ETS Quick spool Turbo kit(G30)
Small turbo's like the g25/g30, especially with a stock or stock-ish intake manifold (like the Skunk2) still typically make peak power around 7500, and def not after 8000, so revving them past 8500 really gets pointless. I wouldn't count on this kit letting you rev the motor to 9000 or higher.
I would only actually need the header and turbo, all the exhaust in IC piping I can make with my buddy. They wont be quite a fancy as the ETS artistry but it will be much cheaper and easy to repair/replicate if needed. My buddies car won Lucky Dog here with an Audi turbo 5cyl in a Porsche 924. And he made the manifold and all piping that survives 12h days.
I have 4.11 gears so I hit 76 in 2nd at 8k. But I can push the revs more on the 2.2 than I am, so going to 4.31 or even 4.53 (stock) and revving to 8500 wouldnt be too much a change in speed limit but 8500 would drop rpms ~300 @ 30mph. Thats a big enough difference in response that Im playing that trade-off game of threshold and torque to ground vs max speed in gear.
So far, 76 is higher than necessary. Ive hit that limit 1 time in 2 years. But the stock gearing I hit the 67mph limiter every.single.event. Just because it pulled harder and stopped sooner. So happy medium, 4.31 and 8250-8500 rpm may be the sweet spot. A soft limiter would also make things less violent when I do hit the limiter.
So far, 76 is higher than necessary. Ive hit that limit 1 time in 2 years. But the stock gearing I hit the 67mph limiter every.single.event. Just because it pulled harder and stopped sooner. So happy medium, 4.31 and 8250-8500 rpm may be the sweet spot. A soft limiter would also make things less violent when I do hit the limiter.
Power falling off is one thing but is it detrimental to the motor is what I'm trying to better understand. I've been reading up on this and seems I might be confusing myself the more I learn. Being out of compressor just seems that, well its out of compressor whereas is power falling off bc EMAP is rising with RPM which is causing the gate(s) to open? My point is Im OK with power falling off if it isnt pissing off the motor bc of it.
Then it gets into max speed per gear. Admittedly I didnt think about EMAP on my last build and just thought if bottom and top end can support then revs then rev it out. Will power fall off? Of course but how often am I above 8 grand realistically? Shifting to 3rd is a nonstarter and hitting the limiter if it can be avoided that seems ideal. I kept my limiter on stock motor at 8300 for years and also hit it literally every single event which sucked. Back to max speed per gear. Last season I ran stock FD 9400 limiter 295/30 yielded 79mph in 2nd. I basically never hit the limiter (did a couple times but Devens is decently fast when it comes to autox). I loved everything about that setup gearing wise but perhaps the motor couldnt handle the revs.
So then the option is taller FD and lower the revs. The car should stay in the meat of the powerband vs having to rev out where it may fall off. But at the same time it seems I was almost always in the powerband with stock gearing. And as long as you can put power down the car will accelerate harder with shorter FD so still makes me question if taller FD is actually faster in this circumstance?
Reality is without data this is all just speculation. I just want my car back to where it was bc I felt it was perfect but perhaps it was a ticking time bomb in its form and the same fate is in its future.
Then it gets into max speed per gear. Admittedly I didnt think about EMAP on my last build and just thought if bottom and top end can support then revs then rev it out. Will power fall off? Of course but how often am I above 8 grand realistically? Shifting to 3rd is a nonstarter and hitting the limiter if it can be avoided that seems ideal. I kept my limiter on stock motor at 8300 for years and also hit it literally every single event which sucked. Back to max speed per gear. Last season I ran stock FD 9400 limiter 295/30 yielded 79mph in 2nd. I basically never hit the limiter (did a couple times but Devens is decently fast when it comes to autox). I loved everything about that setup gearing wise but perhaps the motor couldnt handle the revs.
So then the option is taller FD and lower the revs. The car should stay in the meat of the powerband vs having to rev out where it may fall off. But at the same time it seems I was almost always in the powerband with stock gearing. And as long as you can put power down the car will accelerate harder with shorter FD so still makes me question if taller FD is actually faster in this circumstance?
