KDG LIM porting
#1
Senior Member
Posts like a 4 Banger
Thread Starter
Join Date: Mar 2007
Location: Brookfield WI
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
![karldergrosse is on a distinguished road](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Hello all. Been a long time since I posted. I was there at the beginning of the LIM porting research. I had just bought a used 99 bonnie sle and wanted to have some fun with it. The Lim porting caught my eye and decided to do it having done the same thing on an import with great results. After tediously completing the job I ran into a serious problem. Many of you know during my "butt" dyno the lower end of the engine blew. I am happy to say it had nothing to do with the LIM porting I had done or the reisnstallation process.
The lower end of the engine simply blew, that'* it. There was no coolant in the oil, no crack in the LIM and no improper reinstallation procedure. Just bad luck. Now looking back I'm happy it happened. I had been spending way to much time playing around with the car. I just wanted a daily driver with spunk and started to get to caught up with it all.
Now this last statement applies to me, not to all of you. Now on to the technical stuff.........
I stand by my procedure of LIM porting and highly reccomend it to anyone. Reason...... After the engine blew, I freaked out thinking it was something I had done. I only had the car for 20 days after purchasing it from a used car dealer. I decided to go after them for the blown engine. After all was said and done they ended up paying half of the remanufactured engine rebuild. I ended up payin 1500. I had gone to a boneyard to get an LIM from an L36 to have them install that instead of the ported one thinking I screwed up the porting somehow. They just replace the short block and bolt on everything else from the previous engine. After reviewing all the work I did on my LIM I decided to have them install it instead. I'm a journeyman machinist by trade and have confidence in my procedures and didn't see how the work I did on my LIM could've blown the lower end.
My instincts turned out to be right. I went to look at everyhting after they had the motor torn down and there was no evidence of what I did porting the LIM caused the lower end failure. That is why I had them bolt my ported LIM on. I know 1500 may seem steep but it came with a 30,000 mile gaurantee and the car is rust free. I will drive it until it dies.
Performance: The reason I took so long to post again was to see if there would be significant "butt" dyno gains and to confirm there is no problem with my LIM. 5000 miles later I am happy to confirm ........This is one of the best if not the best upgrades we can apply to our L36'*. I will note I also gutted the airbox adding my own mods to completely seal off the engine chamber and all I can say is WOW!
These two mods: LIM porting and gutting the airbox are the most cost effective mods for our cars. A word to the wise, folow Wren'* advise when porting and you'll be a happy camper.
If you want to see my methods of LIM porting (and the disaster that ensued) search for: KDG lim porting. Take care all.
Chuck
The lower end of the engine simply blew, that'* it. There was no coolant in the oil, no crack in the LIM and no improper reinstallation procedure. Just bad luck. Now looking back I'm happy it happened. I had been spending way to much time playing around with the car. I just wanted a daily driver with spunk and started to get to caught up with it all.
Now this last statement applies to me, not to all of you. Now on to the technical stuff.........
I stand by my procedure of LIM porting and highly reccomend it to anyone. Reason...... After the engine blew, I freaked out thinking it was something I had done. I only had the car for 20 days after purchasing it from a used car dealer. I decided to go after them for the blown engine. After all was said and done they ended up paying half of the remanufactured engine rebuild. I ended up payin 1500. I had gone to a boneyard to get an LIM from an L36 to have them install that instead of the ported one thinking I screwed up the porting somehow. They just replace the short block and bolt on everything else from the previous engine. After reviewing all the work I did on my LIM I decided to have them install it instead. I'm a journeyman machinist by trade and have confidence in my procedures and didn't see how the work I did on my LIM could've blown the lower end.
My instincts turned out to be right. I went to look at everyhting after they had the motor torn down and there was no evidence of what I did porting the LIM caused the lower end failure. That is why I had them bolt my ported LIM on. I know 1500 may seem steep but it came with a 30,000 mile gaurantee and the car is rust free. I will drive it until it dies.
Performance: The reason I took so long to post again was to see if there would be significant "butt" dyno gains and to confirm there is no problem with my LIM. 5000 miles later I am happy to confirm ........This is one of the best if not the best upgrades we can apply to our L36'*. I will note I also gutted the airbox adding my own mods to completely seal off the engine chamber and all I can say is WOW!
These two mods: LIM porting and gutting the airbox are the most cost effective mods for our cars. A word to the wise, folow Wren'* advise when porting and you'll be a happy camper.
If you want to see my methods of LIM porting (and the disaster that ensued) search for: KDG lim porting. Take care all.
