GT_Fanatic
(Banned)
- 612
Blow off valve.
Turbocharger, Supercharger, or Naturally Aspirated?
- Thread starter Dark_Ryder
- 137 comments
- 7,569 views
Blow off valve.
it is blowoff, just not from the exhaust. called the blowoff valve. it releases pressurized air from the turbo piping when you let off the gas so there's no boost spikes.
edit: didn't see the above post.
- 1,629
- RedSuinit
Full boost at 2500 RPM? No, not possible, it may start spooling at 2500 RPM (and that's only if you have a turbo that is not stock, well never mind, that depends, what's the year and engine model?), but there is no turbo that reaches full capacity boost at 2500 RPM, period (unless you're running 8lbs. of boost or less.
)Luke
Full boost at 2500 RPM? No, not possible, it may start spooling at 2500 RPM (and that's only if you have a turbo that is not stock), There is no turbo that reaches full capacity boost at 2500 RPM, period (unless you're running 8lbs. of boost or less.
Luke
yeah i agree with that. there's no way he's at full boost at 2500RPM. but i think he was saying that it really gets to full boost at 3-4000RPM.
anyway, Red: where's jackson? i'm in clarksville.
- 96
- RalfMilo
Full boost at 2500 RPM? No, not possible, it may start spooling at 2500 RPM (and that's only if you have a turbo that is not stock, well never mind, that depends, what's the year and engine model?), but there is no turbo that reaches full capacity boost at 2500 RPM, period (unless you're running 8lbs. of boost or less.
Luke
Big diesel engines create full boost pressure at around 2500 rpm.
. but yea your right in a small displacement 4 pot you wouldnt be getting boost at 2500 rpm. at around 4000 rpm is when you'd really feal the turbo kick in.👍have you guys seen the turbo in the WRX? it looks like a bump in the inlet pipeing. I'm not talking about the STI just the little WRX turbo the TDO4. If i stab it at 2500 it takes about a 1/2 a sec to hit 15 PSI witch is full boost. I take a vid of it if i could.
GT_Fanatic
(Banned)
- 612
Full boost at 2500 RPM? No, not possible, it may start spooling at 2500 RPM (and that's only if you have a turbo that is not stock, well never mind, that depends, what's the year and engine model?), but there is no turbo that reaches full capacity boost at 2500 RPM, period (unless you're running 8lbs. of boost or less.
Luke
Or even 8000 RPM on a Spoon S2000 thats new. Max power boost kicks in at 3000 RPM and redlines at 8000 with the turbo still at full capacity.
- 1,629
- RedSuinit
So what, are you loosing all boost by 3500 RPM?
Your boost gauge is lying to you. The TD04 is capable of making 15 psi of boost on that 2.0 lt. engine, but it won't hold it, PERIOD (the safest recommended psi from the factory is 13.5 psi of boost, the only reason the TD04 will even make 15 psi and not blow up is because of that front mounted intercooler, that cools down that 2.0 lt. engine REALLY well), MUCH LESS at 2500 RPM. I know this for a fact. Would you like to see a DYNO of the GT28RS on a 1.8 lt. engine? It does not reach full boost till almost 5000 RPM, but it is spooling at idle (note: all because a turbo is spooling does NOT mean it is making full boost). All I have to say is that if your TD04 defies what I have said, then your torque curve must drop off like a rock.Oh and you can make a video of it, just go to www.conecam.com and buy one of their in car mounted cameras
I have GOT to see the DYNO for that, that is unbelievable, FULL boost at 3000 RPM and holding it all the way to red-line? That would be 5000 RPM at full boost. NO WAY, not unless you are using almost no boost (8 psi or less) There is just NO TURBO made to handle that, the only way that is even possible is if you have got a spark plug in the down-pipe igniting the exhaust fumes to keep the turbo spooling under braking, and that will destroy a turbo in one race (if this is a fully prepped race car, then I might believe it because they rebuild practically everything on those cars after every race. If it is a car that people can just buy, or is available as a spoon performance kit, that is street legal, I won't believe it until I see a DYNO).
