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Here's what I designed and built - originally I wanted it to be just a strip car but later decided to put the engine into my 1968 Goat. 10.25 CR works on 93 Octane, and I tried to design for low end torque which is about what I got. Cool thread!

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400 I left it as a 2 bolt main.
2 Crank Size Used (ie 400, 455, etc) - Stroker 4.25" stroke
3 Stroker Kit Used (ie 461, 467, 471, etc) - Bore of 4.165, stroke 4.25 so I forget, around 462 or so.... But yes it was a Butler kit with Cast Crank, forged H rods and pistons.
4 Final Bore Diameter - 4.165
5 Final Deck Height -
6 Piston (Type, Make & Model) - Ross with depression to give me 10.25 CR
7 Compression Ratio (Static) - 10.25
8 Compression Ratio (Dynamic) -
9 Heads (Make & Model) - #16 Stock with Inserts, valve job, etc....
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" exhaust
11 Head Chamber Size (Actual in cc's) - 72cc if I recall
12 Head gasket thickness - .040
13 Intake to Head Port Matched? - Nope - zero porting done to heads, manifold, etc. Felpro Intake gasket.
14 Head to Exhaust Port Matched? - Nope
15 Intake (Make & Model) - Edel Performer RPM (Wanted Dual plane to try to target high torque at low RPM)
16 Exhaust Manifolds or Headers - Doug Headers
17 Exhaust Manifolds or Headers (Make & Model) - Yep above....
18 Carburetor (Make & Model) - 1976 Quadrajet with Cliff re-work - right down to new plating.... I love her very much....
19 Cam (Make & Model) - Butler CCA-BP8030SP Hyd Roller
20 Cam Specs - 236/242 at .050 .521/.540 112 LSA
21 Rocker Ratio - 1.5
22 Rocker Type (Stamped or Roller) - Roller
23 Rocker (Make & Model) - PRW-0245501
24 Push Rod Length - I forget
25 Estimated Flywheel Horse Power -
26 Dyno'd Flywheel Horse Power - 498 Max at 5,200 RPM - 600 Ft. Lbs at 4,200 RPM
27 Dyno'd Horse Power at the rear tires -
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd Roller
29 Lifter (Make & Model) - Johnson I forget numbers
30 Ignition: - DUI Distributor (Performance Distributors)


  1. Wagner PCV w Moroso Catch Can
  2. CVF Serpentine Pulley system - no A/C
  3. 1968 GTO
 

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Do you know my computer skills, I took a picture of my screen and posted it that's how Ben Franklin works 😃 it's in the tech drop down under compression calculator.
 

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Sure you can be all scientific about it but isn't seeing the lines of the computer screen trippy, by the way Mr. scientist when I click on that link the page is cut off on the right so you're not seeing the other two chamber sizes...now where did I put my Blackberry and my Bad Company cassettes 😁
 

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Sure you can be all scientific about it but isn't seeing the lines of the computer screen trippy, by the way Mr. scientist when I click on that link the page is cut off on the right so you're not seeing the other two chamber sizes...now where did I put my Blackberry and my Bad Company cassettes 😁
Sounds like another operator error my friend :ROFLMAO: Try scrolling to the right (or push the right arrow, bottom right of your key board). Sounds like the link opened in a page that was bigger than your screen. It happens sometimes, probably a setting thing on you PC. I just followed the link and it does work to give a full screen.

Wait a minute. So you were able to take a picture, add a circle around it, and then post it here but a link was a no go? They way you did it was way harder than copying the link. Maybe we gotta get you a pair of horned rimmed glasses and nerdy you up a bit.

All joking, I liked your solution to not knowing how to do something. Way better than the "I can't do it so I'm not going to try" attitude.

This may help. To insert a link:

You need to have multiple tabs open on your browser to do this (one tab where you are trying to insert the link to and the one for the other page that you are trying to link from). Click on the tab you are trying to link to, you go to the address bar at the top and place the cursor to the right of all the text (or to the very far right of the box if the text goes past the end). Click and hold the left mouse button. While still holding, drag the mouse to the left across the text so that it is all highlighted and release the button. Don't push any button yet but move the curser to anywhere on the highlighted text and push the right mouse button and a drop down should appear. Click on copy. Now go back to the tab where you were typing, preferably the GTO forum, and put your cursor where you want the link to appear, push the right mouse button again, the same drop down list should appear, click on paste. It sounds way harder than it is but when done, takes about 4 seconds to do.

