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I can mention that Marcus is by far the best solderer that I know. If you would see the way my roll bar is soldered, this is just beautiful solder, full 5 stars.
His 510 is just perfectly done, very impressive, the way it is done and the quality of every small details.
I had different special pieces that he did cut for me (he has a plasma/laser cutter), just crazy. He is also excellent on machines.
I highly recommend him.
With the factory ancillaries, the Boxster S 3.2L cars generally won't make any more big power gains past 3.6L displacement. The intake manifold simply is too inefficient, despite different plans that can be used, with bigger throttle bodies.
I have taken these engines to 4.4L, and created an inefficient pig when fitted with factor intake manifolds. Today our developments with all M96/M97 engines are hindered by the intake choices. Thats why I have had to invest in our own full intake systems, made from aluminum for the 4.3 and 4.4L engines, and even some of the R51 and R40 series engines need this.
Size doesn't;t matter if you can't create efficiency.
Well, in French you can say : “Quand tu veux te séparer de ton chien, tu dis qu’il a la rage”.
Or, something like : “When you want to get rid of your dog, you declare that he has rabies”.
What is funny to me, is that in "some places", you can see that engines much older that the M96, (i.e.: some that are air cooled), ..can go well up to 4.4 liters !
Note that in the past, I also heard from some “great specialists” ..that air cooled engines cannot go to high power, ..because there is no way to dissipate the heat created by high power with air !
I think on this one, the Singer machines clearly show that this was a nice “fake news”.
It is also true that in this case, (a great 4.4 liter with an old air cooled engine) ..this was the race shop that developed and built the early SINGER engines ! (even if they had Cosworth” badges !)
..not really a “beginner” !
(Joke ) May be I should look to have an air cooled engine for my Boxster to go to 3.8 liter ?
(This will make me remember of my early 911's ..I had 3 of these air cooled during many years, well before 2 x 996's !)
The issue isn’t that it can’t be done. The issue is the supporting systems won’t support the added displacement. My stock 3.2 already falls off above 5k rpm. Added displacement won’t help that.
Efficiency is all I care about, and we aren't talking "fuel economy". This is why my R51 for the Boxster and Cayman makes more power than a 4.0 in either of those platforms, and does so with 300ccs less displacement.
Do you have a good technical explanation for that ?
High Power has to be made from high torque at high RPM. If displacement is added without changing anything else, the peak torque could go up, but it could also stay unchanged, except it’s now at a lower RPM. If that’s the case, power would actually be lower.
The other problem is that a good engine has a decent operating range of high torque across a wide band of RPM (area under the curve) range. To get that, airflow must be tuned with all components (heads, valve size, port size, port design, intake runner design, exhaust manifold design, muffler design, bore/stroke ratio, camshaft lift, camshaft duration, camshaft overlap, ignition timing). If displacement changes, that tune can change, shrinking the broad window a bit, thereby producing less area under the curve, and less overall power.
The above assumes we have already maxed out the airflow design for peak airflow with all those components listed. If you can re-design and replace all those components, that’s different. I think the M96 engine has limitations here.
The other problem is that if higher displacement yields higher torque at a lower RPM, it might be wise to change all the transmission gear ratios or final drive ratio to be able to take advantage of those improvements. In extreme cases, your 0-60 time with a larger engine with more torque might not improve compared to a smaller one.
Do you have a good technical explanation for that ?
The answers are all here already. It’s about efficiency. Let’s be honest the exhaust system on a Boxster stinks. Long tubes, lots of bends, pre cats, cats and allegedly the intake side isn’t that great either.
If the intake and exhaust are already a restriction, asking them to magically flow more air to feed a larger displacement won’t work.
Start thinking of an engine as a system and not just a bore size.
Thanks, but, ..I have hard time to agree with the above !
First, thinking that :
. From 3.2 to 3.6 gives you 12.5 percent increase.
. From 3.2 to 3.8, you get 18.7 percent increase.
. On a M96 engine, getting a performance filter, a big intake tube, with a 74mm throttle box and a 74 mm plenum, ..you get 18.5% of better intake surface/flow (over the original 68mm diameter).
. On the exhaust side, (I continue to think, that is the major limiter at the 3.2 M96 engine of a 986), any good tuned tubes header will give you an increase of flow much larger than 18%.
