Full Decat what benefit should there be ??
18 September 2004, 04:11 PM
#1
Full Decat what benefit should there be ??
Hi guys
just finished the Full decat on my98
Janspeed open neck downpipe,straight through center and magnex back box,
Intercooler hoses samco,
K+n panel,
I know its whistling arond 1500-2000rpm ?????then goes quite untill around 3000rpm???? and you can hear it dump loader
But what else should i notice ??
What gains should there be,
Sorry to sound a bit thick or perhaps i'm missing something....
Another question what next????
All help appreciated
just finished the Full decat on my98
Janspeed open neck downpipe,straight through center and magnex back box,
Intercooler hoses samco,
K+n panel,
I know its whistling arond 1500-2000rpm ?????then goes quite untill around 3000rpm???? and you can hear it dump loader
But what else should i notice ??
What gains should there be,
Sorry to sound a bit thick or perhaps i'm missing something....
Another question what next????
All help appreciated
18 September 2004, 07:46 PM
#2
Originally Posted by morpheous
Hi guys
just finished the Full decat on my98
Janspeed open neck downpipe,straight through center and magnex back box,
Intercooler hoses samco,
K+n panel,
I know its whistling arond 1500-2000rpm ?????then goes quite untill around 3000rpm???? and you can hear it dump loader
But what else should i notice ??
What gains should there be,
Sorry to sound a bit thick or perhaps i'm missing something....
Another question what next????
All help appreciated
just finished the Full decat on my98
Janspeed open neck downpipe,straight through center and magnex back box,
Intercooler hoses samco,
K+n panel,
I know its whistling arond 1500-2000rpm ?????then goes quite untill around 3000rpm???? and you can hear it dump loader
But what else should i notice ??
What gains should there be,
Sorry to sound a bit thick or perhaps i'm missing something....
Another question what next????
All help appreciated
18 September 2004, 07:59 PM
#3
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A Remap for what ? As the next step - maybe....
Morpheous, are you saying its made no difference to performance > If you've gone from standard to this, you should have added maybe 20-30 bhp...
Certainly, if its only making noise differences, something may be wrong.... ?
Should spool lower too.....
Next step is depends on the cash - For me, it was Dawes mbc, boost gauge, knocklink (engine knock detector - for visual readings) and an AFR (Air Fuel ratio meter)... The last 3 are to keep an eye on things and the mbc is to increase boost (whilst reading those meters/gauges..)
Hope this helps,
Mark
PS _ The whistling is normal, you can here the turbines and also get more 'whoosh', given that the car is not breathing through the restrictive filter (Are you feeding air through the original pipework/resonator ?) - You can also hear the D/V more...
Morpheous, are you saying its made no difference to performance > If you've gone from standard to this, you should have added maybe 20-30 bhp...
Certainly, if its only making noise differences, something may be wrong.... ?
Should spool lower too.....
Next step is depends on the cash - For me, it was Dawes mbc, boost gauge, knocklink (engine knock detector - for visual readings) and an AFR (Air Fuel ratio meter)... The last 3 are to keep an eye on things and the mbc is to increase boost (whilst reading those meters/gauges..)
Hope this helps,
Mark
PS _ The whistling is normal, you can here the turbines and also get more 'whoosh', given that the car is not breathing through the restrictive filter (Are you feeding air through the original pipework/resonator ?) - You can also hear the D/V more...
18 September 2004, 08:37 PM
#4
Cheers Mark
Just got back from a 40mile STEADY drive lol
Rite firstly theres a whistle not very loud before it goes onto boost around 1500---2000rpm which works on and off as you lightly push the throttle????
Maybe just spooling up faster and sooner ??? and more pronounced because of open neck downpipe no cats etc:
Then around 2600-3000rpm the things goes mentle and you hear a pronounced whistle from the turbo,its definetely better pulls really hard from nothing no matter what gear your in ie:5th at 1500rpm pulls easy up to boost,
As for the running now its same as before i can hear a bit of spitting when you decelerate sometimes but i think its the norm?
Not done airbox mod yet thats next
Definately looking for knocklink boost gauge and AFR meter if anyones got them or knows were best place to get
Cheers all
Big Smiler
Just got back from a 40mile STEADY drive lol
Rite firstly theres a whistle not very loud before it goes onto boost around 1500---2000rpm which works on and off as you lightly push the throttle????
Maybe just spooling up faster and sooner ??? and more pronounced because of open neck downpipe no cats etc:
Then around 2600-3000rpm the things goes mentle and you hear a pronounced whistle from the turbo,its definetely better pulls really hard from nothing no matter what gear your in ie:5th at 1500rpm pulls easy up to boost,
As for the running now its same as before i can hear a bit of spitting when you decelerate sometimes but i think its the norm?
