Porsche GT4 RS Kicking It’s Bad Habits - Randy Pobst Suggested Mods

[@jackzhang6705]

Amazing editing and thoughtful analysis!! Totally enjoyed watching this one.

[@ItsTrackTime]

Glad you enjoyed it!

[@LemtemPoktui]

I can't help but feel Porsche purposely gimped the 718 GT4 RS so that it wouldn't out perform the 992 GT3.

[@basketball798]

I hate when manufacturers do that! It's so frustrating

[@ItsTrackTime]

I also believe Manthey had to follow orders when creating its 4RS kit.

[@MikeMW87]

@@ItsTrackTime there is a fix made by the company ssc ...and misha that does nurburgring laps says its more stable .

[@alpeena]

Porsche did same w/- 914/6....the 911 chassis has to remain top dog for the company to work

[@flsupraguy]

No "gimping", the 911 is just a faster chassis/platform....

[@TwiceNightly]

Dream is to follow in your footsteps! Terrific video - information was plentiful and well-presented. God-willing, one day (soon), I'll secure my own P-car and see you at the track! Subscribed!

[@ItsTrackTime]

Thank you for the visit and kind words! I'll be waiting for you in the garage!

[@jeffreylang9812]

I love hearing your narration of your data and thought process. I’ve only had my GT4 on track one weekend. Hopefully I can get to a point where I can dedicate more time to driving on track. Thank you for sharing your insights and Randy is awesome.

[@ItsTrackTime]

Thanks for the positive feedback. It's good to hear people find this content useful. Did you enjoy driving your GT4 on track? Usually the first time is both overwhelming and exhilarating at the same time.

[@jeffreylang9812]

Yes my first track weekend was great. I was with the St Louis PCA. They do a great job with the HPDE.

[@betsyperk1227]

This is so interesting, thank you for making this video.

[@ItsTrackTime]

Glad you found it interesting.

[@JetFuelOnly]

Great analysis! Keep having fun!

[@ItsTrackTime]

Thank you! Keep your videos coming as well - Very informative!

[@tgs4400]

Great analysis. I really enjoy your videos. Can’t wait to see the rematch with the new mods.

[@ItsTrackTime]

Thanks! I'm thinking a well driven 992 GT3 RS should be in its sights with these changes.

[@todapwr1]

I really enjoyed this video and hearing Randy feed back. It’s reassuring hearing his feedback on the MCS since I pulled the trigger on a set for my 911s. One reason I went with them is they’re not far from me in Atlanta and having that support close by. Keep up the great videos. 🤙

[@ItsTrackTime]

I've heard great thinks about their support around the southeast. Stories about them rebuilding shocks at the track for customers. I think you made a good call by picking up a set.

[@TRZ0612]

@@ItsTrackTime I have MCS 2-way remotes on my 718 GT4 and needed a rebuild on them because of a shop mishap. They got them done for me in a 10 day turn around and that was during their busy season. They are awesome to work with and very supportive. For this reason alone I would choose them over the Manthey kit if you are in the US

[@ItsTrackTime]

Thanks for the feedback on MCS. Great to hear more positive comments on them.

[@sodazman]

Having driven the GT4 RS and 992 GT3 the biggest difference I've noticed is stability under braking, bumps and cornering. The 992 with its new suspension geometry makes a world of difference on the track.

[@ItsTrackTime]

Yeah the 992 GT3 has a very sweet frontend. I couldn't believe how much mechanical grip it had with just 200 wear tires on it.

[@sodazman]

@@ItsTrackTime It was blown away by it too. It didn't have any of the usual 911 understeer/snap oversteer characteristics at all and just stayed glued the whole time.

[@robbinconner9061]

Yup. 992 (any model) is definitely better over bumps and rumble strips, more stable under braking and noticeably more planted on corner exit.

[@corsacrew3966]

Also 992 has wider tires and wider track that the Cayman ;)

[@chrislamprecht]

Thanks for putting this together, great analysis. Looking forward to the next comparison. I hope to be at Schnellfest in November.

[@ItsTrackTime]

Thanks! That would be a good target. Hope to get out on the track with this stuff in early Oct when the first cold front comes down.

[@robertburris7692]

Great analysis, I think you have it pegged. I raced against Randy in CFR at Sebring and daytona, and he is amazing.

