Sprintex Supercharger & Gibson Header Install

[merdock69]

Well, I spent yesterday installing my Sprintex supercharger and new gibson header. So far so good; no CEL's good power (although I think my tune is a little on the over-conservative side). I'm using the same tune file that CobraMarty used from Split Second on my FTC1. I'll need to spend some time tuning it.

A couple of lessons I learned during the install.

1) If you're going to replace the exhaust bolts with studs as Boostwerks did, then you'll need to make sure you get a shorter stud for the 4th lower stud as there is a primary that interferes with that hole on the Gibson headers; you can make it work, but it is a pain and you must use a an open end wrench to tighten. (I fully expect to have to replace this when I get more time).

2) The Power Steering pump bolts are too long for the boostec s/c manifold and will need to be cut down, they're like 90mm and I couldn't find anything longer than 60mm, so I had to cut down what I had and make it work.

I'll post a pic of it finished later, but this was about half way through.

 

[urban yan]

So you'll be retaining the 7th injector? I'm definitely interested to see your progress.

Also -- a little off topic -- are those Brown Dog Engine mounts Rubber or Poly, and if they're rubber are you getting any vibrations coming through?

 

[merdock69]

I'll keep the 7th injector for now; at least until I hit a wall trying to tune it.

They're brown dog rubber. Yes, they vibrate at idle, more than I expected. Not enough for to pull them out though.

I'll update as my tuning progresses.

 

[merdock69]

Well, I've got it putting out 5.5 psi of boost. Still have some tuning to do, but at least she's running and functional again.

 

[merdock69]

I got the wideband w/ narrowband simulator installed. It works great too, still no cel's. The only drawback is I can't view boost & afr at the same time. I have to go back and look at the FTC logs for that.

http://plxdevices.com/product_info.php?id=WDBDSMAFR_DM6

I'm dropping to 11.0 afr at wot with 5.5 of boost. At part throttle it looks as if the ECM is pulling back fuel trim and fighting the FTC to get AFR's back to the 14.5 - 14.7 range. I'll bounce down to 13 when I first start to accelerate from a stop at 1/2 throttle or so, but it quickly flattens out at 14.7 and I feel plateaus in the power, but can't tell if its the fuel or if its the FTC pulling timing yet. I'll need to review the FTC logs to tell.

I have also not moved the MAP sensor input to boost side of the manifold yet. When I do I'll be clamping its signal under boost, this may help me get out of closed loop operation under boost at part throttle and prevent the ECM from interfering and trying to raise the AFR.

 

[CobraMarty]

I have also not moved the MAP sensor input to boost side of the manifold yet. When I do I'll be clamping its signal under boost, this may help me get out of closed loop operation under boost at part throttle and prevent the ECM from interfering and trying to raise the AFR.

This is the problem. Move the MAP to the boost side of the manifold. As soon as it sees boost, it will be in open loop.

 

[CobraMarty]

I'm dropping to 11.0 afr at wot with 5.5 of boost. At part throttle it looks as if the ECM is pulling back fuel trim and fighting the FTC to get AFR's back to the 14.5 - 14.7 range. I'll bounce down to 13 when I first start to accelerate from a stop at 1/2 throttle or so, but it quickly flattens out at 14.7 and I feel plateaus in the power, but can't tell if its the fuel or if its the FTC pulling timing yet. I'll need to review the FTC logs to tell.

This is exactally what should happen because you are still in closed loop and not going into open loop when under boost. It is working correctly but it is not doing what you want it to do. It will not work and do what you need it to do until you move the MAP source to the intake manifold and clamp it. If you move the MAP and it sees boost and you don't clamp it, you will get a CEL.

 

[merdock69]

moving the map sensor to the boost side and clamping at 4.75v helped lower my afr's under acceleration. However, I'm still getting a little bit of surging under acceleration.

more tuning i guess...

 

[CobraMarty]

You need to look at your OBD scanner tool to make sure that when you go into boost or even at 0vacuum you go into open loop.

If it is running rich under boost you can adjust the map table in the split sec. IIRC the fuel map is table B, open it and save it or print it for reference. If you highlight all the '3's' and change/autofill them to 2.5 and them highlight the 1 thru first column of 2.5 and click autoscale, it will fill in all the in between values. Minimum pulse is 1ms and maximum is 3.5ms.
For the timing table A you can decrease the timing retard by highlighting all the numbers and then decrease by 50% and it will refill the table with half the values.

 

[merdock69]

Above should have read "helped lower my afr's under MODERATE TO HARD acceleration, throttle above 50%. However, I'm still getting a little bit of surging under light acceleration, <50% throttle."

It's really only under really light accelleration, and I'm still showing 3-5 in/hg of vacuum when this is happening. I did reset the ECM and am wondering if it is still learning the new fuel trims so maybe I'm feeling a little bit of hunting as it continues to adjust fuel.

I'll hook up to a scan tool and watch the open/closed loop status.

 

[Fringe XVO]

I love it. Merdock...YOU'RE BOOSTED!

Subbed.

