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Engine build specs?

Ive been studying up and watching tutorials on porting to make sure i dont mess anything up. Ive seen a couple flow tests of people getting up to 230cfm out of ported 906s. A basic clean up job doesn’t seem too complex.
I’m considering aluminum heads just have to see when i get to that point. Ive seen several reviews of edelbrocks that they needed some cleaning up from casting slag and such.
Im also considering upgrading rockers, rods, lifters, springs.
Last thing i wanna do is push the stock ones too far with too much lift and destroy this motor. Way too hard to find and cost too much to replace.

Im currently fixing to replace the entire suspension and all bushings. So i got my hands full. Just trying to do some research and get a game plan on the motor when i get to it.
 
[1] Rockers. Aftermarket roller rockers usually deliver their rated ratio, & some times a little more. Factory rockers generally deliver less ratio. That means less lift & less area under the curve. Whether the butt-meter would feel the difference, hard to say.
[2] Congrats on the AVS2 car, Great carbs!
From my understanding, the roller tip rockers would be the next step up from stamped. Are they worth going to or just go to true roller rockers?

Ive got about 4 Cams im comparing, 2 from Hughes, and 2 from Lunati.
Hughes 1620BL-12 @50 216/220 with 495/503 lift 112LSA
Hughes 2024BL-11 @50 220/224 with 503/513 lift 111LSA
Lunati Voodoo 10230702
@50 220/226 with 475/494 112LSA
Lunati Voodoo 10230703
@50 226/234 with 494/513

The bigger of the cams are right on the verge of needing bigger stall to my understanding. Not sure if the factory high performance is big enough.
 
Roller tip rockers might be made a bit more accurately [ ratio wise ] than mass produced stamped rockers. There might be a small gain because of less friction with the roller tip, but hard to say if the 'gain' is worth the cost. The factory rockers are very strong.
 
Back in the day, in my drag motors I ran either the Isky ductile or the old Crane Gold with the offset. The Gold Cranes were roller tip, not full roller. They held up fine for well over a thousand runs with spring pressures of 500# or more. I had a set of 440 Source rockers I planned to use on my street car, but never installed them. They appeared to be good quality, fit well on the shafts and were true on the lift. For a street car I would bet the Source rockers would be just fine. Your cam choices are pretty mild by my experience. No worries.
 
My biggest curiosity is Valve train/Cam combos.

I think that applies for most of us.
Stamped rockers usually are ok with a flat tappet hydraulic cam, as most don't have much more that 0.500" lift and the spring pressures are fairly low.
Usually, the failure is that the pushrod breaks through the rocker arm. Really just the strength and material thickness of the stamped pushrod cup in the rocker arm.
I think Mopar Performance used to sell some stamped rockers made of slightly thicker steel?
Stock and most of the entry level aluminum heads use the stock rocker arm offsets. The aluminum race heads usually run a larger offset intake rocker arm.
I think the trick flow heads use a stock offset, but different length rocker arm than stock?

Valve train is usually fairly simple when running under 6,500 RPM with most mild to moderate cam lobe profiles.
High rate of lift solid rollers with 0.700"+ lift, and 7,000+ RPM will require high end valve train parts to survive.

Engine combinations are all over the place, it really depends on application, and what compromises you make.
Example, a Race only engine would normally have very high compression, run 112+ octane race Fuel, have large cross section ports/valves, made for high RPM use, and will need frequent maintenance and parts replacement.
A street daily driver might want a smoother idle, high vacuum for power brakes, good low/mid range torque, low maintenance, use low octane pump gas.
Most of the combinations here will be somewhere in between, from pump gas performance street to (guessing), 10 second bracket 1/4 mile drag race. Usually not too much on endurance racing, but there was a recent post where a member is running the Silver State Classic.

