GRX mods

[Peter Vee]

My patrol is now officially 3yrs old and out of warranty (still only has 29000km on the clock) and I am now set to add a free flow exhaust.... which would have had an impact on warranty.

I can recall swapping notes with Tinus about the "zorst" he had added by Noise Boys in Centurion... any pointers as to who to consider for the work in Joburg / Pretoria area will be appreciated.

Also, by recall, it seems to be a case of changing the back half of exhuast as opposed to messing with manifolds?

Cheers,

Pete

[DawidT]

Hi Pete,

Same scenario as you, mine out of warranty with only 31 000km on clock. Did my complete exhaust and manifold last week and in today for dyno. Unfortunately I did not do a dyno before the changes and hence will not be able to compare the before and after results. The Patrol however do feel more responsive, but it is easy to confuse the lekker sound from the exhaust with better performance.... I put on a TNT system - 63mm pipe with branches. Speak to Tinus, a lot of things to consider that I did not think of. I kept my old spares just in case the system is a disaster and I need to change back.

[johanp]

Van der Linde Developments in Kya Sand put a 63mm stainless steel freeflow on my 4.5 and it worked and sounded good.

Cheetah Exhausts in Rosslyn put a 76mm mild steel freeflow on my 4.8 but it was too noisy for my liking. I took it back and they replaced the rear silencer with a quieter one without hesitation. Their service was very good. They built the freeflow from where the pipes join the manifolds. There are sensors in the 4.8 manifolds and that is one of the reasons why they don't replace them.
The airflow through the manifolds is good enough and branches will not make a noticable difference in power or fuel consumption.
After driving around for a few weeks I decided the 76mm was still too noisy for me. I didn't take it back to Cheetah but replaced the 2 silencers with 63mm freeflow silencers at another place to get the noise levels down.

When the time comes to replace the mild steel exhaust, I will take it to Van der Linde for a stainless steel system.

[Chris Skinner]

Hi Peter - I am interested in the outcome of this discussion as could consider doing same on mine. Are you going to do a dyno before and after?

[David]

According to Powerflow all boxes except for the big 'suitcase' are already freeflow. If your Patrol is equiped with catalitic converters it might be worthwhile removing them but watch out for error codes. Mine didn't have any.
I just replaced the suitcase with a freeflow and there was no noticeble improvement in consumption - only more noise.

[Schalk]

you can go to exuast man in honeydew for some good prices. they do bosal exaust's

[Tinus lotz]

Peter
Daar is geen verskil op die dino met of sonder branch nie die standaard manifold is klaar n branch .die onder bonnet temps gaan baie op as jy manifold afhaal veral as jy stadig in die veld ry dan skakel airccon af en hitte lees verkeerd
Muas en vanderlinde beveel dit nie aan nie hulle se ook geen verskil met of sonder nie
Verder is daar te veel beweeging op die engine kyk maar na die shocks op die engine moutings n brancch maak te solied en dan breek of die branch of die studs in die head trek uit . Daar is ook 2 vacuum pype wat oor die exthoust kruis een vir diff en een vir tank breather hulle brand ook maklik af as eerste stuk pyp na manifold sonder heat shields is .
Ek stel voor vervang die stelsel na die pype tot agter of haal net die cat uit en die coffin box dit sal werk

[Tinus lotz]

Askies ek was nie in kantoor nie en die letters is klein op my foon dan skryf ek soos n graad een
Verder as jy met Jacobez praat en met graham cumming hulle het baie probeer maar as jou manifold nie stukkend is nie los hom daar is n klomp komplikasies wat met n branch kom sonder om iets te wen jy kry wel beter om aggterste box te vervang en cat uit te haal as jy een het nie tonne beter nie maar wel n beter throttle response bo 3000 rpm .ek dink die snorkel en beter uitlaat sonder box en cat maak n verskil

[Peter Vee]

Thanks for all the tips thus far - much appreciated!

Tinus - ek nie van plan om die branches te verander - plan is om net die agterse gedeelte te vervang - sal later kontak maak rondom detail tips.

Groetnis,

Pete

[AndriesS]

Ek vind dat daar baie uitlaatgas in dei kajuit kom as dei agter deur oop is, ek het gesien party buig die exhaust dat hy nader aand agterwiel uitkom, werk dit beter? kom daar nie gas in as die linker agte deur oop is nie