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Any of you guys want to fix this for me since I can't delete my own post? 💡
GT_Fanatic
(Banned)
- 612
So what, are you loosing all boost by 3500 RPM?
Oh and you can make a video of it, just go to www.conecam.com and buy one of their in car mounted cameras
I have GOT to see the DYNO for that, that is unbelievable, FULL boost at 3000 RPM and holding it all the way to red-line? That would be 5000 RPM at full boost. NO WAY, not unless you are using almost no boost (8 psi or less) There is just NO TURBO made to handle that, the only way that is even possible is if you have got a spark plug in the down-pipe igniting the exhaust fumes to keep the turbo spooling under braking, and that will destroy a turbo in one race (if this is a fully prepped race car, then I might believe it because they rebuild practically everything on those cars after every race. If it is a car that people can just buy, or is available as a spoon performance kit, that is street legal, I won't believe it until I see a DYNO.
Nope. It kicks in at 3000 and holds it at 8000. If I told you where to get the video, i'd get blasted by the mods. pitty we don't live closer, you can come over and see it.
- 1,629
- RedSuinit
Then PM it to me, I don't doubt that it will spool at 3000 RPM but there is NO TURBO IN THE WORLD, that can produce full boost at 3000 RPM, AND hold it to the s2000's 8000 RPM red-line, at MAX BOOST. I'm telling you that there is no turbo. PERIOD. UNLESS you are using about 18lbs. of boost or less (and that is with better cams) the cams in the s2000 just wouldn't let 18 lbs. of boost flow into the engine above around 18 psi of boost. You will get a bottleneck effect and while you may actually hit over 18 psi of boost, but you will lose boost around 5000-5500 RPM. But I can't think of ANY turbo capable of that. The GT28RS is capable of hitting max boost around 3500 RPM and can hold it until about 7000 RPM that's a 3500 RPM range, and that is one of the best spooling turbos out there.
Now if they are using a twin turbo set up, that's a different story, but I doubt it.
Luke
Oh, and why would the mods blast you for posting a link?
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- 1,090
- Australia
- OnlineGT
Yep I'm with you on that!👍I have said it before and I'll say it again, The Mine's GT-R is an
absolute weapon!! There's a reason they call it the 'Ultimate Response Machine".
- 23,800
- Philippines
RE: maximum boost throughout rev range?
That might not be entirely consistent... but that's as close to flat as any boost curve I've ever seen. That's the GT-R R35... twin turbo, but non-sequential... the flatness of the curve is due to the VGT.
Many new OEMs spool fast, hit hard, and produce so much more boost than the engine can take that they cap the boost... giving you those weird, flat torque curves and boost curves. Those VGT turbos act like a small turbo at low rpms and a bigger one at higher rpms. You can't believe how incredibly linear those suckers are... not until you've driven them...
My non-VGT turbo hits maximum boost at around 8-10 psi at 2000 rpm.
Then falls back to 4 psi at 2500... damn diesel crap...
I've seen diesels that hit maximum torque (and likely, maximum boost) at 1800 rpm... and hold that till about 3600-4000 rpm... They can hold maximum boost till 5000 rpm... but whether the engines can take it is another matter. I've seen some of these diesels uncapped so that max boost doesn't peter off... fairly fun.
No turbo lag... but there is lag, of a sorts... electronic throttle lag... bummer... but that's something you can't get rid of, anymore... thanks to those damn emissions regulations.
----
In preference... Naturally Aspirated... followed by Supercharged... but since VGT has rendered the non-linearity of turbos obsolete... the question is moot. Linearity and ease of use now come down to programming.
That might not be entirely consistent... but that's as close to flat as any boost curve I've ever seen. That's the GT-R R35... twin turbo, but non-sequential... the flatness of the curve is due to the VGT.
Many new OEMs spool fast, hit hard, and produce so much more boost than the engine can take that they cap the boost... giving you those weird, flat torque curves and boost curves. Those VGT turbos act like a small turbo at low rpms and a bigger one at higher rpms. You can't believe how incredibly linear those suckers are... not until you've driven them...
