What adjustments after Walbro on a CTSC?

Arshad

Arshad

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I just got a Walbro 255 installed to replace the OEM pump on a low-boost CTSC setup. The dyno testing I had conducted earlier seemed to indicate that I was running on the lean side, and I was also concerned with overdriving the 14 year old OEM pump so I decided to go the walbro route.

However, after installation, I feel like the car has a bit less power now (which I suppose could happen if it's running rich?). The mechanic who installed it said he would adjust the FPR so that it matched comptech's spec, but that it might still be a good idea to tune it on a dyno.

So my question is, what is there to tune? My understanding is:

1) Adjust the base setting with the FPR, which will then affect how much fuel is ultimately delivered when in open loop mode?

2) I had the ESM voltage set to 2.92 ... does this need to be adjusted at all with the new fuel pump in place, or should I leave that alone?

Others who've installed a walbro on a similar setup: Did you have to adjust anything after installation?

Thanks!
 
I've also known people to damage their engines using an Apexi or other O2 or MAP signal modifier on a CTSC.
Run the car on the dyno with a GOOD wide band installed and check your new a/f #'s AFTER the cats. Only FP is adjustable, as far as tuning go. Use FP to achieve AFR. Its easy.

MB
 
Thanks for the advice Mark. But why do you suggest after the cats, as opposed to before the cats? I thought that the best place to put the wideband was pre-cat?
 
Arshad said:
Thanks for the advice Mark. But why do you suggest after the cats, as opposed to before the cats? I thought that the best place to put the wideband was pre-cat?
Click to expand...


Because I had not had enough coffee yet. AND I'm dyslexic :eek: Good lookin out, and thanx for the correction. I'd hate for anyone to take my original comment UNcorrected.

MB
 
Same issues...replaced my pump, but not sure what I should do next?
 
Onsoku: You were hitting 347RWHP prior to the fuel pump upgrade on a 3.0 engine? I'm assuming you're running the 9lb pulley. Can you give details on what other specific mods you have, ie which exhaust, headers, etc?

Unfortunately I still haven't had a chance to put the car on a dyno yet. I know I'm running rich (loss in power, smell, blackened bumper), but I figure if it's running rich, then it's also running safe -- so no big rush. I hope to get it done soon though before I have to put the car away for the winter.

Any recommendations for a good shop in the Toronto area? Hey Mike, when is Autowave opening up a Toronto location? :D
 
After looking at what the AEM did for the CTSC, I think you should pick one up. I think you would be very happy and I am sure there are plenty of people in Toronto that can tune one.
 
Yeah but I'm not sure if I would trust anyone here in the Toronto area. I know there are competent AEM tuners, but it would take forever to start from scratch and I'd rather pay to fly up someone with a good base map and NSX experience than take my chances with a local. Devin out in Michigan used to be a good option, but now that he's left, I'm not sure where the closest competent guys are. I'd love to go the AEM route next summer -- I need more power!!! :D
 
Arshad said:
Onsoku: You were hitting 347RWHP prior to the fuel pump upgrade on a 3.0 engine? I'm assuming you're running the 9lb pulley. Can you give details on what other specific mods you have, ie which exhaust, headers, etc?

Unfortunately I still haven't had a chance to put the car on a dyno yet. I know I'm running rich (loss in power, smell, blackened bumper), but I figure if it's running rich, then it's also running safe -- so no big rush. I hope to get it done soon though before I have to put the car away for the winter.

Any recommendations for a good shop in the Toronto area? Hey Mike, when is Autowave opening up a Toronto location? :D
Click to expand...

No, the dyno run was after the fuel pump install. Prior to the install, I made 320 something WITHOUT THE HEADERS.
I currently have the CTSC standard option, Cantrell CAI w/UNI, DC Sports Headers & Exhaust. My dyno sheets are in the trunk at GreenLight.
 
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WHAT?! :eek:

Both are corrected numbers? You made 20+ rwhp from JUST swapping in the Walbro? That doesn't sound right, especially since you were already making good power for a 3.0 w/ 6lb CTSC -- so it's not like you had a fuel delivery issue before.
 
I was searching through earlier threads on Walbro installs and it seems that a lot of people have replaced the comptech RRFPR with the AEM FPR after going the Walbro route. Is it pretty much a certainty that the return on the RRFPR isn't sufficient for the additional flow from the Walbro? ie even after adjusting the RRFPR on a dyno will I still be running rich?
 
a walbro will overwhelm the stock return and result in pressures of >75 at idle (my experience) the aem FPR is a perfect solution
 
Arshad - if youre looking for a tuner, lets see what we can do come spring time. Im almost certainly going SC and if I do that, Im getting SOS' AEM EMS also.

