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I was very lucky where I took my motor to have all the block machine work done. One guy there does head porting work on the side with a flow bench. He does lots of LS stuff. The guy said that the out of the box heads are usually in need of attention and bare heads are the best option. I am so glad I started buying stuff years ago for this project.
 

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Discussion Starter · #42 ·
I have put everybody's data in a spreadsheet, but had to convert it to a pdf to upload to the thread. It is attached to the first post of this thread. I will update it as more builds are posted. If you want the Excel spreadsheet, PM me with your email address.
 

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Discussion Starter · #43 ·
I have been doing some research to go along with my dreaming of the stroker engine build. I have estimated that I can buy a stroker engine kit that ranges from a 463 to a 490 cubic inches for $2400 to $3400. These cubic inches were generated by using their custom piston options, and an assumed 40-over bore. I used Butler's site to come to these conclusions since it's pretty easy to select the options and build a total price. I pretty much went with the middle of the road upgrades for options and found that the extra money you need to spend to get from the 463 to the 490 is about a thousand dollars...$37 per cubic inch. I am thinking that a 9 to 9.5:1 compression ratio should be my goal.

Here's a couple question for those of you who have built one of these engines...

Given I have the extra thousand, why would I not build the larger 490 cu-in stroker engine?

I intend to use the stock 4bbl intake, HO exhaust mani's, 670 heads - all port matched - and a Ram Air-like cam...if that makes a difference.
 

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Nice work, thanks ! It shows the ignition for mine is the Blaster but I have the MSD R2R..no biggie. What is your main use for the car, are you shooting for a certain HP, or TQ number, do you have the drive line to support,??? Idk but you can build a pretty potent 461 and put the extra 1k into something else imo. Is 490 going to be that much more powerful than 461,463,467 idk?
 

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Discussion Starter · #45 ·
Baaad65 , I corrected the spreadsheet...thanks for the proof read. I wonder where the Blaster even came from? I have updated the file on the original post. Somebody else's data is probably wrong...hmmm?

My build is pretty much an open book. My goals are...

91-93 octane.
Street-able.
To stay around 1 horse power per cubic inch.
Rear Gear Ratio around the mid to low 3's, Maybe a 12 bolt for the strength.
Get traction, not smoke, so drag radials are a possibility, no tubbing.
Keep a very stock look to the engine (and car).

I will drive this car on sunny days to work and want to do it "fast"...lol
 

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1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used (ie 400, 455, etc) - Cast Eagle 4.250 stroke, 3.00 mains
3 Stroker Kit Used (ie 461, 467, 471, etc) - 467
4 Final Bore Diameter - 4.181"
5 Final Deck Height - ???
6 Piston (Type, Make & Model) - Ross/Butler 4.181 x 1.295 CH (6.800 x 4.250 stroke) Flat Top Forged
7 Compression Ratio (Static) - 10.3
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) - Pontiac Iron 6X-4 with mild porting and multi angle valve work done locally
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.66" exhaust
11 Head Chamber Size (Actual in cc's) - 93.74
12 Head gasket thickness - .040
13 Intake to Head Port Matched? - No
14 Head to Exhaust Port Matched? - No
15 Intake (Make & Model) - Edelbrock P65 dual plane dual four barrel carburetors
16 Exhaust Manifolds or Headers - RARE oversized ram air reproductions
17 Exhaust Manifolds or Headers (Make & Model) - 64-67 2.5" outlet RA Manifolds, ceramic coated
18 Carburetor (Make & Model) - Edelbrock 1405 and 1406 600CFM carburetors with 1:1 linkage
19 Cam (Make & Model) - Butler/Comp Cams Extreme Energy XE 274 HFT
20 Cam Specs - 274/286, 230/236, .488/.491, 110 (If I ever change, I may try the 068 grind)
21 Rocker Ratio - 1.52
22 Rocker Type (Stamped or Roller) - Stamped with roller tip
23 Rocker (Make & Model) - Comp Cams Magnum Roller tip
24 Push Rod Length - 9.130
25 Estimated Flywheel Horse Power - ???
26 Dyno'd Flywheel Horse Power - ???
27 Dyno'd Horse Power at the rear tires - I have no idea but my 400s never had near this much torque!
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd Flat Tappet
29 Lifter (Make & Model) - Comp Cams standard Pontiac
30 Ignition: - Pertronix Flame Thrower, MSD 6AL with rev limiter and remote timing control
31 Fuel Octane - 95 to 100? Depends if I want to run with timing set at 16 or 18. 18 runs better and cooler.
32 How do you get to that octane (91, 93, + additive w/brand, race fuel mix, etc) -93 plus Octane Supreme. I may be changing to VP Octanium for a variety of reasons (cost, availability, toxicity).
 