Not done airbox mod yet thats next
Definately looking for knocklink boost gauge and AFR meter if anyones got them or knows were best place to get
Cheers all
Big Smiler
Originally Posted by markwild
A Remap for what ? As the next step - maybe....
Morpheous, are you saying its made no difference to performance > If you've gone from standard to this, you should have added maybe 20-30 bhp...
Certainly, if its only making noise differences, something may be wrong.... ?
Should spool lower too.....
Next step is depends on the cash - For me, it was Dawes mbc, boost gauge, knocklink (engine knock detector - for visual readings) and an AFR (Air Fuel ratio meter)... The last 3 are to keep an eye on things and the mbc is to increase boost (whilst reading those meters/gauges..)
Hope this helps,
Mark
PS _ The whistling is normal, you can here the turbines and also get more 'whoosh', given that the car is not breathing through the restrictive filter (Are you feeding air through the original pipework/resonator ?) - You can also hear the D/V more...
Morpheous, are you saying its made no difference to performance > If you've gone from standard to this, you should have added maybe 20-30 bhp...
Certainly, if its only making noise differences, something may be wrong.... ?
Should spool lower too.....
Next step is depends on the cash - For me, it was Dawes mbc, boost gauge, knocklink (engine knock detector - for visual readings) and an AFR (Air Fuel ratio meter)... The last 3 are to keep an eye on things and the mbc is to increase boost (whilst reading those meters/gauges..)
Hope this helps,
Mark
PS _ The whistling is normal, you can here the turbines and also get more 'whoosh', given that the car is not breathing through the restrictive filter (Are you feeding air through the original pipework/resonator ?) - You can also hear the D/V more...
19 September 2004, 09:03 AM
#5
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Sounds OK to me 
The on/off throttle noise at low revs is simply the air being drawn in, when you change the pressure at the airbox, due to it being open to the engine (on throttle) or not (closed throttle)...
Have Fun !
Mark
The on/off throttle noise at low revs is simply the air being drawn in, when you change the pressure at the airbox, due to it being open to the engine (on throttle) or not (closed throttle)...
Have Fun !
Mark
19 September 2004, 11:00 AM
#6
Sounds about rite it could just be the air being drawn in on slight throttle opening,It just sounds like a sucking through a small pipe like youve got a leak but been over it twice now and found nothing,
Anyway to end on a good note i'm off to do the airbox mod let you know later if it gets any more mentle lol
The best way to describe it at the moment is A rottweiler on steroids
Anyway to end on a good note i'm off to do the airbox mod let you know later if it gets any more mentle lol
The best way to describe it at the moment is A rottweiler on steroids
Originally Posted by markwild
Sounds OK to me
The on/off throttle noise at low revs is simply the air being drawn in, when you change the pressure at the airbox, due to it being open to the engine (on throttle) or not (closed throttle)...
Have Fun !
Mark
The on/off throttle noise at low revs is simply the air being drawn in, when you change the pressure at the airbox, due to it being open to the engine (on throttle) or not (closed throttle)...
Have Fun !
Mark
19 September 2004, 08:45 PM
#7
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i hate the noise mine makes when its cold, when its warm its a bit angry, it just randomly pops and bangs when it feels like it lol
i dont have a VTA dump valve, so popping and such iosnt that regular, but i was driving down the road in mine at i dipped the clutch and revved it to about 5k, and it popped, i did this 4 maybe times and it popped every time, then it stopped doing it compleatly, sumtimes it pops on full throttle changes, sumtimes it pops on light throttle changes, it always pops and rumbles when coming down through the gears
what i found very strange was it pops and rumbles less with a td04 fitted, even just driving around town its less noisey, when the vf23 went back on it started "hockling" like a 80 a day smoker first thing in the morning lol
i noticed a decent power gain when it was fitted but im now at that stage again when it feels like its getting slower
(we have all been there, time to fit a bigger turbo or sumthing)
i dont have a VTA dump valve, so popping and such iosnt that regular, but i was driving down the road in mine at i dipped the clutch and revved it to about 5k, and it popped, i did this 4 maybe times and it popped every time, then it stopped doing it compleatly, sumtimes it pops on full throttle changes, sumtimes it pops on light throttle changes, it always pops and rumbles when coming down through the gears
what i found very strange was it pops and rumbles less with a td04 fitted, even just driving around town its less noisey, when the vf23 went back on it started "hockling" like a 80 a day smoker first thing in the morning lol
i noticed a decent power gain when it was fitted but im now at that stage again when it feels like its getting slower
(we have all been there, time to fit a bigger turbo or sumthing)
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19 September 2004, 10:01 PM
#8
Tried the airbox mod today
Removed the snorkel bit under the wing and the intake bit fixed behind the headlight,
ran a piece of hose from behind the indicator and sealed it around the airbox intake,
The noise was more noticable and it sucked like a prague pro but ive now put it back standard for now untill i can locate the intake hose somwhere its not gonna suck in the water if you hit some good puddles,
Any ideas or pics appreciated,i havnt got the gear to monitor intake temps but as someones already said they were no different to standard ??
