Intake side plate spacers..
01-01-2011, 05:21 AM
#1
Rennlist Member
Thread Starter
Intake side plate spacers..
On the fence here...should I? Should I not?
Its not about the cost..im all apart, great time to do it..etc...
But looking at this here chart...
..is the bottom half of the RPM band loss worth the top end gain?
Supporting mods:
Xpipe
89 exhaust
RMB
Its not about the cost..im all apart, great time to do it..etc...
But looking at this here chart...
..is the bottom half of the RPM band loss worth the top end gain?
Supporting mods:
Xpipe
89 exhaust
RMB
01-01-2011, 05:29 AM
#2
Rennlist Member
looks like a trade off for little gain. But, some gain.
Brian had tried them and they gave him more up top too. but the stroker lost lower end with no gains up top at all. this could be only an isolated result due to the larger displacement of my engine
Brian had tried them and they gave him more up top too. but the stroker lost lower end with no gains up top at all. this could be only an isolated result due to the larger displacement of my engine
01-01-2011, 05:46 AM
#3
Rennlist Member
Thread Starter
*nods*
Further eyeballing, looks like it takes a well running S4, and removes the big flappy power increase as well, which is a noticeable kick.
I don think I will do this.
Sure..there are gains. But this isnt an NSX. I dont wanna -have- to drive it at 5000rpm just to feel like I'm starting to get something out of it.
Further eyeballing, looks like it takes a well running S4, and removes the big flappy power increase as well, which is a noticeable kick.
I don think I will do this.
Sure..there are gains. But this isnt an NSX. I dont wanna -have- to drive it at 5000rpm just to feel like I'm starting to get something out of it.
01-01-2011, 09:33 AM
#4
Basic Sponsor
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We sell a lot of them but they are for "Bling" only on a stock motor. We tried to emulate the gains shown by the MS dyno sheet on a number of cars but could not see any measurable gains.
On Modified engines they do assist. In many cases one only is fitted to the drivers side.
I have also seen the spacers fitted that are about 1" wide.
I have them on my car and they look awesome.
Ours are correctly machined to take the stock O rings and don't use superglue like the MS ones.
$160 a set. Includes screws and O rings.
On Modified engines they do assist. In many cases one only is fitted to the drivers side.
I have also seen the spacers fitted that are about 1" wide.
I have them on my car and they look awesome.
Ours are correctly machined to take the stock O rings and don't use superglue like the MS ones.
$160 a set. Includes screws and O rings.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Last edited by ROG100; 01-02-2011 at 11:02 AM.
01-01-2011, 01:09 PM
#6
Rennlist Member
Mine
We sell a lot of them but they are for "Bling" only on a stock motor. We tried to emulate the gains shown by the MS dyno sheet on a number of cars but could not see any measurable gains.
On Modified engines they do assist. In many cases one only is fitted to the drivers side.
I have also seen the spacers fitted that are about 1" wide.
I have them on my car and they look awesome.
Ours are correctly machined to take the stock O rings and don't use superglue like the MS ones.
$160 a set. Includes scres and O rings.
On Modified engines they do assist. In many cases one only is fitted to the drivers side.
I have also seen the spacers fitted that are about 1" wide.
I have them on my car and they look awesome.
Ours are correctly machined to take the stock O rings and don't use superglue like the MS ones.
$160 a set. Includes scres and O rings.
The plan is though to go with an S/C set up in future, so I'm planning ahead.
01-01-2011, 03:17 PM
#7
Rennlist Member
the only things that this mod can do, is increase the volume on the intake plennum sides which alters the Heimholz resonance, and possibly reduces pressure drop accross the inlets of the runners that were "pinched" too close to the stock side plates. temperature change is not a benefit or effect.We sell a lot of them but they are for "Bling" only on a stock motor. We tried to emulate the gains shown by the MS dyno sheet on a number of cars but could not see any measurable gains.
On Modified engines they do assist. In many cases one only is fitted to the drivers side.
I have also seen the spacers fitted that are about 1" wide.
I have them on my car and they look awesome.
Ours are correctly machined to take the stock O rings and don't use superglue like the MS ones.