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I have been doing some research to go along with my dreaming of the stroker engine build. I have estimated that I can buy a stroker engine kit that ranges from a 463 to a 490 cubic inches for $2400 to $3400. These cubic inches were generated by using their custom piston options, and an assumed 40-over bore. I used Butler's site to come to these conclusions since it's pretty easy to select the options and build a total price. I pretty much went with the middle of the road upgrades for options and found that the extra money you need to spend to get from the 463 to the 490 is about a thousand dollars...$37 per cubic inch. I am thinking that a 9 to 9.5:1 compression ratio should be my goal.

Here's a couple question for those of you who have built one of these engines...

Given I have the extra thousand, why would I not build the larger 490 cu-in stroker engine?

I intend to use the stock 4bbl intake, HO exhaust mani's, 670 heads - all port matched - and a Ram Air-like cam...if that makes a difference.
Sorry late to the party here. I'm thinking one thing you would want to find out is if you would need to clearance the block to go with a 490 ci build. With what your intended use is, you may just be making a car that's already going to be bad on gas even worse. A 461/467 build is going to be blisteringly fast in a street car.
 

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Discussion Starter · #49 ·
Michael, I'll get your stats put in the spreadsheet when I get my laptop replaced in about a month. I refused to work that hard on my 17 year old desktop...it's tooooo slow. Thanks for posting your info!

Sorry late to the party here. I'm thinking one thing you would want to find out is if you would need to clearance the block to go with a 490 ci build. With what your intended use is, you may just be making a car that's already going to be bad on gas even worse. A 461/467 build is going to be blisteringly fast in a street car.
I have 670 heads and intend to use them to keep the casting numbers and to save from spending more money. What research I have done tells me that the 461/467 stroker kits using the 670 heads tend to have the CR upwards around 10:1 or more, while I have seen a 490 kit that drops it down to the 9's with the 670 heads. My somewhat inexperienced theory is that I could go with more cubes to get the power back from dropping the CR. I think I will end up with more power with the 490 kit & a lower compression ratio, when compared to the lesser cubes, but higher CR...but not by a whole lot. This keeps me from having to drive to the airport for fuel or buying & mixing octane booster.

With the 490 kit idea, I am still concerned about what restrictions I would observe by using the original intake and 3" HO exhaust manifolds (both poor-man port matched). 490 cubes may want more air flow, but that lack of air flow may even act as insurance that the engine will not wrap up too quick and "pop". I'm OK with throttling the engine this way so long as it can be tuned to run well with these parts. Once again, a strong stock appearance is part of my intentions along with the budget savings.

I will have to call Butler and talk about clearance needs, but I'm ok with some clearance mods.

I'm not too concerned with gas mileage and "blistering fast" is part of my goals.
 

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Michael, I'll get your stats put in the spreadsheet when I get my laptop replaced in about a month. I refused to work that hard on my 17 year old desktop...it's tooooo slow. Thanks for posting your info!



I have 670 heads and intend to use them to keep the casting numbers and to save from spending more money. What research I have done tells me that the 461/467 stroker kits using the 670 heads tend to have the CR upwards around 10:1 or more, while I have seen a 490 kit that drops it down to the 9's with the 670 heads. My somewhat inexperienced theory is that I could go with more cubes to get the power back from dropping the CR. I think I will end up with more power with the 490 kit & a lower compression ratio, when compared to the lesser cubes, but higher CR...but not by a whole lot. This keeps me from having to drive to the airport for fuel or buying & mixing octane booster.