Let me know if this helps, or if there's any step that doesn't make sense. I'm happy to help with what I know. Keep in mind, we have a wide range of ages and computer skills on here. If you didn't know how to do this, chances are someone else was having the same issue too.
 

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Sounds like another operator error my friend :ROFLMAO: Try scrolling to the right (or push the right arrow, bottom right of your key board). Sounds like the link opened in a page that was bigger than your screen. It happens sometimes, probably a setting thing on you PC. I just followed the link and it does work to give a full screen.

Wait a minute. So you were able to take a picture, add a circle around it, and then post it here but a link was a no go? They way you did it was way harder than copying the link. Maybe we gotta get you a pair of horned rimmed glasses and nerdy you up a bit.

All joking, I liked your solution to not knowing how to do something. Way better than the "I can't do it so I'm not going to try" attitude.

This may help. To insert a link:

You need to have multiple tabs open on your browser to do this (one tab where you are trying to insert the link to and the one for the other page that you are trying to link from). Click on the tab you are trying to link to, you go to the address bar at the top and place the cursor to the right of all the text (or to the very far right of the box if the text goes past the end). Click and hold the left mouse button. While still holding, drag the mouse to the left across the text so that it is all highlighted and release the button. Don't push any button yet but move the curser to anywhere on the highlighted text and push the right mouse button and a drop down should appear. Click on copy. Now go back to the tab where you were typing, preferably the GTO forum, and put your cursor where you want the link to appear, push the right mouse button again, the same drop down list should appear, click on paste. It sounds way harder than it is but when done, takes about 4 seconds to do.

Let me know if this helps, or if there's any step that doesn't make sense. I'm happy to help with what I know. Keep in mind, we have a wide range of ages and computer skills on here. If you didn't know how to do this, chances are someone else was having the same issue too.
It's only to small on the phone so maybe it's to big of a page for that, I didn't think that one page was it's own link. And for some reason I can't copy and paste links on my laptop only on the phone.
 

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Sure you can be all scientific about it but isn't seeing the lines of the computer screen trippy, by the way Mr. scientist when I click on that link the page is cut off on the right so you're not seeing the other two chamber sizes...now where did I put my Blackberry and my Bad Company cassettes 😁
Am I the only one thinking South Park….. Mr. Scientist…. 😂
 

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Here is my build. In addition I had the turbomatic replaced with a 5 speed tremec. Also got 2.5" duel x-pipe exhaust but apparently there was not enough space in the engine compartment to fit headers which I am not happy about. So I just have round port ram air exhaust manifolds. Maybe someone can custom make headers that will fit right if it matters. It chassis dyno'd at 364hp with max torque at 470. So probably around 430HP on the flywheel. I do get alot of compliments on how it sounds and you can hear it from a mile away. But damn thing still has the bad habit of leaking a little oil on the driveway.
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Here's mine. I'm sure the intake manifold is restricting airflow quite a bit, so I'm willing to bet it'd make a little more power with a different intake/carb setup...but I wanted dual quads.🤷‍♂️