$160 a set. Includes scres and O rings.
On Modified engines they do assist. In many cases one only is fitted to the drivers side.
I have also seen the spacers fitted that are about 1" wide.
I have them on my car and they look awesome.
Ours are correctly machined to take the stock O rings and don't use superglue like the MS ones.
$160 a set. Includes scres and O rings.
Trending Topics
01-01-2011, 07:28 PM
#8
Drifting
If you are talking about the spacers in the picture below? this is what it says about them on 928 MS
I don't think I will bother with them
Originally Posted by from 928MS page
The Problem: The intake manifold side covers are too close to the ends of the intake runners beneath them, restricting air flow to several cylinders at wide-open throttle. On the left side, the intake bell-mouths for cylinders 5 and 8 are too close to the sides to draw air smoothly from the entire circumference of the bell mouth. On the right side, cylinders 1 and 4 are the most pronounced, but not a s close as on the left side. However, they are located in such a way as to rob and restrict air from cylinders 6 and 7 that are nestled behind them
01-01-2011, 07:36 PM
#9
Rennlist Member
Problem is we dont have any flow bench data for our intake system. we dont know if the flow is restricted due to the plates being close to the runner inlets. if they were, the spacers would help and they dont, really , at least on the 6.5 liter. what can happen is that you are altering the pressure pulse tuning of the intake, which could have some trade offs. however, we know when bolting on the CF intake, 50-75hp can be made on a stroker. Now, if someone with a 5 liter would put on the CF intake, we could learn much about the draw backs of the stock intake on a stock bottomend.
01-01-2011, 07:43 PM
#10
Former Vendor
We've tried them also...and have not been able to measure any increase...on any engine...to this point. I think any "positive results" are from setting full throttle after installation...since you need to remove the throttle assembly to install the spacers.
If you are going to buy a set, to try, do yourself a favor and buy Roger's. They seal much better than the "glue on" version from 928 Motorsports.
If you are going to buy a set, to try, do yourself a favor and buy Roger's. They seal much better than the "glue on" version from 928 Motorsports.
01-01-2011, 07:50 PM
#11
Former Vendor
Problem is we dont have any flow bench data for our intake system. we dont know if the flow is restricted due to the plates being close to the runner inlets. if they were, the spacers would help and they dont, really , at least on the 6.5 liter. what can happen is that you are altering the pressure pulse tuning of the intake, which could have some trade offs. however, we know when bolting on the CF intake, 50-75hp can be made on a stroker. Now, if someone with a 5 liter would put on the CF intake, we could learn much about the draw backs of the stock intake on a stock bottomend.
I've literally got hundreds of flow bench tests on "our" intake systems/heads, all graphed and compared to a huge data base of stock pieces....
01-02-2011, 02:23 AM
#12
Rennlist Member
Happy New Year everyone!
Another chesnut that seems to come around every few months or so. Every heard the mantra YMMV?
My take on this is that perhaps there is some variance in tolerances on different manifold units- perhaps related to batch production [?]. If you have done any sharktuning with John's ST2 kit [I have] then you quickly notice when logging knocks that invariably some cylinders start knocking earlier than others. This suggests to me [at least] uneven flow into cylinders that are [theoretically] equally injected hence some will lean out more in relative terms. Assuming your injectors are clean and equally flowing [mine have been cleaned and bench tested] the logical assumption is that more air flow induces earlier onset of pre-ignition. Relative to a stock mapping, I found that knock is more prevalent around the transition zone [3800 rpm or so] and it seemed to like more enrichment around that point [and lower rpms]. Even so at the point I stopped trying to dial in more advance, I still had a couple of cylinders that were more prone to knocking and just as interesting, a couple that never showed any knock at all, my assumption being that the latter was because they are [relatively speaking] "air starved" thus run a tad richer. Unfortunately I cannot remember cylinder numbers, but they seemed to align with those reportedly more affected by the proximity of the inlet runner to the end plate.
When Porsche designed this intake manifold, I understand it was not designed for top end or any specific rpm point, rather the inlet runners are tuned [individually] to give a more even spread across the rpm range [whatever that range is]. For sure I could not tune out the "more prone" cylinders and simply optimised them best I could with my limited skills guided by some very competent remote advisers.
