dump valves - ill probably get slaughtered for asking this!!
#91
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RedWRX, WRC cars chatter due to having no DV, and they run on anti lag to compensate. And its hardly a comparison is it?
The arguent here (from me) is regarding performance anyway.
Lexus lights? Class....
MB
The arguent here (from me) is regarding performance anyway.
Lexus lights? Class....
MB
#93
Originally Posted by Dark Blue Mark
Jay MA - See my list of big power / boost cars. Remember, Forge do an uprated recirc.
Olly, see David's answer. And how did they map the fuelling on throttle lift? Id be most keen to know if they stopped the overfuel if its MAF based
MB
Olly, see David's answer. And how did they map the fuelling on throttle lift? Id be most keen to know if they stopped the overfuel if its MAF based
MB
I was just quoting chrispurvis100
#96
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Originally Posted by Dark Blue Mark
Jay MA - See my list of big power / boost cars. Remember, Forge do an uprated recirc.
MB
MB
Yeah but no but what I'm saying is it may not be good to recirc all boost back into the system if, say running 2 bar boost, some would suggest setting up a VTA to keep 1.5 in the system and dump the rest, IYSWIM
I have an uprated Forge recirc
cheers
#97
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Agreed to an extent Jay, but boost of that level generally isn't needed / can't be achieved due to the A/R's of turbo's generally fitted to Subaru's. GTR's and Supras' maybe...
List again:
Litchfield Type 25 - 1.4 bar and over 350 bhp
Spec C Subaru STi - Similar
Harvey's STi with nearly 600 bhp
TSL's 330 bhp 22B
John banks 400 bhp uk car
BRD's STi V5
David Wallis's monster
MB
List again:
Litchfield Type 25 - 1.4 bar and over 350 bhp
Spec C Subaru STi - Similar
Harvey's STi with nearly 600 bhp
TSL's 330 bhp 22B
John banks 400 bhp uk car
BRD's STi V5
David Wallis's monster
MB
#99
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If a car is mapped for a VTA without using the MAF, then yes, it will work properly and probably help protect your turbo. What I think most of us are trying to say is this: bunging a Vta onto a standard car WILL NOT give any increased performance whatsoever. It will not run efficiently because the cars original map is designed to accommadate a vta.
Metered air passas through turbo, into intercooler, into engine. If air escapes from the system, the original amount of fuel will still be injected along with a decreased volume of air. = rich mixture. Excess fuel in the chamber can seap past the piston rings and wash the oil off of the cylinder bore.
And as for hot air geting hotter by being dumped back into the intercooler, ITS AN INTERCOOLER, which usually means, well, it cools the air!
Metered air passas through turbo, into intercooler, into engine. If air escapes from the system, the original amount of fuel will still be injected along with a decreased volume of air. = rich mixture. Excess fuel in the chamber can seap past the piston rings and wash the oil off of the cylinder bore.
And as for hot air geting hotter by being dumped back into the intercooler, ITS AN INTERCOOLER, which usually means, well, it cools the air!
#101
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'now mine may be diff coz on low boost in 4th if u bring the boost on and slowly let off mine chatters along for ages and it never hisses not like a cheap one'
So its cheap if it hisses, and expensive if it chatters???
I like your deductive logic!
So its cheap if it hisses, and expensive if it chatters???
I like your deductive logic!
#102
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John, they chatter on part throttle as the spring / seat is pulsing slightly as its not quite sure where to be as the boost right on the setpoint of the spring tension - you can actually hold the throttle and hear it permenantly leaking boost.
MB
MB
#103
This must be the fastest topic on here today, I went to answer a question on page two and ended up on page six,
Nobdy is going to win as your all right in your own minds.......if your bothered in big BHP then you'll take time to listen to people who've been there and done it.
If you want your car to chatter or hiss when changing gear fit one, if you want it to make more horses or faster pick on the road, sell the 18'' wheels and go for 50 series tyres on 15'' wheels.
I don't have one on mine because I don't want one, if you have one on yours, I'm sure it sounds nice.
Jonah
Nobdy is going to win as your all right in your own minds.......if your bothered in big BHP then you'll take time to listen to people who've been there and done it.
If you want your car to chatter or hiss when changing gear fit one, if you want it to make more horses or faster pick on the road, sell the 18'' wheels and go for 50 series tyres on 15'' wheels.
I don't have one on mine because I don't want one, if you have one on yours, I'm sure it sounds nice.
Jonah
#104
And as for hot air geting hotter by being dumped back into the intercooler, ITS AN INTERCOOLER, which usually means, well, it cools the air!
Chris,
I never said that, my dv is pre-intercooler (94UK) so the air is put through the turbo, then put back through the turbo via the recirc, its not got to the intercooler yet.
I also have no illusions as to any performance gains
What I'm fighting against is the mindset that says:
"Don't put a VTA on your car or you'll die"
Chris,
I never said that, my dv is pre-intercooler (94UK) so the air is put through the turbo, then put back through the turbo via the recirc, its not got to the intercooler yet.
I also have no illusions as to any performance gains
What I'm fighting against is the mindset that says:
"Don't put a VTA on your car or you'll die"
#108
Originally Posted by ALi-B
Well, if the cat shatters and blocks the exhaust it will
Admittedly not seen a scoob with a shattered cat yet, but I've seen a few dead ones.
