to make you feel better, you will probably make more power with the same setup, using a standalone with a good tuner vs stock + piggybacks.
7MGTE - OEM Piston Capability Question
- Thread starter Grandavi
- Start date
yea you should always be able to make more power with a standalone... piggybacks might get you close. might. That's not a good word when you've got a lot of money put into it. I plan on just running a OE shortblock on VPC + AFC w/ a .67/.70 t4 and 550 or 560 cc inj. Just to see what'll happen. (head ported for street use) I'll also be having another 7m o-ringed 
for some serious seriousness
for some serious seriousness 
89jdm7m;1901462 said:yea you should always be able to make more power with a standalone... piggybacks might get you close. might. That's not a good word when you've got a lot of money put into it. I plan on just running a OE shortblock on VPC + AFC w/ a .67/.70 t4 and 550 or 560 cc inj. Just to see what'll happen. (head ported for street use) I'll also be having another 7m o-ringed
I wouldn't o-ring a 7M. My old motor was and it didn’t seem like a popular idea.
The rings end up being seriously close together. Mind you I never had an issue but was only running stock boost.
Pics or it didn't happen, right?
There is only like a millimeter between the rings.
this is true... I guess we'll see I've got 3 spare blocks. I know the one in the 89 I'm about to scoop is bored .40 over... there'd be no way. It is a bit close for comfort there in that pic, but I can't really see it being an issue... even if the rings were touching.
I think that for your stated service, you're getting a stilted view.
For your "day to day" boost of 14 PSI, you should be able to get to 350-375 WHP on stock electronics, Lexus AFM and 550s without a problem. You might get close to 400 with the piggybacks, and so long as you're taking time to examine your wideband logs to ensure that you're not drifting from the safe zone, your greatest risk is bad gas, and the standalone won't save you from that.
For your 21 PSI "scramble boost" again, that's something that the piggybacks can handle, and you can tune it with data from the wideband and the piggybacks. This isn't something that you'll be doing a lot, and you're not going to spend extended amounts of time at redline with that setup. This could get you over the 500WHP mark with a stand-alone, but will fall short with a safe tune on TCCS + piggyback.
Your intended use is very close to mine, and for similar reasons. As it happens your build is similar to mine, too. I've got the Arias pistons instead, but otherwise, it's not too different. I'll probably keep it under 20 PSI for mine, and I'll be happy with 450WHP. That said, my block is built for 600+ in order to give me some overhead.
Nobody is telling you that you don't need to be careful when playing with a lot of power, particularly not me, but I believe that at the power goals that you've specified, and with the stated mods, a stand-alone is not a requirement for you to get there.
For your "day to day" boost of 14 PSI, you should be able to get to 350-375 WHP on stock electronics, Lexus AFM and 550s without a problem. You might get close to 400 with the piggybacks, and so long as you're taking time to examine your wideband logs to ensure that you're not drifting from the safe zone, your greatest risk is bad gas, and the standalone won't save you from that.
For your 21 PSI "scramble boost" again, that's something that the piggybacks can handle, and you can tune it with data from the wideband and the piggybacks. This isn't something that you'll be doing a lot, and you're not going to spend extended amounts of time at redline with that setup. This could get you over the 500WHP mark with a stand-alone, but will fall short with a safe tune on TCCS + piggyback.
Your intended use is very close to mine, and for similar reasons. As it happens your build is similar to mine, too. I've got the Arias pistons instead, but otherwise, it's not too different. I'll probably keep it under 20 PSI for mine, and I'll be happy with 450WHP. That said, my block is built for 600+ in order to give me some overhead.