Several months after completing the sharktuning exercise I purchased a set of these spacers from Carl [his was the first offering I saw posted]. I felt no deleterious effect at low rpm to my S4 motor but the top end felt noticeably livelier. I do not have any dyno figures to prove or disprove anything but I was well pleased with the effect noting that for the price involved I would have been quite happy to remove them if I had experienced no positive impact. Whether the placebo effects kicks in here remains to be seen.
I would have been equally happy to purchase from Roger had I seen his items first. Bottomline is that when Porsche say the 928 S4 produces 316 BHP and whatever peak torque, what they mean is that every example produces that amount and some more than others but they do not guarantee the exact curve each example produces. So, there has to be an explanation as to why some engines are better than others and maybe this feature explains some [not all!] of the differences that logically occur example to example.
The example tested by Carl showd a typical S4 curve, nothing obviously wrong.
As for Carl's kit and sealing, all I can say is that the sealant that he provided with the spacers sticks like nothing I have used before and although a little messy if you are not careful and a little difficult to remove even with petrol, appears to seal really well. I would think using the sealing gasket system provided by Porsche is a more elegant design but then it would need four gaskets instead of two.
Bottom line, if $160 hurts your pocket then do not bother with this mod and stick with what you have. My experience was that my motor felt livelier and smoother after the mod. YMMV! The only downside was that on one of the fuel rails [passenger side I think] I could not fit one of the nuts that holds the fuel rail to the manifold but then I doubt it is going anywhere given everything else that is bolted to it.
Regards
Fred R
Another chesnut that seems to come around every few months or so. Every heard the mantra YMMV?
My take on this is that perhaps there is some variance in tolerances on different manifold units- perhaps related to batch production [?]. If you have done any sharktuning with John's ST2 kit [I have] then you quickly notice when logging knocks that invariably some cylinders start knocking earlier than others. This suggests to me [at least] uneven flow into cylinders that are [theoretically] equally injected hence some will lean out more in relative terms. Assuming your injectors are clean and equally flowing [mine have been cleaned and bench tested] the logical assumption is that more air flow induces earlier onset of pre-ignition. Relative to a stock mapping, I found that knock is more prevalent around the transition zone [3800 rpm or so] and it seemed to like more enrichment around that point [and lower rpms]. Even so at the point I stopped trying to dial in more advance, I still had a couple of cylinders that were more prone to knocking and just as interesting, a couple that never showed any knock at all, my assumption being that the latter was because they are [relatively speaking] "air starved" thus run a tad richer. Unfortunately I cannot remember cylinder numbers, but they seemed to align with those reportedly more affected by the proximity of the inlet runner to the end plate.
When Porsche designed this intake manifold, I understand it was not designed for top end or any specific rpm point, rather the inlet runners are tuned [individually] to give a more even spread across the rpm range [whatever that range is]. For sure I could not tune out the "more prone" cylinders and simply optimised them best I could with my limited skills guided by some very competent remote advisers.
Several months after completing the sharktuning exercise I purchased a set of these spacers from Carl [his was the first offering I saw posted]. I felt no deleterious effect at low rpm to my S4 motor but the top end felt noticeably livelier. I do not have any dyno figures to prove or disprove anything but I was well pleased with the effect noting that for the price involved I would have been quite happy to remove them if I had experienced no positive impact. Whether the placebo effects kicks in here remains to be seen.
I would have been equally happy to purchase from Roger had I seen his items first. Bottomline is that when Porsche say the 928 S4 produces 316 BHP and whatever peak torque, what they mean is that every example produces that amount and some more than others but they do not guarantee the exact curve each example produces. So, there has to be an explanation as to why some engines are better than others and maybe this feature explains some [not all!] of the differences that logically occur example to example.
The example tested by Carl showd a typical S4 curve, nothing obviously wrong.
As for Carl's kit and sealing, all I can say is that the sealant that he provided with the spacers sticks like nothing I have used before and although a little messy if you are not careful and a little difficult to remove even with petrol, appears to seal really well. I would think using the sealing gasket system provided by Porsche is a more elegant design but then it would need four gaskets instead of two.
