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Old 06-02-2014, 05:19 PM   #1
kiles_2001
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BBC 454 question????

so I have a low mileage 454 that came with my truck... the guy told me it was rebuilt but after taking the heads off you can tell it had some miles on it but still very good, the cylinders have no ridge/lip cut out on them yet, the engine has been rebuilt at least once since the pistons are .030 over, they are flat tops with two small valve relief cutouts, the cylinder heads are 049's and that is where my question comes in... I have read in a few places tat flat tops with 049 heads will give me a low compression, will that equal low power? and also what camshaft would be good for it running a TH400 and 373 gears in the rear? any help would be highly appreciated...
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Old 06-02-2014, 08:46 PM   #2
hugger6933
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Re: BBC 454 question????

As long as your not looking for pro mod type power, check out the Comp Cams 268H high energy cam I have run dozens of them small and big block. They sound mean as a hornet and increase the vacuum and MPG in most cases when you can keep your foot out of it. As far as the Compression the later bigs had very little like 7:8 to 1 try a steel shim head gasket to raise it up some or get some older closed chamber oval ports. What ever you do don't get any rectangular port unless they are for trading fuel they will be WAY to big to run on the street with that combo and it won't flow well until way up in the rpm range. Jim
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Old 06-02-2014, 08:46 PM   #3
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Re: BBC 454 question????

Enjoy your tire shredding torque!!!
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Old 06-02-2014, 09:36 PM   #4
kiles_2001
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Re: BBC 454 question????

I would be very happy with torque... I am just worried about the low compression robbing me blind of power... what kind of results can I expect with the combo I have?
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Old 06-02-2014, 09:36 PM   #5
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Re: BBC 454 question????

Sounds like the same set up as mine. Flat tops. 049 heads. I added a comp XM270H marine cam with rpm performer intake and a 770 holley avenger carb. Nothing else was done to the engine. No headers, stock manifolds.

I put down on the dyno to the rear tires 342 RWHP/379 RWTQ.

Shreds the tires with no problem and I have a 3.08:1 rear gear.
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Old 06-02-2014, 09:46 PM   #6
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Re: BBC 454 question????

My cam is an XM270HR. .218/.224 @ .050 with .510 lift. Idles nice. Good vacuum for power brakes. I am quite happy with the performance of the engine. Runs nice and smooth with a slightly loud bbc sound.
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Goldilocks the "Ol School Survivor" 1968 C10, SWB Stepside, 08/15 TOTM, 250 CI 6 cylinder, 3 on the tree, 3.73 rear, 3/5 static drop, 23,500 original miles.
Samson the 1970 CST10, LWB, 462Ci, Turbo 350 tranny, 3.08 rear gear, PB, PS, A/C, AM/FM, 2/4 Drop.
Brutus the 1998 Camaro Z28, 33,500 original miles, LS1, 519 RWHP/497 RWTQ.
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Old 06-02-2014, 09:57 PM   #7
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Re: BBC 454 question????

If you've removed the head anyway, CC the head and the dish. Cheap stuff to buy, fun skill to learn, and then you won't have to guess.
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Old 06-03-2014, 02:58 AM   #8
kiles_2001
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Re: BBC 454 question????

is there a small chambered head with big intake runners I could use to boost my CR??? like some 396 heads?
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Old 06-03-2014, 07:21 AM   #9
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Re: BBC 454 question????

Yes the closed chambers but the runner volume is large enough for what your doing, you don't need 360cc intake runners or anything like that for the street or your bottom end is gone. Trust me have I ever told you wrong?Ever? One thing you can do is shave some CC off your heads to gain some compression just be careful that if you go too far you may need the intake bolt hole slotted or the sides of the intake ground to offset the heads. I have done that on a big block I had in my Chevelle bracket motor. you can gain some that way as well. Jim
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Old 06-03-2014, 01:43 PM   #10
kiles_2001
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Re: BBC 454 question????

I found these heads they are 396 heads 702 casting freshly rebuilt, the guy will take $350 for them, my only concern is the stock valves, I would hate to put in new bigger valves since they were just rebuilt, any suggestions? and yes it is just a street engine I want to hot dog on the streets and rip the tires up every now and then... any info/advice is appreciated.

http://sfbay.craigslist.org/eby/pts/4498326296.html
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Old 06-03-2014, 03:21 PM   #11
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Re: BBC 454 question????

Quote:
Originally Posted by kiles_2001 View Post
so I have a low mileage 454 that came with my truck... the guy told me it was rebuilt but after taking the heads off you can tell it had some miles on it but still very good, the cylinders have no ridge/lip cut out on them yet, the engine has been rebuilt at least once since the pistons are .030 over, they are flat tops with two small valve relief cutouts, the cylinder heads are 049's and that is where my question comes in... I have read in a few places tat flat tops with 049 heads will give me a low compression, will that equal low power? and also what camshaft would be good for it running a TH400 and 373 gears in the rear? any help would be highly appreciated...
The magic in making power in these engines is in the heads. A set of LS6 heads will make that engine more robust without a cam change but combining a new set of heads with a new cam well make your truck stand up and do the tango. As for a cam change only, well, not so much.
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Old 06-03-2014, 04:13 PM   #12
MARKDTN
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Re: BBC 454 question????

Do you have a running engine in the truck and this is extra or was the truck a non-running project and you are have all the BB accessories already?
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Old 06-03-2014, 04:46 PM   #13
kiles_2001
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Re: BBC 454 question????

it was a non running truck when I bought it, I am just getting around to star working on it...
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Old 06-06-2014, 09:19 PM   #14
kiles_2001
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Re: BBC 454 question????

SO...... I bought a set of rebuilt 702 heads... I pulled the timing chain cover and found what I think is a Pete Jackson gear drive, why I think that? it has PJ stamped on it, can anyone confirm or tell me otherwise? also I pulled the cam and found EDELB 2162, so a performer plus camshaft and what should be a new set of lifters to match it, it has some very crappy looking roller aluminum rocker arms that dont even have a brand stamp on them, I was thinking of replacing the push rods and lifters for a set of stamped comp roller tips and push rods
RP1411-16, any suggestions on that? other than that I have a Weiand Stealth Intake Manifold 8019, MSD HEI distributor, holley 770 cfm street avenger and headman headers... I think all and all it is a pretty decent combo, I would really like to hear from anyone as far as the cam goes, the rpm range for my intake matches but my concern is I have never heard anything good about edelbrock cams... a while back I did hear bad things like premature wear and that they arent really performance cams, can anyone elaborate on that? thank you in advance fellas...
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