 

[CobraMarty]

Oh, at 3-5 in/hg of vacuum the split sec shouldn't be activated. Maybe just give it time to learn.
I drove mine for like a week without the SS hooked up and just stayed out of boost. Maybe that week it 'learned' and balanced out.
Watching the open/closed loop status is really satisfying to see it change at 0vac or 1 pound boost. In and out with the slightest bit of throttle change.

 

[merdock69]

Fringe, the valve body mods really shine now that I have a little more power in front of the transmission. The shifts are all very crisp and fast. I love the way it shifts, and can't imagine how much it would have sucked to have boost and those old sloppy shifts.

 

[Fringe XVO]

Friggin' sweet! I can't stop smiling. I know you can't either, lol.

 

[merdock69]

Also -- a little off topic -- are those Brown Dog Engine mounts Rubber or Poly, and if they're rubber are you getting any vibrations coming through?

I'd encourage anyone considering the brown dog mounts to be very honest with yourself about how much vibration/noise you can put up with in your cabin. This kind of falls in line with the spectre & thor cowl induction kits. I'm starting to think I can't handle it.

At anything above idle it is fine, but man, this 6 cylinder just has a lot of vibration at idle (A LOT!) It's not missing or anything, and sounds/feels completely normal if you stand outside of the truck, but if you're inside it is just loud....

I'm going to explore a little bit to see if I may have a problem or can solve the vibration:


1) I may try loosening the serpantine a tad just to make sure I don't have that overly tight causing some of the vibration at ide.
2) Spray ether around the intake manifold gasket/head immediately after COLD startup to ensure there are no manifold gasket leaks (maybe I didn't get a good seal with the flange sealer).
3) I'm looking for a way to maybe bump the idle to 800 or enrichen it at idle, something to smooth it out.

I hate to ditch the mounts as they're otherwise worry free and indestructible. I replaced the transmission mount as well (almost went with a poly daystar mount, probably glad I didn't).

Any other ideas?

 

[O-Gauge Steamer]

The poly mounts should (might?) "smooth" out after they age a bit. I hated the poly transmission mount when it went in 2 years ago. Either I have gotten used to it or it has delevoped some compliance... But the interior panels are not rattling as bad as they did the first day so I am inclined to think the mount has become a bit more compliant.


As for the belt tension, What I do in my Sprintex installation is to tighten the belt until it just stops complaining about the SC load (rev the engine to bring up boost pressure and compressor load) and then add one half turn of the adjuster. Lock it down and call it good. We do have to run more tension than stock, but as Sprintex did not and do not appear to want to provide a tension spec, I use this procedure. It has worked for the better than a year the compressor has been on board so...


Imagine how my Triumph Spitfire (2.4L I6 Stroker) felt at idle. I used solid aluminium mounts on that one as I needed to stiffen the chassis up. It would shake your teeth out at idle. Did help the suspension though.

 

[merdock69]

Well, tried the Ether (starting fluid) test this morning, there are no vacuum/manifold leaks which puts my mind at ease.

Thanks OGS, the mounts are rubber, but still stiff and hopefully will take on some give (glad I don't have solid aluminum mounts like your Triumph!). Your belt adjustment method is pretty much the same method I used to tension my belt I just kept turning it a half a turn or so until it stopped squealing when I goosed it.

OGS/Cobra, where are your stock IAT sensors? I still feel like part of my vibration is timing related. It actually gets worse when the engine warms up or after I've gone into boost. My stock IAT is located in the manifold in a similar location to the stock location, yet I noticed on boostec's directions it shows it immediately under the TB. I also know that timing from the PCM is directly affected by IAT's, so I'm wondering if having my temp sensor in the boost side of the manifold is giving much higher IAT's and causing the PCM to pull back timing. I think I'm going to move it to where the boostec instructions show it and replace the the boost manifold sensor with another PLX sensor that ties into my digital guage and the split second data recorder.

I have not replaced my stock airbox with a cold air/cowl induction setup since adding the supercharger (my old naturally aspirated one won't fit with the new supercharger), but I'll be doing that soon, that may be part of my problem as I may find my IAT's are "off the charts" high.

 

[merdock69]

I moved the AIT sensor from the boost side fo the manifold to directly under the TB at lunch. Made a huge difference in the idle. There is certainly still more vibration from the brown dog mounts, but it no longer feels like the timing is retarded and it at least feels more or less like it did before the s/c install only just a little more noticable.

It also seems to help my plateuing/surging under non-boosted acceleration a little more. Moving the MAP helped quite a bit and I think when I moved the IAT sensor to the cooler location below the TB it both enrichened the mixture and advanced the timing.

However, now my coolant/operating temperature are quite a bit higher (granted it's 104 F degrees today here in Dallas) my temp needle was dead center the entire trip back from the parts store and would creep ever so slightly when sitting at lights. I am still running the stock air box, so hopefully moving the intake back up to the cowl will bring in cooler air and help bring my coolant/operating temps down a bit.

 

[CobraMarty]

...that may be part of my problem as I may find my IAT's are "off the charts" high.

How high? Readings at 3lbs and at WOT with 5.5lbs boost?

 

[merdock69]

I don't know I don't have a scanner or seperate IAT sensor yet.

I've got an android phone on its way in the mail to run torque on, but until then I'm a little blind having only AFR & Vac. Boost to go off of.