What About Edelbrock 340 Heads?

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harrisonm

harrisonm

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I have been thinking about getting a pair of Edelbrock Performer RPM heads for my 340 and having them professionally ported. Here is my question. Every time a member asks which head to use, it seems that everybody says W2, W5 Brodix, blah, blah, blah. I don't think I have ever heard anyone say, "Buy a pair of Edelbrock heads and have them ported." Is there a reason why nobody seems to recommend the Edelbrock Performer RPM heads?
 
IDK, but
I have a pair of OOTB closed chamber Eddies on my 367 streeter. Car went 93 in the 1/8th at 3467 pounds, with a 230cam. I was real happy. They have made it to over 100,000 miles now, and still going.

Edit: At 10.9Scr, car is very snappy with a 3.09x3.55 starter gear, and makes enough torque to initiate a spin at part throttle with 295BFG TAs. It will carry the spin to past the legal speed limit anywhere in Manitoba. It will easily initiate that spin in 1.92 second gear at 50mph(4200rpm) with just a foot stomp.
I have heard that BFGs ain't much for traction, so I include this; The car does the same with nearly fresh BFG 325/50-15 CompTA DragRadials, so I'm still a happy guy.
The bottom end is about as plain as can be; just a basic 360@040over with stock crank,stock rods,ARP fasteners,and KB107s at .005 pop-up, +/- .0015.
I run it at 205*F, and fresh cold air down the top, TTIs and with twin full length 3inchers. I got no regrets about the hole in the hood. I run the air filter on top of the hood, unconventional I know, with a large-plenum insulated box under the hood connecting it to the airhorn. No scoop.
93mph IMO is pretty good with already five year old heads, and probably close to 50,000 miles at the time.
IDK where the power comes from.
 
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AJ/FormS said:
IDK, but
I have a pair of OOTB closed chamber Eddies on my 367. Car went 93 in the 1/8th at 3467 pounds, with a 230cam. I was real happy. They have made it to over 100,000 miles now, and still going.
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love real testaments :)
 
For a street performance/weekend warrior drag car, dollar for dollar a set of well ported Edelbrock heads are very tough to beat. Realize, there is always going to be a performance difference between an offset rocker head, and a standard port head. The performer RPM head was designed as a performance upgrade to the stock head, not as a race head. In this capacity they work great, also at a much lower cost than a set of well ported W2/W5 type head with all the specialized parts.
 
curious to reasons.... why would somebody buy the Indy LA -X head from hughes vs the eddies..... ?????
 
may I ask what you r doing have u worn anything out on your engine what motor u have and what u want to do. what I read was greek. me 100% usaf dav. I see a little pic of a cuda year? . I show one race other notchback. what r you needing. may I help . me and am skinny block (smallblock) I saw the last statement from someone to u. last statement was over 100k and racing this motor. sir mopar is good but may I place my sole there what is this costing you. ?. part of what I am responding to is a posted conversasion. may ask what are u having fun with. b cool I race 340 have1 340-6 4speed 1 340 auto and 1440-6 auto. and a million parts. 6yrs n usaf fuel sys mech. got hurt went flight facilities. runway eguip. but what u up to was something breaking. $ somebody is gitting it. urs. holler back at me . communicate. not my $. I have 1 68 cuda I sec. owner 383s. one 67 I made into 340 6-barrel 4sp o notchback. old and mine from 14. but 68 lady bought new she died I bought . stop call or holler .
 
mam this late I read all . 340 850 430 dart. I bet any time. aint' lost yet. come on is the answer
 
harrisonm said:
I have been thinking about getting a pair of Edelbrock Performer RPM heads for my 340 and having them professionally ported. Here is my question. Every time a member asks which head to use, it seems that everybody says W2, W5 Brodix, blah, blah, blah. I don't think I have ever heard anyone say, "Buy a pair of Edelbrock heads and have them ported." Is there a reason why nobody seems to recommend the Edelbrock Performer RPM heads?
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In addition to Cpearce, which was very accurate, a lot has to do with goals of the plan on the upgrade. I highly recommend ported Edelbrocks. However, there are also other choices that may fit the bill cheaper. There is some talk going on at another thread and Promax came up with there CNC “Shocker” head with 185cc intake runner flowing at 285cfm for $2,025. They also come with a 2.08 intake valve.

If you already have the Edelbrock head, there’s a few places to send it to.
Modern cylinderhead for there CNC program.
(Probably the best in the country.)
Ryan @ Shadeydell in Pa. does really nice work as well.

