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**DONOTDELETE**
11-30-2000, 03:18 PM
With a stage one turbo on the ka24de (370cc injectors, stock internals, stock mafs, JWT ecu), what is the safe upper limit of boost pressure I can run?

I called JWT and Ben told me "370cc injectors and stock mafs will top out around 260hp to the flywheel." He also says that stock internals will be ok around that level of hp so long as there's no detonation. Hmm, if I remember correctly, that Nsport kit at 7psi was 240hp or so to the wheels, so isn't that way over 260hp at the flywheel (like 290-300 or so)? Or does the Nsport kit use stage II stuff like 550cc injectors and Cobra mafs?

I read about people running the stage II kit around 11 psi safely, but what about stage I?

11-30-2000, 07:16 PM
The Nsport kit uses a rising rate fuel pressure regulator (AKA Fuel Management Unit or FMU), IIRC. Supposedly that dyno run was done at 7 psi. Do you have an A/F gauge? Just keep turning up the boost in little increments, and don't let the A/F get too lean (in fact, it shouldn't even get to stoichiometric, it should run on the rich side at all times under boost.

FWIW...I've heard that SR20DET's can run about 1 bar (15 psi) on stock injectors, which works out to somewhere around 300 CFM of air. Assuming similar volumetric efficiency for a KA, 300 CFM works out to about 8 psi on a KA.

If you want to get a little more out of your 370cc injectors, you can add an FMU to increase fuel pressure at high boost. There are adjustable regulators out there that allow you to set not only the ratio of fuel pressure increase, but also the pressure at which the FMU starts working (so instead of raising fuel pressure when boost gets to 1 psi, it can start raising the pressure at, say, 6 psi).

I think Ben is right that the stock internals are ok as long as there is no detonation. However...once it happens, I wouldn't expect your pistons to last long. So be careful! http://www.freshalloy.com/

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by Tim:
With a stage one turbo on the ka24de (370cc injectors, stock internals, stock mafs, JWT ecu), what is the safe upper limit of boost pressure I can run?

I called JWT and Ben told me "370cc injectors and stock mafs will top out around 260hp to the flywheel." He also says that stock internals will be ok around that level of hp so long as there's no detonation. Hmm, if I remember correctly, that Nsport kit at 7psi was 240hp or so to the wheels, so isn't that way over 260hp at the flywheel (like 290-300 or so)? Or does the Nsport kit use stage II stuff like 550cc injectors and Cobra mafs?

I read about people running the stage II kit around 11 psi safely, but what about stage I?<HR></BLOCKQUOTE>

**DONOTDELETE**
11-30-2000, 09:59 PM
I am running 16PSI boost on my CA18DET safely, but I had to get a FSE fuel pressure regulator, because at full boost at high revs, the CO level sould be for most turbo cars about 6%( my car had 3%). After a session on a rollong road I adjusted the fuel pressure to 3.4 Bar from 2.8 Bar (now I won't melt a piston!).

You also could go for a fifth injector setup but this is costly

[This message has been edited by paulo (edited 11-30-2000).]

12-01-2000, 10:39 AM
what size injectors does the CA18DET have?

Asad

**DONOTDELETE**
12-01-2000, 02:32 PM
I am not too sure, but apparently the stock fuel system is good for about 310 bhp

12-01-2000, 02:54 PM
Wow...that means it has bigger injectors than an SR20DET (370cc/min). Interesting.

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by paulo:
I am not too sure, but apparently the stock fuel system is good for about 310 bhp<HR></BLOCKQUOTE>

**DONOTDELETE**
12-02-2000, 09:14 AM
The company that I use prepare CA18DET's to any spec, and soon will be selling a 350bhp kit for the S13!
www.norrisdesigns.com (http://www.norrisdesigns.com)

**DONOTDELETE**
10-30-2001, 04:02 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by asad137:
Wow...that means it has bigger injectors than an SR20DET (370cc/min). Interesting.

Asad



<HR></BLOCKQUOTE>

No they are smaller.

I can run 17psi on my CA18DET if I retard timing a little.

Currently runnin 14psi, ive remapped the EPROM to allow more fuel uptop. and my car pushes 232bhp.

Stock AFM and Injectors are at 90% duty aroun 290hp. So watch out paolo m8. Drop in GTiR injetors which are 444cc. And either remap EPROM , go get a UniChip or make to with an APEX S-AFC to fine tune.

Also 300zx maf give crap low speed drivability. The Japs use em cos they dont care about drivability, just pure power. but a an everyday car (which most are, especially in busy London) I'd say go for a 50mm Maf which shouldnt disturb the ECU signals too much