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Discussion Starter · #1 · (Edited)
I though it would be a good thing to start a thread where owners of stroked Pontiac engines could share their builds. I will be picking out the parts to build a stroked 400 block and would love to look through a list of builds to give me an idea of what others have successfully done.

Below is a list of engine specs that largely describe an engine build...or at least enough to make decent comparisons. If you have other specs that should be added to the list...let me know and I will add it to the list right below as we go.

If your build is not top secret, share the specs of your stroker build (as much as you know, anyhow). Feel free to link other stroker build threads or spec lists that you know of...If we get enough builds, I will compile the data in a spread sheet for easy comparisons.

Stroker Specs

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used (ie 400, 455, etc) - ???
3 Stroker Kit Used (ie 461, 467, 471, etc) - ???
4 Final Bore Diameter - 4.150"
5 Final Deck Height - ???
6 Piston (Type, Make & Model) - ???
7 Compression Ratio (Static) - ???
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) - 670 OEM
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" exhaust
11 Head Chamber Size (Actual in cc's) - 72
12 Head gasket thickness -
???
13 Intake to Head Port Matched? - Yes
14 Head to Exhaust Port Matched? - Yes
15 Intake (Make & Model) - '67 OEM 400
16 Exhaust Manifolds or Headers - Manifolds
17 Exhaust Manifolds or Headers (Make & Model) - 2.5" RA Manifolds
18 Carburetor (Make & Model) - Quadra Jet OEM
19 Cam (Make & Model) - ???
20 Cam Specs - ???
21 Rocker Ratio - ???
22 Rocker Type (Stamped or Roller) -
Stamped
23 Rocker (Make & Model) -
OEM
24 Push Rod Length - ???
25 Estimated Flywheel Horse Power - ???
26 Dyno'd Flywheel Horse Power - ???
27 Dyno'd Horse Power at the rear tires - ???
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd Tappet

29 Lifter (Make & Model) - ???
30 Ignition: - OEM Points
31 Fuel Octane - ???
32 How do you get to that octane (91, 93, + additive w/brand, race fuel mix, etc) - ???


The above list can be copied from this post and pasted into your post for filling the specs. The above is all I know of my build so far and I will fill it in as it becomes more compete or change my mind, as I will!

I have attached a spreadsheet with everybody's data up to July 15th, 2022. If you want the Excel spreadsheet, PM me with your email address.
 

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Discussion Starter · #3 ·
I have read and appreciated so much of Bear's lendings to the forum (and many others, that's why I'm here). I can tell he holds a large amount of knowledge. I am sure he will have an influence on my build, if he hasn't already. (y) This is the reason for the thread...It's an invite to share you build to help all, myself included, to get started on a stroker build.

I'm looking at starting with the rear tires as the key design factor. I'm not tubbing my car so, the largest tire that seems common is the 8 wide rim. Maybe I can get a 9" with the right rim and rear end sett-up...10" ??? I will certainly consider running drag radials (or cheater slicks). I want to build the rest of the drive line to accommodate that type of tire traction. I'm not entering a burn-out competition...I want to hook up and run quarters well, while looking rather original, but not sounding it.
 

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Nice idea... here's mine:

Stroker Specs

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used (ie 400, 455, etc) - Forged Eagle - 4.250 stroke - 3.000 mains
3 Stroker Kit Used (ie 461, 467, 471, etc) - Forged Eagle H-Beam rods - 6.800 length, King Racing main and rod bearings, Total Seal file fit rings, gapless top, LUHN 80 psi oil pump
4 Final Bore Diameter - 4.160"
5 Final Deck Height - Original to the car block (hasn't been decked)
6 Piston (Type, Make & Model) - Forged, Ross Custom, D-shaped dishes with 14cc's clearance volume
7 Compression Ratio (Static) - 10.49:1
8 Compression Ratio (Dynamic) - 8.2-8.3:1 (depending on whose calculator I use)
9 Heads (Make & Model) - Edelbrock RPM round port, Dave Wilcox "entry level " ported
10 Head Valve Size (Intake & Exhaust) - 2.190" intake, 1.77" exhaust
11 Head Chamber Size (Actual in cc's) - 74
12 Head gasket thickness - 0.042
13 Intake to Head Port Matched? - Yes
14 Head to Exhaust Port Matched? - No
15 Intake (Make & Model) - KRE Northwind
16 Exhaust Manifolds or Headers - Headers
17 Exhaust Manifolds or Headers (Make & Model) - Doug's, D567 - JetHot ceramic coated
18 Carburetor (Make & Model) - AED 850-HO w/annular boosters
19 Cam (Make & Model) - Bullet
20 Cam Specs - 251/257 I./E. duration @ 0.050 tappet lift, 110 LSA, 0.620 net lift at the valves (lash accounted for, with 1.5's), installed @ 106 ICL
21 Rocker Ratio - 1.5:1
22 Rocker Type (Stamped or Roller) - Full Roller
23 Rocker (Make & Model) - Crower Enduro Stainless - 1.5:1 ratio
24 Push Rod Length - 9.300 Smith Bros. - 5/16 0.116 wall
25 Estimated Flywheel Horse Power - 560 "or so"
26 Dyno'd Flywheel Horse Power - Haven't
27 Dyno'd Horse Power at the rear tires - Haven't
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Solid Roller

29 Lifter (Make & Model) - Crower Cutaway Standard Height w/High Pressure Pin Oiling option
30 Ignition: Progression Ignition computerized HEI

Bear
 

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I have read and appreciated so much of Bear's lendings to the forum (and many others, that's why I'm here). I can tell he holds a large amount of knowledge. I am sure he will have an influence on my build, if he hasn't already. (y) This is the reason for the thread...It's an invite to share you build to help all, myself included, to get started on a stroker build.

I'm looking at starting with the rear tires as the key design factor. I'm not tubbing my car so, the largest tire that seems common is the 8 wide rim. Maybe I can get a 9" with the right rim and rear end sett-up...10" ??? I will certainly consider running drag radials (or cheater slicks). I want to build the rest of the drive line to accommodate that type of tire traction. I'm not entering a burn-out competition...I want to hook up and run quarters well, while looking rather original, but not sounding it.
Same 👍
 

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So here's mine that was built by Butler in 2014 for a guy that sold it to the guy I got it from with neither of them installing it, but I did into my '65 in 2018. I kept watching for the cops on the way home because I felt like a thief, it's cut off of the picture but the build sheet shows 12,600.00....I paid 7500.00 ! So I changed out the intake to an Eddy Performer RPM, changed out the carb to an 850 dp custom Quickfuel, and changed out the rockers to Scorpion 1.65 Race, also 2.5" ram air exhaust manifolds. From my research it's about 9.36 : 1 compression. I always use 93 octane with 36° total advance with no detonation, it's a 4spd with a 2.99 first gear and a 3.42 twelve bolt with lift bars and 275/60/15 drag radials and I still can't get good traction, I think it's got to be close to 500hp...in other words a beast that puts an ear to ear smile on me every time I pound the go pedal 😊
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I have read and appreciated so much of Bear's lendings to the forum (and many others, that's why I'm here). I can tell he holds a large amount of knowledge. I am sure he will have an influence on my build, if he hasn't already. (y) This is the reason for the thread...It's an invite to share you build to help all, myself included, to get started on a stroker build.

I'm looking at starting with the rear tires as the key design factor. I'm not tubbing my car so, the largest tire that seems common is the 8 wide rim. Maybe I can get a 9" with the right rim and rear end sett-up...10" ??? I will certainly consider running drag radials (or cheater slicks). I want to build the rest of the drive line to accommodate that type of tire traction. I'm not entering a burn-out competition...I want to hook up and run quarters well, while looking rather original, but not sounding it.
FYI, Your safest bet on rear rim/tire width will be an 8" rim if you want to keep it inside the well. We had a member with a 1969 GTO ad 12-bolt. Here is what he had that fit inside his wheel wells with some lip rolling:

"I run M/T streets 29.5x12.5 on a 9.5" wide Weld rim with 5.5 backspace. Stock wheelwells, stock rear end width. Honestly the biggest set of tires I could fit in the stock wheelwells although I did do some trimming and I also rolled the fender lips to prevent cutting the sidewalls. To fit your rims you will have to jack up the rear. I would consider trying to get a wheel that will fit in the wheel wells. Go to my "garage" and I think there are some other pictures of my car that show how well it fits. Both my rims were custom ordered it is very difficult to find a wheel with this off set. John. "

And here is another post I saved:

"If you want a 28" tire:
You can run Mickey Thompson 28x11.5-15 ET Streets
You can run Mickey Thompson 275/60r-15 ET Street Radials

If you're really making power, and want a 30" tire:

You can run Mickey Thompson 30x12.5-15 ET Streets
You can run Mickey Thompson 295/65r-15 ET Street Radials
You can run Mickey Thompson 315/60r-15 ET Street Radials

I have 295, and 315 radials on a 8" rim.

On an A-body, it’s hard to beat a 275/60/15 on the rear and a 225/70/15 on the front. Fills the wheel wells without the “joe dirt” look....

I’ve run just about every tire made. The 275/60/15 Mickey drag radials get the job done. Running the “pro” version as we speak, EXCELLENT tire!"

I will be running the Hoosier 30x12.5-15 tires on a 10" aluminum slot rim having a 3.5" backspacing, but the car will be jacked up in the back to clear the tires, and if I have to do any trimming for clearance, I don't have an issue cutting the wheel wells a little for fit and finish - but I don't believe I will have to.

Tire Wheel Automotive tire Tread Synthetic rubber
Wheel Automotive tire Alloy wheel Rim Tire
 

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Here's mine. Some of my choices were not conventional but it is extremely healthy at everything except very low RPMs.

I started with a short block so I don't have 100% of the information on it but here's a link: 455 Short Block

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400 - 1971 block
2 Crank Size Used (ie 400, 455, etc) - Eagle 4.250 stroke
3 Stroker Kit Used (ie 461, 467, 471, etc) -461
4 Final Bore Diameter - 0.030" overbore
5 Final Deck Height - ???
6 Piston (Type, Make & Model) - ???
7 Compression Ratio (Static) -9.5 : 1
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) -6X ported with larger exhaust valves (Nitemare Performance Stage II)
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" exhaust
11 Head Chamber Size (Actual in cc's) - 96 cc
12 Head gasket thickness -0.045"
13 Intake to Head Port Matched? - Yes
14 Head to Exhaust Port Matched? -no
15 Intake (Make & Model) -Torquer II
16 Exhaust Manifolds or Headers -Shorty Headers
17 Exhaust Manifolds or Headers (Make & Model) -Heddman
18 Carburetor (Make & Model) -Edelbrock Performer 800 CFM
19 Cam (Make & Model) - Comp Cams Extreme Energy XE284H CCA-51-225-4
20 Cam Specs -lift 0.507"/0.510" duration 284/296intake/exhaust 110 deg of lobe separation
21 Rocker Ratio -1.5
22 Rocker Type (Stamped or Roller) -Roller,
23 Rocker (Make & Model) -Comp Ultra Gold
24 Push Rod Length - 9.450" Smith Bros
25 Estimated Flywheel Horse Power - ~500 estimated by Darrin at Nitemare
26 Dyno'd Flywheel Horse Power -NA
27 Dyno'd Horse Power at the rear tires -NA
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd flat Tappet
29 Lifter (Make & Model) - Comp
30 Ignition: - Pertronex HEI with vac advance

added:

31 Fuel Octane - 93
32 How do you get to that octane (91, 93, + additive w/brand, race fuel mix, etc) - at the gas pump 93 is available in MA
 

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Here's mine. Some of my choices were not conventional but it is extremely healthy at everything except very low RPMs.