Stroker Specs

1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used – 4.250” Eagle
3 Stroker Kit Used (ie 461, 467, 471, etc) – Butler/Ross 461
4 Final Bore Diameter - 4.155"
5 Final Deck Height – Standard Deck Height
6 Piston (Type, Make & Model) – Flat Top, Ross (-8cc)
7 Compression Ratio (Static) – 10.11:1
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) – Edelbrock D-Port Aluminum #61579
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.66" exhaust
11 Head Chamber Size (Actual in cc's) - 87cc
12 Head gasket thickness - .039” (Fel-Pro #1016)
13 Intake to Head Port Matched? - Yes
14 Head to Exhaust Port Matched? - No
15 Intake (Make & Model) – Edelbrock P65 Dual Quad #5450
16 Exhaust Manifolds or Headers - Headers
17 Exhaust Manifolds or Headers (Make & Model) – Doug’s D567 Ceramic Coated
18 Carburetor (Make & Model) – Edelbrock 500cfm AVS2 Carburetors (#1903 & #1904)
19 Cam (Make & Model) – COMP Xtreme Energy XR276HR Hyd Roller #51-423-11
20 Cam Specs - Lift: .502"/.510" | Duration: 276°/282° | LSA: 110° | RPM Range: 1800-5600
21 Rocker Ratio – 1.65
22 Rocker Type (Stamped or Roller) - Roller
23 Rocker (Make & Model) – COMP Ultra Gold Arc #19061
24 Push Rod Length – 9.300” (Smith Bros 2-Piece, Oil Restricted, 5/16”)
25 Estimated Flywheel Horse Power – N/A
26 Dyno'd Flywheel Horse Power – 434.1 HP / 531.8 FT/LBS Torque
27 Dyno'd Horse Power at the rear tires – N/A
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd Roller
29 Lifter (Make & Model) – Hy-Lift Johnson #HYL-2347
30 Ignition: - MSD Pro-Billet Ready-to-Run Distributor #8528
Tire Wheel Automotive tire Car Motor vehicle
 

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Discussion Starter · #34 ·
I added the following data points to the list in the OP. If those of you who have listed your builds can add these...it would be great.

31 Fuel Octane - ???
32 How do you get to that octane (91, 93, + additive w/brand, race fuel mix, etc) - ???
 

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Good morning. I'm starting out on a stroked Pontiac 389 build for my '65 Convertible. I've been prowling the forums here for ideas and so on. So this thread is spot on for research. Thank you to the participants.
My objective was to retain my date code correct OEM block and maintain a period correct look of an engine which could have been assembled in the early 70's when these cars were easily obtainable and hot rodded, but add modern internal technology to improve output. Motivation to do this now comes from discovery that my stock crank is cracked on several rod journals and the otherwise well running engine had become contaminated with grit when doing a carburetor swap / valley pan PCV grommet oil leak repair. I took the engine apart for cleaning after it was removed to install reproduction cast iron headers which led to magniflux inspection of the crank.

Finding the crank cracked led me to toss my rods, pistons, rings, and main bearing caps in the trash. In my opinion all were components which might have sustained historic damage because the crank had apparently been overloaded to failure by years of racing, high speed touring, and substandard (modern) fuel; despite those parts passing magniflux and dye glow inspection now. Because of modern oil issues causing accelerated flat tappet cam wear I've led myself into wanting a roller cam conversion but feel a few of my tappet bores may be quite thin to stand increased side loading. I've been aware through conversations with Ed Iskenderian back in the early 70's of Micky Thompson's efforts to buttress Pontiac tappet bore areas with filler plates and epoxy since the late 1960's, so implementing this sort of modification path became indicated. As I added up the costs associated with reinforcement of my block with 4 bolt caps, hard block cylinder filler, tappet area buttress plates, and various "normal" race engine machine work of square decking, etc to withstand increased operating forces, an aftermarket block became a more cost effective solution.

However that contradicted my initial goal of maintaining vintage hot rod period correctness. This realization is leading me to build two stroker engines. First the period correct engine to run on the street messing around, then next an all aluminum light weight engine to run more aggressively, perhaps in track day events. This decision has made head and cam selection much easier. It has also simplified decisions about porting and piston design. So this post will slant towards the first engine, an engine which would have been possible to build in the early 70's with externally visible parts one could have had made or purchased back then.

This path led clearly to Butler and Ames and their subcontractor vendors, but also includes various other companies making specialized internal parts or providing specialized processes.