[@ItsTrackTime]

Thanks for the confirmation. We'll see where this next step takes us...

[@grippgoat]

Hearing Randy talk about symptoms of bad shock settings is actually super useful for me. I actually have MCS 2WNR on my BRZ, but have been kinda struggling to dial them in. Hearing him describe some of the behaviors in the same way I've been thinking about them gives me more confidence that I'm going in the right direction.

[@ItsTrackTime]

There should be folks in the field that can help you dial them in. I was lost for a while with a set of KWs and then just started burning track time adjusting one parameter at a time. If the lap time got better I kept moving in that direction until it got worse or I ran out of adjustment.

[@TheAnubite]

love your data oriented approach!

[@ItsTrackTime]

Thanks for the positive feedback!

[@fstlnj29]

Think the drag on the downforce negates some of the hp advantage. My theories on lap time is it all comes from whatever is happening between initial brake application and track out, with a focus on the v min. Working on braking is not sexy simply because to be good at it you have to be comfortable being uncomfortable. So most don't work at it hard enough.If the car is over slowed into the apex you pay an additional penalty all the way to top speed or the next brake zone whichever comes first. I think all the upgrades will help and shock adjustment will allow better braking, cornering, and throttle application. Can't wait to see what the results are. As always, really enjoy the vids, your passion for the sport, and listening to Randy is a bonus. Toe curl!

[@ItsTrackTime]

Thanks for the support! Yes I agree, starting with a momentum car made me really focus on Vmin at each corner. If I got that wrong my right foot couldn't get me out of it.

[@maintenancethrottle]

Absolutely fantastic video and analysis! Really enjoy following your journey to get it dialed in. 👍

[@ItsTrackTime]

Thank you very much for the positive feedback! Good to know others find these videos useful.

[@maintenancethrottle]

@@ItsTrackTime I should have also mentioned I think your content helps anyone that goes to the track, ie don’t have to be a Porsche owner to benefit. 👊

[@mitchlewis535]

Sounds like a good plan. You could just stiffen the front sway bar to tame the rear end, then add the MCS shocks so it’s better over the curbs. (digressive valving) You’re smart to go with the MCS shocks over the KW’s as parts will be easier to obtain and probably cheaper. Penske’s are also a great option.

[@ItsTrackTime]

From the factory the sway bar settings were medium/medium so when the backend started coming out we did just that - moved the front bar to stiff. After driving this setup Randy recommended moving the rear bar to soft. Good to hear you also recommend MCS - Thx.

[@davec3568]

Good vid! I got MCS RR2 coilovers this year for my SS 1LE Camaro, so far I'm really impressed. Figuring out the best place for, and then mounting the remote res's took a while. I thought with much higher spring rates vs oem magride the car might get upset more on curbing, but that's not the case, it's still super stable and doesn't get upset easily. Also, still good to drive on the street, but ymmv on that!

[@ItsTrackTime]

Good to hear!

[@Dom4rs]

Awesome vid. Thanks for sharing!

[@ItsTrackTime]

Thanks, glad you enjoyed it!

[@beninvictoria]

Thank you! Are you going to put the Dundon Kit on the car? So curious to see what happens if you do that - I've got a stock car with exception of camber plates and rear toe links and looking to see what to change next!

[@ItsTrackTime]

Yep the full Dundon kit is inbound! Debating on whether to stage the parts or just point them all on at once. Could do MCS, pull data, Aero, pull data, Header back system, pull data but that would take three track weekends and probably 6 months. I'm a bit impatient so I will probably do it all at once and try to figure out how to drive it.

[@robbinconner9061]

Nice analysis.

[@ItsTrackTime]

Glad you enjoyed it

[@JCK0944]

I already have TPC offset toe links on my 4RS and they help a little with the bump steer, but don't resolve the issue. Before MCS, I am thinking of playing with the DSC sport box to see how far I can get with that. It seems there is a common theme with Porsche having a lack of rebound in more than a few of their cars. Just how the factory wants them to be I would presume. So why not just undo that philosophy and add back some of that lacking rebound. The DSC can control both rebound and compression for slow, medium, and fast shock movements via the ride height sensor. All on the lap top, so easy to make repeated adjustments. So maybe raising the rear a few extra mm for travel, slightly softening the compression, and increasing the rebound could help settle the rear end. You can also program the suspension to dramatically lower the the shock values on only the front inside corner under high loads on the opposite side of the car. This is dynamic depending which way you are turning and makes the inside front of the car float over rumble strips without being upset as much. This allows the front wheels to stay more panted on impact, which keeps the whole car more level. That way the rear of the car does not get unsettled by the front of the car before its wheels even hit the rumble strip.