Chuck
#2
Junior Member
Posts like a Ricer Type-R
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Chuck, the only way LIM porting could have blown your motor is if you ported out the ports so far that it 'voided' the LIM gaskets and allowed coolant ingestion. ![Laughing](https://www.gmforum.com/gm/images/smilies/icon_lol.gif)
Glad you're happy with it. Every member here who'* done it has really enjoyed it. Although I find it hard to imagine what you felt was a good comparison, having not driven the car in so long to have something to compare to. My bet is your butt was just damn happy to have a kick in it after waiting for the car for so long.![Wink](https://www.gmforum.com/gm/images/smilies/wink.gif)
The ported LIM is the best bang for your buck for the L36, assuming you do the work yourself and only have to pay for gaskets. It'* far more effective than a gutted airbox or high-flow Cat, but really does go hand-in-hand with those mods. The difference is remarkable, but primarily because the factory port quality (casting) is so very poor to begin with on the L36.
![Laughing](https://www.gmforum.com/gm/images/smilies/icon_lol.gif)
Glad you're happy with it. Every member here who'* done it has really enjoyed it. Although I find it hard to imagine what you felt was a good comparison, having not driven the car in so long to have something to compare to. My bet is your butt was just damn happy to have a kick in it after waiting for the car for so long.
![Wink](https://www.gmforum.com/gm/images/smilies/wink.gif)
The ported LIM is the best bang for your buck for the L36, assuming you do the work yourself and only have to pay for gaskets. It'* far more effective than a gutted airbox or high-flow Cat, but really does go hand-in-hand with those mods. The difference is remarkable, but primarily because the factory port quality (casting) is so very poor to begin with on the L36.
#3
Senior Member
Posts like a Northstar
Join Date: Mar 2007
Location: Minneapolis, MN
Posts: 509
Likes: 0
Received 0 Likes
on
0 Posts
![Barry is on a distinguished road](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Thanks for that update. I have a 99 SSE with 107,000, and intend to port the LIM when I do the gaskets in the spring. (It'* stored for the winter). I have had no problems, but wanted to do the gaskets and replace the UIM just as a precaution. Anyway, I had followed your post and subsequent problems and it did raise a concern with me. I am glad you updated us to confirm it was not the porting that caused your engine failure.
![Wink](https://www.gmforum.com/gm/images/smilies/wink.gif)
#4
Junior Member
Posts like a Ricer Type-R
![Default](https://www.gmforum.com/images/icons/icon1.gif)
In reality, porting the L36 LIM is just making it the way it was originally intended. L27'* and Series 1 L67'* can use some 'cleanup' and mild porting to match them to the heads, and Series 2 L67'* are even closer. The castings for the L36 LIM'* are just a lower quality probably due to production volumes. The ports were INTENDED to actually be rectangular.
They just ended up being something out of a b-rated horror movie instead.
They just ended up being something out of a b-rated horror movie instead.
#5
Senior Member
Posts like a Camaro
Join Date: Oct 2006
Location: montreal canada NEBF07 ONBF07
Posts: 987
Likes: 0
Received 0 Likes
on
0 Posts
![firebuick is on a distinguished road](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
well i ported mine last winter at the same time as a few here because i was going to do my lower gasket anyway and im glad of the result i have a L36 whit basic mod that running good and i get the same 33 miles per gallon as before but whit much more power
#6
Senior Member
Posts like a Camaro
Join Date: Jun 2007
Location: Chambersburg, Pennsylvania
Posts: 882
Likes: 0
Received 0 Likes
on
0 Posts
![putertopia is on a distinguished road](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
I ported mine... I'm very happy with it. It didn't ALWAYS feel like I got AMAZING gains, but that'* because of the dumb mismatched transmission. There was two times I hopped on it after I ported, and I got those wierd tinglies throughout my body that you get after you do something very well, and it makes a very positive difference. Very similar to the feeling you get after hearing 3 - 15" MTX subs hooked up to a 1500watt amp with caps and all.
Glad to hear that your LIM wasn't the cause of death for your 3800. Maybe that'* why the dealer got it - somebody heard/felt some stuff that didn't feel normal and decided it was time to trade her in. Everybody does it.
Glad to hear that your LIM wasn't the cause of death for your 3800. Maybe that'* why the dealer got it - somebody heard/felt some stuff that didn't feel normal and decided it was time to trade her in. Everybody does it.
Thread
Thread Starter
Forum
Replies
Last Post
Speedster400
Performance, Brainstorming & Tuning
6
11-07-2007 09:51 AM
agrazela
Performance, Brainstorming & Tuning
20
02-02-2007 01:04 PM