The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 71 4x4 BBC Swap: Doing what I should have done the first time!

mtharleydavidson · 02-20-2010, 01:33 PM

Been a while since I had any updates. First off, you were spot on with the Header selection... The 2455HKR fit very nicely, but will require that the engine be raised a bit in the mounts to clear on the drivers side. For me, a 1" lift will solve all my problems. This will allow clearance of the frame rails and clearance in the oil pan. I called Kert at DIY4X and they are fabricating new engine mounts for me that simply add 1" of height to the existing mounts. Should be a simple fix.

I did have a couple of modifications I needed to do to the headers. My 502 BB has ARP head bolts that are pretty tall, so I had to notch the header flanges a bit to clear the lower head bolts. It was either that or use different head bolts but I had a hard time time finding low clearance bolts better than grade 8. I also shortened the collectors about 4" as they were getting pretty close to the T-Case crossmember and I was concerned about the exhaust. passenger side. I added some pics to hopefully show what I am up to... BTW the 2817HKR's were a bag of hurt...
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02-20-2010, 01:33 PM	#105
mtharleydavidson Registered User Join Date: Nov 2008 Location: Bozeman Montana Posts: 9	Re: 71 4x4 BBC Swap: Doing what I should have done the first time! Been a while since I had any updates. First off, you were spot on with the Header selection... The 2455HKR fit very nicely, but will require that the engine be raised a bit in the mounts to clear on the drivers side. For me, a 1" lift will solve all my problems. This will allow clearance of the frame rails and clearance in the oil pan. I called Kert at DIY4X and they are fabricating new engine mounts for me that simply add 1" of height to the existing mounts. Should be a simple fix. I did have a couple of modifications I needed to do to the headers. My 502 BB has ARP head bolts that are pretty tall, so I had to notch the header flanges a bit to clear the lower head bolts. It was either that or use different head bolts but I had a hard time time finding low clearance bolts better than grade 8. I also shortened the collectors about 4" as they were getting pretty close to the T-Case crossmember and I was concerned about the exhaust. passenger side. I added some pics to hopefully show what I am up to... BTW the 2817HKR's were a bag of hurt...