[@MikeL-mb1ny]

How do you 'play with the DSC sport box' - do you adjust the software / map ?

[@ItsTrackTime]

It would be nice if they allowed us to make these adjustments without having to hack into their system. We get a menu of exactly two settings - not great for track driving. The 992 GT3 RS seems to be the only factory car with a larger amount of adjustment in this area.

[@JCK0944]

@@MikeL-mb1ny Yes the multiple software maps are highly adjustable. Overall shock dampening front and rear, adding more or less under compression and rebound, adding more shock in front under braking to reduce dive. You can also decreasing only the front inside shock setting to say 30-50% transiently when the other side is under heavier G, so that when that wheel hits the rumble it is much more compliant that the other three wheels. The list goes on.

[@JDM_FD]

Quality content 👌

[@ItsTrackTime]

Thank you for the feedback!

[@analogperformance7666]

Have really enjoyed your 4RS videos. I have one and have adapted some of your setup. I wonder did you consider the aero pieces at Alekshop? Looks like GT4 RS Clubsport clones to me so I assume would work quite well but have not anything about it. Would love to know how those Clubsport pieces stack up against the others.

[@ItsTrackTime]

Thanks for the feedback! Good to hear you found the video useful. I believe the parts Alekshop is selling are from a Chinese company that goes by "Silver Rocket" on the web. I don't know how well engineered they are and really don't want to experiment with them until I see someone having success with them on the track.

[@mikaelhelmin2462]

Great video! Will the Added Downforce harm the top speed? If so will increased corner and exiting speed counter and exceed the loss? In the end you probably have a nicer handling car and that alone is a win! 😊

[@ItsTrackTime]

Thank you! This setup is said to be very low drag and we're adding 30hp to the top end so I shouldn't lose any top speed on the straights plus I should be able to brake even later with the added downforce - thereby extending the straights.

[@vantagesc]

The bar chart is mega. I'm not a good enough driver though to keep chasing the lap time game with endless mods. Once the car is dialed in enough to feel good, then I'm done.

[@ItsTrackTime]

Making the mods is half of the fun but as we all know the amateur driver is usually the weak link.

[@MikeL-mb1ny]

Great content Barry, I'm just setting up my 4RS, but not sure I want to go to the cost and extensive mods of Dundon. One guy I met at COTA in a GT4 doing good lap times (2:22s he said) suggested 4RS was overstrung, the spring rates are much higher than the GT4, could one lower rates and help prevent such big bounce back, negating need for more damping? I have MCS on my BMW track cars & they are great but it all gets expensive to chase a few seconds...

[@ItsTrackTime]

The spring rates are higher on the 4RS. The Spyder RS, on the other hand, has softer springs so that might be a place to grab specs and part numbers from. 2:22 is a great time for a GT4.

[@wuaw2011]

A lot more up and down movement on the GT4 in the triple screen comparison. Seems like suspension is working much better on GT3s

[@ItsTrackTime]

I was talking to Felix today and he said he has never upgraded the shock on the GT3s he maintains. Maverick, on the other hand, always upgrades to MCS. But most folks agree the GT3s handle much better than the 4RS straight out of the factory.

[@yuaus]

Great video but aren’t the GT3’s on slicks and you’re on RE71Rs? I would think that would be a huge advantage?

[@ItsTrackTime]

Thanks! GT4 RS - Hoosier R7s GT3 - Hankook Slicks GT3 RS - Hoosier R7s

[@refuztosay9454]

Couple of things - best quote “I have to lift and I don’t want to…” ; question - I’m retired now and keen to do some track work - I used to race moto so the urge is still there but with age comes the cage (cars) - so wondering what’s the annual run rate for expenses or even per session (tires, rebuilds, brake flush/pads, all that stuff) and track fees? Leave the car out of it - I’m thinking 911 s with mods or a 718 trim lower than gt4 rs. I won’t be able to use the speed of a higher end kit for a while if ever so thinking it’d just get me in trouble and most more.