1 OEM Block Size (ie 326, 389, 400, 455. etc) - retain 1965 389 cid block but upgrade with Milodon 4 bolt caps, block filler, Mega Brace from Butler, bored, decked and so on.
2 Crank Size Used (ie 400, 455, etc) - I went to SCAT for an AERA engine conference and talked to Tom Leib about cranks for Pontiac engines. He said there is no downside to using the largest stroke he makes (and provides to Butler) with rods and so on. I ordered a lightweight Pro II 4.500 inch stroke crank.
3 Stroker Kit Used The "kit" is coming from SCAT. Pro II I-beam rods at 6.700 inches. Clevite H series bearings.
4 Final Bore Diameter - 4.120 = 480 CID
5 Final Deck Height - 10.222 inches
6 Piston (Type, Make & Model) - KB 4032 Pistons to suit combustion chamber of Pontiac "670" head. 38cc dish, Gold thermal coating, and a Teflon skirt coating will be applied. Rings are Total seal gapless.
7 Compression Ratio (Static) - 9.2 to 1
8 Compression Ratio (Dynamic) - cannot calculate exactly until the camshaft is designed and then installed.
9 Heads (Make & Model) OEM Pontiac "670" castings fully ported and air flow balanced. Heat riser bowls blocked.
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" + .100" longer stems. exhaust w/hard inserts for unleaded gas conversion and bronze guides. Stud upgrade for roller rockers, fully thermal barrier coated by CALICO COATINGS.
11 Head Chamber Size (Actual in cc's) - 73cc
12 Head gasket thickness - .040
13 Intake to Head Port Matched? - Yes.
14 Head to Exhaust Port Matched? - Yes
15 Intake (Make & Model) - Using '65 OEM tripower manifold EXTRUDE HONE process applied to maximize plenum area and port match to FEL PRO gasket size 1/4 " thermal blocks with gaskets under carbs. .
16 Exhaust Manifolds or Headers - Reproduction cast iron from RAM AIR Reproductions. 2 1/2 inch to 3 " head pipes with O2 bungs and back pressure measurement taps added.
17 Exhaust system - 3" oval pipe to X oval style crossover from SPINTECH to 15" x 10" x 5" box mufflers. Front style in/out to side discharge ahead of rear tires. Entire system is thermal barrier coated by SWAIN in their "White Lightening" compound. Head pipe to X = 44 inches.
18 Carburetor (Make & Model) - OEM correct tri power with OEM RAM AIR conversion added. Jetting reworked substantially.
19 Cam (Make & Model) - Custom cam ground by Dema ELGIN CAMS mutually designed from air flow and specific engine design parameters.
20 Cam Specs -
21 Rocker Ratio - 1.6 to one projected to be used.
22 Rocker Type steel roller
23 Rocker (Make & Model) - CROWER 73624 - 16
24 Push Rod Length - unknown until engine is trial assembled and fit. Will come custom from SMITH BROTHERS in Oregon.
25 Estimated Flywheel Horse Power - 500
26 Dyno'd Flywheel Horse Power -
27 Dyno'd Horse Power at the rear tires -
28 Lifter Type - Mechanical roller
29 Lifter (Make & Model) - ISKY RED ZONE with upgrade bushings.
30 Ignition: - OEM distributor with PETRONIX upgrade.( for now )
31 Fuel - proposed 91 Octane
32 - Availability of fuel I buy race gas at the track when I need anything higher than 91. Comments from Lake Speed jr a month ago mentioned +/- 3 octane points is typical for pump gas today and it is never on the high side. Verified by dyno testing on their calibration mule engines. Also modern gas degrades from sunlight exposure within a couple of days time. Use steel cans only. So the 91 you buy is likely 88ish and maybe causing issues....... like cracked cranks.....


  1. Custom made PCV system based off a photo of dealer installed RAM AIR option and trade practices of implemented conversions meeting California Air Resources board rules in early 70's.
  2. Belts and front pulleys are all OEM.
  3. 1965 GTO convertible.
Rear tire size is P275 x 60 R 15 by BF Goodrich on OEM Corvette 8 inch Rally rims. The car has been lowered slightly. I replaced the rear axle assembly with a unit from Currie narrowed 2 inches from stock to eliminate tire rubbing with OEM zero offset 8 inch Corvette Rally rims when running a GM 12 bolt Chevelle axle. I had Wheel Vintique make a set of look-a-like Rally wheels with 1-1/4 inch negative offset in the1990's that helped a lot to minimize rubbing when running L50 x 15 BFG tires (now long obsolete). But Wheel Vintique were unable to provide a 5th (spare tire) rim in the 2020's after a wait of over a year and a half for its production. I canceled that order after driving down there for a phyical plant inspection to confirm I'd been lied to about my rims being stuck in their powder coating department (for 8 months) when they had not even been welded up. I instead had an axle built so I could run the easily available Corvette zero offset 8" rim which also should solve a number of potential issues related to breaking GM 12 bolt axles vs the aluminum NASCAR Ford style center section with STRANGE ENGINEERING axles built for my Currie axle. I'm not a drag racer, and have no idea how this tire will hook up with a more powerful engine. The rear suspension is boxed and has a sway bar. OEM retrofit frame braces have been installed. My shock mounts are upgraded but have essentially OEM geometry. I'm open to comments about how others have set up rear suspensions for drag racing vs. road racing (which I am fully familiar with). Front tire size is P255 x 60 R 15 on OEM spindles with a 4 wheel power disc brake conversion.
 

