Swedish inlet on standard head.
30-03-2008, 09:28 PM
#52
well, its a time issue at the mo,
but i have a few major components, like turbo etc etc, just the engine bits i need to get, but cant till ive had the bore inspected to see id i can stay .5 or not. if not its being linered back to standard.
than its off to martin for longstudding....
but i have a few major components, like turbo etc etc, just the engine bits i need to get, but cant till ive had the bore inspected to see id i can stay .5 or not. if not its being linered back to standard.
than its off to martin for longstudding....
30-03-2008, 09:36 PM
#53
PassionFord Post Troll
The plenum is tappered to create equal air flow into each cylinder. The problem with a straight shape is that air has a momentum as it enters the plenum and this will tend to mean it bypasses the first cylinder and favours the later cylinders.
The tapering of the plenum creates a higher pressure area at the far end when compared to the TB end. The higher pressure discourages some of the air from rushing to the end and the lower pressure area slows it down enough to enter the closer cylinders.
30-03-2008, 09:39 PM
#54
i can only speak from my personal experience with these plenums, and i had a major air flow issue with mine before stu revised my chip, cylinder 1 was very rich, but cylinder 4 was dangerously weak....it cost me an engine as it melted no 4 piston.
its hard to spot as a wideband gives an average, which was fine,
its hard to spot as a wideband gives an average, which was fine,
Last edited by JTECH James; 30-03-2008 at 09:40 PM.
30-03-2008, 09:44 PM
#55
heres the plugs from the engine that died
stu manahed to sort this issue, by playing with the fuelling, but.....there must be an air flow issue for it to need playing with.... the standard one never gave these issues for me.
stu manahed to sort this issue, by playing with the fuelling, but.....there must be an air flow issue for it to need playing with.... the standard one never gave these issues for me.
Last edited by JTECH James; 30-03-2008 at 09:48 PM.
30-03-2008, 09:45 PM
#56
Seeing as the original Swedish plenum is tapered then the cheaper copies should be too if the product is to be sold as a Swedish copy plenum. I buy my Swedish plenums from Sweden as I don't like copies. My original comment was based on a tapered version.
30-03-2008, 09:46 PM
#57
well, its a time issue at the mo,
but i have a few major components, like turbo etc etc, just the engine bits i need to get, but cant till ive had the bore inspected to see id i can stay .5 or not. if not its being linered back to standard.
than its off to martin for longstudding....
but i have a few major components, like turbo etc etc, just the engine bits i need to get, but cant till ive had the bore inspected to see id i can stay .5 or not. if not its being linered back to standard.
than its off to martin for longstudding....
you going central day ?
30-03-2008, 10:35 PM
#63
Norris Motorsport
I don't recommend these types of inlet for two major reasons.
1. Un-uniform air flow to each cylinder
2. Lazy throttle response.
Whilst many will argue one version is better than another, I have tested virtually all types on the market today and none flow uniformly. Some show EGT spreads as wide as 200DegC on full boost which can spell disaster when the engine is mapped on average AFR/EGT alone.
I now advise that all cars being mapped with this stlye plenum should have individual EGT monitoring.
Lastly remember that turbo charged cars running a single throttle body should have a plenum design that allows air to enter in as uniformly central position as possible, otherwise the effect of forced air velocity will have a substantial impact on individual cylinder air flow.
1. Un-uniform air flow to each cylinder
2. Lazy throttle response.
Whilst many will argue one version is better than another, I have tested virtually all types on the market today and none flow uniformly. Some show EGT spreads as wide as 200DegC on full boost which can spell disaster when the engine is mapped on average AFR/EGT alone.
I now advise that all cars being mapped with this stlye plenum should have individual EGT monitoring.
Lastly remember that turbo charged cars running a single throttle body should have a plenum design that allows air to enter in as uniformly central position as possible, otherwise the effect of forced air velocity will have a substantial impact on individual cylinder air flow.
Last edited by Karl; 30-03-2008 at 10:36 PM.
30-03-2008, 10:48 PM
#65
PassionFord Post Whore!!
Thread Starter
What about the Rainbird ones, Im sure I was told somewhere his flow really well??
I could be wrong but Im sure his were mentioned as being good.
I could be wrong but Im sure his were mentioned as being good.
30-03-2008, 10:56 PM
#66
Norris Motorsport
I've refrained from mentioning whose are worse than others, but I would NEVER fit one to any engine of mine. None flow uniformly enough to justify using one.
If you require a plenum to flow 500bhp use an EEC4 item, otherwise use a genuine RS500 item for power beyond 500bhp. (You can add a small spacer to the 500 plenum for extra flow if required without upsetting individual cylinder flow, should your aim be 600bhp+.)
There are other manifolds out there that flow well but are considerably more expensive than those mentioned above.
If you require a plenum to flow 500bhp use an EEC4 item, otherwise use a genuine RS500 item for power beyond 500bhp. (You can add a small spacer to the 500 plenum for extra flow if required without upsetting individual cylinder flow, should your aim be 600bhp+.)
There are other manifolds out there that flow well but are considerably more expensive than those mentioned above.
31-03-2008, 07:57 AM
#74
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Hmmm, well having had 2 of the most respected cos tuners say don't use one I think I won't use one!! Even though it looks good its not worth melting pistons etc to look good. 
31-03-2008, 08:36 AM
#76
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) so I'll stick with the stock item for now.
31-03-2008, 10:34 AM
#77
PassionFord Post Troll
As taken from the R&B website:
"This manifold removes the restrictive elbow, and due to it's unique design, it has been flow tested and at 2 bar of boost there is only a 2% disparity accross the cylinders. This is considerably better than the OE manifold."
Proof that a tapered swedish plenum can work well.
Mikes tapered swedish plenum design has been run on successfully on many big power cars.
"This manifold removes the restrictive elbow, and due to it's unique design, it has been flow tested and at 2 bar of boost there is only a 2% disparity accross the cylinders. This is considerably better than the OE manifold."
Proof that a tapered swedish plenum can work well.
Mikes tapered swedish plenum design has been run on successfully on many big power cars.
31-03-2008, 12:38 PM
#79
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As taken from the R&B website:
"This manifold removes the restrictive elbow, and due to it's unique design, it has been flow tested and at 2 bar of boost there is only a 2% disparity accross the cylinders. This is considerably better than the OE manifold."
Proof that a tapered swedish plenum can work well.
Mikes tapered swedish plenum design has been run on successfully on many big power cars.
"This manifold removes the restrictive elbow, and due to it's unique design, it has been flow tested and at 2 bar of boost there is only a 2% disparity accross the cylinders. This is considerably better than the OE manifold."
Proof that a tapered swedish plenum can work well.
Mikes tapered swedish plenum design has been run on successfully on many big power cars.
.... Flow bench tested, not made in someones back garden 
. Mike, does this provide any useful gains anywhere over an EEC IV plenum up to 550ish bHP? and would it be useful on a 400BHP engine?