What restricts a 2.5 revving past 5500rpm ?
27 May 2008, 08:49 PM
#38
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The 20g is front entry.... yes
I originally had a phase 1 manifold, hence a 90' inlet Samco hose....
It is now having/had the inlet raised..... with a inlet conversion..... so the inlet runs under the inlet manifold...
SWEET !!
(How many times did I mention inlet
)
I originally had a phase 1 manifold, hence a 90' inlet Samco hose....
It is now having/had the inlet raised..... with a inlet conversion..... so the inlet runs under the inlet manifold...
SWEET !!
(How many times did I mention inlet
)
27 May 2008, 09:46 PM
#40
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It goes up to about 7200rpm (should be 7500rpm but i've got something limiting the revs even though the limiter is set to 7500 in the ecu
) at which point it is still pulling very hard.
29 May 2008, 12:39 PM
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to summarise
2.5 engine
V3 heads
Inlet manifold raised
AF20g
Tubular Headers
3" Exhaust
Simtek
Since being built it has always run out of puff at 5500rpm
The Gentleman that is currently dealing with my car has provided further info:
It drops over 100 HP as it goes past 5500 rpm
It also jumps up .2 - .3 BAR boost
Rev limit is 6800 (ECU set)
I will summarise the Suggestions/comments so far:
- Bigger Turbo
Surely the 20g pulls through/past 5500 rpm on a 2.5 ?
- Upgrade heads and Valvetrain
Is this essential - are there others out there with non modified heads on a 2.5 and can rev through 5500 rpm ?
- It's not the Heads it the Turbo that Dictates the power band
How correct is this?
-Samco inlet pie
It has been checked for leaks and collapsing pipes
I appreciate all the responese so far !!
V3 heads
Inlet manifold raised
AF20g
Tubular Headers
3" Exhaust
Simtek
Since being built it has always run out of puff at 5500rpm
The Gentleman that is currently dealing with my car has provided further info:
It drops over 100 HP as it goes past 5500 rpm
It also jumps up .2 - .3 BAR boost
Rev limit is 6800 (ECU set)
I will summarise the Suggestions/comments so far:
- Bigger Turbo
Surely the 20g pulls through/past 5500 rpm on a 2.5 ?
- Upgrade heads and Valvetrain
Is this essential - are there others out there with non modified heads on a 2.5 and can rev through 5500 rpm ?
- It's not the Heads it the Turbo that Dictates the power band
How correct is this?
-Samco inlet pie
It has been checked for leaks and collapsing pipes
I appreciate all the responese so far !!
29 May 2008, 09:27 PM
#49
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i would not think so either, but my mates car is refusing to make the power, its just came back from the scoobyclinic and they have looked over it, fitted a new ecu (apexi had went corrupt) mapped it, fixed a few other problems and RR`d it again for him and it just wont make anything decent (for its rather large spec) we suspect the turbo is ****e to be honest!
its running about 350/350
this is his engine spec (not sure how up to date it is)
he uses this bbs, but i wont name him as he might not want to "get involved"
will show him the thread tho.....
its running about 350/350
this is his engine spec (not sure how up to date it is)
Modification Rating Cost Install Created Updated
APS dump vavle 10 30 0 Mon Oct 16, 2006 17:16 Mon Oct 16, 2006 17:16
Autronic Ecu 10 0 0 Fri May 16, 2008 22:09 Fri May 16, 2008 22:09
Blitz SUS Induction kit 0 80 0 Wed Jan 03, 2007 17:37 Tue Mar 27, 2007 22:01
Blue Chrome powder coated Intercooler pipes 0 30 0 Mon Dec 18, 2006 18:39 Tue Mar 27, 2007 22:02
blue silcone washer jet pipes 0 0 0 Wed Jan 03, 2007 17:43 Wed Jan 03, 2007 17:43
Blue silicone boost pipes 0 0 0 Wed Jan 03, 2007 17:49 Wed Jan 03, 2007 17:49
Denso 550cc injectors 0 250 0 Mon Oct 16, 2006 16:32 Mon Oct 16, 2006 16:32
earthing kit 10 30 0 Mon Oct 16, 2006 16:39 Mon Oct 16, 2006 16:39