I started with a short block so I don't have 100% of the information on it but here's a link: 455 Short Block

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used (ie 400, 455, etc) - ???
3 Stroker Kit Used (ie 461, 467, 471, etc) -461
4 Final Bore Diameter - 4.250"
5 Final Deck Height - ???
6 Piston (Type, Make & Model) - ???
7 Compression Ratio (Static) -9.5 : 1
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) -6X ported with larger exhaust valves (Nitemare Performance Stage II)
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" exhaust
11 Head Chamber Size (Actual in cc's) - 96 cc
12 Head gasket thickness -0.045"
13 Intake to Head Port Matched? - Yes
14 Head to Exhaust Port Matched? -no
15 Intake (Make & Model) -Torquer II
16 Exhaust Manifolds or Headers -Shorty Headers
17 Exhaust Manifolds or Headers (Make & Model) -Heddman
18 Carburetor (Make & Model) -Edelbrock Performer 800 CFM
19 Cam (Make & Model) - Comp Cams Extreme Energy XE284H CCA-51-225-4
20 Cam Specs -lift 0.507"/0.510" duration 284/296intake/exhaust 110 deg of lobe separation
21 Rocker Ratio -1.5
22 Rocker Type (Stamped or Roller) -Roller,
23 Rocker (Make & Model) -Comp Ultra Gold
24 Push Rod Length -don't remember
25 Estimated Flywheel Horse Power - ~500 estimated by Darrin at Nitemare
26 Dyno'd Flywheel Horse Power -NA
27 Dyno'd Horse Power at the rear tires -NA
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd flat Tappet
29 Lifter (Make & Model) - Comp
30 Ignition: - Pertronex HEI with vac advance
jared, i think you mean 4.25 stroke probably a .060 over 400 bore. sounds like a nice combo.
 

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Here's mine. Some of my choices were not conventional but it is extremely healthy at everything except very low RPMs.

I started with a short block so I don't have 100% of the information on it but here's a link: 455 Short Block

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used (ie 400, 455, etc) - ???
3 Stroker Kit Used (ie 461, 467, 471, etc) -461
4 Final Bore Diameter - 4.250"
5 Final Deck Height - ???
6 Piston (Type, Make & Model) - ???
7 Compression Ratio (Static) -9.5 : 1
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) -6X ported with larger exhaust valves (Nitemare Performance Stage II)
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" exhaust
11 Head Chamber Size (Actual in cc's) - 96 cc
12 Head gasket thickness -0.045"
13 Intake to Head Port Matched? - Yes
14 Head to Exhaust Port Matched? -no
15 Intake (Make & Model) -Torquer II
16 Exhaust Manifolds or Headers -Shorty Headers
17 Exhaust Manifolds or Headers (Make & Model) -Heddman
18 Carburetor (Make & Model) -Edelbrock Performer 800 CFM
19 Cam (Make & Model) - Comp Cams Extreme Energy XE284H CCA-51-225-4
20 Cam Specs -lift 0.507"/0.510" duration 284/296intake/exhaust 110 deg of lobe separation
21 Rocker Ratio -1.5
22 Rocker Type (Stamped or Roller) -Roller,
23 Rocker (Make & Model) -Comp Ultra Gold
24 Push Rod Length -don't remember
25 Estimated Flywheel Horse Power - ~500 estimated by Darrin at Nitemare
26 Dyno'd Flywheel Horse Power -NA
27 Dyno'd Horse Power at the rear tires -NA
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd flat Tappet
29 Lifter (Make & Model) - Comp
30 Ignition: - Pertronex HEI with vac advance
So I see you have 9.5 compression, are they flat top pistons because going by the chart on Butler's site mines coming in at 9.36 but I have smaller head chambers at 92cc than yours. Idk the gasket thickness but could look it up and don't know how much the piston is in the hole, mine is 0.35 or 0.40 over with a 455 crank. Maybe I have more compression than I think.
 

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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.
Man is that ever a loaded question... :censored: To be honest, I'm not sure that I've ever gotten it really "right" on my current build. 'Tis a long and sad tale that I won't bore everyone with excessively (I hope),so I'll try to summarize. When I first built the engine after the 2016 rocker failure and "upgraded" to the current configuration, I had the devil of a time trying to get the carb dialed in and ended up reworking/recalibrating nearly every circuit in it in the attempt. Turns out, there was a mechanical issue in one cylinder that was throwing everything out of whack that ended up causing yet another tear down and rebuild. It's only been back together from that build for about 7 months now, and so far I've had to "undo" nearly every change I made to the carb prior to that. I thought I finally had it, but the last time I drove it just a couple weekends ago in our currently and consistently 100+ degree heat here, it started acting up again and running SUPER rich at idle/low throttle in the heat. And I'm not sure why yet. It was so ugly I wasn't sure I was going to get it back home.

