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Old 02-16-2007, 12:52 AM   #1
cstm68
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holley 770 on a 327??

is a holley 770 too big for a rebuilt 327 ??
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Old 02-16-2007, 01:11 AM   #2
ProStreet68SB
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Re: holley 770 on a 327??

yeah thats alot for a 327 you'll probably want a 600 or 650cfm carb for a 327
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Old 02-16-2007, 01:14 AM   #3
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Re: holley 770 on a 327??

well ive got 202 heads on it. will that make a difference??
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Old 02-16-2007, 01:27 AM   #4
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Re: holley 770 on a 327??

it will slober all over its self. 600 vacume secondary max. low tension spring in the secondarys. my 327, 350 hp vette engine from the factory only came with a 650 double pumper and its hi-compression with big valves & solid lifters. dont over carb it. make sure you got hard valve seats in the heads........ for sure. there not factory so you,ll have to install them.
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Old 02-16-2007, 02:52 AM   #5
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Re: holley 770 on a 327??

too big......650cfm max IMHO...

I will be running a 650cfm Holley 4150HP on my 327 with Brodix aluminum 200cc intake runner, 23*heads with a comp 286 solid roller cam...
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Old 02-16-2007, 01:10 PM   #6
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Re: holley 770 on a 327??

i am not replying to agree or dis-agree. i believe it was popular hotrodding that had an article about big carbs. several test with near stock 350 and 383 engines using 850cfm and 1050cfm domintor carbs. the main jest of this was with the proper boosters you could maintain good off idle response. seems if you already have that large carb you could do some research and use it.
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Old 02-16-2007, 01:17 PM   #7
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Re: holley 770 on a 327??

I recall that comparison, & on a dyno, if your looking at max #s , I agree with it. However , in the real worlda smaller carb will offer better overall driveability & much more crisp response. Heck Ive got a 770 Holley on my 468.. a 327 wouldnyt need that kind of cfm unless it was going to be reved to well ove 7000 RPMs, in wich case you wouldnt be using that particular carb anyway. 600 CFM is more than enough for most any 327 CI engine to 6000 RPMs. Heck Id even consider a 570 CFM carb for that engine. John
P.S., you can make it run just fine with that carb. I had a 750 on a 305 that ran just fine, but, itll run better over all with a smaller carb.
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