Unfortunately for me, I am going to need the 45 degree down collector on the manifolds as my '65 front clip is not modified.
Of course, I'd heap rather have the 3790729 & 3790730 or 3849288 but the prices for them are HUGE! . As far as I know all
the corvette manifolds had the collector that went straight down so they are no good for me. I read an article that said these
Dormans would fit but the drivers side did not have the front extensions and holes for the alternator . My thinking was if the
trucks would fit I'd relocate the alternator down by using an aftermarket bracket.
Even these Dormans cost to much money to experiment with so I was looking to hear from someone here that has used them.
Certain year truck ones have the 45 and will fit (more or less). Not sure what year though, think it is the 1967 - 72?. The dump sticks out too far and makes getting the pipe connected difficult. There is a member or two on here that have used them. They of course have the wrong alternator mounting as you are aware. The Chevy II alternator mounting is pretty unique.
What is a HUGE price for them anymore? I just don't know the market. Also, it seems that there are a few flavors, including '64-'65 4bbl right side, A.I.R., A/C and non for earlier cars. I would think the A.I.R. ones are a little cheaper for the tube bosses/threaded holes, but I haven't seen a set for sale recently. It's a good start to a thread, and I'd like to hear from members that used ram's horn manifolds from other Chevrolets on 1st and 2nd generation Novas and what are some good casting numbers, both left and right, that will definitely work.
I have them on my 63. They are from a chevy truck ( no year) and did not have the A.I.R. bosses, but it does have the bosses for the alternator which I am using with my setup. .You would need this bracket and of course you can always go with a low mount bracket. Yes, the dorman truck manifolds will fit nicely.
Quality! Thanks for all the info. I'll be cobbling together a budget '63 V-8 swap, and want Nova manifolds, but they may be priced out of the question by now. Can't tell you how many sets of those I've let slip through my hands.
And to answer your earlier question, there were at least 8 different manifolds used between 1964 & 67 per the GM parts book. 6 versions of the right-hand and 2 of the left-hand. By '69 this was superseded down to 4 total and then down to 3 in the 1970s. I have some detailed notes on this, but they are not ready for prime time yet. I suspect there are 1 or 2 more right-hands I need to track down, that for whatever reason do not show up in the parts books.
The parts books I have are contradictory and confusing (big surprise), but at some point it appears the smog with A/C bosses manifold superseded all for the right side. This makes sense, as all the right-hand A.I.R. manifolds I have had in recent memory had the A/C bracket bosses. Much more common.
As for price, $200 - $300 for smog ones, $400 - $600 for non-smog. Condition is everything of course. Most seem to be cracked, repaired or badly pitted by this point in time. The skinny ear loves to break off as do the lower bosses where the pipes mount. I would say 3/4s of the ones I see advertised for sale on the interwebs are not Chevy II.
I have some memory of NNN reproducing them in a small batch years ago, but cannot find anything to back that up.
I hunted around and found this. Is this the bracket you are using? Research says these mount to the water pump and front of intake manifold. There are some exhaust manifolds that these look like they might work with. I have no experience and have been doing a lot of looking to see if there is a manifold that does not have the alternator brace cast to the front of the LH manifold which these might could be used with.
Riverboatman, those will not work with the Dorman ramhorns. If you go with the dorman, which I think would be a good purchase price, you can use a low mount bracket or a bracket that mounts to the head's accessory bosses, provided that your engine has them. I am sure there are other options out there. I started with a low mount, then I added power steering so I went to that bracket that mounts to the manifold, but it is to close to the steering pump fill cap, so I am now exploring the head mount bracket. Also do relize that brackets avialable are for short water pumps and long WP so make sure you explore the correct one. The mounting bosses on the manifolds that I have require a short WP. Good luck.
Jay, when you showed that bracket I got to looking at what was available on ebay. It seems there are some manifolds out there that have the collectors leaning like the Nova manifolds do but no provisions for the alternator mounting. The collector neck seem to be longer than the Gen I & Gen II Novas. There are also some that have the collector leaning back which have the short stubby mounting on the front of the LH manifold (3855183) to use the brackets that I was showing. I think. That was the reason I posted those brackets because they looked like they would fit that type manifold. Of course I can't say for sure.
This whole thing about exhaust manifold for the 1964-67 Novas is very confusing. Especially when trying to piece together a LH-RH set. There are a lot of manifolds available but not for the 64-67 Novas. I will be using the short water pump so that clouds the issue even more.