OK, porting the heads is most probably a must, but do not get me wrong, if I would go to 101mm Nickies, I will for sure port the heads !
I understand that having the M96 3.6 (on 996’s) being used on racing classes, it makes for sure more number of engines to work on it.
(This while a 3.8 would not be legal and would find no chance on such usage.)
Note that in my case, I just do not care about racing specs (I’m too old to race) and resale potential value (I do not plan to do such mod to generate plus value).
My goal is to have fun on track and have a fun engine on open roads.
Or, very sorry guys, ..but,I’m all but not convinced yet by the "explanations" above and continue to think, that when placing an order at LN, I would still prefer to go for the 101mm instead of the 99mm ones (btw, both Nickies model are the exact same price.)
I could understand that moving from 3.2 to 3.6, (12 percent) may provide a bigger increase of “efficiency” than the "tiny" 3.6 to 3.8 step (5.5%),
but frankly: I have VERY HARD way to understand that these last 200 cc of increase ..will give a negative effect (decrease of power) ! (Yes, I know that power = RPM * torque)
Ah yes the part A adds 10 hp, part B adds 12 hp, part C 8 hp; so my engine must make 30 more hp.
It doesn’t work that way. The throttle body and throttle body plenum are a small fraction of the intake system. The headers are only a fraction of the exhaust system and in a 986 have integrated catalytics.
Your money do as you wish. Clearly any discussion will always be wrong since you are quite certain. If 3.8 is good, then 4.0 must be better so I really think you should go 4.2+. You’ll have to learn about offset ground cranks and small journal bearings but moorr powahs!!!!
Thanks, but, ..I have hard time to agree with the above !
First, thinking that :
. From 3.2 to 3.6 gives you 12.5 percent increase.
. From 3.2 to 3.8, you get 18.7 percent increase.
. On a M96 engine, getting a performance filter, a big intake tube, with a 74mm throttle box and a 74 mm plenum, ..you get 18.5% of better intake surface/flow (over the original 68mm diameter).
. On the exhaust side, (I continue to think, that is the major limiter at the 3.2 M96 engine of a 986), any good tuned tubes header will give you an increase of flow much larger than 18%.
OK, porting the heads is most probably a must, but do not get me wrong, if I would go to 101mm Nickies, I will for sure port the heads !
I understand that having the M96 3.6 (on 996’s) being used on racing classes, it makes for sure more number of engines to work on it.
(This while a 3.8 would not be legal and would find no chance on such usage.)
Note that in my case, I just do not care about racing specs (I’m too old to race) and resale potential value (I do not plan to do such mod to generate plus value).
My goal is to have fun on track and have a fun engine on open roads.
Or, very sorry guys, ..but,I’m all but not convinced yet by the "explanations" above and continue to think, that when placing an order at LN, I would still prefer to go for the 101mm instead of the 99mm ones (btw, both Nickies model are the exact same price.)
I could understand that moving from 3.2 to 3.6, (12 percent) may provide a bigger increase of “efficiency” than the "tiny" 3.6 to 3.8 step (5.5%),
but frankly: I have VERY HARD way to understand that these last 200 cc of increase ..will give a negative effect (decrease of power) ! (Yes, I know that power = RPM * torque)
It doesn’t work like this. I’ve been there, and done that starting 18 years ago with these engines. The very first M96 we developed to big bore was a Boxster. You can install a larger TB and plenum all day long, but the deficiencies with the runners won’t be overcome until you fit a 996 intake. The factory 3.2S runners flow 36% less (on the flowbench) than the 996.1, and thats just one item of the handicapped components.
You can port heads, add big displacement, and etc to a 3.2 based car, but until the ancillaries are changed in a big way, all you’ll do is built an inefficient pig. It’ll make big torque below 5,252 RPM.
Yes, I have built a 3.2S with it’s original engine foundation that made 400 WHP on pump gas, and we did that more than a decade ago. None of the factiry ancillaries were fitted, and it took a year of exhaust development to optimize it.
Keeping it real with first hand, valuable experience here fellas. Share how YOU did it, and what YOUR results were. Oh yeah, I forgot- you don’t have that.
04-06-2019, 10:53 PM
) May be I should look to have an air cooled engine for my Boxster to go to 3.8 liter ?