Forge header tank 10 100 0 Mon Dec 04, 2006 17:01 Tue Mar 27, 2007 22:02
Hybrid FMIC 10 450 0 Mon Oct 16, 2006 16:32 Mon Oct 16, 2006 16:32
Magnecor plug leads 10 100 0 Mon Dec 04, 2006 17:00 Tue Mar 27, 2007 22:03
Magnex Headers 10 500 0 Mon Dec 04, 2006 16:49 Tue Mar 27, 2007 22:03
Magnex Up pipe 0 0 0 Wed Jan 03, 2007 17:52 Wed Jan 03, 2007 17:52
Mahle forged pistons 0 0 0 Mon Dec 04, 2006 16:51 Mon Dec 04, 2006 16:51
Ported heads 0 200 0 Mon Dec 04, 2006 16:58 Tue Mar 27, 2007 22:04
powder coated alternator cover 0 5 0 Wed Jan 03, 2007 17:44 Tue Mar 27, 2007 22:05
powder coated inlet manifold 0 30 0 Mon Dec 04, 2006 16:53 Tue Mar 27, 2007 22:22
Radiator fan relocated 0 0 0 Wed Jan 03, 2007 17:48 Wed Jan 03, 2007 17:48
Revolution 3" Down pipe 10 0 0 Wed Jan 03, 2007 17:46 Wed Jan 03, 2007 17:46
Revolution 3" exhaust system 10 300 0 Mon Oct 16, 2006 16:34 Tue Mar 27, 2007 22:22
Roger Clark Lightened pulleys 10 250 0 Mon Dec 04, 2006 16:50 Tue Mar 27, 2007 22:23
Samco coolant hoses 10 120 0 Mon Dec 04, 2006 16:52 Tue Mar 27, 2007 22:24
Samco inlet pipe 10 165 0 Mon Oct 16, 2006 17:07 Tue Mar 27, 2007 22:25
Spec R fusebox cover 0 0 0 Wed Jan 03, 2007 17:47 Wed Jan 03, 2007 17:47
STi 7 Short motor 0 1000 0 Mon Dec 18, 2006 18:36 Tue Mar 27, 2007 22:04
Sti 9 Crank and rods 0 0 0 Mon Dec 04, 2006 16:51 Fri May 16, 2008 22:08
Sti oil cap 0 0 0 Wed Jan 03, 2007 17:52 Wed Jan 03, 2007 17:52
Sx fuel pressure regulator 10 0 0 Mon Oct 16, 2006 16:36 Mon Oct 16, 2006 16:36
TDo5/o6 turbo 0 650 0 Mon Dec 04, 2006 16:49 Tue Mar 27, 2007 22:25
Tein Bonnet Lifters 0 70 0 Mon Dec 18, 2006 18:41 Fri May 16, 2008 22:07
walbro fuel pump
APS dump vavle 10 30 0 Mon Oct 16, 2006 17:16 Mon Oct 16, 2006 17:16
Autronic Ecu 10 0 0 Fri May 16, 2008 22:09 Fri May 16, 2008 22:09
Blitz SUS Induction kit 0 80 0 Wed Jan 03, 2007 17:37 Tue Mar 27, 2007 22:01
Blue Chrome powder coated Intercooler pipes 0 30 0 Mon Dec 18, 2006 18:39 Tue Mar 27, 2007 22:02
blue silcone washer jet pipes 0 0 0 Wed Jan 03, 2007 17:43 Wed Jan 03, 2007 17:43
Blue silicone boost pipes 0 0 0 Wed Jan 03, 2007 17:49 Wed Jan 03, 2007 17:49
Denso 550cc injectors 0 250 0 Mon Oct 16, 2006 16:32 Mon Oct 16, 2006 16:32
earthing kit 10 30 0 Mon Oct 16, 2006 16:39 Mon Oct 16, 2006 16:39
Forge header tank 10 100 0 Mon Dec 04, 2006 17:01 Tue Mar 27, 2007 22:02
Hybrid FMIC 10 450 0 Mon Oct 16, 2006 16:32 Mon Oct 16, 2006 16:32
Magnecor plug leads 10 100 0 Mon Dec 04, 2006 17:00 Tue Mar 27, 2007 22:03
Magnex Headers 10 500 0 Mon Dec 04, 2006 16:49 Tue Mar 27, 2007 22:03
Magnex Up pipe 0 0 0 Wed Jan 03, 2007 17:52 Wed Jan 03, 2007 17:52
Mahle forged pistons 0 0 0 Mon Dec 04, 2006 16:51 Mon Dec 04, 2006 16:51
Ported heads 0 200 0 Mon Dec 04, 2006 16:58 Tue Mar 27, 2007 22:04
powder coated alternator cover 0 5 0 Wed Jan 03, 2007 17:44 Tue Mar 27, 2007 22:05
powder coated inlet manifold 0 30 0 Mon Dec 04, 2006 16:53 Tue Mar 27, 2007 22:22
Radiator fan relocated 0 0 0 Wed Jan 03, 2007 17:48 Wed Jan 03, 2007 17:48
Revolution 3" Down pipe 10 0 0 Wed Jan 03, 2007 17:46 Wed Jan 03, 2007 17:46
Revolution 3" exhaust system 10 300 0 Mon Oct 16, 2006 16:34 Tue Mar 27, 2007 22:22
Roger Clark Lightened pulleys 10 250 0 Mon Dec 04, 2006 16:50 Tue Mar 27, 2007 22:23
Samco coolant hoses 10 120 0 Mon Dec 04, 2006 16:52 Tue Mar 27, 2007 22:24
Samco inlet pipe 10 165 0 Mon Oct 16, 2006 17:07 Tue Mar 27, 2007 22:25
Spec R fusebox cover 0 0 0 Wed Jan 03, 2007 17:47 Wed Jan 03, 2007 17:47
STi 7 Short motor 0 1000 0 Mon Dec 18, 2006 18:36 Tue Mar 27, 2007 22:04
Sti 9 Crank and rods 0 0 0 Mon Dec 04, 2006 16:51 Fri May 16, 2008 22:08
Sti oil cap 0 0 0 Wed Jan 03, 2007 17:52 Wed Jan 03, 2007 17:52
Sx fuel pressure regulator 10 0 0 Mon Oct 16, 2006 16:36 Mon Oct 16, 2006 16:36
TDo5/o6 turbo 0 650 0 Mon Dec 04, 2006 16:49 Tue Mar 27, 2007 22:25
Tein Bonnet Lifters 0 70 0 Mon Dec 18, 2006 18:41 Fri May 16, 2008 22:07
walbro fuel pump
will show him the thread tho.....
