got moving after engine rebuild...

took 2 years, of which one was lost after engine meltdown on dyno and ensuing legal issues- to make a long story short, I had to pay for all damage and decided to rebuild with jun internals.Obviously ,I turned to other people for my actual setup.

Now I am driving with breaking-in mapping ( rpm cutoff at 6200,timing retarded)

555 cc nismo injectors(already installed before fatal dyno), rps flywheel, rps street max clutch.

further pentroof manifolds, td05-16g,twin intake without maf sensors(converting temp and pressure to voltage data),eprom swap on main ecu + unichip piggyback.

figures look promising with 480 flywheel hp and 599 Nm at 6000 rpm ,with power still climbing in perfectly straight line at 6000, so extrapolating at 7200 would give 500+hp...

at 0.85 bar!

 

But I have a drivability issue :

 

I must rev to 2000 rpm before rolling and adjust throttle to keep rpm at that

rpm or else the engine will stall

so smooth city driving is out for the moment as I must make the impression

of a motorbike racer on cocaine,revving like a maniac at each stoplight.

 

My new tuner says he would have favored standard 370cc injectors supplemented with 2 injectors ,one before each throttle body to avoid this problem.

(I know the mixture is still a bit too rich at low rpm but I doubt everything is attributable to this factor)

 

Is this typical for a light flywheel and/or big injector setup or am I just clumsy?

 

greetz

rik

got moving after engine rebuild...

took 2 years, of which one was lost after engine meltdown on dyno and ensuing legal issues- to make a long story short, I had to pay for all damage and decided to rebuild with jun internals.Obviously ,I turned to other people for my actual setup.

Now I am driving with breaking-in mapping ( rpm cutoff at 6200,timing retarded)

555 cc nismo injectors(already installed before fatal dyno), rps flywheel, rps street max clutch.

further pentroof manifolds, td05-16g,twin intake without maf sensors(converting temp and pressure to voltage data),eprom swap on main ecu + unichip piggyback.

figures look promising with 480 flywheel hp and 599 Nm at 6000 rpm ,with power still climbing in perfectly straight line at 6000, so extrapolating at 7200 would give 500+hp...

at 0.85 bar!

 

But I have a drivability issue :

 

I must rev to 2000 rpm before rolling and adjust throttle to keep rpm at that

rpm or else the engine will stall

so smooth city driving is out for the moment as I must make the impression

of a motorbike racer on cocaine,revving like a maniac at each stoplight.

 

My new tuner says he would have favored standard 370cc injectors supplemented with 2 injectors ,one before each throttle body to avoid this problem.

(I know the mixture is still a bit too rich at low rpm but I doubt everything is attributable to this factor)

 

Is this typical for a light flywheel and/or big injector setup or am I just clumsy?

 

greetz

rik

 

Hi Henry,

 

I wouldn't consider the injectors to be a problem. I, like many others, are running with Nismo 555's and have no problem at all. Is the chip you're running, got retarded timing for low revs too? - that would definitely have an adverse effect.

I'll send you my .bin file if it helps....?

 

Cheers

Simon.

>> twin intake without maf sensors(converting temp and pressure to voltage data),eprom swap on main ecu + unichip piggyback.

 

Are you using a HKS VPC ?

If so, has the VPC been programmed for 550CC injectors ?

 

>> My new tuner says he would have favored standard 370cc injectors supplemented with 2 injectors ,one before each throttle body to avoid this problem.

 

VERY bad idea

when using systems like this the 2 cylinders on the back of the engine (5+6) are running extremely lean and you'll most likely have another meltdown.

 

-Eric

air filter or mapping, had to rev mine more with a lightned fly, but not much more

to Simon: yes, thanks, please send your file for comparison.

 

Indeed the timing is retarded also in low revs!

I'll mention your suggestion to my tuner right away.

 

My e-mail is :

fa493705@skynet.be

 

Thanks for everyone's input so far...

 

greetz

rik

Hi Henry,

 

I had strictly no problems with 555cc and JWT ECU. Now, with the Doolz, I have had this problem, caused by turbulences (but I have the Strosek fascia). I have put the Doolz and the 2 filters highest that I could, and now the problem is solved. That seemed so crazy that I tried one more time to lower the Doolz : the problem reappeared !!!!

 

Happy to see your car running. I have also made a dyno yesterday with the same tuner than you and we compare both dynos : congrats !

My dyno was not good : 455 rwhp at 1.2 bar. Olivier says that the problem comes from my restricted exhausts. But maybe also from my boost controller E01 : start boost and gain where at the minimum.

455rwhp is a lot of power imo, I make that 546 at fly! What is you spec?

As Henri F., I have TD05-16G, 555cc, Doolz, ...

We made the dyno at the same place : we have almost the same curve, but at 0.8 bar for Henri and 1.2 bar for me :headvswal

 

Remark : Henri has more power than he says (our dyno gives a low 'flywheel' extrapolation). I have seen his dyno in rwhp : he has at least 10 more rwhp than me on all the rpm range.

With the 'classical' conversion, he has 465 rwhp/0.83 ~ 560 flywheel hp with 0.8 bar !!!