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Good morning. I'm starting out on a stroked Pontiac 389 build for my '65 Convertible. I've been prowling the forums here for ideas and so on. So this thread is spot on for research. Thank you to the participants.
My objective was to retain my date code correct OEM block and maintain a period correct look of an engine which could have been assembled in the early 70's when these cars were easily obtainable and hot rodded, but add modern internal technology to improve output. Motivation to do this now comes from discovery that my stock crank is cracked on several rod journals and the otherwise well running engine had become contaminated with grit when doing a carburetor swap / valley pan PCV grommet oil leak repair. I took the engine apart for cleaning after it was removed to install reproduction cast iron headers which led to magniflux inspection of the crank.

Finding the crank cracked led me to toss my rods, pistons, rings, and main bearing caps in the trash. In my opinion all were components which might have sustained historic damage because the crank had apparently been overloaded to failure by years of racing, high speed touring, and substandard (modern) fuel; despite those parts passing magniflux and dye glow inspection now. Because of modern oil issues causing accelerated flat tappet cam wear I've led myself into wanting a roller cam conversion but feel a few of my tappet bores may be quite thin to stand increased side loading. I've been aware through conversations with Ed Iskenderian back in the early 70's of Micky Thompson's efforts to buttress Pontiac tappet bore areas with filler plates and epoxy since the late 1960's, so implementing this sort of modification path became indicated. As I added up the costs associated with reinforcement of my block with 4 bolt caps, hard block cylinder filler, tappet area buttress plates, and various "normal" race engine machine work of square decking, etc to withstand increased operating forces, an aftermarket block became a more cost effective solution.

However that contradicted my initial goal of maintaining vintage hot rod period correctness. This realization is leading me to build two stroker engines. First the period correct engine to run on the street messing around, then next an all aluminum light weight engine to run more aggressively, perhaps in track day events. This decision has made head and cam selection much easier. It has also simplified decisions about porting and piston design. So this post will slant towards the first engine, an engine which would have been possible to build in the early 70's with externally visible parts one could have had made or purchased back then.

This path led clearly to Butler and Ames and their subcontractor vendors, but also includes various other companies making specialized internal parts or providing specialized processes.



