I need more fuel!

[Ricco_04]

Hi all,

After a good trip on the rollers, I need a bit more fuel before fine tuning.  I currently have full de-cat (scilenced center section) Apexi twin filters and a crummy back box.  With this im hitting 85% at 0.8bar (stock pressure?)

I have an Apexi GT on the way (still :Snoring  ) and am thinking of having a bigger SMIC, like the Greddy.

Question is, what or where shall I put the injectors - which is best.
Plenum
Elbow
Uprated Primarys

any other options?

Cheers, Ricco.

[iaint]

Hi all,

After a good trip on the rollers, I need a bit more fuel before fine tuning.  I currently have full de-cat (scilenced center section) Apexi twin filters and a crummy back box.  With this im hitting 85% at 0.8bar (stock pressure?)

I have an Apexi GT on the way (still :Snoring  ) and am thinking of having a bigger SMIC, like the Greddy.

Question is, what or where shall I put the injectors - which is best.
Plenum
Elbow
Uprated Primarys

any other options?

Cheers, Ricco.

Uprated secondaries every time.  Ideally 1650\'s.  Full replacement rail is relatively cheap and more reliable than replacing the 850\'s with the 1300\'s (bored out 850s!).

Keeping the stock primaries will still give decent response and performance at lower rpm where bigger injectors will not be too happy.

[Ed_RX7]

on the button....when you getting your t70 iain?....two t70\'s in london......now thats special:evillaugh

[Ricco_04]

Uprated secondaries every time.  Ideally 1650\'s.  Full replacement rail is relatively cheap and more reliable than replacing the 850\'s with the 1300\'s (bored out 850s!).

Keeping the stock primaries will still give decent response and performance at lower rpm where bigger injectors will not be too happy.

Cool, cheers for that :Thumbs-up

So the best way is to uprate the secondary\'s to 1650\'s.  This will keep a good idle and have loads of spare capasity. Are there any issues at al with using secondary\'s 2x the size of standard or is it all stuff that can be mapped out?

Just to clarify, is this better than having stock injectors and adding say 2 more 550\'s?

[rmagictastic]

you need not go to all the expense of a full huge secondary rail, just get a bosch put in your tank and some 850cc inj in your primary rail.

unless your planning on making huge power, i personally wouldnt bother with massive fuelling, you will never use it.

my 2p

Rmaj

[iaint]

on the button....when you getting your t70 iain?....two t70\'s in london......now thats special:evillaugh

Just waiting on the manifold so should be a couple of weeks.    What a/r are you running (i\'m going with 1.15).

Cool, cheers for that :Thumbs-up

So the best way is to uprate the secondary\'s to 1650\'s.  This will keep a good idle and have loads of spare capasity. Are there any issues at al with using secondary\'s 2x the size of standard or is it all stuff that can be mapped out?

Just to clarify, is this better than having stock injectors and adding say 2 more 550\'s?

I\'m hitting early 70\'s on injector duty so a becent amount of headroom for the next set of tuning.  Currently running 323/387 rwhp/fwhp on the twins at 1.1 bar to give you an idea.

you need not go to all the expense of a full huge secondary rail, just get a bosch put in your tank and some 850cc inj in your primary rail.

unless your planning on making huge power, i personally wouldnt bother with massive fuelling, you will never use it.

Agree that you\'ll need more than just bigger injectors.  the stock fuel pump is pretty weeny.  I\'m running a BNR33 pump but the bosh 044 is another popular choice (although with some in tank starvation issues on low fuel).  A pressure regulator is also a damn good idea once upping the pump.

My view is it\'s better to overspec and never run out of headroom than underspec and run close to max all the time.  Tune in summer running 85% duty and you\'ll run out on a freezing winters day.

Running 850s all round is only a very small increase over the stock setup but should be good enougn for 290-300 rwhp safely.

[rmagictastic]

Running 850s all round is only a very small increase over the stock setup but should be good enougn for 290-300 rwhp safely.

just a point in case, im currently running 280rwhp and never go above 70% duty with 850cc all round,

Rmaj

[Ricco_04]

Ok then.  Tring to work out the best option.

I want to uprate SMIC Intercooler, cat back & was thinking of getting the I was thinking of adding hardpipes to the equation too (after seeing how much they move on the rollers! )

There is a fella on here selling the greddy elbow with 2 injector spaces
http://www.mazdarotaryclub.com/forums/showthread.php?t=28042

Is this a good mod, better or worse than uprating standard injectors? Pros & cons etc.

