7MGE Shortblock
- Thread starter supraman7mgte
- Start date
Can't PROPERLY be done, but hey, you can turbo anything !!
Search out some threads for 7mge to 7mgte.
Search out some threads for 7mge to 7mgte.
mrnickleye said:
Huh?
Lots and lots of people have done it. My na/t has a 7mge bottom end and I smoke the shit out of gte's all the time. In fact the slightly higher compression will actually work in your favor if the motor, turbo and safc are set up properly. You get all the tractability of an na with the punch of a turbo.
The only people I know who think a 7mge doesn't make a good turbo conversion are people who haven't done it or haven't done it correctly.
The only difference between a gte and an mge block is oil squirters for the pistons and domed lower compression forged pistons. That's it! And if you talk to someone who really knows they'll tell you the oil squirters suck! All's they really accomplish IMHO is to lower your already low oil pressure.
So don't believe this shit about 7mge's not being suitable for turbo applications.:nono: Only thing I would change is to go to a set of forged pistons like I have and even keep your compression at stock na of just below like I have and it's a great set up Hell, I used to run 12 lbs of boost on a stock 7mge block w/ no problems for a year untill I starved it for fuel and that was my mistake.
suprabad said:
a little mis info here.
i happen to like the oil squirters. my belief is that if you want higher oil pressure, get rid of the stock oil filter mount on the GTE's. it sucks, and oil cooling based on pressure is ridiculous. change that for a spin on adapter from an N/A block using a sandwich adaptor and a thermostatically controlled oil cooler and call it a day. benefits include: better oil cooling (based on temp, not pressure), and increased oil pressure because the stock filter mount is damn restrictive. another alternative is shimming the oil pump. they dont only starve us of oil pressure, they also lower the temperature of the pistons by constantly spraying them with oil to cool them down.
now, cooler pistons lowers the chances of detonation.
there's a benefit right there!as for turbo'd 7MGE's. i'd like to do it one day, or change out my turbo pistons for N/A pistons from my old motor. high compression turbo motors are wicked street machines, so long as they are tuned correctly. TUNING IS KEY!!!. i bet the number of 7m's that die due to rodknock, is about equal to those that are upgraded and not tuned correctly.
also, stock 7MGTE pistons are NOT forged. damn, i wish they were!
-shaeff
shaeff said:a little mis info here.
benefits include: better oil cooling (based on temp, not pressure), and increased oil pressure because the stock filter mount is damn restrictive. another alternative is shimming the oil pump. they dont only starve us of oil pressure, they also lower the temperature of the pistons by constantly spraying them with oil to cool them down.
now, cooler pistons lowers the chances of detonation.
as for turbo'd 7MGE's. i'd like to do it one day, or change out my turbo pistons for N/A pistons from my old motor. high compression turbo motors are wicked street machines!
also, stock 7MGTE pistons are NOT forged. damn, i wish they were!
-shaeff
Shaeff- I think your wrong to characterize what I said as misinfo.
While it may be your opinion (and others) that the oil squirters are the greatest thing ever, there are also plenty of people who don't think much of them. You must know plenty of people who don't think the benefits of oil squirters are worth the side affect, (lower oil pressure), especially with so many people using synthetic oils I just don't think they are necessary. And no matter how you try to gloss it over they lower the oil pressure, period.
I misspoke on the "forged" part of the piston description (please find it in your heart to forgive me) but they are aluminum and lower compression.
So c'mon shaeff be fair, you know as well as anybody that the stuff you call misinfo is a matter of opinion.
I'm just curious,I have a 7MGE shortblock with a Gude head that I was going to install in my old 87' 7MGE. It got totalled,and I was left with the motor and a 91' 7MGTE with over 165,000 on the clock.So I can still use the stock 7mge pistons?The oil filter upgrade is a definate go tho,the OG pressure type will BE LEAVING THE BUILDING!
Yeah, you can still use the 7mge pistons but your are going to have to be carefull about how much boost you run and your air fuel mixture, not to mention timing. I've done it, as have many others quite successfully.
The best would be (as long as you have the motor apart), to spring for some forged aluminium pistons. This way detonation worries won't be as bad, since the forged units stand up to pre-ignition much better.
Remember, in the higher compression mge engine running 10 lbs of boost is like running around 14-15 lbs (guesstimate) in a lower compression gte.