Bottom line, if $160 hurts your pocket then do not bother with this mod and stick with what you have. My experience was that my motor felt livelier and smoother after the mod. YMMV! The only downside was that on one of the fuel rails [passenger side I think] I could not fit one of the nuts that holds the fuel rail to the manifold but then I doubt it is going anywhere given everything else that is bolted to it.
Regards
Fred R
01-02-2011, 02:38 AM
#13
Happy New Year everyone!
Another chesnut that seems to come around every few months or so. Every heard the mantra YMMV?
My take on this is that perhaps there is some variance in tolerances on different manifold units- perhaps related to batch production [?]. If you have done any sharktuning with John's ST2 kit [I have] then you quickly notice when logging knocks that invariably some cylinders start knocking earlier than others. This suggests to me [at least] uneven flow into cylinders that are [theoretically] equally injected hence some will lean out more in relative terms. Assuming your injectors are clean and equally flowing [mine have been cleaned and bench tested] the logical assumption is that more air flow induces earlier onset of pre-ignition. Relative to a stock mapping, I found that knock is more prevalent around the transition zone [3800 rpm or so] and it seemed to like more enrichment around that point [and lower rpms]. Even so at the point I stopped trying to dial in more advance, I still had a couple of cylinders that were more prone to knocking and just as interesting, a couple that never showed any knock at all, my assumption being that the latter was because they are [relatively speaking] "air starved" thus run a tad richer. Unfortunately I cannot remember cylinder numbers, but they seemed to align with those reportedly more affected by the proximity of the inlet runner to the end plate.
When Porsche designed this intake manifold, I understand it was not designed for top end or any specific rpm point, rather the inlet runners are tuned [individually] to give a more even spread across the rpm range [whatever that range is]. For sure I could not tune out the "more prone" cylinders and simply optimised them best I could with my limited skills guided by some very competent remote advisers.
Several months after completing the sharktuning exercise I purchased a set of these spacers from Carl [his was the first offering I saw posted]. I felt no deleterious effect at low rpm to my S4 motor but the top end felt noticeably livelier. I do not have any dyno figures to prove or disprove anything but I was well pleased with the effect noting that for the price involved I would have been quite happy to remove them if I had experienced no positive impact. Whether the placebo effects kicks in here remains to be seen.
I would have been equally happy to purchase from Roger had I seen his items first. Bottomline is that when Porsche say the 928 S4 produces 316 BHP and whatever peak torque, what they mean is that every example produces that amount and some more than others but they do not guarantee the exact curve each example produces. So, there has to be an explanation as to why some engines are better than others and maybe this feature explains some [not all!] of the differences that logically occur example to example.
The example tested by Carl showd a typical S4 curve, nothing obviously wrong.
As for Carl's kit and sealing, all I can say is that the sealant that he provided with the spacers sticks like nothing I have used before and although a little messy if you are not careful and a little difficult to remove even with petrol, appears to seal really well. I would think using the sealing gasket system provided by Porsche is a more elegant design but then it would need four gaskets instead of two.
Bottom line, if $160 hurts your pocket then do not bother with this mod and stick with what you have. My experience was that my motor felt livelier and smoother after the mod. YMMV! The only downside was that on one of the fuel rails [passenger side I think] I could not fit one of the nuts that holds the fuel rail to the manifold but then I doubt it is going anywhere given everything else that is bolted to it.
Regards
Fred R
Another chesnut that seems to come around every few months or so. Every heard the mantra YMMV?
My take on this is that perhaps there is some variance in tolerances on different manifold units- perhaps related to batch production [?]. If you have done any sharktuning with John's ST2 kit [I have] then you quickly notice when logging knocks that invariably some cylinders start knocking earlier than others. This suggests to me [at least] uneven flow into cylinders that are [theoretically] equally injected hence some will lean out more in relative terms. Assuming your injectors are clean and equally flowing [mine have been cleaned and bench tested] the logical assumption is that more air flow induces earlier onset of pre-ignition. Relative to a stock mapping, I found that knock is more prevalent around the transition zone [3800 rpm or so] and it seemed to like more enrichment around that point [and lower rpms]. Even so at the point I stopped trying to dial in more advance, I still had a couple of cylinders that were more prone to knocking and just as interesting, a couple that never showed any knock at all, my assumption being that the latter was because they are [relatively speaking] "air starved" thus run a tad richer. Unfortunately I cannot remember cylinder numbers, but they seemed to align with those reportedly more affected by the proximity of the inlet runner to the end plate.