Reality is without data this is all just speculation. I just want my car back to where it was bc I felt it was perfect but perhaps it was a ticking time bomb in its form and the same fate is in its future.
With a turbocharged engine more rpm is more backpressure. Some people add insult to injury and timing is added as well. It could make good power on the dyno once, but whats taking place after a few rev limit runs, hotter engine,hotter IAT's etc. If the back pressure is too high its got no where to go and its harder on parts. That also makes for a dirty cylinder since it can't get the air out. Some good articles out there on this.
As far as gearing goes, I personally ran the 4.53,4.31,and 4.11. The 4.11 was way nicer for me for the road course/street. A fat power band and could focus more on driving then shifting. I feel that if you have enough power that the taller gear is easier to manage wheelspin, wheelhop,driveline abuse and its faster. Not apples to apples but the faster drag cars use a tall first gear/final drive to calm the gearing down along with a clutch valve, and custom acd t case management. Remember, we all have Rally cars (short gearing) that we are doing non rally things with at much higher HP.
I ran my car for a few years and on a roll could run 30-32 psi in first on the 4.11 and the car would spin slightly but instantly move thru the gear. Second gear powerslides were also more manageable and the car would react the same way. You could just floor it and didn't need to pedal it.
Fast forward to putting the 4.31 in . I could only get away with 27-28 psi in first with alot of spin. Second gear power slides were the same and you need to pedal it off the rev limit. The 4.31 test was done on the same tires, then a newer version of them with the same results. My car makes 460-500wtq at 3800-4200 and it snaps on as violent as you want it to. You can soften the hit with timing/throttle/boost. Going off my fully calibrated butt dyno the 4.31 was slower for me on the street where I spend the most time. 4th gear also only goes 130 @8000 vs 142-144@8000 so theoretically slower out the top in the 1/4 mile then before. The MHI housing also starts to fall off at 7600 so a taller gear is a good idea for me also if I wanted to drag race more.
My .02 that if anyone moves to the 4.31/4.11 that they do an evo 8 first gear. For a high powered drag car the evo 9/4.31 combo would be my choice along with a magnus clutch valve to slip the clutch on the launch.
As far as gearing goes, I personally ran the 4.53,4.31,and 4.11. The 4.11 was way nicer for me for the road course/street. A fat power band and could focus more on driving then shifting. I feel that if you have enough power that the taller gear is easier to manage wheelspin, wheelhop,driveline abuse and its faster. Not apples to apples but the faster drag cars use a tall first gear/final drive to calm the gearing down along with a clutch valve, and custom acd t case management. Remember, we all have Rally cars (short gearing) that we are doing non rally things with at much higher HP.
I ran my car for a few years and on a roll could run 30-32 psi in first on the 4.11 and the car would spin slightly but instantly move thru the gear. Second gear powerslides were also more manageable and the car would react the same way. You could just floor it and didn't need to pedal it.
Fast forward to putting the 4.31 in . I could only get away with 27-28 psi in first with alot of spin. Second gear power slides were the same and you need to pedal it off the rev limit. The 4.31 test was done on the same tires, then a newer version of them with the same results. My car makes 460-500wtq at 3800-4200 and it snaps on as violent as you want it to. You can soften the hit with timing/throttle/boost. Going off my fully calibrated butt dyno the 4.31 was slower for me on the street where I spend the most time. 4th gear also only goes 130 @8000 vs 142-144@8000 so theoretically slower out the top in the 1/4 mile then before. The MHI housing also starts to fall off at 7600 so a taller gear is a good idea for me also if I wanted to drag race more.
My .02 that if anyone moves to the 4.31/4.11 that they do an evo 8 first gear. For a high powered drag car the evo 9/4.31 combo would be my choice along with a magnus clutch valve to slip the clutch on the launch.
Last edited by Abacus; Jan 28, 2020 at 02:12 PM.