With the 490 kit idea, I am still concerned about what restrictions I would observe by using the original intake and 3" HO exhaust manifolds (both poor-man port matched). 490 cubes may want more air flow, but that lack of air flow may even act as insurance that the engine will not wrap up too quick and "pop". I'm OK with throttling the engine this way so long as it can be tuned to run well with these parts. Once again, a strong stock appearance is part of my intentions along with the budget savings.

I will have to call Butler and talk about clearance needs, but I'm ok with some clearance mods.

I'm not too concerned with gas mileage and "blistering fast" is part of my goals.
I think you have this backwards. The larger cube engine will push the compression ratio even higher.

 

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hey bear, do you like the 850 with annular boosters? i have a holley 850 dp with annular boosters but haven't used it yet.
Dang... I'm just now seeing this? My bad!!

I like it ok - now. It gave me fits when I first got it and I had to modify nearly every circuit on it to get it running halfway right. But that was "before" my most current build - and that one had a problem I didn't discover for a long time (hence the reason I went through it again to arrive at my current build). I ended up having to UNDO all the modifications I'd made to the carb to make it run right now, which it does just fine. Go figure.

And, since I've added that new ignition system from Progression Ignition, the car is MUCH nicer to drive. The cam I have, I really like, but it has this one unpleasant characteristic: at idle, even a tiny difference in RPM has a monster effect on manifold vacuum. When vacuum drops, so does the signal to the idle circuit and the carb goes lean, which drops RPM more.... and the car wanted to die all the time. Even the slight RPM drop caused by my electric fans kicking in was enough to start it happening.

This fancy ignition system senses when vacuum drops off and idle RPM starts to go with it, and adds in some advance to compensate. It's really nice. I can actually brake to a stop and sit now without having to dance on the gas pedal to keep it running. :D

Bear
 

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Dang... I'm just now seeing this? My bad!!

I like it ok - now. It gave me fits when I first got it and I had to modify nearly every circuit on it to get it running halfway right. But that was "before" my most current build - and that one had a problem I didn't discover for a long time (hence the reason I went through it again to arrive at my current build). I ended up having to UNDO all the modifications I'd made to the carb to make it run right now, which it does just fine. Go figure.

And, since I've added that new ignition system from Progression Ignition, the car is MUCH nicer to drive. The cam I have, I really like, but it has this one unpleasant characteristic: at idle, even a tiny difference in RPM has a monster effect on manifold vacuum. When vacuum drops, so does the signal to the idle circuit and the carb goes lean, which drops RPM more.... and the car wanted to die all the time. Even the slight RPM drop caused by my electric fans kicking in was enough to start it happening.

This fancy ignition system senses when vacuum drops off and idle RPM starts to go with it, and adds in some advance to compensate. It's really nice. I can actually brake to a stop and sit now without having to dance on the gas pedal to keep it running. :D

Bear
thank you, i figured you were busy. my 850 has 78 primary and 82 secondary jets 6.5 power valve. im running a 041 cam in a 400 10.38 compression. do you think that works together good? or is that a try it and see what happens. im still thinking of building my q jet. the more i look at it and understand all the adjustments it has the more i like it.
 

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thank you, i figured you were busy. my 850 has 78 primary and 82 secondary jets 6.5 power valve. im running a 041 cam in a 400 10.38 compression. do you think that works together good? or is that a try it and see what happens. im still thinking of building my q jet. the more i look at it and understand all the adjustments it has the more i like it.
I have 78 and 84's in my 850 Quickfuel with a 7.5 high flow PV and #35 nozzle squirters, blue cams on the #2 hole I believe, 1/2" phelonic spacer...runs great, plugs look good but I have a different dizzy curve than most. Just my 2 cents 😉
 

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I have 78 and 84's in my 850 Quickfuel with a 7.5 high flow PV and #35 nozzle squirters, blue cams on the #2 hole I believe, 1/2" phelonic spacer...runs great, plugs look good but I have a different dizzy curve than most. Just my 2 cents 😉
thank you, i suspect i will have to tinker with it. but hope its close. i might be pushing 400 -425 hp. but i don't have a dyno. im still gathering parts. got some dss forged pistons the other day. very nice quality. one piece at a time.as the song goes.
 