When Porsche designed this intake manifold, I understand it was not designed for top end or any specific rpm point, rather the inlet runners are tuned [individually] to give a more even spread across the rpm range [whatever that range is]. For sure I could not tune out the "more prone" cylinders and simply optimised them best I could with my limited skills guided by some very competent remote advisers.
Several months after completing the sharktuning exercise I purchased a set of these spacers from Carl [his was the first offering I saw posted]. I felt no deleterious effect at low rpm to my S4 motor but the top end felt noticeably livelier. I do not have any dyno figures to prove or disprove anything but I was well pleased with the effect noting that for the price involved I would have been quite happy to remove them if I had experienced no positive impact. Whether the placebo effects kicks in here remains to be seen.
I would have been equally happy to purchase from Roger had I seen his items first. Bottomline is that when Porsche say the 928 S4 produces 316 BHP and whatever peak torque, what they mean is that every example produces that amount and some more than others but they do not guarantee the exact curve each example produces. So, there has to be an explanation as to why some engines are better than others and maybe this feature explains some [not all!] of the differences that logically occur example to example.
The example tested by Carl showd a typical S4 curve, nothing obviously wrong.
As for Carl's kit and sealing, all I can say is that the sealant that he provided with the spacers sticks like nothing I have used before and although a little messy if you are not careful and a little difficult to remove even with petrol, appears to seal really well. I would think using the sealing gasket system provided by Porsche is a more elegant design but then it would need four gaskets instead of two.
Bottom line, if $160 hurts your pocket then do not bother with this mod and stick with what you have. My experience was that my motor felt livelier and smoother after the mod. YMMV! The only downside was that on one of the fuel rails [passenger side I think] I could not fit one of the nuts that holds the fuel rail to the manifold but then I doubt it is going anywhere given everything else that is bolted to it.
Regards
Fred R
https://rennlist.com/forums/928-foru...stall-tip.html
01-02-2011, 03:40 AM
#14
Rennlist Member
Brain,
Thanks for the input but on my model there was no room to stick anything on the nut in question- Could not even get the nut in to finger tighten it yet alone tension it with anything.
Best wishes
Fred
Thanks for the input but on my model there was no room to stick anything on the nut in question- Could not even get the nut in to finger tighten it yet alone tension it with anything.
Best wishes
Fred
01-02-2011, 04:32 AM
#15
Rennlist Member
Point is, if we have flow numbers for the manifold, lets post them with and without the spacers. it would be easier than dyno runs. 
my guess based on my dyno runs, would be that there wouldnt be any difference. however, the resonance characteristics would have to be dyno tested to check. I posted my dyno runs. I gained nothing, but lost about 50ft-lbs of torque in an area that was very important.
Its really too bad we dont have access to another intake system like the CF intake. I wonder how it would help the stock S4. I think my next project will be adapting the plastic large runner intake of the BMW M5 V8 to our engine.
Fred, the intake was designed for a broad performance range. the flappy is an adder that added a big torque at the street RPMs. without it, you lose all the low end torque, but the upper end is not effected as open or close, it seems to make no difference.
my guess based on my dyno runs, would be that there wouldnt be any difference. however, the resonance characteristics would have to be dyno tested to check. I posted my dyno runs. I gained nothing, but lost about 50ft-lbs of torque in an area that was very important.Its really too bad we dont have access to another intake system like the CF intake. I wonder how it would help the stock S4. I think my next project will be adapting the plastic large runner intake of the BMW M5 V8 to our engine.
Fred, the intake was designed for a broad performance range. the flappy is an adder that added a big torque at the street RPMs. without it, you lose all the low end torque, but the upper end is not effected as open or close, it seems to make no difference.