My non-VGT turbo hits maximum boost at around 8-10 psi at 2000 rpm.
Then falls back to 4 psi at 2500... damn diesel crap...
I've seen diesels that hit maximum torque (and likely, maximum boost) at 1800 rpm... and hold that till about 3600-4000 rpm... They can hold maximum boost till 5000 rpm... but whether the engines can take it is another matter. I've seen some of these diesels uncapped so that max boost doesn't peter off... fairly fun.
No turbo lag... but there is lag, of a sorts... electronic throttle lag... bummer... but that's something you can't get rid of, anymore... thanks to those damn emissions regulations.
----
In preference... Naturally Aspirated... followed by Supercharged... but since VGT has rendered the non-linearity of turbos obsolete... the question is moot. Linearity and ease of use now come down to programming.
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nd 4 holden spd
(Banned)
- 6,142
- GTP_nd4holdenspd
- No, another PSN: nd4holdenspd
You obviously haven't seen when Top Gear tested the turbo lag on the Impreza.
No I haven't yet (when is that?).
Edited For Accuracy
To understand the lack of lag modern turbocharged cars have, you really have to have experienced turbo technology of old (as in, early nineties) when the gear was pretty much irrelevant! If you went from a constant throttle to flooring it, you'd have time to roll a fag, light it and smoke most of it before it came 'on boost'.
Oakey doak, but I don't smoke.
Um, what "modern turbos" are you thinking of. In order to get rid of turbo lag, you need a turbo that is basically a perfect match to your engine, and has a wicked spool, so that the turbo will be spooling at idle. I've only heard of maybe 3 turbos that can do this, and I've only heard of it being done on 1.8 to 2.2 liter engines. The only specific turbo I can think of is the Hass GT28RS (so SICK!) that someone I know put onto a MR2 Spyder, and it really does spool at idle. Turbo lag is no factor in his car, and it is so fast. (Making 220 RWHP, on a 2180 lb. car with a full tank and my freind in it) If I was to Turbo aan engine it would probably be the 3rd generation 3sGTE (standard engine in the 93 - 98 MKII MR2 or 93-94 in the U.S. because the didn't sell the 95 turbo in the U.S.) with the GT28RS (60mm bore) because that thing would also spool at idle leaving you with no turbo lag, but still reaching 200 ft-lb of torque at 3500 RPM
and reaching around 300-350 HP at about 6300 RPM, (depending on how well you tune the turbo) at the wheels with about 15 psi of boost. (Oh, and this car has a 7000 RPM red-line)
I have driven both an XR5 Turbo Focus (ST in Europe) and a turbo diesel Focus, both have little lag at all I can feel, and just look at the XR5's power graph in GT5
. Nissan GT-R R35 doesn't seem to have much lag, or the 911 Turbo, and many more. Pontiac Solstice has bad lag from what I hear.+1
Good point, I misunderstood his post, and as for the new STi, yes it has average lag. When I hear hardly any lag, I think 2250 - 2500 RPM or less, the STi? Stock the turbo kicks in around 3000 RPM, (REALLY bad lag is around 4000 RPM in my opinion) but as someone posted before, if you're complaining about lag, you're in the wrong gear. (Or are in first gear taking off)
The Litchfield Type 25 was designed by Litchfield to fit and perform excellently on the Subaru's 2.5 lt. engine, and the Typt 25 Subaru, heck it practically isn't a Subaru anymore with all those after-market parts put onto it. Plus the engine and Turbo on that car have been tuned to work together rather well, but even then it doesn't reach full spool until close to 2800 RPM.
You would have to tell me what diesels you are referring to. The only turbo diesel I hav experience with (Turbo diesels is not my cup of tea) had terrible lag, and this was the VW 1.8TD Jetta. But I do know that quite a few TD's out there use the VV turbos, which get excellent spool.
But even still as I said the number of turbos that can achieve this are few and far between, and need to be a practically perfect match to the engine that you are trying to turbo-charge.
And we're not even getting into boost threshold.