Nobody is telling you that you don't need to be careful when playing with a lot of power, particularly not me, but I believe that at the power goals that you've specified, and with the stated mods, a stand-alone is not a requirement for you to get there.
this is true... mk3 brent put down 630+ whp on a tired 7m (breaking up badly) (gt40-88, VPC) if you only want 400 or so whp... there really is no need for standalone...Dan_Gyoba;1901505 said:
89jdm7m;1901473 said:
Of course there's an issue, the o-ring is providing a very high load on a small contact patch, if the rings are close together this load becomes shared across the 2 rings so you get uneven loading around the ring and failure.
A 7M has to be one of the least applicible engines to o-ring (ALL of my previous Turbo engines were o-ringed but when I got my 7M I didn't go ahead)
A correctly installed MHG and a good tune is capable.
As for the standalone, while not "needed" it's nice being able to program in some measure of self protection/failsafe when you start pushing a production based engine this hard, people are talking about 400>500 rwhp being "easy" it's NOT if you want any sort of reliabilty/longevity...
the safety features of a standalone can save your motor too, ie boost/ignition/fuel cut when fuel pressure drops, overboost protection, etc
As for tuners, if you can't find someone local that's any good, make a road trip to BC (several good shops in and around Vancouver), or find someone nearby in the US.
As for tuners, if you can't find someone local that's any good, make a road trip to BC (several good shops in and around Vancouver), or find someone nearby in the US.
IJ.;1901511 said:
After reading through this entire post, IJ, glad you made that note... I read posts talking about running a motor under certain conditions for a couple of years or 10,000 miles... if the ability to run a setup for 10-20k is a benchmark for "it works"... personally that does not for me... for me, if it is not comparable to OEM reliability with added HP/TQ then imo there is an issue with the setup or how hard it is being pushed. I am sure I could push my setup further and gain more HP/TQ, but my logs say I am safe, my EGTs say I am safe, as much as I enjoy working on the Supra, I still enjoy driving it more
IJ.;1901511 said:
After reading through this entire post, IJ, glad you made that note... I read posts talking about running a motor under certain conditions for a couple of years or 10,000 miles... if the ability to run a setup for 10-20k is a benchmark for "it works"... personally that does not for me... for me, if it is not comparable to OEM reliability with added HP/TQ then imo there is an issue with the setup or how hard it is being pushed. I am sure I could push my setup further and gain more HP/TQ, but my logs say I am safe, my EGTs say I am safe, as much as I enjoy working on the Supra, I still enjoy driving it more
My whole purpose to the engine build/upgrades was to have a Supra that is damn fun to drive, rock solid.. and out of the shop long enough to enjoy a summer for once...
Hasn't occured yet.
Not interested in dyno-queening it or putting it on a track (although running a couple quarters just to find out what it does would be really nice.. lol). Its just my reward for raising 6 kids and having to live with mini-vans...
now I wanna forget Im a parent once in a while and put the pedal down and feel a bit of G-force push into the seats...
My thinking for "having to" go to stand alone is that I do not want to be sitting in a shop listening to numbers that tally enough to go out and buy a new car again... this build has been a bit painful. Opted out of the OEMs for safety, now I'm thinking that its a 50-50 proposition and if your not gonna top 550+ hp, your probably better off sitting with OEM's
Boost-wise though, I am wondering if the max 15 psi is an actual number for OEMs or if its a safety range. Ideally, I would like to do 2-3 21 PSI pulls a year... and the rest of time run at 14-15 psi. (which would still be far better than the stock run I am used to)
The hardest part about building my shortblock is that most of the builds discuss the power potential and talk about parts, but very few of them talk about the engine physics. From what I have been running across, every single item on the 7MGTE needs to be looked at closely. For instance.. I replaced the block heater (a cool Canadian item) and replaced with a frost plug simply because the car doesnt run in winter (one corrosion item gone). The oil pump has been shimmed 5 mm (and is new) to help with oil pressure and hopefully increased flow. The EGR was removed simply because it failed on the old motor and was baking everything at the back of the engine. Its unmonitored and I opted to remove it simply because I dont believe it will affect the overall durability/performance of the engine in the long run. (I believe it was a "knock-reducer")
The list is long in reality, so I am really glad I am not building it myself. I'm not a gearhead and the last engine I built was a 1200 cc engine for my 72 Corolla (which I put the thrust bearings in backwards and destroyed the crank).