[rmagictastic]

ok,

this is my point of view.. if you are going to stay on twin tubs for the forseable future, then your going to make what... 330 RWhp max??

and if you want to make that you will need a front mount IC anyhow.

first thing to do is make a realistic goal for yourself, lets just say 290 - 300 hp
ok? 300hp is enough for anyone and it is very very fast!!

you can make 290 easily enough with a bit of work...

Filters, downpipe, cat out and back box ..problem is you start running out of standard injector power at this point, you will make around 270-280 and the stock injectors will be running at 95-100% (which is bad.)

Now depending on your end power goal, you can modify your fuelling, if you want a 400hp car go and but a secondary fuel rail with fpr and 1600cc injectors (although your twin turbos will start to let you down at about 340hp)

if you want to get your 300 hp, then you dont need to go so over the top, its fairly cheap and cheerfull (i rekon about 500 all in) should get you 850cc primaries in a rail and a bosch fuel pump instaled.

Turning in to a bit of a rant this sorry...

Basically the more air and the colder the air you can shove in to and spit out of you engine the more fuel you can pump in, therefore the more power you get.

To summerise.

1. your turbos WILL be the restricting factor on the air front, they will only let you make about 330-340 bhp (without destroying themselves)
2. my suggestion is to put fuelling in which can cope with 330-340hp, no need to go any further.

Rant over

Love and hugs

Rmaj

[iaint]

Rant over

Love and hugs

Rmaj

Can\'t understanding why you\'re ranting matey - there are plenty of ways to skin a cat and much of it\'s opinion and a trade off between short and long term cost.

I\'m in the \'twins pushed close to max\' category - 323rwhp at just over 1 bar.  Medium-large single on order, aiming for 400rwhp (give or take).

My current stage of tune is a steppign stone to that. If I\'d gone for the minimum fuelling upgrades to support my current power level I\'d have to re do it when going single.  I had planned on keeping the twins the rest of the year but plans change.

If you\'re sure you never want to go further than running 280-300rwhp then sure, go for the cheaper and smaller option.  If you think you might get used to the power and want more later on save money in the long run by doing a proper job now.

Different courses for different end games!  I was where Ricco is a few years ago and could\'ve saved myself £s if I\'d known then where I\'d want the car to go now...

Your post\'s absolutely spot on though regarding the mods for power levels.  I can\'t see anywhere in his posts where Ricco says he doesn\'t want more than 330rwhp though.  I suspect he\'s on the same route as many of us - slowly getting more serious power levels!

*snogs*

[rmagictastic]

sorry bout rant dont really know where that came from... must be the heat.

no aimed at anyone.

Maybe its my time of the month

rmaj

[iaint]

sorry bout rant dont really know where that came from... must be the heat.

no aimed at anyone.

Maybe its my time of the month

rmaj

:rollin

deffo the heat - far to hot in our office today.  Roll on home time.

[Ed_RX7]

Just waiting on the manifold so should be a couple of weeks. What a/r are you running (i\'m going with 1.15).
 
 
Ive got a 1.0 divided...probably wouldn\'t go any higher than your 1.15 though....would be far too laggy....i had a .84 on it and it spooled up lovely....i\'ve found the 1.0 to be a very good comprimise for spool and power....but thats my opinion....whats up with your manifold? and what make t70 you getting?...but i tell you what, the t70 loves 14psi!!!!!!!!!!!!pulls like hell and when you hit 19psi....forget it!!!!!!!!!!!....seriously its ridiculous....and ive driven some of the best supercars out there...:evillaugh

[RobbieRX-7]

Ive read somewhere that a mk4 supra fuel pump will fit and do the job easily..anybody else heard this?

[iaint]

Ive got a 1.0 divided...probably wouldn\'t go any higher than your 1.15 though....would be far too laggy....i had a .84 on it and it spooled up lovely....i\'ve found the 1.0 to be a very good comprimise for spool and power....but thats my opinion....whats up with your manifold? and what make t70 you getting?...but i tell you what, the t70 loves 14psi!!!!!!!!!!!!pulls like hell and when you hit 19psi....forget it!!!!!!!!!!!....seriously its ridiculous....and ive driven some of the best supercars out there...:evillaugh

It\'s a Turbonetics jobbie (sourced through re:worx).

Interesting that you ditched the .84 housing and possibly a good job too.  Was talking to Clive a few weeks ago about housings and he was adamant that using less than 1.0 can lead to premature engine death.  Something to do with not flowing enough to get all teh hot exhaust gasses out of the housings so the tips over heat, expand and bam, dead engine!

the great thing aboutthe T70 is, as it\'s not a prices tubby I can play with different housings without breaking the bank (in theory) to get exactly the characteristics/compromise I\'m after.  That\'s teh plan at least!