Die katte is uit...vir 'n hele R300 - update on fuel consump

[JamesC]

So, having read up exhaustively (no pun intended) on the cats for a year now, I was plunged into removing them yesterday not by design but by accident.

The one cat was broken and I could clearly hear the crap rolling around inside it.

Stopped at SupaQuick in Potch and gave instructions clearly...cut out the back two and replace with straight pipe, use hammer and some force and break the front two out...two hours and R300 later, the cats are gone. Sensors still in place (I knew this was a 50/50 decision but at R600/dummy sensor was prepared to take it) and "siedaar" all running perfectly with a bit of grunt.

Will monitor the fuel consumption and see if there is a ever so slight improvement. As for power, I think it is a bit in the head, because you hear that V6 grunting so it feels like there is even more power and more responsive to the throttle.

[Huismoeles]

Daai is glad nie n slegte prys nie.
Beste wat ek kon kry was 750 en dis net vir skoon slaan.

[Masekind]

Waar kan ek van daai dummy sensors koop het nie cats ini maar ooki sensors nie

[JamesC]

SupaQuick verkoop die dummy sensors

[Masekind]

Dankie sal gaan kry

[JamesC]

OK, so I can tell you in town I used to get about 6.1-6.3km/L and since the cats are gone, getting 6.9km/L. Will be driving opend road next week to see what happens. At this stage then R300 very well worth spending.

Next thinking of adding a snorkel as that might have another small impact. Which means I will be at a total spend of just over 2K and impacting positively by perhaps 1km/L better on consumption. No, financially speaking, in my mind makes much better sense to spend R2k for a 14% gain in fuel consumption than spending R6k on a chip and then another R6-8k on branches for a 10% increase.

My 2c's

[Kaaskrul]

Snorkel wont give better fuel consumption.

[JamesC]

I thnk I might gain a very slight improvement - biggest reason would be to protect the engine with cleaner air:

From 4x4connection
Q. Will fitting a Safari snorkel effect the fuel consumption?

A. Correct installation of a Safari snorkel will result in unchanged or slightly improved fuel consumption.

from 4x4community

In most cases, however yours specifically, a snorkel will let your engine breath-in a LOT cooler air. This means in effect that your engine will get more air-mass in, a fact your injection will notice hence will supply more fuel. The result is a noticeably higher performance - which, if you do not use all, will translate in a lower consumption. You will definitely notice the better performance, and, once you have this, will probably not notice a lower consumption. The performance-gain not only comes out of the more fuel injected but in part also from a higher (volumetric) efficiency of the engine, your engine works better with cooler air as the effective compression ratio is higher. [Edit: This is exactly the same why turbocharged motors, to gain even better performance, fit Intercoolers.]
Have a look under your bonnet. The airfilter sucks air from under the fender - which is, for all intent & purposes, closed off from the outside.... except that it has openings on the inside. Air on the inside comes through the radiator, therefore has a temperature quite a bit higher than ambient. The snorkel will supply air at ambient, quite a large difference actually.
Also, the intake of a snorkel is mounted high-up, by definition a position where less dust is sucked in. It will still pass through the airfilter though, and keep in mind that no perfect airfilters exists. Conclude with me that less dust will enter an engine if a snorkel is mounted, and this should translate to a longer lifespan. In practical terms though I think you'd be pushed to notice this, however it is true nonetheless.
The Safari snorkel also faces forward hence is claimed to have a Ram-Air (forced induction) effect. It probably has too, if you drive 250Kph, but I'd discard this 'benefit'.

It surprises me that none of the posters seem to know these advantages. Sure it looks great & wading fine etc, but one earns the cost back - paid in performance rather than savings.

From ARB

So what other benefits can a snorkel bring? Better airflow is certainly one. Taking the air intake out from under the inner guard where it’s prone to dust intake, or out from the warm airflow of the under-bonnet can be beneficial to fuel economy and power, but it really is specific to the vehicle model. Reputable manufacturers like Safari spend a lot of time perfecting snorkel designs so that any gains that can be achieved from increased airflow are taken advantage of.
But one of the best things about raising the air intake of your vehicle by fitting a snorkel is that you move the intake further from the inner guard and the dust that is produced by the front wheels. Some snorkels also allow the fitment of Donaldson cyclonic pre-filters. Their clear bowl design lets you see the dust they separate from the airflow and they are easily serviced. The result is cleaner air, less clogging of the filter and ultimately lower servicing costs.

[Mud Dog]

Agree with what is said there. Fit the snorkel! Besides 'looking good' the long term benefits are worth it.

[theos]

Hi James

Ek was ook skepties maar na jou "post" besluit ek toe dit is nou sulke tyd.
Ek was hier in Randburg by SupaQuick. Daar is toe 'n snaar met sulke tattoos op sy kuite wat baie stories het. :alvarin: Maar toe gelukkig is die einaar ook 'n Hilux man. hy het reeds sy katjie uit en hy se hy spaar redelik baie diesel. Hy stel toe voor dat ek 'n vryloop knaldemper in die cat se plek sit. Volgens hom het die lee cat redelik sleg geresoneer en dit was steurend.
Ek volg toe sy raad. Die trok trek nou soos 'n stoomtrein man en hy is net so still soos vantevore. Ek gaan oor twee weke Elisras(deesdae mos Lephalale) toe en sal dan die branstof verbruik toets. Ek het reeds 'n snorkel op en kan jou nou se ek het geen verbetering in diesel verbruik gekry nie. Dit is net goed om te weet dat die trok koel skoon lug kry.
En in elk geval lyk 'n snorkel net reg!!!!
Ek gaan 'n nuwe post laai met die ou kat vir die manne wat sou belang stel om hom skoon te slaan en te laat insit.

[Umpalumpa]

Hy stel toe voor dat ek 'n vryloop knaldemper in die cat se plek sit.

Wat het die hele affere jou toe terug gesit? As ek mag vra.....

[theos]

Dit was R500 bokke.
Maar ek is heel tevrede.

[Black Sam]

JAMES did you go freeflow right through or did you just do the cats
How does he sound now?? I had a complete freeflow on my Hilux and boy did he sound serious
Will this mods work for the Tuna as well and how far can one go?? The Tune is much heavier on fuel as the Lux.

[Umpalumpa]

Dit was R500 bokke.
Maar ek is heel tevrede.

Se vir daai man ek sien hom binne 2 weke se tyd! Dis glad nie n slegte prys nie.
Moet nou net van die boot af kom en dan by hom uitkom.

[Tarquin]

cats are terrible stuff, if they break and block your exhaust and you carry on driving like that you most likely to blow a manifold gasket, they increase consumption and reduce power!
cut the out

[Kaaskrul]

Ek het op my Tuna die Cat uitgesny en net n straight pyp in gesit.
Hy het glad nie harder gedreun nie.

Ek wil nog net so rapsie meer km op my Hilux sit dan gaan ek dieselfde daar ook doen.

[JamesC]

I just took the cats out and even left sensors in place. I did not go for complete freeflow so still have one box right in the back.

Car was always very quiet but now has a grunt to it, especially when you put your foot down. Nothing serious or disturbing and still very gentleman like...but you can now hear it is a V6...

Putting the snorkel on because

a - it looks good
b - it is functional and prolongs/protects engine by allowing cooler/cleaner air
c- if it effects a minute saving I would be happy.

My car has 320 000km on it and I intend putting another 300 000 on.

[JamesC]

1000km later...60% long distance at speeds of 140-160km/h I managed 6.94km/L...not too shabby hey naaig...