You gotta watch out for detonation. It's an engine killer.
The best would be (as long as you have the motor apart), to spring for some forged aluminium pistons. This way detonation worries won't be as bad, since the forged units stand up to pre-ignition much better.
Remember, in the higher compression mge engine running 10 lbs of boost is like running around 14-15 lbs (guesstimate) in a lower compression gte.
You gotta watch out for detonation. It's an engine killer.
suprabad said:
Actually, it is misinfo. The oil squirters have a spring loaded check valve and will only open at higher rpm's/psi. At idle and lower rpms they remain closed and have no effect on oil pressure.
what all do you need for a 7mge>t? I know you need the gte oil pump, injectors, turbo/manifold(duh), and a fpr wouldnt be a bad idea, neither would a bov, but what else?
u might want the turbo maf and u might want to get a piggyback system just to be safe with the air to fuel mixture but i still wouldnt run more than like 11 psi unless u get the other pistons like badsupra mentioned already, and depending on how u wanna be some people use the n/a cams which are an upgrade to the turbo cams but since ur now gonna run alot of boost i would use the turbo cams
by the way suprabad where would u suggest going to different pistons for the 7mge cuz i can only find lower compression pistons unless they only make them and im debating on whether using the na cams or the turbo cams
also instead of changing pistons i thought u could just get a thicker headgasket to lower the compression more
p5150 said:
And who do you know that drives their Supra at low rpm's?
I guess what your saying here is that the oil squirters only lower oil pressure at high rpm's...excellent...seems to me high rpm's would be the last place you would want lower oil pressure.
C'mon Shaef, you're killing me here. Why are you so in love with the oil squirters? You won't even admit lots of people don't like em? Do you own a piece of the oil squirter manufacturing company? LOL:biglaugh:
I think your gonna want to run the na cams, as I recall (somebody check me on this) the n/a cam has more lift and duration then the turbo cams.
As far as the pistons go, I'm checking on them and I'll get back to you.
I know alot of guys have used the thicker head gaskets to lower compression, but I agree with schaef...it's a bad idea. The additional clearance between the head and the block negatively affects the way the fuel is burned. It's not as efficient as the unaltered combustion chamber.
Plus I hear they are more likely to result in internal compression or fluid leakage.
Remember more compression is like raising the boost it puts additional stress on the internal components of your engine.
So...boost + higher compression = don't overdo it, increase the boost gradually, watching out for detonation and tune it right=dyno.
There is no substitute for a dyno tune on a turbo'd N/A.
:icon_bigg
As far as the pistons go, I'm checking on them and I'll get back to you.
I know alot of guys have used the thicker head gaskets to lower compression, but I agree with schaef...it's a bad idea. The additional clearance between the head and the block negatively affects the way the fuel is burned. It's not as efficient as the unaltered combustion chamber.
Plus I hear they are more likely to result in internal compression or fluid leakage.
Remember more compression is like raising the boost it puts additional stress on the internal components of your engine.
So...boost + higher compression = don't overdo it, increase the boost gradually, watching out for detonation and tune it right=dyno.
There is no substitute for a dyno tune on a turbo'd N/A.
:icon_bigg
suprabad said:
No, they DONT LOWER OIL PRESSURE. At higher RPM's, there is enough volume from your oil pump to compensate for those teeny tiny oil squirters.
Why do you think there is a relief on the oil pump?
To relieve/control the pressure at higher rpms.
not another one of these threads.
shaeff, p5150: please keep going.
suprabad: you are wrong. admit it, there was misinformation. lets leave it at that.
if you are unhappy or feel unsafe with oil squirters, just shim the relief on the oil pump. but not more than 6mm
the 7mgte is a "high volume, low pressure" oiling system. there's plenty of oil to douche the pistons at high rpms.
please dont let this turn into a flame war, it will get out of hand quickly. lets just converse on this topic calmly.
shaeff, p5150: please keep going.
suprabad: you are wrong. admit it, there was misinformation. lets leave it at that.
if you are unhappy or feel unsafe with oil squirters, just shim the relief on the oil pump. but not more than 6mm
the 7mgte is a "high volume, low pressure" oiling system. there's plenty of oil to douche the pistons at high rpms.
please dont let this turn into a flame war, it will get out of hand quickly. lets just converse on this topic calmly.