63mm versus 75mm Freeflow

[Andre D]

Hi Guys

I would like to know the difference between the 63 & 75mm free-flow exhaust on a 2012 3.0 D4d.
I am not installing a chip as yet but would like to gain some better fuel economy.

I would appreciate your comments.

[Thunder02]

Welcome Andre,
Sure you'll have an answer soon.

[Donkey]

I'm no fundi, much as you need the engine to breath better, i.e. by fitting a free flow, but going too big might also compromise you on the back pressure.

[Thabogrobler]

No need for back pressure on a turbo diesel - you want to get rid of the hot air asap, BUT the bigger diameter the slower the flow will be.

My very uneducated guess would say 63 is sufficient, but what the heck, go for the 76!

[Moonunit]

Anyone know the size of the exhaust outlet on the turbo? Would say go with that or slightly bigger and possibly have a new flange made to accommodate the bigger pipe. Agreed with Thabo no back pressure required from the exhaust, so size not too critical, back pressure built by the turbo itself.


Sent from my iPhone using Tapatalk

[janvg]

Anyone know the size of the exhaust outlet on the turbo? Would say go with that or slightly bigger and possibly have a new flange made to accommodate the bigger pipe. Agreed with Thabo no back pressure required from the exhaust, so size not too critical, back pressure built by the turbo itself.


Sent from my iPhone using Tapatalk

63mm. See atrached. Thats how the 76mm system looks. Its a bit thinner where it bolts on at the turbo then goes bigger again.

[janvg]

See the top pipe. Left hand side is bolting to the turbo.

[Haboob]

Andre, I had a free flow exhaused fitted by Dwayne in Pretoria.
I did not have a chip fitted so he fitted the smaller pipe. He recommends the bigger pipe with a chip.
I had a 10 Kw improvement on the wheels on a diagnostic test conducted which improved consumption by nearly 1 km/l
I have a fitted camper which now gets an average of about 9.5km/l.
Hope this helps...

[Reinart21]

Ok, so for the real question. Prices anyone? In the area around gauteng, east rand, mphumalanga. Is there anyone you guys would recommend, or can I do this at my local exhaust shop no hassles? Considering quality and workmanship, does anyone know of special requirements for these exhaust systems, I'm really clueless when it comes to these things.

One thing I know, my Hilux has a dastek unichip, egt is bound to be a lot higher than stock hilux because I still have the stock exhaust system.

[Reinart21]

Also, do we know what is the operating/safety limit on the Hilux's EGT? (Exhaust Gas Temperature)

[Obelix and Dogmatix]

go to dastek for the exhaust as well (Steve's auto Clinic) and they will be able to re-dyno at the same time.

another is viper exhaust on the east rand they apparently also do the black magic of exhaust mods.

Do not just go to your exhaust shop as they generally are replacement specialist of exhausts and not exhaust designers.

JUST DO YOUR RESEARCH PROPERLY!!

[Andre D]

Thanks for all the info on this topic.
It seems there are few guys with the same idea.

[Andre D]

Have had a qoute at Powerflow in North Coast road Dbn for 75mm for about R4500.

[antlo69]

Also try Cheetah in Rosslyn. Masters on freeflows

[DerikB]

Ok, so for the real question. Prices anyone? In the area around gauteng, east rand, mphumalanga. Is there anyone you guys would recommend, or can I do this at my local exhaust shop no hassles? Considering quality and workmanship, does anyone know of special requirements for these exhaust systems, I'm really clueless when it comes to these things.

One thing I know, my Hilux has a dastek unichip, egt is bound to be a lot higher than stock hilux because I still have the stock exhaust system.

Rainart you can try TNT Performance Exhaust Systems in Middelburg. Have seen their work before and it looks good. As soon as finances allow my Hilux will also be heading there!

0132824313

[andrevt]

i have a 76 from the front to the back fitted by SAC Vanderbijlpark sounds different aswell

[Reinart21]

i have a 76 from the front to the back fitted by SAC Vanderbijlpark sounds different aswell

Andre,

Do you have some more information?
Do you also have a chip in the hilux?
Dino? Extra Kw and Nm?
EGT readings?

There are always some variables before and after fitting these type of MODS, and as always very interested parties who would much appreciate some elaboration on them...

[janvg]

I have also a 76mm pipe on my fortuner. It sounds also good.

Sent from my GT-I9300 using Tapatalk

[Reinart21]

I have fitted the 76 mm stainless free flow from SAC,
unfortunately I can't say what the EGT reading is with the OEM pipe, but I can say the standard toyota map with a 76 mm downpipe, doesn't matter how hard you drive it, the temp never goes over 600 C. So Id say it does help the engine/turbo with keeping the temps down.

Is there any indication that the larger free flow pipe will retard spooling of the turbo? Takes longer to get to full boost?

[antlo69]

Not on a diesel turbo motor.

[janvg]

Reinardt wat het jy toe betaal en watse krag kry jy?

Sent from my GT-I9300 using Tapatalk

[Reinart21]

Jan, die 76mm free flow, is stainless, en hy loop van die turbo tot heel agter met een silencer/free flow boks. Om in te sit met arbeit was R6500.00.

Hy begin teen n grootte van 63mm om rede die flange op jou turbo 63mm is, direk daarna vergroot hy na 76mm reg deur to agter.

Ongelukkig kan ek jou nie sê watse krag ek kry nie, om rede ek is nie so seker oor die geloofwaardigheid van die dyno uitslae wat hulle gee nie. Persoonlike redes. Alhoewel ek hom na n ander dyno toe gaan neem wat ek gehoor het wat goeie reputasie het vir akkurate resultate.

Maar tog na die pyp opgesit is het hulle hom "gedyno" en die chip oor "gemap".

Kw was so 143
Nm was so 463 gewees. As ek reg kan onthou, die uistlae lê by die huis

As jy wil sal ek dit inscan en saam sit?

[janvg]

En voel jy darem die verskil.? Trek hy beter? Ek het ook so sisteem op my fortuner en ek is baie baie gelukkig. Die klank is ook mooi. Glad nie te hard nie. Ek het die dieseltorque chip met n pedalbox in en ek smile net al die pad.

Sent from my GT-I9300 using Tapatalk

[Reinart21]

Jong, met die standaard toyota map sonder "added chip features" sou ek sê ja verseker, kan die verskil verseker voel, trek beter, klink ook baie mooi en ook nie te hard nie, waneer jy op spoed is pla hy glad nie.

Ek het n dastek unichip "q" series, so ek sal nie kan sê hoe hy vergelyk nie.

Maar ek sukkel so bietjie om hom uitgesorteer te kry, volgens my moet hy bietjie beter wees met die free flow en chip, voor die free flow het hy ook sterk getrek, so ek vermoet dit is net die "mapping" wat uitgesorteer moet word.

Ek sou graag wou weet hoe vergelyk die 63mm teen die 76mm pyp.

Een teorie is gaan groot, hoe groter hoe beter, en die rede hoekom ek hom laat insit het was om die EGT laer te kry, met die chip kan hy bietjie hoog raak.

Toe hoor ek iemand sê maar gebruik eder die 63mm voor die 76mm, want as jy die grootter een gebruik, gaan die lug stadiger vloei en dan gaan die hitte langer vat om uit te kom? Waar die kleiner een gaan die lug vinniger uitstoot en bob's your uncle.