Chris651

I know there are a few threads of installing GT4 front bumpers on the 981 Cayman S and a few companies who sell GT4 body kits. I’ve read good feedback from guys installing the NR Auto poly one. I seen another company Bayson R Motorsports selling a Polypropylene one as well. They sell lots of body kits for all makes and models but I can’t find any reviews from this company for the GT4 bumper. I did find reviews of 996 guys using their front lip and were quite happy with fitment. If anyone who has experience with purchasing from these guys and if yes were they satisfied with install, fitment or customer service. I would love to here from members before I commit to one or the other. Thanks

Jacob Sami

The bumper is made out of Polypropylene, which is what OE bumpers are made out of, Many are also made out of polyurethane but non the less, both are better than Fiber Glass material. one of the main reasons why i have not did the GT4 swap is because i did not want Fiber glass! not only painting it is hard and can leave waves and cracking problems, just not worth it, since this kit is made out of Polypropylene i will defiantly get one and report back.


*** Ordered it already lol**

SoCal-NSX

For the price of the NR auto gt4 front end you could get the OEM GTS front and rear sport design kit from most Porsche dealerships.

although I like the GT4 front end a bit more, Unless I was going to do the whole GT4 conversion (front, back, side and wing)

I think I would go with the GTS kit....OEM will have much better fit and finish

https://www.delawareporscheparts.com...CABEgKBc_D_BwE

Jacob Sami

I personally already have the GTS kit on my s lol, This way i can swap whenever. as for the rear i will keep the GTS Valance on the car since i have backup sensors. the only way around that is to get Aftermarket CF rear that does have Holes for the Rear sensors. but thanks for the info. Plus the NR Auto it is overpriced for fiber glass IMO.

9Gyarah

Just finished installing the ECS one and the fitment was 99%. Only trouble I had was on the undertray. I did a lot of research before deciding which one to go with. I did get the GT4 ducktail from Bayson R and fitment was 100%. I am almost 100% sure that ECS and Bayson R use the same vendor out of Taiwan so what you are getting is the same. What I did like about the one from ECS is that it inclued the GT4 diffuser so that's a $400 to $500 saving.

Before you decide to take this on, I have to warn you that it was a lot of work primarily because no instructions are included and I had to figure out a lot of stuff on my own by trial and error. If I was to do it again it would be straightforward.

9Gyarah

NR now carries Polyproplene but yes they are overpriced by around $500.

9Gyarah

I respectfully disagree. I have a GTS and went with the GT4 bumper. Difference is night and day.

Jacob Sami

Well mines is in route, I also ordered the OEM GT4 bumper Absorber, i recall when i did my GTS i had to get that as well or my bumper sagged a bit. to stay safe i ordered the GT4 Absorber . i have seen the ECS one and i agree they do seem to be exactly/similar from the same vendor and this one does seem to have the front lip as well.
can you help out on what exactly too look out for regarding the installation, did you order any other OE parts? Also i want to find a rear GT4 Valance with sensors to accommodate, i know they have CF rear aftermarket ones have sensor holes but the factory does not, so i am guessing either try to find a plain black one ( prefer ) aftermarket with sensors or go CF rear with holes for sensors and later upgrade the front lip to CF to match ( keep the GTS one for now )

any help is appreciated boss.

9Gyarah

So I went without the absorber primarily because no one confirmed the GT4 absorber would fit the CS or CGTS Impact bar. I am not sure why yours got a Sag as the absorber never really makes any direct contact with the bumper. it is not designed to support the bumper. If your bumper was installed right there should be no way it should sag as its supported by 3 screws and 2 clips up top and then 2 screws on the sides and multiple at the bottom where it meets the undertray. It would have to weigh a ton to get past all that and sag. Can you elaborate?

For installation, if you got the NR auto one it already comes pre-assembled so you should be fine there as the biggest challenge was assembling it.

For OEM parts I did not get any as most of the stuff in the kit fit except the holes don't quite lineup for where the under-tray meets the wheels well trim. Ideally you want to get the GT4 ones but they are $205 a piece so I decided to make this one work by drilling new holes in the tray and attaching it. I can help you more once you get our kit and have questions.

The GT4 diffuser does not have any room for sensors. I decided to do a sensor delete as I really don't care for them.

Jacob Sami

Part of the sagging was because those clips were worn out as well and had to get new ones, the other reason was the prior owner who had the GTS bumper already installed had some of the hoses for the headlight washers were not OE, as if he used some regular autozone hoses to extend it to some parts in the area, and i did not bother to order the original smaller lighter hoses , perhaps this time i will do that. that added weight to the bumper and it was noticeable. the car also did not have any abosrber prior, either the old owner threw it away when he swapped for the gts bumper , so the body shop told me to get it anyways, ( $55 ) , The new clips helped IMO but no telling how accurate, for this GT4 one, ill make sure to get the proper hoses for the washer so we wont have a weight problem.

SoCal-NSX

did you do the full conversion or just the front?

pics???

9Gyarah

I still don't see how a bumper can sag without the foam. Point I am making is that the foam does not support the bumper as it's not the intended purpose for it so adding or not adding it will not help with sag.

As far as the hoses, etc go I just trasnferred over everything from the GTS bumper. Can you confirm the GT4 bumper foam piece fits the CS/GTS Impact bar? The part numbers for the impact bar are different so want to confirm it fits before I decide to get it.

981-505-121-80 for GT4

981-505-121-02 for CS/GTS

There is also a $200 difference between the two impact bars.

Thanks.

Jacob Sami

Bumper absorber might not be the reason it is sagging, it could be just the worn out loose clips i had and i had an issue with the passenger fender i ended up replacing and now i don't have that issue, non the less, i figured getting the GT4 absorber might be needed and i can be wrong, $55 for me won't hurt. i also just placed an order for some hoses 000-043-204-79, all three long ones are the same part number. so i would finally replace whatever fabrication hoses the old owner had. impact bars do seem different which implies the absorber might not be needed or won't just hang in there, i would like to still have it even if i had to run some masking tape around my absorber that i have to hold it in. ( as man other car makes have as well ) , I will be the guinea pig and report back if it helped or not or was it needed or not. as for the bottom trey part thanks for that. i will take that into consideration. to really have a fully functional GT4 kit it is a good idea to get all parts, like impact bar, absorber, intake ducts etc. since it is aftermarket i will settle for the least but closest i can get to OE.

Here is the absorber ordered by the way : 981-505-777-80

9Gyarah

Thanks a lot. Look forward to your reply. I secretly hope it doesn't fir because I don't want to open the bumper again. lol! That said i noticed the port numbers are different mainly because the when you look at the impact bar, the part numbers include the foam pieces so they obviously can's be the same even if the impact bars are the same. However I donot understand the $200 difference unless that's GT car tax.

After going through the kit install I think for perfect fitment the must have OEM parts are the:

OEM GT4 front ducts:OEM Part Numbers:

• 981575321801E0
• 981575322801E0

OEM GT4 brake ducting. OEM Part Numbers:

• 98150450182
• 98150450181

Personally I would skip the brake ducting as that's $410 and you cna just drill a new hole in the undertray to bolt to that. Not worth so much money. The front side ducts however make sense since they are only $50 each. I didn't get those because the ECS tuning one was flush.

SoCal-NSX

Nice!

So this is the kit you got? https://www.ecstuning.com/b-ecs-part.../0ecs981gt4ft/

shows it comes with DRL's and what looks like the rear defuses and pretty much everything you needed including the ducts too?!!

Not bad for $1850

please post pics asap