Originally posted by giddyup306:
I just got my built-to-the-hilt 3L hybrid back on the road! I was going to do a true dual exhaust system on it and had planned on using the stock Y. So I cut it apart. I'm taking a new job and moving so I needed it to run. I didn't want to take the chance of it rubbing the ground. Nor did I like the idea of putting the pipes under the tank (which is what I would have done). I was searching some old posts and Demon said that it didn't feel like he gained a lot of power but the transition was smoother. So I guess it wouldn't help much anyways. So I had ordered a MSDS Y from Marty. After getting the headers and now the Y I honestly have to say that they make killer stuff! And that comes from a guy that owns a set of Kooks headers.

Anyways my situation is a bit unique. I honed out the secondaries 2mm (from 34-36). I then backed off the secondary linkage being that the butterflys are slightly oval.

This is where I think I get my driveability problem. I only pull 15.5"hg at idle at 800 RPM. It sometimes has a rolling idle and revvs up to 2K then pulls 20"hg but will go down after a few seconds. It also holds higher RPMs when I go to shift.

I'm confident that I do not have an external vac leak.

I have a CEL and 6 codes (4 hard and 2 pending). All catalyst monitor related so they are negligable.

The only PIDs that were off were my LT fuel trims which were both at 17. Makes sence being that I am using the SVT injectors and it still thinks that it is a 2.5l. The other PID that was off was my BARO. For my altitude, 153-154 is perfect. I am at 162.

I think that this is just the nature of the beast.

So my question is can this problem be tuned out via Excal2 or is this out of it's limits? I tried a few searches but came up with people that had porblems after optimizing TBs.

Also since I got your attention, the 96 block that I used had a much bigger hole for the KS. So big that I the bolt will not go through the KS. Any suggestions? W/o any advance (I have 0* of advance at idle). This thing runs like [censored]! Honestly I think my old 2.5 would take it. Their is much more power to be had.

Here is a list of my mods...

3L Hybrid

-3L valves
-ported heads
-Secondaries honed 2MM
-heads, secondaries, and UIM all port matched on the secondary (primaries left alone)
-MSDS headers and Y
-Unorthadox (I think.. was on the car...) pulley
-Some high flow K&N FIPK (one again on the car...)
-CR 11.25:1
-65MM TB
-Magnaflow Mufflers
-FRPP wires

THANKS!!



I need different information.
I thought you had an SVT? If so, then you would not have an issue running svt injectors, so I'm gonna guess that you have an SE. Going on the assumption that you are using an SE pcm with SVT injectors.
So first can you confirm what car and pcm, maf, intake style, and any other non-stock parts you are using?

Okay, here are some ideas:
You can't trust the vacuum reading if your idle air control valve is opening and closing as in a rolling idle.
You may or may not have a vacuum leak.
You have hard codes but need to tell us what they are.
Baro reading probably isn't a big deal right now.

Lets go with the fact that the SE PCM is expecting 17# injectors and its own MAF. Are you useing the stock MAF right now? You should be at least for now.

Given that you are running SVT injectors = 19# on a car expecting 17#, that means you should be running rich. The long term fuel trims would be in the negative each by some amount, nothing that the pcm couldn't compensate for normally. On the other hand the engine is bigger and it will have to increase the fuel delivery and may have to trim positively for that. But on that note, the injector settings in the code are not listed by size. They are listed by about four or five numerical scalars, such as injector slopes and such. Since it takes four or five numbers to describe the injector to the pcm then it stands to reason that the pcm just doesn't know how to fire the injector and who knows what the hell it is doing.
We will need other information first on this.

For the time being put the stock injectors back in, put the stock maf on if it is not already on. Check for vacuum leaks, check for egr leaks.
Look at the IAC valve as a source for problems. Then drive it around without getting on it too much. Clear all the codes and pcm memory when you do. Then do some datalogging of long term fuel trims, injector pulsewidth/duty cycle, and look at the O2 sensors to see how they are cycling at idle and cruise.
Report back a qualitative opinion on the O2 sensors, idle quality and cruise when you do this as well as any numerical information you can give us.
Don't forget to check fuel pressure at idle, and snap the throttle to see if it jumps up when the vacuum leaves the FPR, or pull the FPR vacuum and see.
Also, do you have vacuum secondaries? If so they may not be closing at idle if you have a vacuum source problem. This would cause all kinds of headaches./

I don't think you should be getting any driveability issues form the widened secondaries as many people used to crack them anyway and I ran the same setup and never had a problem from it. The problem is most likely the engine being bigger, the injectors, airflow and fuel delivery are further off.
People with SVTs using stock SVT hardware can easily support a 3L change without a single tuning mod. With an SE its a different ballgame.


Former owner of '99 CSVT - Silver #222/2760 356/334 wHP/TQ at 10psi on pump gas! See My Mods '05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red '06 Mazda5 Touring, 5spd,MTX, Black