CK5
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Big block guys
- Thread starter 85 Jimmy
- Start date
And since @Greg Ducato has already stepped in here, what needs to happen with my 700r4 to make it live?
It's a TCI maximizer that I got new around 10 years ago. Right now the cooler is just the stock one in the tank of the radiator, it has a deep 6 quart finned aluminum pan, and it also has just a stock 350 converter in it. Other than that, it's the way TCI built it.
It's a TCI maximizer that I got new around 10 years ago. Right now the cooler is just the stock one in the tank of the radiator, it has a deep 6 quart finned aluminum pan, and it also has just a stock 350 converter in it. Other than that, it's the way TCI built it.
I think your foot is going to negate any positive mileage effects you get from switching. Also, will a 454 beat out a small block for mileage if the gearing isn't raised to keep the engine speed down? I was thinking that you had to be doing low-end torque stuff to beat out a small block for mileage. I can find lots of examples of people who lost mileage when swapping to bigger engines.
Just in case it's worth anything, my brother's getting 7.5 or 8 with his quite badly-tuned Q-jet 454/TH400 rig. But that's a 15,000lb motor home, and it moves pretty slowly.
I get 25 mpg with my BBC and TH400. Yep. In my dreams.
My '85 K30 with a mildly built 454 gets 5 mpg no matter what. That's why it sits in the shop resting peacefully.
My '85 K30 with a mildly built 454 gets 5 mpg no matter what. That's why it sits in the shop resting peacefully.
I say try it and see how it works.... Because big blocks are FLIPPIN awesome
I may build it and put it on an engine run stand to piss off the neighbors. Then when I'm ready to swap it, put the 350 on the run stand and continue to piss off the neighbors!
Haha nice!!! I live between 2 railroad crossings, both my neighbors are deaf old people, there's a gun shop across the street, and next to the gun shop is a fellow gear head so it's pretty tough to get people to complain around here.
Hoss7979
1/2 ton status
Well w/ 4.56 & 37's your right on the boarder of good mpg & back to stock gearing. So with a BBC your only gonna get more HP/TQ which ya can't beat that! I would throw a Comp Cam extreme 4x4 cam in it & depending on your head casting numbers you could have a nice BBC going. I run a 468 w/ big heads & big cam. I will never go back to a SBC again. With the burban tank in there thatll be a plus. My setup is 468, TH350/NP205, 60/14 w/ 5.13's & 39.5 TSL's. There's some other tips & tricks to BBC's that'll help ya as well. Let me know if ya needs some help or have any questions on builds. I did all my own work to mine when I was in college, bored, honed, line honed, lifter valley work & clean up.
Well, I started honing a little while ago. Started on the right side, cylinder 2 and 4 look great, then got to 6 and there's some pitting in the cylinder wall. I guess if I want to get serious about building this thing I need to start looking into machine shops.
I have the 781 heads that I planned to have reworked for the larger valves. It's just hard for me to dump a lot of money into this engine when I could get a 6.0 that'd be more reliable and already fuel injected for probably the same price.
I have the 781 heads that I planned to have reworked for the larger valves. It's just hard for me to dump a lot of money into this engine when I could get a 6.0 that'd be more reliable and already fuel injected for probably the same price.
Figured I'd finish honing this thing to see what every cylinder looks like. The pit in number 6 is in between where the top and bottom piston rings would be on the very top of the stroke. Number 8 looks good, there's a visible scratch in it, but I can't catch it with my fingernail when I run it across it. Then my drill battery died on me when I moved to cylinder 1.
Hoss7979
1/2 ton status
If you want 1/2 the HP/TQ then go w/ the 6.0! People get all hot & bothered by them but when you look @ the horsepower & torque output.......they are way up in the rpm band. There output is also what a BBC makes @ or around idle!!!!
I only plan on honing out the surface rust and get some hash marks. I'm going to call the machine shop Tuesday to get a quote on doing my heads, I'll see what they want to bore it out and if it's not too bad I'll let them do it. I don't have a way to measure bore taper or roundness... 
I already plan on getting some little dome Pistons for it anyway, "might as well..."
I already plan on getting some little dome Pistons for it anyway, "might as well..."
put a ring in it, square it in up in the bore with an inverted piston about 3/4" down measure the gap with feeler guage, then push the ring down to the bottom of the stroke (about 4.25") from the deck, square it in the cylinder and measure again...the difference is roughly the taper. IIRC a 454 is less than .003 for taper...also check the very top of the cylinder to measure the gap where the rings haven't worn the wall yet...roundness can be checked with a ring and shining a flashlight against the bore from underside to see if there is any small gaps between the wall and the ring. If there is, rotate the ring 90* and try again. Should be no light shining through between the ring and wall.
Oh and those 781's love a 2.19/1.88 treatment with a good sized cam.....here is what I got in mine: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=468&sb=2
Not once have I said, gee I wish I wouldn't have put a Big block in my truck!
Oh and those 781's love a 2.19/1.88 treatment with a good sized cam.....here is what I got in mine: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=468&sb=2
Not once have I said, gee I wish I wouldn't have put a Big block in my truck!
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Hoss7979
1/2 ton status
Bigger valves want more fuel if you stick w/ the 2.06/1.72 you gonna have better fuel economy. Your also gonna want a domed piston to get compression up to 9.5-10 w/ the 781 heads. Make sure they measure the chambers for ya, they can range from 113-118cc's. This is the cam I run right now in mine.....http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=401&sb=2. Fairly mild but does well in a heavy vehicle. This next winter it's very more compression added & a .595/.595 mechanical flat tappet.
Hmmm, valve lash
Not an issue
I think that's blown out of proportion
I've run my Vette usually up to the 6800 redline at least 500 drag runs plus a few thousand miles street driving and it's never been more than .001 from the spec lash. That is one the reason I didn't shy away from the mech lifters for the BBC in the Maiden, the other reason came from my head/valvetrain guy. I've checked this engine twice and the 5500 limit I've put on it shows me it isn't worth worrying about.
I do use a flat tappet additive in all my flat tappet engines too.
I think that's blown out of proportion
I've run my Vette usually up to the 6800 redline at least 500 drag runs plus a few thousand miles street driving and it's never been more than .001 from the spec lash. That is one the reason I didn't shy away from the mech lifters for the BBC in the Maiden, the other reason came from my head/valvetrain guy. I've checked this engine twice and the 5500 limit I've put on it shows me it isn't worth worrying about.
I do use a flat tappet additive in all my flat tappet engines too.
Actually, I'm a fan. Something about a little rocker clatter that makes me happy. Might have something to do with years of drag racing
Take it a fat bottom girl never took advantage of youThings escalating quickly, eh?
