#'s Matching 340 build

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Pushrod length check. Thrust clearance came in @ .006". Monday the rings get filed and the JE pistons go on the rods. J.Rob

GB340Pushrodcheck.jpg
 
Pushrod length check. Thrust clearance came in @ .006". Monday the rings get filed and the JE pistons go on the rods. J.Rob

View attachment 1715597366
I HAVE A NUMBERS MATCHING 340 SITTING IN MY GARAGE how much value if any is lost if i put in new forged. crank rods and pistons when I rebuild it , all quality parts engine has been sitting in a temp and humidity controlled garage for 15 years
 
I settled on this little guy for camshaft duties.
Comp 20-309-4
Magnum Muscle
Camshaft Lifter Style
Hydraulic Flat Tappet
Advertised Intake Duration
268
Intake Duration at 0.050 in
222
Advertised Exhaust Duration
276
Exhaust Duration at 0.050 in
226
Intake Lift
0.464 in
Exhaust Lift
0.464 in
Lobe Separation Angle
110 Degrees
Operating Range RPM Lower
1800 RPM
Operating Range RPM Upper
5800 RPM
Manufacturer Grind Number
268AH-10
Material
Cast Iron
Color
Natural
Finish
Natural
Quantity
Each
Note
Hydraulic Flat Tappet - Magnum Muscle: Factory I.D. #2899206

J.Rob
 
I HAVE A NUMBERS MATCHING 340 SITTING IN MY GARAGE how much value if any is lost if i put in new forged. crank rods and pistons when I rebuild it , all quality parts engine has been sitting in a temp and humidity controlled garage for 15 years

who would know F.A.S.T
 
I settled on this little guy for camshaft duties.
Comp 20-309-4
Magnum Muscle
Camshaft Lifter Style
Hydraulic Flat Tappet
Advertised Intake Duration
268
Intake Duration at 0.050 in
222
Advertised Exhaust Duration
276
Exhaust Duration at 0.050 in
226
Intake Lift
0.464 in
Exhaust Lift
0.464 in
Lobe Separation Angle
110 Degrees
Operating Range RPM Lower
1800 RPM
Operating Range RPM Upper
5800 RPM
Manufacturer Grind Number
268AH-10
Material
Cast Iron
Color
Natural
Finish
Natural
Quantity
Each
Note
Hydraulic Flat Tappet - Magnum Muscle: Factory I.D. #2899206

J.Rob

That's supposed to be a good grind.
 
I HAVE A NUMBERS MATCHING 340 SITTING IN MY GARAGE how much value if any is lost if i put in new forged. crank rods and pistons when I rebuild it , all quality parts engine has been sitting in a temp and humidity controlled garage for 15 years

I say zero. No one would know. Until they opened up the engine many years from now.
 
Thanks then i'll do it and keep all the old parts to sell with the car-engine

You could put a stroker in it and no one would know.

Well... maybe until they drove it.
 
You could put a stroker in it and no one would know.

Well... maybe until they drove it.
been there done that , at 100 + miles a day i'm looking for a little better gas mileage maybe i'll upgrade the parts to get maximum mpg as it is now i use 3/4 of a tank daily , i want to go 3 days before i have to put gas in the tank . tired of putting gas in daily
 
Reduce the cam size down to or close to the 2bbl. cam and add 2.76 gears for the long Hwy. trips. Everything else will be in the tune. I found the MSD to be helpful in adding mileage as long as the rpms stay below 3K.
 
Reduce the cam size down to or close to the 2bbl. cam and add 2.76 gears for the long Hwy. trips. Everything else will be in the tune. I found the MSD to be helpful in adding mileage as long as the rpms stay below 3K.

I've gotta pretty big update to share. I was able to get this little stock stroke deal together finally AND get it on the dyno for breakin and a few prelim testing. I did use some sweet Trend pushrods in 7.400' x 8 and 7.450" x 8 due to the exhaust valves being a little longer which came in today. I'm working on a video to show some of the break in process that I like to use. For now here it is in all of its #'s matching glory. J.Rob
 
I've gotta pretty big update to share. I was able to get this little stock stroke deal together finally AND get it on the dyno for breakin and a few prelim testing. I did use some sweet Trend pushrods in 7.400' x 8 and 7.450" x 8 due to the exhaust valves being a little longer which came in today. I'm working on a video to show some of the break in process that I like to use. For now here it is in all of its #'s matching glory. J.Rob


Ok, I’m a bit confused. What is the 8 part of the pushrod...the diameter? Never used Trend so maybe they have some other way to call out diameter.
 
Considering the valve spring seat pressure and Clark Kent'esque specs of the cam I figured a total of 15mins of break in were all that was needed. I put it through 3 x 5 mins break in cycles of 1800-2400 rpm under load. In between the 5 minute cycles was 10 minutes of cool down and inspection. I'm VERY paranoid when it comes to the break in period especially with a flat tappet cam and todays sub par manufacturing standards. Everything looked excellent during the break in with only a small valve cover leak onto the oil filter which took a couple turns of the vc bolt to cure. Who doesn't love the easy fixes?

I was able to perform 4 prelim pulls with the 4th up to 5800 rpm. Any guesses? J.Rob
 
Ok, I’m a bit confused. What is the 8 part of the pushrod...the diameter? Never used Trend so maybe they have some other way to call out diameter.

8 of them are 7.400" OAL and 8 of them are 7.450" OAL. Both are 5/16" x .080" wall. J.Rob
 
Forgive the GoPro editing but it still gives an idea of what 5 minutes looks like in timelapse. J.Rob

 
INTERESTED in what kind of torque and hp you get out of this 340 , we know they were underrated from the factory , can't wait ti see how yours does
 
What is this? Americas got talent? GIVE US THE NUMBERS!!!! Okay... 365 ponies
 
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