964 engine upgrades
#16
Instructor
Join Date: Feb 2005
Location: Raleigh, NC
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I've always been told that the best way to get your car to go faster was to tighten up the loose nut behind the steering wheel. Performance driving lessons will work wonders - I'm still trying to convince my wife that a few DE days will be a smart investment. ;-)
As stated - small-buck mods won't show dramatic increases in performance... some even rely on synergestic effect to be optimal (like intake, exhaust and ECU) - Porsche squeezed out a LOT with what they had in every given model.
Forced induction seems to be the most significant addition, but many harken to the muscle car axiom: "there's no replacement for displacement."
If money were really no object, I would simply go get a CarreraGT - done.
I'd rather spend time driving the car than having it in the shop getting it tweaked and tuned all the time.
As stated - small-buck mods won't show dramatic increases in performance... some even rely on synergestic effect to be optimal (like intake, exhaust and ECU) - Porsche squeezed out a LOT with what they had in every given model.
Forced induction seems to be the most significant addition, but many harken to the muscle car axiom: "there's no replacement for displacement."
If money were really no object, I would simply go get a CarreraGT - done.
I'd rather spend time driving the car than having it in the shop getting it tweaked and tuned all the time.
#17
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Originally Posted by Geoffrey
If it were me, and this was a street car, I would rebuild the engine to 3.6l spec ensuring I had exactly 11.3:1 compression, not the 10.5-10.7 they normally are. I'd service the heads and port them just enough to clean up the flow, do a very nice multi radius valve job, install a set of custom camshafts matched to the flow of the heads. I'd use a plastic 3.6 manifold (if found economically), remove the cat (or install 100 cell cats), and a use a free flowing exhaust system. I'd install the RS lightweight clutch/flywheel assembly and I'd either reprogram the original ECU or replace with a MoTeC ECU.
How do you feel about replacing the plastic 3.6 manifold with 6x48mm Independent Throttle Bodies? Putting the tag aside, what kind of power gain would you estimate with the engine you described above?
Thanks,
Jyrki
#18
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Sorry to come in from the 993 forum, but if you have a look at my thread, "engine uprade 993" you will see that with a set of heads, some cams, new cats and a remap 360 hp with heaps of torque is easily reached. The car is used as an every day road car and is very drivable. Love it. All of this will work with the 964 base engine, but you may need to go for MOTEC as well. In the UK you can fit a cat bypass and save the cost of new cats on a 964.
If you need more power 415 hp is possible NA.
The NA conversions are in keeping with the character of the car, and there are no messy installations to content with.
I guess that i am a fan.
If you need more power 415 hp is possible NA.
The NA conversions are in keeping with the character of the car, and there are no messy installations to content with.
I guess that i am a fan.
#19
Nordschleife Master
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I have several 964 Cup cars that are pushing 325hp in true blueprinted stock form, no cats, no mufflers with the stock cup ECU and last 3 years of track usage and drive like street cars. I think performance engines have an undeserved reputation for being hard to drive and only good at WOT. I will guarentee that my 3.8l full racing engine will start by pushing the button from OUTSIDE the car COLD, will idle well, and will drive at low speeds fine. It is about the programming. You cannot do this with a carburated engine, but with EFI you can if you take the time to properly do it.
As any performance junky knows, the power lies within the ability to flow air through the engine, so I generally concentrate on the head/cam combination with intake and exhaust improvements. This is the main reason I chose the 9M heads for my engine. So, in my opinion, the bottleneck is the heads/cams/intake in the 964 engine. The ports, valves, and valve job leaves a lot on the table to improve upon.
I like individual throttle bodies because of the throttle response you have and 48mm is probably just about ideal for this application. Be aware that not all ITBs are created equal and you'd want to do research to find which ones work for you.
I think it is possible to get 340-350hp out of a 3.6l engine on 93 octane fuel and still be streetable (less than 7800rpm). Check with Colin at 9M as I don't really know since most of the N/A stuff I've done has either been stock class racing engines (3.6l) or GT racing engines at 3.8l.
FWIW, the 3.8 Mahle pistons aren't all they are cracked up to be. They are extremely heavy, have deaxised wrist pins which hurt 3 of the 6 cylinders and are not optimized for the heads. I'm only using them due to a lack of alternatives (won't use JE). Until Colin makes a good 102mm replacement piston (hopefully later this year), I'm stuck with the Mahle 102.
As any performance junky knows, the power lies within the ability to flow air through the engine, so I generally concentrate on the head/cam combination with intake and exhaust improvements. This is the main reason I chose the 9M heads for my engine. So, in my opinion, the bottleneck is the heads/cams/intake in the 964 engine. The ports, valves, and valve job leaves a lot on the table to improve upon.
