Inliners International Forums General Discussion Hi Performance 292 split manifold?

Is anybody running one of these that might have a picture I could look at for a guideline or are they as notorious for cracking as I have heard and not worth the effort? Is the heat box arrangement similar to the earlier engines? Thanks for replies.

In the long run you may be best off getting a set of Tom Langdons cast manifolds. The cracking is usually the result of poor welding and preperation.

Hopefully you are right that this subject is shunned simply due to poor fabrication which I do not believe to be an issue in my case. My reasoning for not just buying headers is that I live in the northernmost major city in North America and have summer climate conditions similar to winter ones for those in southern states. When driving my truck to work in summer I reach operating temperature at the same time I arrive there and shut it off. Without a working heat riser setup I would have to nurse it to avoid the dreaded bog and if it’s no fun to drive I would probably just leave it at home. A buddy is planning on a 292 build who will be under the same climate conditions and has asked me for a manifold which is why I raise the question. If there are any reasons that is a poor idea other than the fabrication I sure would like to know.

You can always use water to heat the intake manifold,. there are some threads about this in this forum. By splitting the exhaust, won't you also cut the heat by 1/2 to the intake?

I think a split would work just fine for you. I'm in west central IL. and I have beem split many chev. manifolds and not one has complianed about not enough heat in winter. I have yet to have one crack. I think if you get a repituable welder you will get along just fine. Make sure to put a plate in in it to seperate the 2 sections or you won't get the rapping sounds sixes are famous for. 1 OL REDNECK

Curt,

I have been running a nicely modified 1970 292 for about ten years. I am using Tom Langdon's newest cast exhaust manifolds, his water heated plate for manifold heating. I have not had any leaks, loose parts or starting problems. I used to live in Wisconsin for 7 years and ran my car only when there was no salt on the roads. I now live in the Dayton, OH. area and it does get hot and cold here. Last year, I installed a Vintage Air, Heat and Defrost system. The cooling, defrost and heat work as fast and as well as any brand new vehicle. With proper radiator, thermostat and plumbing, I see no problem using tried and true parts rather than a "Homebuilt" system. I have nothing against do-it-youself jobs as I often invent one offs and do it myself. When reliability and ease of assembly comes into play, it's usually better to listen to experiance rather than experimentation. Isn't that why you are here and asked the question in the first place?
If you need photos, I'll be happy to send you what you need. Just ask.

RapRap
1940 ChoppedChevyCoupe

Thanks for the input. Experience with the older ones is what leads me to be willing to experiment and a friend/welder enjoys the distraction of some old school stuff. It looks like a front dump would be easiest but is there a motor mount or other issue anywhere there? Working around those fins on the rear would be a bit more labor intensive but maybe that’s the only possible position for reasons yet unknown. If it’s an ineffective idea I’ll suggest he use Langdon’s headers but if it works as well as my method of using a gasfitters elbow on the older manifolds I may give it a try. I documented the process I used here and have been successful with both header and blockoff style so possibly someone will find that info useful. I guess I’ll blame CNC Dude for my “if you don’t try you won’t know” outlook lately and if anyone knows of any interference issues please let me know.

Listen to CNC Dude, he knows what he's talking about. He's helping me out as we speak on some Laser cutting. A very knowledgable and skillfull Inliner.
Try anything once and you'll end up leaning like I did. The best way by making some mistakes!

RapRap
1940 ChoppedChevyCoupe

In the day you did what you had to do. There were either few options or few dollars. A split manifold is not expected to give the same performance as a good set of headers, but they can improve performance and make a cool noise. If the welding/brazing is quality work you should have no problems. At any rate if it works for you, where you live, it will work for all of us! Go for it and keep us informed!