I put my old LIM back on...
#1
Senior Member
Certified Car Nut
Thread Starter
I put my old LIM back on...
... because ZillaMotorsports ported it for me.
I didn't take any pics because... well... I've seen it all before fairly recently. I'll go get a key shot here in a few minutes.
I'm feeling better mid-range power, the kind that rips the tires loose when you mash it and it downshifts to first. My test drive speeds were pretty limited, so I can't tell you about top end power just yet.
I didn't take any pics because... well... I've seen it all before fairly recently. I'll go get a key shot here in a few minutes.
I'm feeling better mid-range power, the kind that rips the tires loose when you mash it and it downshifts to first. My test drive speeds were pretty limited, so I can't tell you about top end power just yet.
#3
Junior Member
Posts like a Ricer Type-R
Center of the pic here (between two nosedrives):
Bottom right here (custom laser engraving on the bypass cover):
The work included some corrosion pitting repair around the coolant ports. All in all, it was in pretty good shape to begin with.
If history repeats itself, it'll really come into it'* own in about 100 miles as the PCM learns it. Glad you like it, and I wish I'd turned it around quicker.
Bottom right here (custom laser engraving on the bypass cover):
The work included some corrosion pitting repair around the coolant ports. All in all, it was in pretty good shape to begin with.
If history repeats itself, it'll really come into it'* own in about 100 miles as the PCM learns it. Glad you like it, and I wish I'd turned it around quicker.
#5
Your PLIM makes me extremely jealous.
I need to get my *** out to the U-pull it to grab the LIM off a 92 PA Ultra there, and get it shipped out to ZiLLA Motorsports!
I need to get my *** out to the U-pull it to grab the LIM off a 92 PA Ultra there, and get it shipped out to ZiLLA Motorsports!
#7
Originally Posted by sandrock
I got one....
Completely useless to me now :?
But dammitman...that car felt hella quick before it played the tune "pop goes the piston".
Completely useless to me now :?
But dammitman...that car felt hella quick before it played the tune "pop goes the piston".
#8
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I got no pics of the porting...got installed pics left and right though. My OBD2 thread has a few money shots.
But this is now starting to turn into hijack...so to turn it back around...Wren, did you open up just the ports and the coolant passages (I KNOW you did that much), or did you also include the SC inlet area?
But this is now starting to turn into hijack...so to turn it back around...Wren, did you open up just the ports and the coolant passages (I KNOW you did that much), or did you also include the SC inlet area?
#9
Junior Member
Posts like a Ricer Type-R
Re: I put my old LIM back on...
Originally Posted by J Wikoff
I'm feeling better mid-range power, the kind that rips the tires loose when you mash it and it downshifts to first.
http://www.bonnevilleclub.com/forum/...ic.php?t=97624
You'll notice in that topic the VERY good alignment of the LIM to the head ports on install. If you don't have your motor opened up during porting, you'll need to rely on very good experience to keep the port spacing right (based on port-port centroids). This is critical to maintain equal port velocity across all 6.
If done correctly, a very noticable midrange pull will be felt. It may or may not raise the HP peak, but it gets into it quicker through the midrange, 'flattening' the HP curve a bit, and provides a much improved throttle snap (response) off the line. This is true for SC or NA LIM'*.
Remember, the WORST from the factory, and gains the most is the L36.
Next is the S1 L67 (and L27).
The best from the factory is the Series 2 L67. This gains the least matching to factory heads, but if you don't mind 30 minutes of cleanup, you will notice it.
There are great variances in match from LIM to LIM of the same type. As well as casting flaws that push one cylinder 'out' a bit compared to the rest on some LIM'*.
There is a little more spooky detail work you can do with the PROPER precautions before installation. AFTER insuring a good port match on the LIM, you'll be left with the ideal dimensions of:
LIM.......0.85x1.85" with corner radius matched to head ports (improved to ~1/8")
Heads...0.90x1.90"
This STILL leaves the gasket cavity at 1.0" by 2.0" (roughly) causing a small mismatched cavity between where the AF mixture can swirl, eddy, and start to expand before necking back down into the head. This can be improved by LIGHTLY chamfering or rounding off the entrance of the cylinder head port. EXTREME caution should be used if this is done with the heads on the car. Stuff the ports, tape everything off, and have a good shopvac and magnet ready for each port. An exaggerated detail I worked up in CAD:
This is the original concept I worked up a couple years ago.
Refined to the dimensions I port to now (and stated in this topic) it would be this AFTER porting BEFORE chamfer:
AFTER porting and AFTER chamfer:
Think of it as not much more than smoothing off the sharp entrance to the cylinder head intake port to ease the transition and maintain port velocity. This has been done on several cars with great success, including the two shown in the link above from this weekend'* work at my house.
DISCLAIMER:
I'm not responsible for a anything you screw up on your car, and I'm warning you now that if you've never done this before, do it the first time with someone who HAS, and has also DEMONSTRATED success with it.
#10
Junior Member
Posts like a Ricer Type-R
Originally Posted by sandrock
I got no pics of the porting...got installed pics left and right though. My OBD2 thread has a few money shots.
But this is now starting to turn into hijack...so to turn it back around...Wren, did you open up just the ports and the coolant passages (I KNOW you did that much), or did you also include the SC inlet area?
But this is now starting to turn into hijack...so to turn it back around...Wren, did you open up just the ports and the coolant passages (I KNOW you did that much), or did you also include the SC inlet area?
FYI, in the pics above, LIM is blue, gasket is gray, head is green.