Luke
Turbo diesels seem to have, if anything, boost drop off. I guess being diesels manufacturers tune them for low rpm to work with the diesel, they all feel weak above 3000rpm.
So what, are you loosing all boost by 3500 RPM?
ok first off factory boost setting was 14.7 i raised it 1 psi with the ecu, and seconldy a lot of people run 18-19 psi on the TDO4. it wont live long at those boost levels but there cheap so some popel dont care. Have you ever seen a subaru before? what front mount intercooler? I have the factory top mount and no it dosnt cool the intake charge down very well. Yes my boost will not hold till redline at about 5500 it drops to around 11 psi and yes at that point power falls off big time. but it makes 300ft/lbs at 3000 rpm so im not gonna bitch it is a 2.0L.
- 1,629
- RedSuinit
What's the year and engine? The year and engine make a difference, because they started using the TD04 in 2007. From 2002 to 2007 in America they used the Mitsubishi TD05, which was originally put into the Subaru's because of the higher top end. Yes, I have seen one, in person up close, it had a front mount inter-cooler on it, it may have been after-market, but it was a front mount inter-cooler, I am NOT mistaking the inter-cooler for the radiator. I know the STi comes standard with a top mount inter-cooler, I am not as familiar with the plain WRX as I am the STi. The stock boost level I gave was the boost level recommended for the 2008 STi (note: the factory is going to tell you to run less than the turbo can actually handle, so I am sure that it can do more than that). I am going to do research on the TD04 tonight, and if I am wrong, I am wrong.
Also how close to stock is the car? Is it almost completely stock or have you done some engine modifications?
Do you have a DYNO curve? I wouldn't mind seeing that 300 ft/lb. of torque at 3000 RPM is pretty impressive. 👍
P.S. It's TD 0 4 not TD O 4
just so you know!Oh and please respect the AUP and your fellow users.
Acceptable Use Policy
Rereading my posts I realized I may have come across to others as a jerk, and I hope this is not so. But, if I have offended anyone, PM me and let me know because offending someone was not my intention.
Luke
New post without double posting:
Ok, after doing some research, (even though I still don't know the year and engine of the specific WRX I am talking about) on a 2.0 Lt. engine, from some of the DYNO's I have gone out and studied and the specs on the TD04, yes it can reach around 15 PSI of boost at 3000 RPM and hold it until about 5500 RPM, (but I still can't find anywhere, that someone has a DYNO and the specifics on how they reach 15 PSI of boost at 2500 RPM, however it does reach about 8-10 PSI of boost at 2500 RPM, this could explain why when you punch the gas while revving at 2500 RPM you get to 15 PSI of boost in about .5 sec, because it only takes about that long to reach 3000 RPM) the TD04 is a faster spooling Turbo than I originally understood, {I had several misunderstandings about the TD04, it is capable of holding close to 18-19 PSI of boost without hurting the turbo, and with that 8:1 compression ratio [this I did not know before about the Subaru WRX I though it was an 10:1 compression ratio (that makes a BIG difference in what the turbo can achieve), but after doing some research I have learned otherwise
]} but I still can't fathom a turbo spooling that quickly, you'll just have to tell me the specifics of the car, i.e. year, engine, any modifications done, etc. Also yes the front mount inter-cooler was after-market, there has never been a stock WRX with a front mount inter-cooler, they are indeed all top-mount inter-coolers.NOTE: I hope you don't see me as calling you a liar, I just think you might be confused, or your boost gauge might be off, that's all I am saying, so please don't take it as a personal attack, it's not. 👍
Luke
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the engine is bone stock all I've done is a SPT intake, after market up pipe, and full turbo back exhaust, and yeah all that (well except the intake) help it spool faster. its a 02 2.0L WRX. Hmmm i may have to do some looking my self i was positive it has the TD04. And yes you where right i did some runs on the way to work it dosnt hit 15 at 2500 but its darn close( if i do the run in 5th it will but thats cheatting ) . I dont have a dyno graph for it the Tq numbers i listed where from cobb using there stg 2 tune, i have changed to a opensorce tune and the car feels much better than it ever did with the cobb map but i dont know the numbers for this tune so i just use the cobb ones because i know im at, at least that.
