want to build a japanese supercar.

Nothing to much in one direction. Sorry i'm getting away from the thread, just trying to see what improvements and gains i can make to make this motor stronger and tougher.
 

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boostmastersdotcom said:
As that being said the oil filter(s) + the oil cooler will be moved to the back along with the battery and hopefully and almighty god letting the Radiator will be put in the place of the stock fuel tank with custom mount
But yeah Big Oil Cooler
Oil filter and cooler relocated to the rear? You will add weight making your goal of 50/50 defeated. I doubt the oil cooler/filter weigh much, even when full. Is it worth the extra lines?

As far as the rad in the rear, make sure you do extensive aerodynamic testing.

G'luck with the car, I have similar goals.
 

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boost freak
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-the stock bearings are fine

-rod knock problems stem from people running the 7M low on oil, its that simple. DON'T DO IT.

-you may want some stonger rod bolts, they seem to be the "weak link" in the bottom end.
 

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didn't someone advise against using the intake valves as exhaust valves? something about them metals not working well enough fo some shit. :dunno:
 

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boost hungry
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if my goal were about 300-350 rwhp at the most, would I have to wory about changing the mhg, and head studs only.
 

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Your Neighborhood Pikey
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Interesting ideas you have there... One thing that doesn't sound like a good idea is mounting a fuel cell in the spare tire location. That sounds bad to me because you'd be moving the fuel cell forward, but consider this. The fuel cell will be mounted higher in the car raising the center of gravity, which might kind of defeat the purpose of moving forward. However, if you cut the spare tire well out and then mounted the fuel cell as low as you can in the car, then you'd maintain a low center of gravity and move the weight forward. That would be a good idea, so long as you dont mind hacking up the body like that.

- Hams
 
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