Jesse_Wenting
Old Thread Reviver
Literally just following this for the pictures lmao. Great info though 
99 L29 454 build
- Thread starter Scottm
- Start date
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Almost finished with the intake manifold. I matched the top and bottom halves to the gaskets, cleaned up around the inlet and IAC port, and narrowed the divider vanes in the runners. Getting way down in there with long burrs is hard, they really jump around...
I'm also thinking about how to keep intake air temp down. There are good reasons why the factories are using plastics for manifolds lately. The L29 mani is a huge aluminum box, being heated by oil on the underside and by hot air under the hood. I have noticed a loss of power when towing and climbing hills in the summer, sometimes down to 35 in second gear. Could it be related to the reduced intake air density of hot air? Maybe a reduction in ignition timing due to hot air bringing on ping/knock?
I'm going to start with a thick coating of engine paint on the outside to hopefully add some insulating effect, and make a oil deflector for the underside. I'm thinking of painting the inside of the mani too, maybe with Glyptal or an epoxy sealer of some kind. I think it will make the inside smooth for airflow and add resistance to carbon formation, but also maybe an insulating effect too. While the old engine is still in and driving, I want to put a temp sensor in a manifold runner to see the before conditions, then put the same sensor in the new engine.
I'm also thinking about how to keep intake air temp down. There are good reasons why the factories are using plastics for manifolds lately. The L29 mani is a huge aluminum box, being heated by oil on the underside and by hot air under the hood. I have noticed a loss of power when towing and climbing hills in the summer, sometimes down to 35 in second gear. Could it be related to the reduced intake air density of hot air? Maybe a reduction in ignition timing due to hot air bringing on ping/knock?
I'm going to start with a thick coating of engine paint on the outside to hopefully add some insulating effect, and make a oil deflector for the underside. I'm thinking of painting the inside of the mani too, maybe with Glyptal or an epoxy sealer of some kind. I think it will make the inside smooth for airflow and add resistance to carbon formation, but also maybe an insulating effect too. While the old engine is still in and driving, I want to put a temp sensor in a manifold runner to see the before conditions, then put the same sensor in the new engine.
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454cid
Sooper Pooper
Instead of trying your own ideas on coatings for heat, why not do a search for professional applications of heat coatings that will be proven? Isn't Glyptal pretty expensive as it is.... at least considering it's something you paint on with a brush.
That intake looks great..... I wonder what mine looks like. I've never taken it off myself.
That intake looks great..... I wonder what mine looks like. I've never taken it off myself.
Supercharged111
Truly Awesome
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Save your money from fancy coatings and put it into a tune instead. The stock tune is pathetic.
94K3500PROJECT
I'm Awesome
I didnt see any flow numbers before and after swirl ramp removal did you get those?
Starting to kick around the idea of a 454 swap
Starting to kick around the idea of a 454 swap
Beeffajitas
OBS Enthusiast
IATs pull timing. The whole intake tract heat soaks, especially when you're stopped. I've been wanting to experiment with some well placed louvers to aid with heat extraction but I haven't got around to it.
I'm all in on the 0411 swap. I ordered one on ebay loaded with the 01 van vin that Supercharged posted in the base tune thread. I also got a red and blue connector set coming from ebay. Today I bought another connector pair and an obd2 port at a local yard to make a bench tuning harness, like this yt video:
Wrecking yards won't cut up a complete harness, so I had to find a damaged one to get just the connectors. I could only get blue and green connectors. I hope the only difference is the position of the guide ribs on the colored plastic. If so I will grind the ribs off the green one and just hope it's willing to self-identify as a red..
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Wrecking yards won't cut up a complete harness, so I had to find a damaged one to get just the connectors. I could only get blue and green connectors. I hope the only difference is the position of the guide ribs on the colored plastic. If so I will grind the ribs off the green one and just hope it's willing to self-identify as a red..
Attachments
L31MaxExpress
I'm Awesome
The green connector fits perfectly after grinding off the tabs although I have a stash of all 3 these days. The yard I frequent butchers harnesses anyway. I bought 4 of the Green/Blue P59 PCMs with IAC drivers and analog a/c input with the connectors yesterday for $35 each. 2 came out of 2003-2005 DBC Express vans and 2 came out of DBC 2003 Tahoes. The 2003 4.3 van one I bought is getting swapped into my buddies S10 Blazer with a turbo 4.3. I have a 350 that is going to run with one. More than half the trucks there had 0411s including a couple 01-02 van ones that already had the right pcm file to run L31s. Yard probably had 100 LS PCMs.
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