Does anyone actually rev their 7M?

oneandgone

oneandgone

40R 6 SPD SC3
Mar 30, 2005
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I know Brian aka chevyeater was planning to spin his 9K, but I don't know if he's been doing it yet or not. IIRC it's sporting Pauter rods, stock crank, and Ross pistons for a bottom end. Top end wise, IIRC it's sporting a/m cams along with the standard Ferrea components one would expect. Plus one more thing...shimless buckets.

So, anyone else spinning the stock crank? How fast? How often? And with what piston/rod combo??
 
siman

siman

Lifetime Ban
Mar 31, 2005
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8K seems to be a good number. Unless we had ultra small strokes like an RB series motor, there is really no apparent need to rev to those limits....

I would like to see a 7500rpm rev limit on mine...with cams I have heard from a guy with FIRST HAND experiance that the car just wants to KEEP on pulling past 6800 ( 88> ecu/ motor(crank? 6m/7m)). Just some retainers, valve springs and maybe new valves...we could see those limits...though a GOOD oiling system would be needed...none of that 40psi checkvalve crap....

putting some reducers into the heads oil gallies would aid in keeping valuble oil in the bottem end ( increasing pressure)...since our heads just saturate themselves with oil.....I read about this cricumstance on TOMEI's website...ist something I would like to experiament with....I think someone should if they have the resources.

as for the stroke, planely you could rev the 7m to 9K rpm...HKS had a destroker kit to 2.8ltrs and revved their HKS mk3 drag 7m to 9K and it made OVER 800hp......so its DOABLE...

but with money, anything is possible though...right IJ!



-Jonathan
 
suprabad

suprabad

Coitus Non Circum
Jul 12, 2005
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Down Like A Clown Charley Brown
I'm thinking that shot peened rods and welded crank journals with good bearings and everything maticulously balanced should make 9k a relativly safe endevor. But I'd like to hear it from somebody who's been there w/ the 7m.
 
I

IJ.

Grumpy Old Man
Mar 30, 2005
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SB: I'd be a bit ummmm errrrr "worried" spinning old rods to 9K no matter how good the prep there are some enormous loads at those sorts of engine speeds! (Stock rods have the oil squirter hole in the beam which adds a "Cut along dotted line" failure point)
 
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tubbie

tubbie

Yes, powerful Jedi....
Apr 4, 2005
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Back in the early nineties, there was an article in Turbo magazine of someone in FL that had a 7m that reved to 8500rpm making 500+ hp. He used a NA intake manifold, cause through testing he found it flowed more evenly to all the cylinders. I can't seem to find the article anywhere, but if someone has that old turbo magazine, it would greatly help our cause.
 
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figgie

Supramania Contributor
Mar 30, 2005
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i know Melloyello used to spin to 8k without issues. Stock stroke

but i have harped on this.

S54 from BMW. Same 91mm stroke as the 7m. Yet they spin to 8k. If we can update the head. That means we should be able to get our motor spinning to 8k without any issues.
 
supra90turbo

supra90turbo

shaeff is FTMFW!
Mar 30, 2005
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the motor i'm building is a revver.

i've always loved high-rev engines. i'm hoping for something like 8500....


Ian, look for another clone sometime within the next couple years over here. lol
good to know you guys are running those components. makes me feel like i definetely chose the right parts.

someone tell me more about the head pooling too much oil? i would like to hear this...
 
I

IJ.

Grumpy Old Man
Mar 30, 2005
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Kurt: Chev V8's had a problem when running hi volume Oil Pumps with pumping the pan dry as it couldn't drain back fast enough and restrictor kits to limit the amount of top end oil were the rage!

Don't know if it applies to a 7M and I'm not sure if I'd want to experiment as our cams need a good supply of oil being plain bearing units.
 
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chevyeater

wastegate hose is pulled
Mar 30, 2005
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I have had no oil control problems up to 8k so far. Another 7M I'm doing some work on does just fine @ 7500 as well. No restrictors in in the oil feed to the head on either. IMO, we have trouble getting enough oil to the head, not too much...
 
supra90turbo

supra90turbo

shaeff is FTMFW!
Mar 30, 2005
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thanks for clearing the air guys. a little misinformation goes a looooonnnnggg way!!
i had been a bit skeptical about that statement as i've heard nothing about it until just now...

sweet. one less thing to worry about. woohoo
 
spoolint78

spoolint78

Representing T.O
Mar 30, 2005
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i'm building my motor as we speak.
The head willl be stock for now, but i plan on building one on the side.
I plan to rev to 7500rpm, but not sure what i need to do to the head.

Valve's, springs, retainers, maybe dual springs?
 
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