Originally Posted by heel2toe
Power falling off is one thing but is it detrimental to the motor is what I'm trying to better understand. I've been reading up on this and seems I might be confusing myself the more I learn. Being out of compressor just seems that, well its out of compressor whereas is power falling off bc EMAP is rising with RPM which is causing the gate(s) to open? My point is Im OK with power falling off if it isnt pissing off the motor bc of it.
Then it gets into max speed per gear. Admittedly I didnt think about EMAP on my last build and just thought if bottom and top end can support then revs then rev it out. Will power fall off? Of course but how often am I above 8 grand realistically? Shifting to 3rd is a nonstarter and hitting the limiter if it can be avoided that seems ideal. I kept my limiter on stock motor at 8300 for years and also hit it literally every single event which sucked. Back to max speed per gear. Last season I ran stock FD 9400 limiter 295/30 yielded 79mph in 2nd. I basically never hit the limiter (did a couple times but Devens is decently fast when it comes to autox). I loved everything about that setup gearing wise but perhaps the motor couldnt handle the revs.
So then the option is taller FD and lower the revs. The car should stay in the meat of the powerband vs having to rev out where it may fall off. But at the same time it seems I was almost always in the powerband with stock gearing. And as long as you can put power down the car will accelerate harder with shorter FD so still makes me question if taller FD is actually faster in this circumstance?
Reality is without data this is all just speculation. I just want my car back to where it was bc I felt it was perfect but perhaps it was a ticking time bomb in its form and the same fate is in its future.
Then it gets into max speed per gear. Admittedly I didnt think about EMAP on my last build and just thought if bottom and top end can support then revs then rev it out. Will power fall off? Of course but how often am I above 8 grand realistically? Shifting to 3rd is a nonstarter and hitting the limiter if it can be avoided that seems ideal. I kept my limiter on stock motor at 8300 for years and also hit it literally every single event which sucked. Back to max speed per gear. Last season I ran stock FD 9400 limiter 295/30 yielded 79mph in 2nd. I basically never hit the limiter (did a couple times but Devens is decently fast when it comes to autox). I loved everything about that setup gearing wise but perhaps the motor couldnt handle the revs.
So then the option is taller FD and lower the revs. The car should stay in the meat of the powerband vs having to rev out where it may fall off. But at the same time it seems I was almost always in the powerband with stock gearing. And as long as you can put power down the car will accelerate harder with shorter FD so still makes me question if taller FD is actually faster in this circumstance?
Reality is without data this is all just speculation. I just want my car back to where it was bc I felt it was perfect but perhaps it was a ticking time bomb in its form and the same fate is in its future.
If it were just out of compressor, it would maintain power. 60lb/min is still 600hp, whether it's 8k rpm or 9k rpm, but the engine needs more airflow as RPM goes up, so torque drops. But RPM is going up with the torque drop, so power maintains or doesn't fall off as sharply. But since we have back pressure issues, power drops as torque drops much more sharply.
Your 7670 is further compounded by a .92 a/r T4 twinscroll exhaust housing. These cars usually want a 1.15 or 1.3 a/r T4 divided hot side to not run into serious back pressure limitations.
And as Abacus said, back pressure is heat, heat is the enemy.
It's certainly detrimental, and revving a car 1500-2000rpm past peak power is not ever faster
Thanks for the feedback guys. Really don't want to derail this thread but the talk about gearing and responsive turbos and wide powerband just seemed fitting. I think the reality is I need some concrete data and the only way to get that is with logs/ dyno sheets. Yes power is falling up top however butt dyno really doesnt feel that way. As in stock turbo certainly fell hard above 6 grand and BBK Full seemed to start falling past 7 but the EFR just doesnt feel that way. Maybe it is, I'm sure it is falling but dropping off hard, IDK.
Im more concerned about back pressure right now than what is considered faster. Im not revving it out to 9 grand often as in maybe 1 or 2 quick element will require revs above 8 grand. My point is 98% of the time I am right in the meat of the powerband 4-8 so regearing just to eliminate that 1 time I rev higher seems like Im compromising lateral accel for the rest of the time.