1 OEM Block Size (ie 326, 389, 400, 455. etc) - retain 1965 389 cid block but upgrade with Milodon 4 bolt caps, block filler, Mega Brace from Butler, bored, decked and so on.
2 Crank Size Used (ie 400, 455, etc) - I went to SCAT for an AERA engine conference and talked to Tom Leib about cranks for Pontiac engines. He said there is no downside to using the largest stroke he makes (and provides to Butler) with rods and so on. I ordered a lightweight Pro II 4.500 inch stroke crank.
3 Stroker Kit Used The "kit" is coming from SCAT. Pro II I-beam rods at 6.700 inches. Clevite H series bearings.
4 Final Bore Diameter - 4.120 = 480 CID
5 Final Deck Height - 10.222 inches
6 Piston (Type, Make & Model) - KB 4032 Pistons to suit combustion chamber of Pontiac "670" head. 38cc dish, Gold thermal coating, and a Teflon skirt coating will be applied. Rings are Total seal gapless.
7 Compression Ratio (Static) - 9.2 to 1
8 Compression Ratio (Dynamic) - cannot calculate exactly until the camshaft is designed and then installed.
9 Heads (Make & Model) OEM Pontiac "670" castings fully ported and air flow balanced. Heat riser bowls blocked.
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.77" + .100" longer stems. exhaust w/hard inserts for unleaded gas conversion and bronze guides. Stud upgrade for roller rockers, fully thermal barrier coated by CALICO COATINGS.
11 Head Chamber Size (Actual in cc's) - 73cc
12 Head gasket thickness - .040
13 Intake to Head Port Matched? - Yes.
14 Head to Exhaust Port Matched? - Yes
15 Intake (Make & Model) - Using '65 OEM tripower manifold EXTRUDE HONE process applied to maximize plenum area and port match to FEL PRO gasket size 1/4 " thermal blocks with gaskets under carbs. .
16 Exhaust Manifolds or Headers - Reproduction cast iron from RAM AIR Reproductions. 2 1/2 inch to 3 " head pipes with O2 bungs and back pressure measurement taps added.
17 Exhaust system - 3" oval pipe to X oval style crossover from SPINTECH to 15" x 10" x 5" box mufflers. Front style in/out to side discharge ahead of rear tires. Entire system is thermal barrier coated by SWAIN in their "White Lightening" compound. Head pipe to X = 44 inches.
18 Carburetor (Make & Model) - OEM correct tri power with OEM RAM AIR conversion added. Jetting reworked substantially.
19 Cam (Make & Model) - Custom cam ground by Dema ELGIN CAMS mutually designed from air flow and specific engine design parameters.
20 Cam Specs -
21 Rocker Ratio - 1.6 to one projected to be used.
22 Rocker Type steel roller
23 Rocker (Make & Model) - CROWER 73624 - 16
24 Push Rod Length - unknown until engine is trial assembled and fit. Will come custom from SMITH BROTHERS in Oregon.
25 Estimated Flywheel Horse Power - 500
26 Dyno'd Flywheel Horse Power -
27 Dyno'd Horse Power at the rear tires -
28 Lifter Type - Mechanical roller
29 Lifter (Make & Model) - ISKY RED ZONE with upgrade bushings.
30 Ignition: - OEM distributor with PETRONIX upgrade.( for now )
31 Fuel - proposed 91 Octane
32 - Availability of fuel I buy race gas at the track when I need anything higher than 91. Comments from Lake Speed jr a month ago mentioned +/- 3 octane points is typical for pump gas today and it is never on the high side. Verified by dyno testing on their calibration mule engines. Also modern gas degrades from sunlight exposure within a couple of days time. Use steel cans only. So the 91 you buy is likely 88ish and maybe causing issues....... like cracked cranks.....


  1. Custom made PCV system based off a photo of dealer installed RAM AIR option and trade practices of implemented conversions meeting California Air Resources board rules in early 70's.
  2. Belts and front pulleys are all OEM.
  3. 1965 GTO convertible.
Rear tire size is P275 x 60 R 15 by BF Goodrich on OEM Corvette 8 inch Rally rims. The car has been lowered slightly. I replaced the rear axle assembly with a unit from Currie narrowed 2 inches from stock to eliminate tire rubbing with OEM zero offset 8 inch Corvette Rally rims when running a GM 12 bolt Chevelle axle. I had Wheel Vintique make a set of look-a-like Rally wheels with 1-1/4 inch negative offset in the1990's that helped a lot to minimize rubbing when running L50 x 15 BFG tires (now long obsolete). But Wheel Vintique were unable to provide a 5th (spare tire) rim in the 2020's after a wait of over a year and a half for its production. I canceled that order after driving down there for a phyical plant inspection to confirm I'd been lied to about my rims being stuck in their powder coating department (for 8 months) when they had not even been welded up. I instead had an axle built so I could run the easily available Corvette zero offset 8" rim which also should solve a number of potential issues related to breaking GM 12 bolt axles vs the aluminum NASCAR Ford style center section with STRANGE ENGINEERING axles built for my Currie axle. I'm not a drag racer, and have no idea how this tire will hook up with a more powerful engine. The rear suspension is boxed and has a sway bar. OEM retrofit frame braces have been installed. My shock mounts are upgraded but have essentially OEM geometry. I'm open to comments about how others have set up rear suspensions for drag racing vs. road racing (which I am fully familiar with). Front tire size is P255 x 60 R 15 on OEM spindles with a 4 wheel power disc brake conversion.
So no problems with that big of a tire on the front? My 215/70/15 are really close at the points now but I have 1" lowering springs with iron heads. I would be happy if I could fit 245/60 for some extra width but I don't think it's going to work and 235/60 get to short looking. My 215/70 are almost even maybe slightly below the opening trim and looks good.
 

