I have been reading some good threads about intake preasure and velocity, bigger throttle bodies, balance tubes etc. My intrest is in the EVEN delivery of air and fuel to all cylinders, short of taping 6 wide bands into the exhaust manifolds (some one was selling one recently) how do insure that an even combustion is arrived at ? They are actually 6 x EGT http://www.aus300zx.com/forum/showthread.php?t=276403 If you had "balance" information from each cylinders "burn" could you do a programmed off set in the factory ECU for each cylinder so slightly increased or decreased ammounts of fuel were injected so even power was arrived at based on air delivery differnce from bank to bank and intake runner to intake runner ? I have heard of rear pistons running hotter due to less water cooling, and possibly running leaner due to air flow differnces, the balance tube seems to be an answer to this, size increase help ? additional as across the front intake hard pipes, although I think that it would be more bank to bank from uneven boost/waste gates etc. Hopefully I'm not dribbleing shit but O2's/wideband can only deal with bank to bank, what if one cylinder is running lean due to air flow issues from the plenum. I was even considering getting my new 555's flow tested for piece of mind again if they measure close can you adjust them or offset in the ECU preasure differnces in the rail could effect evenness ? I believe by "balancing" the production of power it will contribute to stronger running more reliable engine . Is this what engine dyno's and after market computers are for ? Even on an engine dyno you would still need 6x taps into the manifold. Novice opinons as well as expert welcome
Not possible with Nissan ECU..... To have individual injector control you would need an aftermarket engine management system. The best you can do with the oem ecu is to use a WB on each bank to determine the leanest and base your tune on that. Having your injectors flow tested to check uniformity is always a good start. I'd hate to be trying to put 6 WB sensors into TT manifolds
A lot of the top drag teams have a WBO2 in each runner. Most of the mid to high end ECU's have indicidual injector trim. Microtech don't, but the Emanage Ultimate does I believe that the Hatech E11 does as well. I think that the EGT in each runner is a great compromise between ignoring the problem and trying to put 6 WB's in. You'll be able to get enough data to know what's going on.
My opinion....... All water cooled engines have a "hot spot", its just more noticable in some engines than others. Generaly its a result of poor casting or a water jacket design that's too small for the actual water to move through at a dependable rate in that area. Vee configeration engines have differant issues over an inline engine but the resulting hot spot will still exist...... Basically its all relevant to the waterpump being at one end of the donk ! think yourself lucky...... ZX's have 2... most only have one ! I think for a 'stockish street car' this would be way over the top........ the differances between each injector would be minimal to a point that most tuning aids would be unable to pick the differance. Perhaps if you had access to a F1 garage and tuner you'd be on the money as for the perfect tune "on the day"...... the level of balanceing and blueprinting is proportional to the available equipment Your quite right in beliving in a balanced power production will produce more power..... if all the cylinders are producing the exact same HP then performance will be higher due to the other cylinders not having to carry a weaker one. Unfortunately in the world of mass production the variations in parts can be extream when micrometers are applied, thankfully the engine builders know this and adjust their tollerances to suit. Back in my "racing days" I've seen new conrods vary in length by almost a millimeter ! ..... we actually spent a day going through hundreds of conrods to find 8 that were identicle in length ..... Pistons measure up with wild variations that at times seem unbelevible yet for 'normal use' they opperate quite well. Balancing an engine is a good first step in obtaining the hidden horses that lie within, its also an affordable excersize...... Blueprinting....... thats a whole new level of wallet thickness ! :bash:
What the hell are WB's ? sorry its early wide band Can injectors be "adjusted" if they flow test differnt ? If you tune to the leanest bank then obviously there has to be a leanest cylinder in that bank so assuming that they are running even would be a mistake, so you need to creep back 5% to ensure that the leanest cylinder is not being neglected ? I assume this would be the job of a good tuner.