I think the forged overall are better just because they give a larger variance for problems, but the OEMs would probably have been well suited for my 400'ish build desire. Kinda wish I would stayed OEM from what I am reading so far. (not complaining about having Wiseco's, but the extra $$ could have been used elsewhere)
just a tiny note about thrust bearings... if your drinking beer.. dont put them in.. lol. I was facing the bench, and had everything aligned properly.. but turned around to put them in (right became left.. and beer refused to let me acknowledge it)... instead of swapping hands and putting them in, I swapped hands, flipped the bearing and voila... instant dead crank
luckily a rebuilt engine only cost 1200.00 for that car..
Hasn't occured yet.
Not interested in dyno-queening it or putting it on a track (although running a couple quarters just to find out what it does would be really nice.. lol). Its just my reward for raising 6 kids and having to live with mini-vans...
now I wanna forget Im a parent once in a while and put the pedal down and feel a bit of G-force push into the seats...
My thinking for "having to" go to stand alone is that I do not want to be sitting in a shop listening to numbers that tally enough to go out and buy a new car again... this build has been a bit painful. Opted out of the OEMs for safety, now I'm thinking that its a 50-50 proposition and if your not gonna top 550+ hp, your probably better off sitting with OEM's
Boost-wise though, I am wondering if the max 15 psi is an actual number for OEMs or if its a safety range. Ideally, I would like to do 2-3 21 PSI pulls a year... and the rest of time run at 14-15 psi. (which would still be far better than the stock run I am used to)
The hardest part about building my shortblock is that most of the builds discuss the power potential and talk about parts, but very few of them talk about the engine physics. From what I have been running across, every single item on the 7MGTE needs to be looked at closely. For instance.. I replaced the block heater (a cool Canadian item) and replaced with a frost plug simply because the car doesnt run in winter (one corrosion item gone). The oil pump has been shimmed 5 mm (and is new) to help with oil pressure and hopefully increased flow. The EGR was removed simply because it failed on the old motor and was baking everything at the back of the engine. Its unmonitored and I opted to remove it simply because I dont believe it will affect the overall durability/performance of the engine in the long run. (I believe it was a "knock-reducer")
The list is long in reality, so I am really glad I am not building it myself. I'm not a gearhead and the last engine I built was a 1200 cc engine for my 72 Corolla (which I put the thrust bearings in backwards and destroyed the crank).
I think the forged overall are better just because they give a larger variance for problems, but the OEMs would probably have been well suited for my 400'ish build desire. Kinda wish I would stayed OEM from what I am reading so far. (not complaining about having Wiseco's, but the extra $$ could have been used elsewhere)
just a tiny note about thrust bearings... if your drinking beer.. dont put them in.. lol. I was facing the bench, and had everything aligned properly.. but turned around to put them in (right became left.. and beer refused to let me acknowledge it)... instead of swapping hands and putting them in, I swapped hands, flipped the bearing and voila... instant dead crank
luckily a rebuilt engine only cost 1200.00 for that car..
Grandavi;1901604 said:
If you are talking boost only... I can answer to my personal experience - I am running 18psi on a 57Trim, with water/meth, prior to the w/m I was running 16 consistently trying to stay 11.2 on AFRs with min/max of 10.8 to 11.5; this is with a MaftPro piggy back yet with no timing control at this point. This is stock internals, though a fresh build 12k miles ago. IMO I am in a safe zone, I have not dyno'd since adding the water/meth and the 2 psi.
always good to hear from those with more experience... I've only seen one o-ringed 7m (disassembled, not in a car), never even heard anything about anyone doing it until now. I may have to put a hold on that project if it's such a bad Idea.IJ.;1901511 said:
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