Last edited by StickyMicky; 29 May 2008 at 09:32 PM.
29 May 2008, 10:09 PM
#50
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If anyone suspects they have an issue with one of my turbos they are welcome to send it back for checking out free of charge, they are all under warranty for a year anyway.
If the turbo inlet sucks shut then the turbo will overspeed due to the loading being removed from the compressor, this has been known to cause the compressor wheel to pick up on the housing and create excess clearance.
The same overspeed issue can occur if the wastegate has been adjusted to tightly closed, this applies to all turbos, the VF series usually fail completely as the compressor wheel falls apart where the tougher TD series MHI turbos just run less efficiently.
Andy
If the turbo inlet sucks shut then the turbo will overspeed due to the loading being removed from the compressor, this has been known to cause the compressor wheel to pick up on the housing and create excess clearance.
The same overspeed issue can occur if the wastegate has been adjusted to tightly closed, this applies to all turbos, the VF series usually fail completely as the compressor wheel falls apart where the tougher TD series MHI turbos just run less efficiently.
Andy
30 May 2008, 04:38 PM
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As far as I'm aware if you have a standard 2.5ltr crank in your engine it has a longer stroke than the 2.0ltr. Larger strokes increase the crankshaft's leverage, which means you have the potential for more torque. But smaller stroke crankshafts such as the 2.0ltr version run to high rpms and are generally easier on the conrods.
If you want a higher reving engine use an sti 8 or such 2.0ltr crankshaft.
If you want a higher reving engine use an sti 8 or such 2.0ltr crankshaft.
30 May 2008, 08:02 PM
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had a chat with another mate today regards my 1st mates problems and it seams a "middleman" was involved in the purchase that i was not told about.
mates turbo was bought from somebody else who claims the turbo came/was ordered from andy, but its possible it did not
shame
mates turbo was bought from somebody else who claims the turbo came/was ordered from andy, but its possible it did not
shame
01 June 2008, 09:42 PM
#53
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how about the version 3 heads never being fitted. at engine build, andmaybe just maybe they are version 1 heads, would this explain the power loss.
cheers mark
p.s maybe you should get rid and buy a robin reliant. like dell boy
cheers mark
p.s maybe you should get rid and buy a robin reliant. like dell boy
02 June 2008, 10:01 AM
#54
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The loss of 100bhp so fast means it cannot be...
1/ Valvetrain unless there is s defect leading to valvefloat etc, the stock valvetrain should be good for a lot more than 5,500rpm, trying to figure if valve float would lead to an increase in the boost 'seen'
2/ Head porting, for bhp to drop that fast it can't be head porting, it can flow enough at 5,400 why not at 5,700, makes no sense
3/ Intake sucking closed would drop boost not increase it
Ideally you need lamda as well, as on a simtek if there is an airflow restriction but no change in boost it will go very rich (Map based not MAF), losing you yet more power than the original restriction would have done.
Other option is just bad mapping with it going so rich it looses power, I saw this once, at over 6,300rpm the car went so rich it felt just like it had hit a rev limiter, being unable to get past 6,500rpm even in first, no more than 6,300 in fourth, power plummited just like yours.
Simon
1/ Valvetrain unless there is s defect leading to valvefloat etc, the stock valvetrain should be good for a lot more than 5,500rpm, trying to figure if valve float would lead to an increase in the boost 'seen'
2/ Head porting, for bhp to drop that fast it can't be head porting, it can flow enough at 5,400 why not at 5,700, makes no sense
3/ Intake sucking closed would drop boost not increase it
Ideally you need lamda as well, as on a simtek if there is an airflow restriction but no change in boost it will go very rich (Map based not MAF), losing you yet more power than the original restriction would have done.
Other option is just bad mapping with it going so rich it looses power, I saw this once, at over 6,300rpm the car went so rich it felt just like it had hit a rev limiter, being unable to get past 6,500rpm even in first, no more than 6,300 in fourth, power plummited just like yours.
Simon
Last edited by The rookie; 02 June 2008 at 10:06 AM.
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