Prospective 981 GT4 Owners Discussion Forum Vol 2
Discussion
Porsche911R said:
no that's a hugh load of parts called the x51 kit and about £12k
Kit consists of
• Cylinder heads with flow-optimized intake and exhaust ports
• Intake Manifold & Throttle Body - Increases inlet size from 76 mm to 82 mm
• X51 Headers - larger cross-section and optimized flow behavior
• Carbon Fiber Airbox with two intake channels
• Modified maps for the DME control unit
• Sport Exhaust with Chrome Tips & Dash Switch - (Optional)
• Third Radiator Kit (for manual transmission cars)
• Increased Engine speed
The X51 in the 997.2 which is in the 997.2 gts and could be added to the 997.2s at I believe a cost of £8k and gave 408hp which is 8hp more than the 991s and 22hp less than an x51 991gts all from same engine!Kit consists of
• Cylinder heads with flow-optimized intake and exhaust ports
• Intake Manifold & Throttle Body - Increases inlet size from 76 mm to 82 mm
• X51 Headers - larger cross-section and optimized flow behavior
• Carbon Fiber Airbox with two intake channels
• Modified maps for the DME control unit
• Sport Exhaust with Chrome Tips & Dash Switch - (Optional)
• Third Radiator Kit (for manual transmission cars)
• Increased Engine speed
Edited by Porsche911R on Thursday 16th June 14:02
Apart from the ported cylinder head the rest is bolt on ie manifolds,headers,intake and throttle body plus remap circa £4-5k.
the gt4 also already has third radiator and sports exhaust.
yes the x51 was £8,066 I have the 997.2 price list book!
"power upgrade to 300kw(408 hp). Includes modified cylinder heads,air filter housing with cover in authentic carbon fibre,newly developed variable resonance intake manifold with 6 switchable valves,sports exhaust system with specially designed twin dual-tube tailpipes,and optimised electronics"
no mention of third radiator although this may have been the case for the 997.1 X51 powerkit
"power upgrade to 300kw(408 hp). Includes modified cylinder heads,air filter housing with cover in authentic carbon fibre,newly developed variable resonance intake manifold with 6 switchable valves,sports exhaust system with specially designed twin dual-tube tailpipes,and optimised electronics"
no mention of third radiator although this may have been the case for the 997.1 X51 powerkit
GT4P said:
jackwood said:
For some reason my 997 GTS engine feels far far freer revving across the full range (not just top end) than the GT4 does.
That's because it has not been restricted ( ie no smaller TB etc) and therefore breaths better!Trev450 said:
Has anyone actually replaced the GT4 TB with a larger one yet to gauge the difference?
I am sure some one out there has , I would like to see dyno testing before and after! There is a kit that includes TB, plenum, filter and remap for a couple of K and you can spec sports / race headers for a few more.GT4P said:
Interesting:"Power gains with the GT4 Competition Plenum are virtually the same as with the 981 Competition Plenum, putting down 17 horsepower and 11 foot pounds of torque at the wheels. The bulk of the power gains from the IPD Plenum begin around 4000 rpm, continues all the way through to redline and become fully realized in the 6000 rpm range. IPD performance gains stay above both factory power curves throughout the entire rev range."
I have been in talks with a major euro tuner and the throttle body is not giving any extra peak BHp
a tune alone gives you 412ps add In the TB and you get 415ps, but adding in the TB makes a big change at the 5k on torque.
this is just the remap only graph, I was told the TB will improve the 5k torque loads.
Seems odd the TB is not giving any peak BHP, but these are the experts.
a tune alone gives you 412ps add In the TB and you get 415ps, but adding in the TB makes a big change at the 5k on torque.
this is just the remap only graph, I was told the TB will improve the 5k torque loads.
Seems odd the TB is not giving any peak BHP, but these are the experts.
Edited by Porsche911R on Friday 17th June 12:09
Porsche911R said:
I have been in talks with a major euro tuner and the throttle body is not giving any extra peak BHp
a tune alone gives you 412ps add In the TB and you get 415ps, but adding in the TB makes a big change at the 5k on torque.
this is just the remap only graph, I was told the TB will improve the 5k torque loads.
Seems odd the TB is not giving any peak BHP, but these are the experts.
Very interesting David, are they saying that a simple remap increases the power significantly? Are they also showing the original figures before the remap as rumours are that the car produces more than 385bhp as standard.a tune alone gives you 412ps add In the TB and you get 415ps, but adding in the TB makes a big change at the 5k on torque.
this is just the remap only graph, I was told the TB will improve the 5k torque loads.
Seems odd the TB is not giving any peak BHP, but these are the experts.
Edited by Porsche911R on Friday 17th June 12:09
Would the throttle body help with improved breathing and the ram air effect at higher revs (stationary rolling roads can't simulate this) and the apparent peak power produced below 6k revs instead of 7k+.
What are your thoughts on the effect on mpg which is dire in standard tune?
I have no idea, as the car def must have some ram effect, that graph in just a map and bmc filter.
so 90% of gains are just from software.
I doubt the cars are >385BHP the 981 SPyder have 10less bhp and as fast in a straight line, talks of 400bhp are bulls
t imo.
My car is feeling better now on 2.5k miles for sure, a map and TB is tempting.
but manifold and IPD pleum seem to offer no extra gains worth talking about, although if you want the best you fit every thing I guess.
did some one just do a surry RR and get 358bhp !
so 90% of gains are just from software.
I doubt the cars are >385BHP the 981 SPyder have 10less bhp and as fast in a straight line, talks of 400bhp are bulls
t imo.My car is feeling better now on 2.5k miles for sure, a map and TB is tempting.
but manifold and IPD pleum seem to offer no extra gains worth talking about, although if you want the best you fit every thing I guess.
did some one just do a surry RR and get 358bhp !
Edited by Porsche911R on Friday 17th June 13:22
Porsche911R said:
nice after that long wait, feel like I have had mine ages now, 9 months in fact !!!
enjoy the car :-)
I know, such a long wait! Funny really, it is the last colour I expected to go for, because the camera always makes it look purple, when it is really very blue. So glad I travelled to see one in this combination first, otherwise I'd have discounted it.enjoy the car :-)
What the hell is the door lock under the handle for when you don't get a physical key!
Edited by mdianuk on Friday 17th June 16:08
mdianuk said:
I know, such a long wait! Funny really, it is the last colour I expected to go for, because the camera always makes it look purple, when it is really very blue. So glad I travelled to see one in this combination first, otherwise I'd have discounted it.
What the hell is the door lock under the handle for when you don't get a physical key!
The key blade is in your remote.What the hell is the door lock under the handle for when you don't get a physical key!
Edited by mdianuk on Friday 17th June 16:08
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