Admittedly not seen a scoob with a shattered cat yet, but I've seen a few dead ones.
#109
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LOL Ali
Yes, if it blocked up the cat, built up some fuel in there that auto ignited on the turbo and shot it into bits, firing blades through the bulk head, though the driver - you could in theory.... die by VTA!
Would make a great Darwin award
MB
Yes, if it blocked up the cat, built up some fuel in there that auto ignited on the turbo and shot it into bits, firing blades through the bulk head, though the driver - you could in theory.... die by VTA!
Would make a great Darwin award
MB
#110
Originally Posted by Dark Blue Mark
I will win They don't aid performance
MB
MB
I know VIAGRA it bad for your blood pressure but it still good fun at the time !!!!!
Jonah
#111
Originally Posted by Dark Blue Mark
LOL Ali
Yes, if it blocked up the cat, built up some fuel in there that auto ignited on the turbo and shot it into bits, firing blades through the bulk head, though the driver - you could in theory.... die by VTA!
Would make a great Darwin award
MB
Yes, if it blocked up the cat, built up some fuel in there that auto ignited on the turbo and shot it into bits, firing blades through the bulk head, though the driver - you could in theory.... die by VTA!
Would make a great Darwin award
MB
#113
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This thread has amused me once agin - come guys at the end of the day its each to their own I say
I have owned 2 scoobs and have tried VTA's on both of them. These being HKS and Forge VTA. On the first scoob I was convinced that the HKS had seen better days due to the increased Lag etc and jerky on/off throttle. So I bought a Forge VTA and whilst I didn't mess with the spring/shims etc it was worse! I had sold the HKS so couldn't reinstall it so decided to refit the original recirc (plastic oem) d/v. I was at that time running about 292BHP and could not believe how much difference the recirc made to the car. Accelearation was smoother, lag reduced and whilst I did miss the pops and bangs I stuck with it. Soon found however that the oem one was leaking a little under high boost conditions so decided to uprate to a Forge recirc....which was superb. Then bought my 2nd scoob - once again fancied a bit of whooosh and purchased a brand new HKS. I soon started suffering with the jerkiness when coming off the throttle etc and Lag seemed to be worse once again. I ran with this d/valve for about 2 months (I must admit that I do like the whooosh at times but for everyday use it would get on my t1ts). So purchased a Forge Recirc and smooth power delivery and better spool has been restored
I do not consider myself to be a techie and know the ins and outs of the differences between the 2 different types of dump valves - I personally go with how the car feels to me - not what I read on here or from a Magazine ! The VTA made the car feel quite rough at times and the lag and jerkiness when coming on and off the power would really pi55 me off. So I personally will always stick with an uprated recirc (and I know everyone says that the Oem one works fine). BUT as I have said before each to their own - I certainly won't judge another Scooby owner just cos he has a VTA fitted - come on I mean whats that all about ?
I have owned 2 scoobs and have tried VTA's on both of them. These being HKS and Forge VTA. On the first scoob I was convinced that the HKS had seen better days due to the increased Lag etc and jerky on/off throttle. So I bought a Forge VTA and whilst I didn't mess with the spring/shims etc it was worse! I had sold the HKS so couldn't reinstall it so decided to refit the original recirc (plastic oem) d/v. I was at that time running about 292BHP and could not believe how much difference the recirc made to the car. Accelearation was smoother, lag reduced and whilst I did miss the pops and bangs I stuck with it. Soon found however that the oem one was leaking a little under high boost conditions so decided to uprate to a Forge recirc....which was superb. Then bought my 2nd scoob - once again fancied a bit of whooosh and purchased a brand new HKS. I soon started suffering with the jerkiness when coming off the throttle etc and Lag seemed to be worse once again. I ran with this d/valve for about 2 months (I must admit that I do like the whooosh at times but for everyday use it would get on my t1ts). So purchased a Forge Recirc and smooth power delivery and better spool has been restored
I do not consider myself to be a techie and know the ins and outs of the differences between the 2 different types of dump valves - I personally go with how the car feels to me - not what I read on here or from a Magazine ! The VTA made the car feel quite rough at times and the lag and jerkiness when coming on and off the power would really pi55 me off. So I personally will always stick with an uprated recirc (and I know everyone says that the Oem one works fine). BUT as I have said before each to their own - I certainly won't judge another Scooby owner just cos he has a VTA fitted - come on I mean whats that all about ?
#115
Bloody hippies^^^^^^^^^
Hey Karl, hows tricks?
Right, when the 2.5 is fitted and run in, I shall ask my tuner to map it with both the standard recirc and the VTA and ask him what the difference is.
Hey Karl, hows tricks?
Right, when the 2.5 is fitted and run in, I shall ask my tuner to map it with both the standard recirc and the VTA and ask him what the difference is.
#118
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Not bad matey thanks - these threads do make me chuckle What started off as a simple question and all that. Just go with the flow FFS whatever floats your boat - if you like VTA then go VTA if you don't then stick with Recirc. Is there much more to say ?
#120
Originally Posted by scoobyjohn2000
well chris i was under the understanding that u get what u pay for?
if u buy a dv for 300 and one for 40 the more expensive one should work better
plus its ajustable
if u buy a dv for 300 and one for 40 the more expensive one should work better
plus its ajustable
Jonah