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YOUR RESEARCHMA121 3.4 litre engine - can Boxster S power be upgraded to 911 power?
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Replace intake and exhaust sides of the engine knowing it
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Suggestion
When designing the engine for the Boxster/Cayman models Porsche would of probably had a target power level and intentionally changed the intake and exhaust sides of the engine knowing it.
MA121 3.4 litre engine - can Boxster S power be upgraded to 911 power?
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Leading evidence: 'Replace intake and exhaust sides of the engine knowing it' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace intake and exhaust sides of the engine knowing it' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Replace intake and exhaust sides of the engine knowing it
No successful repair reported for this finding.
0
Reported fixes
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Unsuccessful attempts
1
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Suggestion
When designing the engine for the Boxster/Cayman models Porsche would of probably had a target power level and intentionally changed the intake and exhaust sides of the engine knowing it.
MA121 3.4 litre engine - can Boxster S power be upgraded to 911 power?
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My understanding is that the MA121 3.4 direct fuel injected engine fitted to Boxster / Cayman from 987.2 / 981 from 2009-2016 is fundamentally the same engine as that fitted to the 911 of the same period.
I am sure I am not the first person to ask, is there a relatively straight forward chip / tune solution to bridge the large ( but artificial) power gap between the two instances of the same engine.
Anyone been down this route?
check out "Roys Tunes" , he comes to your place ,well priced. He tuned my 987.1 2.7L . Makes a massive difference. My understanding is that you get even better results /more gain on the 3.4 L engine. Cheers.
From what I've seen the stock gains aren't too impressive, Cobb have a tune for it and you can see the gains they have on their stock tunes here
https://www.cobbtuning.com/products/accessport/accessport-for-porsche-987-2-cayman-boxster-997-2-carrera
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https://www.cobbtuning.com/products/accessport/accessport-for-porsche-981-cayman-boxster-991-1-carrera
An Intake plenum and headers seem to be the best ways to extract power.
When designing the engine for the Boxster/Cayman models Porsche would of probably had a target power level and intentionally changed the intake and exhaust sides of the engine knowing it.
Rego - thanks for the link. Yes looks like no ‘quick wins’.
I accept that matching the 911 hp may be restricted by hardware like valve size, but it surprises me it isn’t fairly straight forward to take a Boxster S and replicate the Cayman S or Spyder power. I can’t recall reading anything suggesting that there are any hardware changes that the higher HP would be attributable.
Yes all the research that i have done on the 991and 987.2 Engine suggests that they are the same except for the different exhaust setup on the Cayman and a higher state of tune for the 991.
Cobb don't say what they tested on, nor do they differentiate between the Boxster and Cayman which I thinks makes sense as I think its exactly the same gear with an artificial bump for the Cayman.
Even stock the difference is 7kw which is around a 3% gain between a Boxster S and Spyder/Cayman S model which is not much and Cobb was able to get an extra 3% on 98 over what their baseline.
Question is do you need more power? The cornering capacity of these cars is enormous and I have trouble containing myself to double the speed limit in the base Boxster I own now on most roads and I think this car is going to go extremely well on the track with a set of coilovers and semis.
Good call.
Easy to get seduced with stacking on the HP but I guess these cars are all about the theatre, mid corner feedback and carving up mountain passes.
The 987.2 Cayman R, the sister car to the 987.2 Spyder has got larger diameter tubing in the exhaust to give it more hp - 55mm vs 48mm in the Spyder and all 987 Boxster/Cayman models.
I agree - the better mod to get for any of the Boxster and Cayman models is a mechanical LSD over a tune. An LSD allows you to power through corners easily (as you are not fighting with the car round corners). This is the first thing I noticed when I got my 987.2 Spyder which has LSD as standard vs my 2008 987.1 Boxster S.
This is a source reference. Confirm exact model applicability in the original material.