Keep ya posted
Removed the snorkel bit under the wing and the intake bit fixed behind the headlight,
ran a piece of hose from behind the indicator and sealed it around the airbox intake,
The noise was more noticable and it sucked like a prague pro but ive now put it back standard for now untill i can locate the intake hose somwhere its not gonna suck in the water if you hit some good puddles,
Any ideas or pics appreciated,i havnt got the gear to monitor intake temps but as someones already said they were no different to standard ??
Keep ya posted
Originally Posted by StickyMicky
i hate the noise mine makes when its cold, when its warm its a bit angry, it just randomly pops and bangs when it feels like it lol
i dont have a VTA dump valve, so popping and such iosnt that regular, but i was driving down the road in mine at i dipped the clutch and revved it to about 5k, and it popped, i did this 4 maybe times and it popped every time, then it stopped doing it compleatly, sumtimes it pops on full throttle changes, sumtimes it pops on light throttle changes, it always pops and rumbles when coming down through the gears
what i found very strange was it pops and rumbles less with a td04 fitted, even just driving around town its less noisey, when the vf23 went back on it started "hockling" like a 80 a day smoker first thing in the morning lol
i noticed a decent power gain when it was fitted but im now at that stage again when it feels like its getting slower (we have all been there, time to fit a bigger turbo or sumthing)
i dont have a VTA dump valve, so popping and such iosnt that regular, but i was driving down the road in mine at i dipped the clutch and revved it to about 5k, and it popped, i did this 4 maybe times and it popped every time, then it stopped doing it compleatly, sumtimes it pops on full throttle changes, sumtimes it pops on light throttle changes, it always pops and rumbles when coming down through the gears
what i found very strange was it pops and rumbles less with a td04 fitted, even just driving around town its less noisey, when the vf23 went back on it started "hockling" like a 80 a day smoker first thing in the morning lol
i noticed a decent power gain when it was fitted but im now at that stage again when it feels like its getting slower
(we have all been there, time to fit a bigger turbo or sumthing)
20 September 2004, 08:54 AM
#9
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I never bothered with an intake hose, simply removed everything, so the air came from in the inner wing - was fine with the panel (NOT so fine once switched to induction kit, as this was feeding from under the bonnet - Mega-hot !)
Micky - I guess the pops are just incorrect mixture, mine did it quite a bit until the remap(s) - excess fuel in the exhaust - maybe thats why it does it more with the vf23 (mixture further out / hotter exhaust) ? I guess reving with the clutch in is a classic 'under burn' case, where lots of fuel is pumped in, but little used (as no real load) ?
Cheers,
Mark
Micky - I guess the pops are just incorrect mixture, mine did it quite a bit until the remap(s) - excess fuel in the exhaust - maybe thats why it does it more with the vf23 (mixture further out / hotter exhaust) ? I guess reving with the clutch in is a classic 'under burn' case, where lots of fuel is pumped in, but little used (as no real load) ?
Cheers,
Mark
20 September 2004, 09:17 AM
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I went on the rollers at Power Engineering on Saturday with my MY97 version 3 STI, completely standard apart from a Scoobysport back box, ie 2 cats still in place! 273 bhp & 246 ftlb torque. They then fitted a Magnex de-cat centre pipe and it ran 288 bhp & 264 ftlb. So a centre pipe added 15 bhp & more importantly 18 ftlb of torque, on it's own, fairly impressive I thought. What your complete de-cat has added, I don't know, but all I would say is, book yourself in for a rolling road session and find out for sure what your running. As an arranged day it only cost £30.
Sooooo many people with Scoobies saying they are 300+ bhp, having read the car was 280PS and then done de-cats, they assume it must be over 300. As PE told me, the car may have been 300PS when it was built, but that was 7 years ago and on 100RON fuel and from what I saw on Sat, very, very few actually are making the 300 mark. The majority there, were between 230 & 260 bhp, only 3 actually got over 300 bhp including one guy who got 505 bhp & 508 ftlb torque!!!!! 2.5 conversion and a few other goodies.
Hope this helps a little.
Sooooo many people with Scoobies saying they are 300+ bhp, having read the car was 280PS and then done de-cats, they assume it must be over 300. As PE told me, the car may have been 300PS when it was built, but that was 7 years ago and on 100RON fuel and from what I saw on Sat, very, very few actually are making the 300 mark. The majority there, were between 230 & 260 bhp, only 3 actually got over 300 bhp including one guy who got 505 bhp & 508 ftlb torque!!!!! 2.5 conversion and a few other goodies.
Hope this helps a little.
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