If the 455 is a running engine, it's going to make more power then your 307. It wouldn't hurt to put a bigger cam in the 455, just don't over do it. BBO and SBO camshafts are interchangeable, distributors, timing chain and cover, water pump, oil pump and driveshaft, and bellhousing are the same. Use your 307 motor mounts and your swap is a breeze. But your 307 being a '85, that should be a roller cam. But the lifters are .921 diameter instead of .842 like the big block. You will need different headers do to the taller deck height. You can get away with not using the computer, run the carb and distributor from the 455 and pull out the check engine bulb from the dash.
cam question
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OK, so I did find that I drilled .075 holes in the butterflies to add additional air to the .056 I went to on the idle bleeds. Where before I had to screw the idle screw in far enough to slightly open the primaries just to get it to idle about 1200rpm or so, after enlargening [new word?] the idle bleeds to .056 you need to add a little more air to the equation and .075 worked for me. Though I am sure some true QJ geek has an actual equation to properly compute all of this, I started small, .048 and .060 I think, and gradually moved both up to .056 and .075 respectively which allowed me to back the idle screw all the way back out and idle nicely at 750rpm.
And, I found that I went to a set of AU secondary metering rods too. These were used in the 70 W30 and others of that era.
You might want to start by trying to find a couple of spare salvage carbs.
I still have one untouched [9] carb but I won't give it away. Keeping it for a spare.
Will post more as I find more . . .
And, I found that I went to a set of AU secondary metering rods too. These were used in the 70 W30 and others of that era.
You might want to start by trying to find a couple of spare salvage carbs.
I still have one untouched [9] carb but I won't give it away. Keeping it for a spare.
Will post more as I find more . . .
The non swirl port, flat tappet cam 307's have a much less aggressive timing curve in their PROM. The later swirl port ones have 60 degrees plus at part throttle, pretty much unusable. Being an early Vin 9, with I want to say high 40's part throttle timing and the richer calibration, a stock smog 455 may run decent on the stock system. Or just use the 455's stock carb and distributor and add maybe a 215 duration cam, keep it under .500" lift and uses the Cloyes Billet Roller timing set if you are not degreeing the cam. It is supposed to be very accurate.
Well, kinda-sorta. My '87 [9] 307 had a max lean burn mode spark advance of 54 before we tweaked it. Working with a friend up in Toronto I have sadly lost touch with [this whole conversation makes me determined to reconnect with him if nothing else just to see how he is?], we took my BB clear out to 66 max which enabled us to lean the CCC out enough to achieve the 18-20mpg numbers. Of course, this ONLY happens in overdrive + light throttle but it runs great, no ping at all, with no effect on engine temp at all. Otherwise the nominal light throttle spark advance curve is always down in the high 30s to low 50s during normal driving.
54 isn't all that bad, have heard low 60's. I know some have had no issues running BBO on the CCC set up, mostly 442 owners. Other can't get reasonably mild Olds 350's to run right and give up.
took awhile waiting for parts and some junkyard scouring but the 455 is up and running very smoothly=) thank you for the input cannon and olds 307 it was invaluable while drilling out my carb.instead of drilling holes in the butterflies though i opted to drill out the idle bypass passages on my base plate using a 1/16 drill bit,seems to have worked great for me.almost wish i had gone alittle bigger on the cam though i opt3ed for a w-30 clone from lunati but still feels great,still have power breaks and computer is happy.
next project is beefing up the transmission and attempting to fit my headers in for some better flow...couldnt afford w/z manifolds so i just used the stock manifolds.all in all it fit like a glove =)
next project is beefing up the transmission and attempting to fit my headers in for some better flow...couldnt afford w/z manifolds so i just used the stock manifolds.all in all it fit like a glove =)
Though it was also problematic at idle, even the Mondello 230/236 @ .050 cam was a bit much for my computer and also part of our challenge was getting the new cam to behave in lean burn mode on the H/W. So, I pulled it and went back to the Comp 224/230 but with almost the same .496/.512 lift and it purrs [BTW, I no longer see that cam on Comp's website . . . they seem to have gone to flat spec cams]. That W30 cam was quite wild as I recall. Not much lift [.485/.485 or something?] but like [what?] 308/308 duration? Bet it sounds quite mean though . . .
Though it will actually run better with less duration and more lift . . . hey, if it ain't broke?? . . . enjoy!
There is no replacement for displacement!
Though it will actually run better with less duration and more lift . . . hey, if it ain't broke?? . . . enjoy!
There is no replacement for displacement!
ok new issue lol,everything works great at inital startup and then i go to drive,idles great but then i press the gas and soon after it starts idling like crap,good oil pressure but seems like the fuel bowl is emptying to fast maybe?should i of upgraded to a bigger fuel line in the process?
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