) . I dont have a dyno graph for it the Tq numbers i listed where from cobb using there stg 2 tune, i have changed to a opensorce tune and the car feels much better than it ever did with the cobb map but i dont know the numbers for this tune so i just use the cobb ones because i know im at, at least that.
- 1,629
- RedSuinit
the engine is bone stock all I've done is a SPT intake, after market up pipe, and full turbo back exhaust, and yeah all that (well except the intake) help it spool faster. its a 02 2.0L WRX. Hmmm i may have to do some looking my self i was positive it has the TD04. And yes you where right i did some runs on the way to work it dosnt hit 15 at 2500 but its darn close( if i do the run in 5th it will but thats cheatting
Ah, so you have the EJ205 making 227 hp at 6000 RPM and 217 ft-lb of torque at 4000 RPM stock. Oops, I had it backwards they used the TD04 until 2007 then they switched to the TD05 for it's higher top end (on the STi). But the stock boost setting was 13.5 PSI (it was not the maximum recommended setting, so I was wrong about that).
With the modifications you listed are all meant to better the spooling of the turbo, so I can see your WRX making full boost around maybe 2800-2850. Your also probably making an extra 20 HP and 15 ft-lb. of torque over stock, probably reaching both of those about 250 RPM sooner. But you are also running 15 PSI of boost right? So you're probably making 280-290 HP and 265-280 ft-lb. of torque.
Luke
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- 1,885
- qld
- GTP_zed300 /zed300
- YA SAY WHAT?!!!!
I know this is a little off track but a Detroit diesel 855c.i.runs 2superchargers and 2 turbochargers giving it the highest reving engine in its class.This is like the best of both worlds. If you listen to a (I can only speak for Austalian) coach on the highway, these engines really sing some sort of song,they are easy to pick as they are a unique note.
- 154
- GTP_MrKipling43
It was Toluene - and it had the consistency of vaseline.
Some of you might recognise Toluene from the word Trinitrotoluene or, to give it its most common name, TNT.
IIRC there was only eight people who were allowed to mix the turbo era fuel and six of them have already gone to a very early grave.
- 606
N/A for me. Just the other day I was playing GT4 and put in stage 3 N/A tuning into my M3 GTR Race car.
I upped the power from 450 BHP to 630 BHP.
I had a look at putting in a turbo, and even a stage 4 turbo (with HUGE lag) only gives 613 BHP!
I was lapping Suzuka in under 1:50:00 after fitting the stage 3 N/A tuning!
I upped the power from 450 BHP to 630 BHP.
I had a look at putting in a turbo, and even a stage 4 turbo (with HUGE lag) only gives 613 BHP!
I was lapping Suzuka in under 1:50:00 after fitting the stage 3 N/A tuning!
- 135
- Twentyvalve
typically turbo. N/A if it has a smooth, usable power band.
hey h3rman, the reason, i believe, for your conclusion on the M3 is because BMW engines respond better to N/A tunning or supercharging than turbocharging in the real world so PD could have carried over that into the game.
hey h3rman, the reason, i believe, for your conclusion on the M3 is because BMW engines respond better to N/A tunning or supercharging than turbocharging in the real world so PD could have carried over that into the game.
- 793
so where is the engine?
i love how you can see the roots blowers under the intercoolers.
GT_Fanatic
(Banned)
- 612
- 58
- GTP_Dark_Ryder
- XBox sucks
turbos and superchargers are fun but they dont give the car anymore torque it just increases the horse power. Just remember theres no replacement for displacement. torque is what gives the car its pushing/pulling power,horse power determines how fast you get ther.
While i agree TQ is where its at, HP is after all just a result of a calculation based on TQ vs rpm (divided by 5250 i think) but id have to disagree big time on turbos not making torque. stock my mustang put down 215hp and 300FT/LBS at just 8psi it was 486hp and 460FT/LBSand it hit peak TQ at just a tick over 3000RPM thats some serious TQ production.
