Nice cam that Howard’s. That was a good find buy GE.
Stockish 340 upgrades, cam needed
- Thread starter oldkimmer
- Start date
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That cam was actually the one I was going to recommend from the start until “GigantoMania” to match CNC heads set in. That one or a 218/226 grind that looks like a high lift regrind stock 340 cam with a .904 specific ramp rate.
Howards Cams Hydraulic Flat Tappet Camshafts 711651-10
In a 9:1-9.5:1 street engine with decent heads (J or 302 castings with emphasis on flow to .500), either of these cams should make a very good performer with good street manners.
Howards Cams Hydraulic Flat Tappet Camshafts 711651-10
In a 9:1-9.5:1 street engine with decent heads (J or 302 castings with emphasis on flow to .500), either of these cams should make a very good performer with good street manners.
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oldkimmer
does the top of you piston look like this?
If so i have a warning for you.
Them are deep valve reliefs!
HOWEVER, there is a shelf that goes straight up in that valve relief to the flat surface on top. I didn't have enough valve to piston clearance with the mopar performance cam(.474/280 cam)
When i made the valve relief keep the same angle all the way up to the flat top of the piston. there was plenty of clearance. in fact i couldn't make it hit the piston pushing the exhaust valve all the way down.
Just a little fyi
does the top of you piston look like this?
If so i have a warning for you.
Them are deep valve reliefs!
HOWEVER, there is a shelf that goes straight up in that valve relief to the flat surface on top. I didn't have enough valve to piston clearance with the mopar performance cam(.474/280 cam)
When i made the valve relief keep the same angle all the way up to the flat top of the piston. there was plenty of clearance. in fact i couldn't make it hit the piston pushing the exhaust valve all the way down.
Just a little fyi
Yes, exactually. Do u mean where I used the jiffy marker? Kim
Thanks for the the information! From what I could tell on the similar build I’ve been offering guidance on (.040 over stock stroke 340), I strongly suspected that we’d have to get the reliefs recut. It’s a certainty it’s getting either an XE274 H or XE274HL, as he’s recently acquired both cams. It’s presently coming in right at 10:1 with some 894X heads with Milodon stainless valves. Do you know about how many cc’s you picked up by opening the valve reliefs up to that point?
This is how I got the pistons. The motor came with my Duster that I went big block in. Doesn’t look like anything has been done to the pistons. Kim
Ya you're right about hate quicker!!!!!
So what's heavier a pound of feathers or a pound of butter?Ya you're right about hate quicker!!!!!
I will do that. I'm old but not old enough to stop learning. And thank you for not telling me I don't know ****. There sure are a lot of haters out there.@LO23M8B
I use to believe this as well, and all that has been said about it, made sence with the alu dissipating heat and all.
Go become a member of Motor Trend On Demand if you are not already. it like 3 buck a month!
Then watch this video from Engine Masters: They take and identical head that was available in alu and iron.
It was a vary well sorted out test. Worth the 3 buck membership and all the great other programs(I'm sounding like a salesman)
ENGINE MASTERS: Season 5, Episode 57 - Iron vs. Aluminum Heads: A Study of Heat | MotorTrend
Yes But not to that extream!
Just level off that shelf straight across........
No my compression example number was after i cleaned it up. them reliefs are hug and will support a lot of lift. however that shelf wouldn't let you get to the Valve reliefs the vavle hits that shelf. it didn't add a hole lot of cc to it.
just lay back that shelf vvvvvvvvvvvvvvvvvvvvvvvv
These chambers are not CNC. Kim
You might want to look up the definition of effectively. I never said it would change the cylinder pressure.
PRH
Well-Known Member
Exactly.
Be nice to get rid of that sharp ridge even if you didn’t need the room.
Wouldn’t even be 1cc removed.
PRH
Well-Known Member
The reliefs are part of the forging, the ridge is just left over from machining the piston tops to the specified height.
Okay, thank y’all for the information! It looks like settling a 45 degree cut starting in the bottom corner toward the center of the piston will work great for that.
Thanks guys I’ll go that. Kim
I just took a die grinder and ground that lip off, then sandpaper it smooth
Thanks. Kim
Wyrmrider
Well-Known Member
recap
HRS 711651 265 218 .502 110 LCA garrett's third suggestion post 77
HS 711451-08 267 220 .506 Garrett Ellison 2ed suggestion post 28 ***
HRS 710461-10 273 226 .525 Garrett Ellison for 9.5 340 post 23 110LCA
340 cam 279 210 .429 2899206 intake @.006 stock early 340 was a 9.5:1 class motor
so is this a 9.5 or 10.5 build?
stock exhausts post 34
What PRH says post 45
Garrett post 46 Magnum heads, good suggestion if not no 1.7 in this budget
Post 49 Quit trying to fit the cam to the head flow not going to happen without high ratio rockers and or mushroom lifters
Match the cam to the rear gear and how the lady wants to drive it- be happy
also no 108 with stock exhaust – stick to 112 or 110 if short cam
stock exhaust hates overlap
agree with PRH has anyone cc'd these heads?
Post 71 mopowers @*** He's not going to want that 108LCA with stock exhausts
275 231 526 108 lca
XE275HL 275 231 .525 110LCA IC 64 ABDC
XE 274 H 274 230 .487
post 80 XE 274 may be an old UDHarold grind, same problems as the 268
You could” Isky tool” those pistons for left and right
#90 agree on no sharp ridges
post 2-- 68 4 speed cam NA for 3.23 gears low lift like the stock 340 cam
340 cam [email protected] 210 @.050 .429 2899206 intake @.006
Post 9 rumbles cam 11:1 360 110 lca
274 224 .538 .573 w/ 1.6
HRS 711651 265 218 .502 110 LCA garrett's third suggestion post 77
HS 711451-08 267 220 .506 Garrett Ellison 2ed suggestion post 28 ***
HRS 710461-10 273 226 .525 Garrett Ellison for 9.5 340 post 23 110LCA
340 cam 279 210 .429 2899206 intake @.006 stock early 340 was a 9.5:1 class motor
so is this a 9.5 or 10.5 build?
stock exhausts post 34
What PRH says post 45
Garrett post 46 Magnum heads, good suggestion if not no 1.7 in this budget
Post 49 Quit trying to fit the cam to the head flow not going to happen without high ratio rockers and or mushroom lifters
Match the cam to the rear gear and how the lady wants to drive it- be happy
also no 108 with stock exhaust – stick to 112 or 110 if short cam
stock exhaust hates overlap
agree with PRH has anyone cc'd these heads?
Post 71 mopowers @*** He's not going to want that 108LCA with stock exhausts
275 231 526 108 lca
XE275HL 275 231 .525 110LCA IC 64 ABDC
XE 274 H 274 230 .487
post 80 XE 274 may be an old UDHarold grind, same problems as the 268
You could” Isky tool” those pistons for left and right
#90 agree on no sharp ridges
post 2-- 68 4 speed cam NA for 3.23 gears low lift like the stock 340 cam
340 cam [email protected] 210 @.050 .429 2899206 intake @.006
Post 9 rumbles cam 11:1 360 110 lca
274 224 .538 .573 w/ 1.6
Heads have not been cc’d yet. These are Speedmaster CNC heads. 190 intake port. 2.02 and 1.60 valves. Supposed to be 65 cc chambers. The pistons are 2332 forged replacements. 040 over, so 4.080 bore. Look just like a 10.5 stock piston. Pistons are .015 above deck. Exhaust will be TTI 1 5/8 to 1 3/4 step headers. Full TTI 2 1/2 exhaust. Hughes roller rockers. Kim
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