Reply to thread

See what others are reading now! Try Forums > Current Activity

Message: <blockquote data-quote="renxun" data-source="post: 2426697" data-attributes="member: 33177">just to clear some of the mis understanding of the function of FPR in tuning.Actually after market FPR is only needed when big modification is involved...On our mostly common street car modification there is no need for an aftermarket fpr...why do i say so?upgraded fuel pump must change FPR- NO , because the stock FPR will maintain your stock fuel pressure in your car which are already optimized for your injector to inject fuel to your engine... even with a SARD FPR , with the uprated fuel pump wouldnt change the pressure.. because what changed after your upgrade your fuel pump is your flow, not d pressure.. pressure is maintained..most pl use adjustable FPR to push their injectors to work more... in fact when your injector duty cycle hit 100% and your fuel pressure was increased you will only be able to push slightly more... and your are mostly on the danger side as d optimum injector duty cycle % shouldnt go more than 80%.. it is to give your engine some tolerence just in case if there is any spike happening when you boost.raising your fuel pressure will definitely hurt your low range rpm fuel economy while not giving any xtra gain... turbo engines usually starves fuel at high rpm. by increasing the pressure your low rpm fuel economy gone in the drain.normal aftermarket fpr are 1:1 meaning to say 1psi of boost increase in your manifold will equivalent to 1psi increase in your fuel pressure... so for normal turbo car will be around 43-45 on idle and imagine if your are doing 20psi of boost your fuel pressure will be around 65... for big boost kaki some will even go up to 25psi of boost... and dont forget.... bosch external fuel pump user (which is very common) beware, as bosch fuel pump lost efficiency when fuel pressure is above 70psi.flow will go down... when during idle and boosting up the flow will increase according to your fuel pressure.. however d flow start to drop when its over 70psi..so imagine if your FPR was tuned around 5psi xtra from stock... you will max out your fuel pump 5 psi earlier.... and when flow drop, just imagine your pressure build up with less flow on fuel rail, the moment your injector open and spray fuel, cavitation occur in split sec as your flow drop, half a sec of fuel starvation and your engine gone....rising rate we seldom see in the market but the concept of it is 1:1.5meaning to say .. 1psi of boost, your fuel pressure raise 1.5, another 1psi increase your fuel pressure go up 3psi. its works like geometrical progression. seldom use this.. but there are pl who use them for b.o.t on their NA car with very little boost around 5psi without adding any fuel enhancing device.when to use adjustable FPR...? when your modification had gone big.... your fuel rail changed, you using super big fuel pumps... might be a twin bosch 044, those 450lph fuel pump or any other big pumps available in the market, real large injectors where flow is what they need..... the stock FPR passage cannot accomodate such fuel flow as you can see the hole is dammly small...so when they change to larger capasity fuel rail this is where the aftermarket FPR comes in..... it had better flow and the pressure are normally set back to somewhere around stock 3bar or +-45psi...so there is no nid for any after market FPR unless for the bling bling factor on our street car.... however having a fuel pressure gauge is good to monitor your fuel pressure to observe your fuel pump's health</blockquote>

Verification

The Marketplace Latest

original rare Yokohama ADVAN Racing RG2 17x8.5jj...
- Started by david tao
- Chassis and Wheels
original rare WedsSport TC005 17x7jj offset +40 5H...
- Started by david tao
- Chassis and Wheels
Vifa Speakers Audison Amp
- Started by samuel118
- ICE -In Car Entertainment
original rare Yokohama ADVAN Racing RG3 18x8.5...
- Started by david tao
- Chassis and Wheels
Carbing R35 GTR GTR35 Brake Master Cylinder Stopper
- Started by aycy
- Engine and Performance
GR Corolla Hypertune Bolt On Intercooler
- Started by aycy
- Engine and Performance
Carbing Radiator Reservoir Tank Honda Civic Type R FL5
- Started by aycy
- Engine and Performance
R35 GTR GTR35 Rim Wheel TE37 Track Edition
- Started by aycy
- Chassis and Wheels
Endless Racing Mono6 + Racing Mono4 R35 GTR GTR35...
- Started by aycy
- Engine and Performance
WOT Dual Oil Cooler Kit Civic Type R FL5
- Started by aycy
- Engine and Performance

Posts refresh every 5 minutes

British classic cars go mad in the Ilkley Jubilee Rally 2011

https://www.zerotohundred.com/wp-content/uploads/2011/04/Iikley.jpg

Owner's of classic cars are usually the crowd that takes good care of their cars and hardly go for any extreme motorsports. However, these guys are...

brembo evo 4,5,6,7,8,9 on lancer GT

hi,
anyone here done this mods? i think need to modify the bracket, the std braking system are very2 poor la...so small, i guess gen2 disc much bigger.
can someone help me on this?

got my E8 ... hehe..

harlo, all sifu taikor, i just got my E8, some pics to share ... :) enjoy!
yes, all emblems are customised, original too expensive..