That being said if that one time I rev it out hurts my motor and continues to do so then its not sustainable and at that point then I would agree its stupid. And I think the only way to know whats going on is to log EMAP or maybe even EGTs to see truly how much heat is being generated due to the backpressure up top and reassess then.
Im more concerned about back pressure right now than what is considered faster. Im not revving it out to 9 grand often as in maybe 1 or 2 quick element will require revs above 8 grand. My point is 98% of the time I am right in the meat of the powerband 4-8 so regearing just to eliminate that 1 time I rev higher seems like Im compromising lateral accel for the rest of the time.
That being said if that one time I rev it out hurts my motor and continues to do so then its not sustainable and at that point then I would agree its stupid. And I think the only way to know whats going on is to log EMAP or maybe even EGTs to see truly how much heat is being generated due to the backpressure up top and reassess then.
https://www.evolutionm.net/forums/ev...vs-7670-a.html
7670. peak power of 556 at 7500. Down ~40whp by 8400. That's at only 25psi. That's also with S3's and mivec. If running more boost, it'll make more peak power, a bit earlier, and fall faster. You have cams with less duration (R2's) and no mivec, so its likely power falls off faster after peak as well.
Great, this thread is no longer solely about the Gseries.
The data exists. You're just not looking at it correctly.
7670. peak power of 556 at 7500. Down ~40whp by 8400. That's at only 25psi. That's also with S3's and mivec. If running more boost, it'll make more peak power, a bit earlier, and fall faster. You have cams with less duration (R2's) and no mivec, so its likely power falls off faster after peak as well.
Great, this thread is no longer solely about the Gseries.
The data exists. You're just not looking at it correctly.
I havent ever seen a stock intake manifold, ported or stock, make good power on a small turbo past 7400. Revving to 9400 on a 7670 (which I have had on the dyno with and without a Magnus) is pointless. Running 3rd gear at lower rpm or a final drive swap and staying in 2nd is what you need to do to keep things together. Revving high for no reason is for ricers.
Riiight bc this entire thread has been on point and solely in regards to the Gseries...
I am simply asking a question and you keep coming back with power is falling up top so its dumb to rev it out. If 98% of the time Im under 8 grand we're only talking about the 2% here. That graph shows power is down like 40hp from peak power but its still over 5 and more power than its making at 6 grand for that matter. Not to mention going to taller FD say the 4.31 yields difference of couple hundred RPMs relative to the 4.53 and down low that couple hundred can be the difference from being on boil and bogging out of a corner. Ramp up is pretty steep(looked to be delayed on purpose in the charts but im still seeing a ~60hp difference)
Shifting to 3rd is a nonstarter so this is really about taller FD and when it makes sense. I dont want the revs to be cool or to be a ricer. Its is 100% simply for the extra MPH in the rare occasions where I need to rev it out which generally isnt the case.
So again please forget about what you think is faster bc I dont think its a one size fits all approach. A tighter slower course should favor shorter gearing vs a more open fast course should favor taller gearing. What im trying to understand is if revving the motor is detrimental to the motors health. From the sounds of it, yes it is and the reason is due to backpressure. So if thats the case then I would like to log EMAP to see where Im at and adjust accordingly with a more appropriate rev limiter and potentially a taller FD to get back to the MPH Im after given the revs.
I am simply asking a question and you keep coming back with power is falling up top so its dumb to rev it out. If 98% of the time Im under 8 grand we're only talking about the 2% here. That graph shows power is down like 40hp from peak power but its still over 5 and more power than its making at 6 grand for that matter. Not to mention going to taller FD say the 4.31 yields difference of couple hundred RPMs relative to the 4.53 and down low that couple hundred can be the difference from being on boil and bogging out of a corner. Ramp up is pretty steep(looked to be delayed on purpose in the charts but im still seeing a ~60hp difference)
Shifting to 3rd is a nonstarter so this is really about taller FD and when it makes sense. I dont want the revs to be cool or to be a ricer. Its is 100% simply for the extra MPH in the rare occasions where I need to rev it out which generally isnt the case.