Start adding costs up and know the level of power possible with said head flows. Here you’ll find the MP W series heads stomp the current aftermarket “Stock Replacement Cylinderhead” a new mud hole. M
They are pricey like all the others are but there power level should be much greater than the stock replacement heads. At this point as well, nobody purchases a W series head and goes mello on the rest. Your really out to make the most of a combo with a W head. If not, don’t bother. The Edelbrock and other heads will rock the street, no problem. But they are performance limited. And cheaper, As such.
 
Oh! Remember the W2’s came out in 1974 and was used in NASCAR & Super Stock drag racing. The W5’s are a rectangle port copy of the W2’s.
Hard to find and a gamble on porting since the foundry did a crap job with crappier aluminum.

If you get a set that will port out to the max, Whoa! Watch out. 320cfm plus is possible.
 
318willrun said:
curious to reasons.... why would somebody buy the Indy LA -X head from hughes vs the eddies..... ?????
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Can you get edelbrock to flow this? I,m very happy with my indy x rhs heads. Pushing my 3080-3100 wagon into 10:69 with a 408a.

received_861562533959827.jpeg


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SwedishViking said:
Can you get edelbrock to flow this? I,m very happy with my indy x rhs heads. Pushing my 3080-3100 wagon into 10:69 with a 408a.
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Your flow chart is looking a bit different since it doesn't display the lift of the valve in inches but numbers instead.
But the sheer flow numbers look really good and very similar to a well ported Edelbrock head.
Flow given at lift of the valve would still be interesting, like how much flow at .400?

And, err, what kinda wagon is that?
 
stixx said:
Your flow chart is looking a bit different since it doesn't display the lift of the valve in inches but numbers instead.
But the sheer flow numbers look really good and very similar to a well ported Edelbrock head.
Flow given at lift of the valve would still be interesting, like how much flow at .400?

And, err, what kinda wagon is that?
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Flow at 400 is about the 10 scale. So thats about 255-260cfm.
My valiant wagon with a lose converter that has about 13-15% slip

received_1739857889603446.jpeg
 
I have a set of OOTB Eddie's on my 273 Commando motor. Big difference over the stock heads for sure! I did have to notch the block for valve clearance. 65'
 
OP, be sure you get the Edelbrocks you want. The '340' version are essentially an 'open' style chamber, with a 4+" round recess milled in them. They can be used with the stock 340 pistons and block where the pistons tops protrude approx .018" with any thickness of head gaskets. But you can't achieve a quench gap with them and the stock type pistons.

The 'regular' Eddie heads have a closed chamber, but if you have a the protruding 340 stock type pistons, you need a thicker head gasket. Something in the range of .055" will do nicely and you will have a nice quench gap.

My son and I are very happy with the ones we put on his 'cuda. It is a street only machine, and we just had the below-the-seat area opened up a bit and smoothed on a Serdi machine. Otherwise, OOTB, easy HP up to the high 300's or around 400-ish range, which is where we wanted to be. And less worries over detonation with the cooler AL than with iron if you want to push the DCR levels up for low end torque.
 
harrisonm said:
I have been thinking about getting a pair of Edelbrock Performer RPM heads for my 340 and having them professionally ported. Here is my question. Every time a member asks which head to use, it seems that everybody says W2, W5 Brodix, blah, blah, blah. I don't think I have ever heard anyone say, "Buy a pair of Edelbrock heads and have them ported." Is there a reason why nobody seems to recommend the Edelbrock Performer RPM heads?
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To be honest YES there is. Edelbrock's quality control dept must have been fired or farmed out overseas. I will NEVER buy a set of Mopar Edelbrock heads again EXCEPT possibly the newer Victor head. It comes CNC'd and I will port it some more. I have pictures of the Promaxx head and an Edelbrock head and the ProMaxx head is 10 times nicer. The pictures are in the post about TrickFlow heads which I'm betting will be VERY nice. I've bought a lot of Edelbrock Performer heads and won't be doing so again unless I port a set for a Friend and he insists on running them.
 
Hang on nm9
I wonder if
you couldn't put the closed chamber heads on the 340 pop ups by shaving the pistons just enough to use the .039 FelPros. There's your Q. And your compression.

Of course you know me, I'd slap those closed chamber heads right down on top of the .018 pop ups, and with .039 Fellprs still, for a Q of .021,lol. I already ran that with my KB107s at zero-deck and .020 gaskets, Man that was a wicked whap-whap in the idle. But the .020 gaskets were already crawling into the valley about 7 months after the install. I just caught them at season's end tear-down.
And seeing that, I switched to the FelPros and popped the pistons up another .005 for a lil less radical Q of .034. Then I increased the minimum running temp to 205 from 180. Badaboom.

