When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
2016 Cayman GT4 - Stage II Upgrade - X51/GTS Power Kit Install
During the summer this car came down to receive our Stage I GT4 upgrade package that consisted of:
- BMC Air FIlters
- IPD Competition Plenum with larger 82mm Throttle Body
- Cargraphic Stainless Steel Racing Manifolds
- Cobb Accessport with BGB Pro Tune
Now she's back for Stage II:
- 991 GTS / X51 Power Kit (Incl. intake cams, intake manifold and factory ported cylinder heads)
- Guard Transmission Limited Slip Differential
- Lightweight Clutch Kit
- Stage II BGB Pro Tune for X51/GTS Retrofit
This car will essentially be the baby brother to the GT4 we recently sold. Stay tuned for the before and after!
John...I think it's easier to bring you down here with all the parts than shipping my car to you!
If PAG mess up the next GT4 in the engine department you know what I will do.....
John...I think it's easier to bring you down here with all the parts than shipping my car to you!
If PAG mess up the next GT4 in the engine department you know what I will do.....
Thanks Cosimo! Only if i can then visit Italy to inspect it all!
Originally Posted by user1029
Stage 3 = all that + 4.0L conversion
The most recent 4.0L builds have all been X51 4.0L builds and the top end power is unbelievable on the race track. We had to put a roll cage in Colonel Mustard because he was exceeding 175mph at Daytona. Sorry for the poor sound quality.
John...I think it's easier to bring you down here with all the parts than shipping my car to you!
If PAG mess up the next GT4 in the engine department you know what I will do.....
We are ready when you are Jose. I think that you would like the additional top end power!
Originally Posted by NelsonF
,
+1, wish you guys had a location in SoCal.
We have built several west coast cars and i have customers up and down the left coast. With the more expensive labor rates and taxes out there i bet we could undercut anyone and even still have room for cross country shipment!
Originally Posted by chillindrdude
What are the predicted dyno numbers?
The Power Kit is advertised as an additional 30 mechanical horsepower and while we have dyno proven that repeadtedly, I think the gains in the top of the rev range are where it's extremely noticeable because the better breathing X51 parts create a near perfect power and torque curve. The X51 Power kit bits really create horsepower and not much additional torque if any; it's advertised with 30 additional and not 1 single lb/ft and i have seen it myself on the dyno. The gains are noticeable above 5K RPM - my project GT4 that was built with all of the same bits as this car produced nearly an additional 80 rwhp over a bone stock GT4 at 6700 RPM where the stock GT4 runs out of air. I had my cylinder heads ported additionally so i think this car will be within 10 hp of my car's making 407 - 415 depending on fuel types and weather conditions.
I have attached the baseline dyno run below that produced about 360rwhp and for comparison purposes, below is a graph of a stock GT4 relative to the dyno analysis from yesterday.
Stock GT4 Dyno Comparison vs. BGB Stage I with Cobb Pro Tune, BMC Filters, IPD Plenum, 82mm Throttle Body & Cargraphic Stainless Steel Race manifolds.
Tempting!!!!
If we have all parts line up and ready, how long do you think it would take to drop engine/transmission, build the stock engine and put back together?
Assuming no problems arise.
FWIW I have almost 5k miles now on my 4l X51 (built by Deman but similar to the BGB builds) and it's been running great. Huge difference over 5k rpm (really 6k-8k), less oil usage than when it was a 3.8, and runs smooth as stock. Some "tuner" engine builds can be a little unrefined at part throttle normal driving or cammed to make great peak numbers while sacrificing low/mid range torque but the 4L X51 has none of those issues because much of it is existing Porsche engineered upgrades. Porsche engineers did a lot of work to make sure the X51 kit added top end without sacrificing low/mid range torque (intake plenum has both a central flapper and flappers on each cylinder runner!) and the 4l bore/stroke/compression 9A1 is already a Porsche option. Anyone on the fence should feel good that this is a solid, reliable, and well engineered upgrade.
I failed calculus in high school but even I can tell the increase in the area underneath the curve is tremendous
Lol..wait til you see the comparison with the X51 bits. We should have the motor back in the car tomorrow and hopefully on the ground Monday.
Originally Posted by jmartpr
Tempting!!!!
If we have all parts line up and ready, how long do you think it would take to drop engine/transmission, build the stock engine and put back together?
Assuming no problems arise.
It's a 3 day process to drop the motor, swap to the X51 bits and then go back into the car. I actually sold this conversion to a customer in Bahrain as a kit and walked him through it but he had a shop. He did say after it was all said and done that he didn't think he would ever do that again. The tools to be able to work on these motors are NOT cheap.
Originally Posted by ajw45
FWIW I have almost 5k miles now on my 4l X51 (built by Deman but similar to the BGB builds) and it's been running great. Huge difference over 5k rpm (really 6k-8k), less oil usage than when it was a 3.8, and runs smooth as stock. Some "tuner" engine builds can be a little unrefined at part throttle normal driving or cammed to make great peak numbers while sacrificing low/mid range torque but the 4L X51 has none of those issues because much of it is existing Porsche engineered upgrades. Porsche engineers did a lot of work to make sure the X51 kit added top end without sacrificing low/mid range torque (intake plenum has both a central flapper and flappers on each cylinder runner!) and the 4l bore/stroke/compression 9A1 is already a Porsche option. Anyone on the fence should feel good that this is a solid, reliable, and well engineered upgrade.
I love hearing this sort of feedback. I spent hundreds of hours making the file for this conversion be smooth as possible and Rick tells me that you love the way your car drives. It's great to hear this sort of feedback and cool when shops can share IP.
FWIW I have almost 5k miles now on my 4l X51 (built by Deman but similar to the BGB builds) and it's been running great. Huge difference over 5k rpm (really 6k-8k), less oil usage than when it was a 3.8, and runs smooth as stock. Some "tuner" engine builds can be a little unrefined at part throttle normal driving or cammed to make great peak numbers while sacrificing low/mid range torque but the 4L X51 has none of those issues because much of it is existing Porsche engineered upgrades. Porsche engineers did a lot of work to make sure the X51 kit added top end without sacrificing low/mid range torque (intake plenum has both a central flapper and flappers on each cylinder runner!) and the 4l bore/stroke/compression 9A1 is already a Porsche option. Anyone on the fence should feel good that this is a solid, reliable, and well engineered upgrade.
Thanks for your input. Did you see a noticeable torque increase as well?
FWIW I have almost 5k miles now on my 4l X51 (built by Deman but similar to the BGB builds) and it's been running great. Huge difference over 5k rpm (really 6k-8k), less oil usage than when it was a 3.8, and runs smooth as stock. Some "tuner" engine builds can be a little unrefined at part throttle normal driving or cammed to make great peak numbers while sacrificing low/mid range torque but the 4L X51 has none of those issues because much of it is existing Porsche engineered upgrades. Porsche engineers did a lot of work to make sure the X51 kit added top end without sacrificing low/mid range torque (intake plenum has both a central flapper and flappers on each cylinder runner!) and the 4l bore/stroke/compression 9A1 is already a Porsche option. Anyone on the fence should feel good that this is a solid, reliable, and well engineered upgrade.
Whats the ball park price here? Asking for a friend that already has a Cobb, IPD plenum/gt3tb, Dundon header.
02-13-2018, 10:53 AM
2016 Cayman GT4 - Stage II Upgrade - X51/GTS Power Kit Install
