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420ponies

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So, I have made up my mind as to change out my small block to a big block. 427 to be exact. I was going with a LS engine but I do like the Big Block idea as to the torque I can get out of a little massaging of this build. I have most of the parts for this build. Brackets for the alternator, A/C, power steering is about all I need for now. Solid motor mounts, Fitech fuel injection, headers and MSD Ignition is about all the special stuff I'd add. I guess I just need change since I have had this car for 10 yrs now. Don't get me wrong, Have enjoyed the SBC I have had in this car, just looking for something more.

Jim

 

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Congratulations on your decision! Do you have to build the 427? If so, what about making it a 496. You want torque..... Lol. Also, since you drive the car, I would suggest looking into the Chris Alston engine mounts for a Chevelle. Work like a solid but feels like rubber mounts. Either way, good luck on your endeavor.

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Im curious, have you experienced driving a vehicle with a Fitech system? If not you may want to find a car with one and give it a run. Internet advertisements and forum chat aside, In the real world it seems the Fitech systems really fall short of even sedated performance. At least thats what i have experienced. 

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ya.... 496....   I love big blocks...  good for you!... have to change your moniker from 420 ponies to ???  BTW... That jack nicolsen photo cracks me up every time I look at it

 

john

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I have a friend who put FiTech on his 69 small block Camaro.  Overall he's pleased, BUT...the FiTech instructions encourage you to put the system on an engine that is already running and tuned. My friend did a bunch of engine mods, including the FiTech and had a very difficult time sorting through the normal issues of a fresh, modified engine vs the "normal" FiTech/computer/fuel/timing issues.  He's a very talented auto mechanic, but was pulling his hair out. He definitely recommends adding the FiTech (or any fuel injection system) AFTER getting your fresh engine broke in and running properly.

 

Tell us about the 427....I'm a big block guy myself and I (mistakenly) thought I could be happy with the 350 in my Custom. I too, have a 427 being prepped to go in the Monte. I've heard people refer to the 427 as "just a heavy small block" but I beg to differ. The torque of a lightly modified "small" 427 will put a smile on your face even if your accustomed to a 420 HP small block.

 

Welcome to the "Rat" pack.

 

Scott

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Well, the 427 in question was a blower motor my friend had. since he went to 496, I have acquired it for working on his 496 engine. It will have oval port heads with 11:0 compression pistons, Comp. cams .550" lift (flat tappet), roller tip rockers. just a nice 427 with some good bottom end torque.

Jim

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Well, the 427 in question was a blower motor my friend had. since he went to 496, I have acquired it for working on his 496 engine. It will have oval port heads with 11:0 compression pistons, Comp. cams .550" lift (flat tappet), roller tip rockers. just a nice 427 with some good bottom end torque.

Would that be a 292 comp cam? We will be using that cam on our next build. What heads are you going with. 049 781.820? The last engine we did was a 396 with L2242 pistons with 38 CC domes and 820 heads. The 820's are 113 cc chamber. This combo gives us about 10.25 to 1 compression. It has the 280 comp cam. Just got the 396 running again today. Seems the machine shop had a bad batch of valve guide seals and the engine was a little "Smokey". 

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  • 1 month later...

The heads I have are 3964290 heads (closed chamber) with a 101 cc head, 2.060/1.740 valves. I also have a Comp. Cams Hydraulic 280H. I need to find out the specs. of this cam. I'm thinking of a Lunati cam with .550" lift and a 234/244 duration @.050" but will find out from my builder which to go for. I had that Comp. cams profile in '72 Nova with a turbo350 auto. with 4:10 gear and N50"s under the car and it ran a best of 11.90 in the Quarter mile. post-259-0-93319100-1480263543_thumb.jpg 

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This is what happens when you run 3964290 closed chamber heads with open chamber domed pistons. Almost all the valves where hitting the pistons. With the combo they put together I think they were close to 12-1 compression. I think flat tops would of been a better choice!  We have a replacement block and a set of open chamber heads with some small dome open chamber pistons. This engine is going back in a 70 Monte Carlo my son bought while he was home this summer.

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Wow! Sorry for the Carnage. You can put an open chamber head on an engine with closed chamber pistons but not  a closed chamber head on an engine with open chamber pistons. Unfortunately many a person has found that out the same way the engine you have has. Glad to hear you have a new engine and are putting into that nice Monte! Good luck! 

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Thank you. The previous owner had a "Machine Shop" build the engine for him. I saw a video  he took of the engine running with the caption "Breaking in the new cam"! By the sounds of it, something was "breaking"! I feel sorry for him really. He was so frustrated with the whole thing. 

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Looks to me that he didn't check valve to piston clearance. most set-ups with a dome ,or semi dome piston, the intake valve pocket on piston is opened up (fly cut) in to piston .-070"-.080" deeper for valve clearance so this doesn't happen. Ditto of what MC1of 80 said. Good luck with the new "build" . post-259-0-93319100-1480263543_thumb.jpgI hate to do things twice!!

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