But that said. I thought the 340 oem slugs came up a lil higher?
Back in 74ish, I slapped some 69 318 heads right on top of those 340 slugs, and ran a factory 318 cam in it. That was my first "hop-up". And a winner to be sure.I have no idea what the Q was, but I still have that engine, now all tore down, and packed up in the back shed. You know what a hi-compression 340 sounds like with a 318 cam, and idling at 500rpm in gear?; thoop-thoop-thoop-thoop-thoop-thoop.........and, the hood and fenders are keeping time lol.
 
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Sure you could mill the pistons..... Lots of things you can do to adjust piston height. I was just speaking for general info.

I would not ever run .021 gap....... long term on the street.... or even short term myself. The local track guys go down to .025" minimum at times but not regularly...things wear, pistons rock, clearances change at high loads, gap goes down. Seems to me to be quite a risk for an unknown increase in benefit from the quench/squish gap.

I've never seen any info on benefit vs gap...just numbers above which you probably won't get any benefit. I have never seen this effect characterized, but sure have not seen everything! It would be great if someone had such info and could share it.
 
I have said it before,Edelbrock RPM heads are fine for what they are intended to do.
But think long and hard before you buy the 340 version,its much smarter to either change the shortblock to work with the regular RPMs or put thicker headgaskets under them.
 
It’s great to run as much quench as you can but there is a area where you have to realize that the rod stretches and how much and when is based on not just the material but the quality of it, how everything was machined and altered.

It just gets to risky after awhile. It doesn’t make sense to push it especially in the street. I’ve run .030 quench and that was just fine enough. Normally it’s .039/.040 but not more than .050 where it is said that’s the most away you can run it before the bennifts are lost.
 
rumblefish360 said:
It just gets to risky after awhile. It doesn’t make sense to push it especially in the street. I’ve run .030 quench and that was just fine enough. Normally it’s .039/.040 but not more than .050 where it is said that’s the most away you can run it before the bennifts are lost.
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Thanks, that is pretty much where I am at too.
 
1Fast340 said:
I have said it before,Edelbrock RPM heads are fine for what they are intended to do.
But think long and hard before you buy the 340 version,its much smarter to either change the shortblock to work with the regular RPMs or put thicker headgaskets under them.
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I'm curious to hear your reasoning for this. And YES I run a 300.00 damaged set I bought and they are still on my Sons 360 right now.
 
pittsburghracer said:
I'm curious to hear your reasoning for this. And YES I run a 300.00 damaged set I bought and they are still on my Sons 360 right now.
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Since i love to beat the dead horse.
That chamber is stupid, either get the shortblock right with a set of zerodeck pistons and adjust the head to make the desired compression and get good squish. As a nice bonus you can swap heads later on if you desire to do so on the same shortblock,it also means that if you blow up the shortblock and your heads survive you can slip a normal shortblock without stupid popup pistons under them and keep you squish.
The only acceptable reasons to run popup pistons is if you already have them or you are racing in a class that requires them. all other scenarios get a closed chamber head unless you already have a open chamber head.

Its not that they dont work,its that they are a stupid limitation for future changes .
 
1Fast340 said:
Since i love to beat the dead horse.
That chamber is stupid, either get the shortblock right with a set of zerodeck pistons and adjust the head to make the desired compression and get good squish. As a nice bonus you can swap heads later on if you desire to do so on the same shortblock,it also means that if you blow up the shortblock and your heads survive you can slip a normal shortblock without stupid popup pistons under them and keep you squish.
The only acceptable reasons to run popup pistons is if you already have them or you are racing in a class that requires them. all other scenarios get a closed chamber head unless you already have a open chamber head.

Its not that they dont work,its that they are a stupid limitation for future changes .
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yada yada yada on Quinch. My 408 with flat-top piston ran low 9.70's@2860 pounds in my Duster, 10.08@3200 pounds in my Sons Duster. Now they are on his stock crank flat-top pistons combo running 6.54@3200 pounds. That's around 10.30's or better in the 1/4. No tricks, no bells, and zero whistles. Ohhh and neither decks were cut on the blocks.
 
pittsburghracer said:
yada yada yada on Quinch. My 408 with flat-top piston ran low 9.70's@2860 pounds in my Duster, 10.08@3200 pounds in my Sons Duster. Now they are on his stock crank flat-top pistons combo running 6.54@3200 pounds. That's around 10.30's or better in the 1/4. No tricks, no bells, and zero whistles. Ohhh and neither decks were cut on the blocks.
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Flat top pistons are sitting where in the block? With how thick a gasket?
Thanks.
 
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