The cheapest and easiest way to adjust the airflow into the back two cylinders. Would be to machine an opening in the plenum just before the back runners and have an adjustable sliding door so the amount of air can be tweaked up. Fixing the one sided feed on the fuel rail would also help poor cylinder 6. You could keep the factory ECU then.
HAHAHAH are you serious ! Would a big bore ballance tube help or even multiple balance tubes ? Id probably go with 6 x hoses as close to the lower plenum back into the intake with adjustable valves to adjust the flow and rob the cylinder ummmmm jokes. Yes will be looking to dual feed the fuel rail. Straight up am keeping stock ECU probably with a NISTUNE setup.
Thats incredible I thought when I bought foged rods and pistons that they would be indentical, what are you sposed to do turn the pistons ? How much differnce would a mm make to compression or clipping a valve
What your saying is that WBO2 is better then EGT for determining and balancing power in each cylinder. What if some bright spark developed sparkplugs with thermocouples in the electrodes that could be used as a tuning aid only to "balance" and adjust trim in after market ECU, would combustion chamber temperatures give you info to work with ?
Unlikely as the response time for a thermocouple is too slow to cope. Its a matter of actually presenting the sensor end to the temp source. It has to be carried, and protected by something metal (usually) and that something adds a considerable damping factor to the sensors response time. However the theory is sound enough. Tuning by EGT works well...AFTER you determine what the best temp is for maximum power and minimum damage factor for that engine setup via EGO's!!! WB's are a much faster responding sensor better able to deal with varying gas readings. L8tr E
After market management system with individual cylinder trim, crank as much advance as u can into your cool cylinders at the front
Wow check this out read page 150 onwards on this link. http://books.google.com.au/books?id...X&oi=book_result&resnum=5&ct=result#PPA151,M1 Then relating to the last few lines of page 150, this link. http://www.optrand.com/products.htm I wonder how much they are
And thats the issue really ! Manafacturers make millions of conrods....... just think how many 350chev rods are out there right now Not forgetting all the other makes & makers aswell Obviously they dont all fall from the same cast / mill / lathe etc... so there WILL be variations however small. Multiply that by machine 'A' that has new cutters against machine 'B' thats getting a new cutter tommorow.... & you have even more variation ! The designers of engines realise this and allow for the variations accordingly, which is why you'll often see a measurement with a plus or minus value..... we even see that in many electrial components, the TPS on a zx for example. NB: The largest "allowance" I've ever seen was the inner rear wheel tub on the XB falcon coupe ...... it had a +/- value of 9" ( this was done so they could fit bigger tyres under the cars for the bathurst series back in the early 80's ) Buying forged rods and pistons is a step in the right direction for closer tollerances, but there will still be minor differances however small..... it may be the hole centres, overall length, weight, even the angle the boring has been done may vary ever so slightly, but the tollerances will be far better than a set of "off the shelf" rods & pistons. Just think of the guy that actually made the forged rods..... lets say he made a batch on Friday when he was dreaming of the wild w/end of sex he was about to have with his stunning G/f........ & he does another batch on the Monday after he's discovered vids on the net of his G/f and their 60yearold neighbor banging away in the back seat of his restored 57chevy ! :bash: All one can do is hope like hell when they grabed your rods that they all came from the same palletbin :bow2: Your Injecter flow testing suffers from much the same issues...... What do you do if one is down in comparision to the others ? buy a new one to fix the solution, so now you have 5 'old' injectors & one new one...... or do you buy 6 new injectors and hope they are all within tollerance???? What if one of the new ones is flowing a much higher flow ? Does one buy another single injector or a whole new set and try for 6 that flow similar ????? and then the guy that made your rods got the sack on Monday and started his new job on tuesday....... flow testing your injectors Like I said..... Balancing an engine is a good first step in obtaining the hidden horses that lie within, its also an affordable excersize...... Blueprinting....... thats a whole new level of wallet thickness ! & then some :zlove: Kingy