[@ItsTrackTime]

For the 4RS every weekend requires: Track fee $1000 Tires $2100 / 1.5 = $1400 Tire Mounting $250 / 1.5 = $166 Pads $1100 / 2 = $550 Brake bleed $400 Oil change $300 So something like $3800 For my 987.1 race car Track fee $1000 Tires $1600 / 1.5 $1066 Tire Mounting $250 / 1.5 = $166 Pads $1100 / 6 = $183 Brake bleed $400 Oil change $300 So something like $3100

[@KhaledAmr]

nice comparison. have you thought about SSR performance kit? they did some great job on the 4RS upgrade kit. Thanks for the comparison

[@ItsTrackTime]

Thanks, the SSR kit requires you cut into the car to open the air flow for the hood pass through. I was trying to find a kit that didn't require cutting or punching holes into the car. When I first saw the Dundon kit on the web I figured they must have molested the car to get all of those parts onto it. However after seeing John's car and discussing it with him I was pleasantly surprised to find it was completely reversible and didn't require any drilling or cutting.

[@KhaledAmr]

@@ItsTrackTime its true the SSR requires to cut though the frunk however AFAIK its a replaceable part that can be fit back. their Kit has a special suspension and front aero too. i think they all good solutions for the 4RS, its unfortunate how Porsche handicapped the 4RS from its full potential. will be waiting your feedback. enjoy the modding journey, its half the fun.

[@ItsTrackTime]

I was really hot on the Manthey kit but now believe the 4RS kit was handicapped by their 50% Porsche ownership. Porsche won't let them go full out on the downforce given it might infringe on the GT3's lap times. Their new kit for the 3RS looks very crazy because the 3RS has nothing above it in the food chain right now.

[@redpriest26]

Great video. Has anyone tried the DSC Sport controller? They add a little bit of rebound on the rear under braking but I'm curious if the ability to fine tune some of the damper settings that way (without having to go to MCS) would make a difference there. Obviously it's not exactly plug and play to change the corner settings and the interface is a little arcane to work with. It dials out a lot of the 4RS nervousness on the street, but I think the lap times usually end up the same if you just go with stock settings.

[@ItsTrackTime]

Interesting thought...

[@lambrosstamos4494]

Can you mix and match? For example the MCS with the Manthey aero. Either way, I think Randy is having great fun.

[@ItsTrackTime]

The springs, shocks, and aero are all matched so if you mix components it likely won't work optimally or at all. For example the Dundon kit has 2x the downforce of the Manthey kit so the suspension has to be a lot beefier.

[@jefflin1400]

Do GT4s have the same front suspension compartments as GT4 RS? Just got my GT4, would like to have -3.5 camber on the front as well. Was going to purchase camber plate, front tie rod end and some shims to get there. However, in the video you said you achieved 3.6 by only camber plate and shims?? Makes me wonder if I need the tie rod end after all? Would really appreciate if you could confirm this. Thanks

[@ItsTrackTime]

The front suspension of the GT4 RS is a hybrid blend of parts from the front suspension of the 991.2 GT3 and GT3 RS so I can't guarantee that the changes we made to my GT4 RS will be directly applicable to the GT4. However yes we only used front camber plates and shims to achieve -3.5.

[@jefflin1400]

@@ItsTrackTime thanks for the reply, I’ll look into it a bit more. Cheers.

[@AutomaticProductions]

I can hear him say lower the rear!

[@domonokun]

What mods were on the 4rs during randy's lap?

[@ItsTrackTime]

Basically setup changes, tires, pads, and over axle pipes.

[@bearbare2406]

Were there additional laps done by the GT3 and GT3 RS to add to the data?

[@ItsTrackTime]

There were but I don't have them. The two used were saved because they were the best lap times for each car. However I will say Maverick had a much faster lap through Turn 11 in the works when the checker flag was shown so he had to pull the plug. Pulling that partial data would be interesting...

[@mdub048]

Damping.

[@997GT3R]

Manthey Kit works only on Nordschleife. This is all big Marketing. If at all, then the suspension kit is worth it. The big benefit is that your approved remains valid. I would never risk my guarantee on that car!

