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| | | Forums66 Topics128,095 Posts1,056,480 Members48,444 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Dec 2003 Posts: 61 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 61 | Later this Spring, I will be taking my 61' 235 to the shop to have it cleaned & bored. I was planning to go 40 over, with a Howard cam, solid lifters, and 2x1 intake, dual pipes. This months Classic Trucks has part 1 of a 235 rebuild, going 60 over, I always thought(I can't tell you why), this was too much, if I reconsidered, would 60 over be o.k?. Any significant difference in using either the Fenton or Offy 2x1 intake? I do have the three speed, and previous threads on this have indicated some grinding on the Offy intake so the shift linkage will clear. Is there any concerns with using an aluminum intake versus cast? Thanks for any advice! | | | | | Joined: Apr 2004 Posts: 72 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2004 Posts: 72 | In my opinion you will not see or feel much of a difference between the two over bores you mentioned. Generally the machine shop will recommend an overbore based on the existing condition of the block. If it has been bored before, how much that bore may have been, and how much it will take to "clean up" the bores at this time. Considerations may also be made as to availabliity of pistons you can get. As far as the intakes are concerned. My bet is that there would be little difference between the two intakes you mention. Your best returns for power would be to have the head worked over really well. There are certain heads that will out perform others simply by the nature of the design the manufacturer used with that head. There are the "848" heads for your 235 that are the sought after heads for more performance. If you can afford some porting/polishing work or oversized valves from the stock ones will give you better performance with your hotter cam. Of course you need to take carburation into consideration in the long run also. As to cast or aluminum intakes...generally only the after market intakes are aluminum and the stock OEM intakes are cast iron. After market intakes will be usually two or three carbs. Offenhauser, Fenton, Weiand are a few. There are others but they escape me currently and are more difficult to locate. The Offy intakes are most popular cause they are easier to locate. They are also re-popped type of intakes these days. Some of the others are originals from back in the day so harder to come by. I saw two at a swap just this last weekend here in KC. Both were Offy, one two carb and one three carb. Both older originals with one barrel carbs already on them. I am sure some other guys will add to this topic in good time. Oh and welcome to the bolt too! I hope to see you in Kansas City at the "All Truck Nationals" later on in the year. We had a bunch of "Stove Bolters" here last year and had a good time visiting and such. Make some plans to attend if you can.
52 GMC Suburban...52 Chevy 3/4 ton...49 CHevy 1/2 ton Rod...49 GMC 1/2 ton retro rod project
| | | | | Joined: Mar 2005 Posts: 1,513 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 1,513 | Don’t bore it any more than you have to. Let your grandson (or somebody’s) bore it .060” over and even .080” parts aren’t hard to find. If you’re asking about new, reproduced intake manifolds I liked the Fenton better as the carbs are farther apart than the Offy which allows for 2 oil bath air cleaners. It mated to a stock split exhaust without any grinding or filing and it’s supposed to mount to Fenton headers without modification as well but I can’t verify that. Usually grinding is required to eliminate interference between the intake and exhaust manifolds and not for shifter clearance. I was able to keep my column shift by making modified arms to reach under the intake. I have seen both Offy intakes and Fenton headers on ebay that have been ground right thru and believe milling the header flanges is the preferred method to make that work. The Offy probably has the edge on looks but I’m happy with how well mine fit. Here’s a pic. Patrick’s sells just about everything on your wish list and if you buy it all together you’ll probably get a better deal. Good luck. Curt B.
1952 1300 Canadian 1/2 ton restomod You Tube | | | | | Joined: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | Catman: The previous two posts have pretty well covered the info you asked about and the only reasom I'm chiming in is not to tell you what I have but only to clarify the linkage point. Using the stock lower pivot and rod I had no modification at all to the linkage that came with my intake from Stovebolt Engine Co. I did have to cut one of my shift levers and shorten it to clear the rear of the intake. Perhaps 1/4" is all it needed. I did the grinding business but agree that milling the surfaces to match would have been a better choice. Still looking for proper studs for holding the manifolds to the head.
Overboring could cause some heat issues but I doubt even .080 is enough to cause that. Pistons are availabe in nearly any size for the engine. I did mill the head about .010-.020 to clean it up and raise the compression a bit but mostly to make sure it hadn't warped. Money spent on the head pays a bigger dividend than about anything else you can do.
With your low member number I see you are not a new member so your familiar with the search feature that has a great deal of info on this popular upgrade. | | | | | Joined: Dec 2003 Posts: 61 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 61 | Thanks guys! BigSix302, thanks for the invite! I jumped the gun, you are right about seeing what the shop has to say first, about the bore. Curt, WOW! hope mine looks as half as good as yours! The Fenton does look good. Dave, I had the head done sometime ago, I don't remember the mill(yes it was that long ago!) I will have to look at my receipt. I do use the search feature very much, one reason with the low number, I am still an apprentice. I was just curious if there was more than fit and finish to the intakes. Thank you all so much! Next week it's off the machine shop, and a check to Patricks, and watching e-bay! | | | | | Joined: Nov 2000 Posts: 582 Shop Shark | | Shop Shark Joined: Nov 2000 Posts: 582 | Catman; Just finished the Offy/Fenton challenge with milling and such. I documented a lot of the rebuild in the "Rebuild" album below: http://community.webshots.com/user/geezer | | | | | Joined: Sep 2003 Posts: 324 Shop Shark | | Shop Shark Joined: Sep 2003 Posts: 324 | Catman, you might consider the Holley Webber carbs also. They are a progessive carb that gives you the best fuel mileage and when wide open they will give you plenty of go. I have done this with my engine and love it. Tom | | |
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