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Ah, no problems now. I recall years ago I slightly modified the front wheel well opening to soften the "point" at the rear arch and roll the lip. If you can access the Pontiac Club "Legendary Lines" news letter there are photos of my car showing the tire / wheel well in the article written for their December 2021 issue. The car is lowered in the front also for Auto X use back in the day. I like how it sits so left it. I plan to replace the OEM spindles with, maybe, some taller Camaro or Corvette ones someday to improve the caster / camber curve..... someday.. I need to get a pair of engines built first. Thanks for asking. Ladd
 

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Ah, no problems now. I recall years ago I slightly modified the front wheel well opening to soften the "point" at the rear arch and roll the lip. If you can access the Pontiac Club "Legendary Lines" news letter there are photos of my car showing the tire / wheel well in the article written for their December 2021 issue. The car is lowered in the front also for Auto X use back in the day. I like how it sits so left it. I plan to replace the OEM spindles with, maybe, some taller Camaro or Corvette ones someday to improve the caster / camber curve..... someday.. I need to get a pair of engines built first. Thanks for asking. Ladd
Ah that's your secret, I thought that sounded big up there 👍
 

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1 OEM Block Size (ie 326, 389, 400, 455. etc) - 1970 400 block YD
2 Crank Size Used (ie 400, 455, etc) - Stroker 4.25" stroke
3 Stroker Kit Used (ie 461, 467, 471, etc) - Butler 467 4.181, -8cc
4 Final Bore Diameter - 4.181
5 Final Deck Height - zero decked 10.223
6 Piston (Type, Make & Model) - butler /ross stroker kit -8cc
7 Compression Ratio (Static) - 10.7
8 Compression Ratio (Dynamic) - 71 abdc 8.2
9 Heads (Make & Model) - edelbrock 61579 stock valves and spring with cc chamber and port work. Milled to achieve 82cc
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.66" exhaust
11 Head Chamber Size (Actual in cc's) - 82cc
12 Head gasket thickness - .038
13 Intake to Head Port Matched? - yes
14 Head to Exhaust Port Matched? - No
15 Intake (Make & Model) - Edelbrock 7156
16 Exhaust Manifolds or Headers - ram air III
17 Exhaust Manifolds or Headers (Make & Model) -
18 Carburetor (Make & Model) - 1970 qjet 750 recalibrated by Ken from everyday performance to work with this engine.
19 Cam (Make & Model) - crower 60243
20 Cam Specs - 284/290 228/235 112LSA degreed to 108 centerline 479/494
21 Rocker Ratio - 1.52
22 Rocker Type (Stamped or Roller) - comp cam pro magnum 1451-16 stamped steel roller tip. (Little noisy) zero lash half turn
23 Rocker (Make & Model) - 1451-16 1.52
24 Push Rod Length - 9.150 Butler 5/16", .116" Wall, 1pc Chromoly Pushrods by Smith Brothers
25 Estimated Flywheel Horse Power - ? Night and day difference from the original YS 400
26 Dyno'd Flywheel Horse Power -
27 Dyno'd Horse Power at the rear tires -
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd flat tappet crower cam saver lifters
29 Lifter (Make & Model) - crower cam saver lifters
30 Ignition: - stock point type rebuilt and curved by Everyday Performance. 12 initial, advance starts at 800rpm returns to zero 750, 6, 1000rpm, 10 1200 rpm, 14 1600 rpm, 20 3000 rpm. 32 total 8 degree limit on vacuum advance.

I know it has more but the car is all stock original don't want to push the limit. Stock original 400 with a 2800 stall 3.55 gear, M/E wagner PVC, 17" vacuum Idle.
 

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@sameold01 I was hoping you were going to post on here. I know yours has been in the works for a while. Sounds like a very healthy build. Did you have Butler do the port work on the heads, a local shop, or did you tackle them yourself?
 
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