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thank you, i figured you were busy. my 850 has 78 primary and 82 secondary jets 6.5 power valve. im running a 041 cam in a 400 10.38 compression. do you think that works together good? or is that a try it and see what happens. im still thinking of building my q jet. the more i look at it and understand all the adjustments it has the more i like it.
One thing I do highly HIGHLY (did I mention highly) recommend is getting and using a good, wide band air/fuel gauge to tune it. "Old guys" used to do that by reading spark plugs, but that's a skill I don't have and todays fuel additives make that a lot more difficult to do correctly anyway.

I've got one in my car full time now in the same gauge panel as I have a digital oil pressure gauge, coolant temp gauge, and transmission temp gauge, but before that I used one of the portable Innovate LM2 meters. Having a gauge made it a lot easier to get the fuel mixtures dialed in for all modes of operation from idle to WOT.

Remember I've got a reasonably rowdy solid roller cam so that affects things , but right now, I'm running 81's in the primaries, 91's in the secondaries, 0.070 idle bleeds, 0.031 high speed bleeds, 0.035 idle feed restrictors, a 4.5 power valve, 0.063 power valve channel restrictors, 0.035 pump nozzles on both ends, 50 cc pumps also on both ends with the 'yellow' pump cam, float levels set to halfway up the glass on both ends.
My idle is at high 13's low 14's, off-idle light throttle cruise runs in the mid to upper 12's, high cruise around 12.5, and WOT is 12.3-12.5.
One thing I discovered working on it is that most of the time, up until about 50-60mph, the thing is running mostly on the transfer slots and not even getting into mains much at all.

Before I got that fancy ignition system, braking to a stop and/or seeing the fans kick on would cause idle to to way lean as RPM dropped, up into the 15's 16's or even higher and it was hard to keep it running even if I set the idle up around 1100 or so. That doesn't happen now and I can hold a 900 RPM idle even in gear, with the fans on.

Bear
 

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One thing I do highly HIGHLY (did I mention highly) recommend is getting and using a good, wide band air/fuel gauge to tune it. "Old guys" used to do that by reading spark plugs, but that's a skill I don't have and todays fuel additives make that a lot more difficult to do correctly anyway.

I've got one in my car full time now in the same gauge panel as I have a digital oil pressure gauge, coolant temp gauge, and transmission temp gauge, but before that I used one of the portable Innovate LM2 meters. Having a gauge made it a lot easier to get the fuel mixtures dialed in for all modes of operation from idle to WOT.

Remember I've got a reasonably rowdy solid roller cam so that affects things , but right now, I'm running 81's in the primaries, 91's in the secondaries, 0.070 idle bleeds, 0.031 high speed bleeds, 0.035 idle feed restrictors, a 4.5 power valve, 0.063 power valve channel restrictors, 0.035 pump nozzles on both ends, 50 cc pumps also on both ends with the 'yellow' pump cam, float levels set to halfway up the glass on both ends.
My idle is at high 13's low 14's, off-idle light throttle cruise runs in the mid to upper 12's, high cruise around 12.5, and WOT is 12.3-12.5.
One thing I discovered working on it is that most of the time, up until about 50-60mph, the thing is running mostly on the transfer slots and not even getting into mains much at all.

Before I got that fancy ignition system, braking to a stop and/or seeing the fans kick on would cause idle to to way lean as RPM dropped, up into the 15's 16's or even higher and it was hard to keep it running even if I set the idle up around 1100 or so. That doesn't happen now and I can hold a 900 RPM idle even in gear, with the fans on.

Bear
do those gauges need to go in both exhaust? one gauge for each?
 

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do those gauges need to go in both exhaust? one gauge for each?
I just have one on one side. I do have two bungs, one welded on each side, though --- only because I had an LM2 at first and then went to a full time mounted gauge. The one I used with the LM2 is on the passenger side because it was easier to snake the wiring in and out of the car from that side. For the permanent installation, putting the O2 sensor on the driver side ended up being "cleaner".
I can still hook up the LM2 if I ever want to get readings from both banks, but so far I haven't felt the need to.
 
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