[@ItsTrackTime]

Correct the Manthey kit is warrantied if installed by a Porsche dealership. However I've found the dealerships don't know anything about track driving or track setups so when you talk to them about this type of equipment they just give you the "deer in the headlights" stare.

[@JCK0944]

@@ItsTrackTime If you go the Manthey route, talk to Felix and have John do the work here in Dallas. He is the best mechanic around and knows everything there is to know about setting up these GT cars

[@ItsTrackTime]

John who? Which company does he work for?

[@thughknower758]

Focus on the suspension first and the car will be faster. Get the car to absorb the imperfections in the road better. It will be easier to drive, be more fun and it will be much faster.

[@ItsTrackTime]

Agreed, I have a 987.1 with JRZ dampeners and it handles much better than the 4RS. I'm hoping MCS will close this gap.

[@thughknower758]

I'm gonna give you a tip. When Randy says he needs more rear shock dampening. He's asking for 3 things. 1 more shock travel. Usually you can only get that by raising the vehicle. People don't like doing that because it's not aesthetically pleasing. I guarantee if you give the vehicle a more usable stroke in the rear Randy will be able to be flat in all the corners he wants. 2 better use of the rebound and 3 the compression stroke. If you optimize the springs usable amount of compression. But once you raise the ride height to where the shock is usable under compression you will find the sweet sauce. And instead of Randy applying the throttle through the corner and the car going into a slide the extra ride height will work the compression stroke properly and the rebound mechanism will maintain traction for the tire and the car will rotate properly through the turn improving your laptime. I've said a lot. I hope this helps.

[@ItsTrackTime]

Randy was very sensitive to rear bump steer. I know many folks control this by reducing the travel of the rear wheels - more travel yields more bump steer - more bump steer yields more toe-out at the top of the stroke. I believe they are controlling this by reducing the stroke using better dampeners. Thoughts?

[@z06van21]

@@ItsTrackTime Unfortunately, that is the biggest disadvantage of having struts in the rear. The amount of toe change thru the suspension range is much larger than a multi-link set-up. On this platform, you fix that by dialing A LOT of toe in on the rear (like 2.3mm to 2.5mm per side) AND limiting suspension travel (which has the undesired effect of limiting traction). MCS (or something similar) helps with the suspension travel as the quality of the internals and superior damping keeps things from getting too harsh when limiting travel. You can only do so much though with a strut rear-end though and it really is embarrassing of Porsche to stick struts on a sports car that costs six figures. Having more suspension travel (like @thughknower758 suggests) only works well if you are working with at least a multi-link or double wishbone. More suspension travel on struts just creates more extreme toe changes.

[@ItsTrackTime]

Do any of the aftermarket "bump steer adjustable" Rear Toe Links work well enough to reduce or completely fix this undesired behavior?

[@DundonMotorsports]

Great analysis Barry! A full Dundon aero/mcs/power 992 GT3 manual went 2:14 in the hands of Cameron Lawrence. You’ll have more power and better gearing in the 4RS. The combo of the 3 aspects for your package. Aero, Suspension, Power will allow Randy to haul ass as he likes to do. When you do this next time with Randy we might see if Ted can come out and lend a hand!

[@ItsTrackTime]

It should be epic and any help Ted could provide would be much appreciated!

[@DougSlmon]

❤😂😢😮😅😊😊😊😊😊😊😊😊😊😊😊 that Randy is a damn good driver. I we need him to drive for Porsche at 24 hour Le Mans he is a damn good driver

[@ItsTrackTime]

I'm sure he would be up for that!

[@DougSlmon]

@@ItsTrackTime and the other races cause I seen him race. He is a very damn good driver and he knows what he’s doing. He also has a Mustang that he drives and races. We need a good driver like that so we start kicking some ass in every race, I’m tired of Corvette andpiece of shit Ferrari

[@JeffMackler]

Its, not it’s.

[@palefaced1]

I've had both and the 911 is the better car.

[@ItsTrackTime]

Common belief among many - I just prefer mid engine balance.

[@jaredbell174]

your not even stopping at same place on track....silly

[@ItsTrackTime]

If it's a turn we do. If it's a Vmax or Vmin we obviously don't