Part of the challenge I'm sure is caused by the cam I'm running. from about 1000 rpm down to 800 rpm, the vacuum signal drops off a cliff which I'm thinking is playing havoc with the idle circuit. When RPM drops, the thing goes extremely lean and doesn't want to keep running. Just a slight increase in engine load at idle, like when the electric cooling fans kick in and put load on the alternator, is enough to make it really unhappy.

The more I think about it, the more I'm inclined to reset it back to "out of the box" configuration and start over, solely on the assumption that the guys at AED probably had it close to right as it was shipped and I just didn't know it because of the other problems I had.

The nice thing about Holley's is that they're super adjustable. The worst thing about Holley's is that they're super adjustable (lots of opportunities to get things wrong).

Bear
 

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So I see you have 9.5 compression, are they flat top pistons because going by the chart on Butler's site mines coming in at 9.36 but I have smaller head chambers at 92cc than yours. Idk the gasket thickness but could look it up and don't know how much the piston is in the hole, mine is 0.35 or 0.40 over with a 455 crank. Maybe I have more compression than I think.
Yep. They are flat top. I was also going by what I remembered calculating two years ago when I set all this up. It's possible I neglected to include the gasket thickness into the equation at the time. I also found slight variations from one calculator to the next for different Pontiac websites. Could be mine is closer to 9 to 1 or yours is a little higher than you think. Either way, it probably doesn't make a huge difference.
 

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jared, i think you mean 4.25 stroke probably a .060 over 400 bore. sounds like a nice combo.
Ha! I'll fix that. It was supposed to be a 0.030" overbore on an uncut 400 block. I copied the OPs list and changed what didn't match mine. Saw the 4.25 and went with it.

I have edited a few things above. Added the push rod length and adjusted a few of the other things too. Since I didn't build the bottom end, I was going on what I remembered from conversation with Len from over 2 years ago. The paperwork is somewhere but my organization skills on that sort of thing is a bit spotty. I'm not a binder full of receipts type of guy. Honestly, with what this cost to put together, probably a good thing I didn't keep close records.
 

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Here's the chart from Butler for popular builds, since I don't know all the specs of mine I went by this. So 9.36 is with 96cc chambers and mine are 92cc so maybe I'm at 9.4:1 ?
Now that I see it I remember using that as a guide early in my build planning stage. I was originally planning on going with 87cc aluminum heads and a roller cam. Then I started running costs and it started to get out of hand. I ran across Nitemare (Darrin) and found their prices for the ported cast to be very fair. He was the one who talked me into a flat tappet camshaft. Even with reducing the cost on the heads and cam, my build went way over budget (hence the not being to meticulous with receipts). Luck had it that I ordered everything I needed for the build and then waited for the block and heads. Prices went way up by the time I put all of this together.
 

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Now that I see it I remember using that as a guide early in my build planning stage. I was originally planning on going with 87cc aluminum heads and a roller cam. Then I started running costs and it started to get out of hand. I ran across Nitemare (Darrin) and found their prices for the ported cast to be very fair. He was the one who talked me into a flat tappet camshaft. Even with reducing the cost on the heads and cam, my build went way over budget (hence the not being to meticulous with receipts). Luck had it that I ordered everything I needed for the build and then waited for the block and heads. Prices went way up by the time I put all of this together.
I hear you, I was really torn and wanted to go with the KRE 85cc heads flowed to 290 or 315 but I just couldn't justify another 3K with gaskets, bolts maybe pushrods and then didn't trust myself to crack the motor open plus just spending 7500.00 that I didn't plan on and I had so much stuff to put around the motor. Called Butler and they said I wouldn't gain much HP over what they did to them as they flow 220-240 with all good parts, yes I could have sold them for a good buck but what's done is done and it's scary enough (y)
 
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