I was looking at the 1967-72 truck manifolds as a source but have been finding a lot of conflicting comments on the internet about the truck manifolds. Some say they will fit find and other not. One main concern was that the truck manifolds 45 degree collector was made to lean out slightly because there was more room inside the truck frame and to help stop interference with the starter. Whereas, the Nova manifold collectors leaned in a little more because of the frames being so close to the exhaust pipes. I can't prove that. Just repeating what I read on another Nova site. Maybe someone that has an engine installed in their Nova that is using the truck manifolds can post a photo of the clearance in those areas.
I have found that if I am going with the GM manifolds then the '65 Nova non-A/C manifolds would most likely be the 3790729 LH and the 3890424 RH manifolds with the 424 manifold having the heated air type choke system.
But there were also some Novas delivered with the 3790729 LH and 3790730 RH combination. I haven't found out any info as to why they changed the RH from a 424 to a 730 manifold except I do know the 730 was mounted on a 2 barrel 283 engine which had the divorced choke setup on the intake manifold.
The GM 3849288 exhaust manifold from a 64-67 327 is suppose to fit. I haven't seen a 288 manifold that has the heated air choke tubes installed so I have to assume those manifolds were used on engines that had either divorced or 12 volt choke systems.
The following is a list of manifolds that are suppose to fit the 283, 327 and 350 engines: 3780728, 3790729, 3790730, 3791130, 3849288, 3849290, 3872723, 3872738, 3890424. Please tell me about any part number that you think is not correct. This info came from: Chevy Exhaust manifold Identification - Chevrolet Ramhorns
I'm sure there are many guys that would like to get all the facts about what will work and what will not. I'm wanting a nostalgic look so using the rams horn exhaust manifolds are what I am going after.
The 1964 - 67 Chevy II V8 exhaust manifolds have a collection of features that make them unique, the main ones being the alternator mounting and the tight 45 degree dump. Most rams horn manifolds will fit, the issue becomes running the exhaust pipe to the collector. The 45 degree truck ones are supposed to be the closest, but the dump flares out and can cause clearance issues. Results will vary based on the talent of your exhaust shop.
I am still working on compiling my Chevy II exhaust manifold notes, but below is what I have compiled over time (I do not consider it 100% complete). None of this is sourced from online resources. It is all from original GM literature, manifolds I have in my possession or info from very trusted sources. I will inevitably post a finished version on my website and hopefully with pictures of most manifolds.
There are no "327" or "L79" manifolds. I have an engineering schematic that indicates the internal dimensions never varied with the Chevy II exhaust manifold through the 1964 - 67 run (as it did with other Chevrolet's). Manifold changes were based on the presence of A/C (C.A.C.), A.I.R. and the choke setup of the carb. The latter seems to only come into play with 4bbl 283s. As time went on manifolds were superseded and narrowed down to just a few.
## Non Smog (Common) ##
1964 - 66 -- 3792290 - RH (exc. 283 4bbl)
1964 - 67 -- 3790729 - LH (disc. 12-1981)
1964 - 66 -- 3849290 - RH w/ 283 4bbl || 1967 All (exc. A.I.R.) [This is the original '64 V8 manifold per '63 parts book]
Alrighty then. Hopefully this added some semblance of sanity to what all GM was doing when they changed all the
manifolds and their designs. I'm plumb bushed what with all the searching I've been doing online. If anyone else
would like to chime in, go for it. The more input the better is what I always say.
I'm not through yet. I've got a few questions about distributors coming next so stay tuned. I need some help with that
South Bay is correct, any good exhaust shop can deal with the minor differences in the angle of the manifolds which I think would only vary slightly from 45 degrees. I got mine from a junk yard chevy truck and I think it was a 60's truck. I have had no problems with my manifolds and I have replaced steering box, brake vacuum booster, changed plugs, without having to remove the manifolds or down pipe. No problems on the passenger side either and I have the stock starter. If you want pics of the bracket or how thinks fit around the manifold and down pipe I can send some to your private box. .Send me a private message..
I have a different question, I have the 3790729 and 3849290 manifolds. The RH one has a hole drilled (?) that goes right thru the top into the exhaust path and the LH one has a hole drilled (?) under by the connection to the rest of the exhaust. Is this correct? Why would they be there? I have not actually put my hand there to feel exhaust coming out, but I did stick a pipe cleaner in it and it went it all the way!