So again please forget about what you think is faster bc I dont think its a one size fits all approach. A tighter slower course should favor shorter gearing vs a more open fast course should favor taller gearing. What im trying to understand is if revving the motor is detrimental to the motors health. From the sounds of it, yes it is and the reason is due to backpressure. So if thats the case then I would like to log EMAP to see where Im at and adjust accordingly with a more appropriate rev limiter and potentially a taller FD to get back to the MPH Im after given the revs.
I'm talking about both. You're losing time revving it past 8500 or so, and its hard on the motor with you're setup. The issues you had speak to that. Don't need to log emap to know its going up up up to a problem area with how power drops even at 8400 in the above charts. Remember that R/TErnie has longer duration cams AND a Magnus V5 intake manifold AND the larger AR external gate hot side. All of which offer wayyyy better overrev vs the R2's and the stock ported intake you're running.
My car for example (R2's and stock ported intake) drop from 600whp at 7200 to 500whp at 8500. It's over 500whp at 5600. Your car with with same cams and manifold, and the smaller internal gate hot side probably make peak power 3-500rpm earlier than R/TErnies results, and falls off harder. This is another reason why street tuning a car sucks. You really don't know. But through looking at other results and knowing how different parts effect the curve, it's easy to see.
But I think this is the 5th time we've talked about this now. So it's turning into beating a dead horse tbh.
My car for example (R2's and stock ported intake) drop from 600whp at 7200 to 500whp at 8500. It's over 500whp at 5600. Your car with with same cams and manifold, and the smaller internal gate hot side probably make peak power 3-500rpm earlier than R/TErnies results, and falls off harder. This is another reason why street tuning a car sucks. You really don't know. But through looking at other results and knowing how different parts effect the curve, it's easy to see.
But I think this is the 5th time we've talked about this now. So it's turning into beating a dead horse tbh.
Last edited by letsgetthisdone; Jan 29, 2020 at 11:57 AM.
Evolving Member
Joined: Aug 2017
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From: NM
Going off ETS website, this is a jack-of-trades turbo. But it has to fall in line somewhere right? If i dont sell me car this year, id like to upgrade my turbo either an mhi red or 18k. But the thought of 600+/-whp with stock spool sounds awesome. Sounds like the g30 would be significantly better than either of those in every way. I tried to follow along this entire thread but i am a bit lost.
I'm talking about both. You're losing time revving it past 8500 or so, and its hard on the motor with you're setup. The issues you had speak to that. Don't need to log emap to know its going up up up to a problem area with how power drops even at 8400 in the above charts. Remember that R/TErnie has longer duration cams AND a Magnus V5 intake manifold AND the larger AR external gate hot side. All of which offer wayyyy better overrev vs the R2's and the stock ported intake you're running.
My car for example (R2's and stock ported intake) drop from 600whp at 7200 to 500whp at 8500. It's over 500whp at 5600. Your car with with same cams and manifold, and the smaller internal gate hot side probably make peak power 3-500rpm earlier than R/TErnies results, and falls off harder. This is another reason why street tuning a car sucks. You really don't know. But through looking at other results and knowing how different parts effect the curve, it's easy to see.
But I think this is the 5th time we've talked about this now. So it's turning into beating a dead horse tbh.
My car for example (R2's and stock ported intake) drop from 600whp at 7200 to 500whp at 8500. It's over 500whp at 5600. Your car with with same cams and manifold, and the smaller internal gate hot side probably make peak power 3-500rpm earlier than R/TErnies results, and falls off harder. This is another reason why street tuning a car sucks. You really don't know. But through looking at other results and knowing how different parts effect the curve, it's easy to see.
But I think this is the 5th time we've talked about this now. So it's turning into beating a dead horse tbh.
I know you guys are chomping at the bit for Evo results, but this is from an STI with a built motor, g30-770 kit. I don't know any other details, but these are solid results. And FWIW, the 4g63 will usually spool faster and make more power on the same turbo vs the EJ25.
Last edited by hokiruu; Jan 29, 2020 at 03:12 PM.