I like individual throttle bodies because of the throttle response you have and 48mm is probably just about ideal for this application. Be aware that not all ITBs are created equal and you'd want to do research to find which ones work for you.
I think it is possible to get 340-350hp out of a 3.6l engine on 93 octane fuel and still be streetable (less than 7800rpm). Check with Colin at 9M as I don't really know since most of the N/A stuff I've done has either been stock class racing engines (3.6l) or GT racing engines at 3.8l.
FWIW, the 3.8 Mahle pistons aren't all they are cracked up to be. They are extremely heavy, have deaxised wrist pins which hurt 3 of the 6 cylinders and are not optimized for the heads. I'm only using them due to a lack of alternatives (won't use JE). Until Colin makes a good 102mm replacement piston (hopefully later this year), I'm stuck with the Mahle 102.
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cme41 (09-26-2019)
#20
Burning Brakes
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As Geoffrey says the 3.8 coversion is not a cost effective bang for buck conversion on it's own.
Much better to forget the extra 200ccs and go the Motec and cams route as advocated by 9M.
To get 340 fwhp and remain emissions legal in the US might be tricky (not sure if the 100 cell cats would flow sufficiently well ) suggest you ask Colin.
Much better to forget the extra 200ccs and go the Motec and cams route as advocated by 9M.
To get 340 fwhp and remain emissions legal in the US might be tricky (not sure if the 100 cell cats would flow sufficiently well ) suggest you ask Colin.
#21
Burning Brakes
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tighten up the gear ratios especially for a street car so that you don't have to rev it to redline to stay in the power band. this enables you to have fun at 75 to 80 percent engine effort.
on a stock C2 the 1'st to 2nd and 2nd to 3rd gaps are way to wide.
on a stock C2 the 1'st to 2nd and 2nd to 3rd gaps are way to wide.
#23
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Ok, here is the deal, I spent over 10k on the engine for my SC, I posted here several times as I was researching my options on that car. The funny thing about it is that everyone seemed to think the CIS was limiting and so much more could be done with the motronic... The 964 is new to me, I am looking for the options available, and there doesn't seem like much but for the usual - exhaust, chip, and intake. So I am curious of the details from those who tried different things. I learned I could essentially have a 3.6 in my SC if I put in big p/c's, 964 cams and changed the crank, etc.... I just wonder what I have to play with now.
What cams?? I put 964 cams in the SC. As for the ECU, re-map, or chip, and if so what company is most recommended or not. I have seen something about the european RS ecu but have not been able to find anything about them. I notice chips are very inexpensive for this car compared to the SC, Boxster, and 996? What are peoples expiriences?
What is hot film AFM?
As for the valve springs, from a 993??
Carbs are out, pump gas is best, longevity is really good. I track my cars but I am not GT3 class competetive, mainly I am just not happy unless I can fool with the things, see what I can do. I'm a gear head.
What cams?? I put 964 cams in the SC. As for the ECU, re-map, or chip, and if so what company is most recommended or not. I have seen something about the european RS ecu but have not been able to find anything about them. I notice chips are very inexpensive for this car compared to the SC, Boxster, and 996? What are peoples expiriences?
What is hot film AFM?
As for the valve springs, from a 993??
Carbs are out, pump gas is best, longevity is really good. I track my cars but I am not GT3 class competetive, mainly I am just not happy unless I can fool with the things, see what I can do. I'm a gear head.
#25
Burning Brakes
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Originally Posted by llthomas
What is hot film AFM?
#26
Rennlist Member
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The 3.6 motor that Geoffrey described is basically what is in my car. No motec. I am new to 911's but everyone says that it is fast? Does out run friends early 964 turbo, whatever that means.
Idles like a pack of Harleys and always draws attention. Probably the most fun car I have ever owned. I can endorse this engine set up for seat of the pants excitement.
Steve
Idles like a pack of Harleys and always draws attention. Probably the most fun car I have ever owned. I can endorse this engine set up for seat of the pants excitement.
Steve
#27
Drifting
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The question was "if you had the money" and I think 3,8, cams and Motec is a way to go if you want maxium power. Superchargers and turbos aren't legal in Sweden (if not stock of coruse). But everything connected to horsepower are ridiculously epxensive.
In the real world I won't spend any money on the engine. there is much more to gain from suspension, weight, tires, brakes, the driver and all of this will get you more value than " buying" 30-50 Hp that you won't feel after 3 weeks.
In the real world I won't spend any money on the engine. there is much more to gain from suspension, weight, tires, brakes, the driver and all of this will get you more value than " buying" 30-50 Hp that you won't feel after 3 weeks.