We can split the costs of bringing someone up. Lets get Johnny to go high boost for his CTSC- which will force him to get an EMS also.

Its gonna be a looooonnnnngggggggg winter.
 
Johnny is already high-boost... but I don't think he's too happy with the current tune. If the three of us (four if we can convince stu!) go AEM then it might be economical to fly someone down -- or at least find a local shop to give us a good deal on the parts and tuning.


a walbro will overwhelm the stock return and result in pressures of >75 at idle (my experience) the aem FPR is a perfect solution


Thanks! Maybe I should get this part installed before I go ahead and book some dyno time.
 
WOODY said:
a walbro will overwhelm the stock return and result in pressures of >75 at idle (my experience) the aem FPR is a perfect solution
Click to expand...
The Aem fpr is not the solution, this is a wrong statement. you would only go with the Aem FPR if going with a stand-alone engine management system. Keep with the Comptec regulator. This regulator is what you call a rising rate regulator. Where as the AEM FPR is a 1:1 ratio regulator" meaning that for every pound of boost, there will be one pound of fuel pressure added". The comptec works in the same method but, they are 12:1 ratio regulator "for every pound of boost there will be twelve pounds of fuel pressure 6psi of boost=72psi fuel pressure.
If the Comptec regulator was taken off there would be no fuel system for the CTSC system resulting in a very lean engine possible KAboom.

Just my two cents
Sorry woody had to correct your statement.
 
dynomike said:
The Aem fpr is not the solution, this is a wrong statement. you would only go with the Aem FPR if going with a stand-alone engine management system. Keep with the Comptec regulator. This regulator is what you call a rising rate regulator. Where as the AEM FPR is a 1:1 ratio regulator" meaning that for every pound of boost, there will be one pound of fuel pressure added". The comptec works in the same method but, they are 12:1 ratio regulator "for every pound of boost there will be twelve pounds of fuel pressure 6psi of boost=72psi fuel pressure.
If the Comptec regulator was taken off there would be no fuel system for the CTSC system resulting in a very lean engine possible KAboom.

Just my two cents
Sorry woody had to correct your statement.
Click to expand...

I concur with Mike...GreenLight told me the same thing when I wanted to upgrade my FPR. If I recall, my a/f was at about 12.5 @ 2750rpm, with a dip to 11.4 at VTEC engagement, then a constant rise back to 12.3 to redline.
 
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The Aem fpr is not the solution, this is a wrong statement. you would only go with the Aem FPR if going with a stand-alone engine management system

sorry if I was unclear, the walbro will overwhelm a stock regulator and return and result in the higher pressures. Providing for the additional fuel needs during boost is not the function of the aem fpr, it is simply a means of modulating the increase flows of the walbro. you are correct, one cannot replace the other without a means to increase pulse width on the injectors
 
Onsoku said:
I concur with Mike...GreenLight told me the same thing when I wanted to upgrade my FPR. If I recall, my a/f was at about 12.9, with a dip to 11.8 at VTEC engagement, then a constant rise back to 12.9 to redline.
Click to expand...
If you are running a 12.9 afr under full boost I would be a little concerned about the engine. At that airfuel it is unsafe to run a boosted car. I would try to richen the car up before it costs you a lot more $.
 
Quote:
<TABLE cellSpacing=0 cellPadding=6 width="100%" border=0><TBODY><TR><TD class=alt2 style="BORDER-RIGHT: 1px inset; BORDER-TOP: 1px inset; BORDER-LEFT: 1px inset; BORDER-BOTTOM: 1px inset">Originally Posted by Onsoku
I concur with Mike...GreenLight told me the same thing when I wanted to upgrade my FPR. If I recall, my a/f was at about 12.9, with a dip to 11.8 at VTEC engagement, then a constant rise back to 12.9 to redline.
</TD></TR></TBODY></TABLE>
dynomike said:
If you are running a 12.9 afr under full boost I would be a little concerned about the engine. At that airfuel it is unsafe to run a boosted car. I would try to richen the car up before it costs you a lot more $.
Click to expand...

Good idea. Now the 12.9 A/F was at the tailpipe, which was why we thought I'd be safe. But, I did detect a ping when I did a 3rd gear pull. So I sent it back to GreenLight with the hope that maybe I'd only need to run cooler plugs instead of fattening up the A/F?
 
Nope you still need to richen the A/F ratio up. The tailpipe sniffer will be accurate(Wideband in a bung is best.. but..), but may be a little off as far as rpm on the dyno chart. You add that A/F ratio with the high intake air temps with the Comptech, and I'm not sure how more have not blown up to be honest.
 
Elite said:
You add that A/F ratio with the high intake air temps with the Comptech, and I'm not sure how more have not blown up to be honest.
Click to expand...

Knock, Knock.
 

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