Most recommendations are trying to show best-bang-for-the-buck value.
For me the first decision is cylinder heads. For < 500 HP, stock appearance and such the factory iron heads will work (usually needing hardened exhaust seats for unleaded gas), but depending on their condition might cost quite a bit to rebuild, but likely less than the aluminum heads unless you opt for extensive porting. When looking for the higher end power numbers, larger valve and porting will increase the cost.
Popular upgrades for around 500 HP are the 440 source stealth heads for about $1200 /pair, and they have an outward appearance that resembles the stock iron heads, and 80cc chambers. And The Edelbrock E-Street $1,500 /pair, these can be bought as 75cc version if you need higher compression.
The Edelbrock RPM heads $ 1800+ / pair are 84cc chamber, and common for 500-600+(with porting) HP engines.
I don't know too much about the Speedmaster and Procomp heads, but I hear they are copies of the Edelbrock heads?
The newer Trick Flow 240 head around $2,200 /pair are factory CNC ported and outflow the above heads. These are one of the best bang for the buck heads for 600+ HP, but they do recommend a specific Harlan Sharpe roller rocker arm set that is expensive. Others have used these with other aftermarket roller rockers too?
If you need a small chamber head to boost compression on a lower compression engine, there is the Brodix B1 B/S, 65cc chamber, but likely around $3,000+ pair once assembled and requires offset intak rocker arms (1,180 each bare without valve, springs, etc.)
The above are the most common standard port size / height (work with stock type intakes and valley tray) heads.
The Mopar Stage VI is standard port, but raised runner. I think these might need offset rocker arms too.
The Edelbrock Victor $963 (and Victor Max Wedge) each bare, again likely $3000+ pair assembled, and require offser rocker arms.

The Indy, Victor Max Wedge, Trick flow 270 heads use the larger max wedge intake port sizes. Indy and Victor use offset rockers, and the Trick Flow recommends the HS rocker arms. Expect to spend around $1,000+ on rocker arms for these heads.

All the aftermarket heads use reduced wrench head cylinder head bolts (or studs.) The bolt kits for most of the heads is around $100.
 
I agree those cams are pretty mild. I have stamped rockers on my 440 six pack running Hughes 2328BL 223/228 - 506/524 - 111LSA 108 centerline since 2009 with zero issues.
This cam is mild and my power brakes have plenty of vacuum.
Andy
 
I'm running the hughes 216/220 cam in my 9.5:1 compression 360 engine, with 1.6:1 Crane gold rocker arms. Works great for a daily driver.
 
On the Engine combination part, the cylinder head flow will give an indication of the potential horse power the engine could make, and the minimum port cross section size along with engine displacement can give an idea of the RPM where max peak torque could be if using a cam that supports that RPM.
Having cam duration that supports the same RPM as the torque peak RPM and lift to take advantage of the head flow, should create high port energy to try cramming the most air/fuel into the engine. Once there is an idea of the cam specs, the compression ratio can be adjusted to try getting the best power for the octane of fuel used.
 
I think that applies for most of us.
Stamped rockers usually are ok with a flat tappet hydraulic cam, as most don't have much more that 0.500" lift and the spring pressures are fairly low.
Usually, the failure is that the pushrod breaks through the rocker arm. Really just the strength and material thickness of the stamped pushrod cup in the rocker arm.
I think Mopar Performance used to sell some stamped rockers made of slightly thicker steel?
Stock and most of the entry level aluminum heads use the stock rocker arm offsets. The aluminum race heads usually run a larger offset intake rocker arm.
I think the trick flow heads use a stock offset, but different length rocker arm than stock?

Valve train is usually fairly simple when running under 6,500 RPM with most mild to moderate cam lobe profiles.
High rate of lift solid rollers with 0.700"+ lift, and 7,000+ RPM will require high end valve train parts to survive.

Engine combinations are all over the place, it really depends on application, and what compromises you make.
Example, a Race only engine would normally have very high compression, run 112+ octane race Fuel, have large cross section ports/valves, made for high RPM use, and will need frequent maintenance and parts replacement.
A street daily driver might want a smoother idle, high vacuum for power brakes, good low/mid range torque, low maintenance, use low octane pump gas.
Most of the combinations here will be somewhere in between, from pump gas performance street to (guessing), 10 second bracket 1/4 mile drag race. Usually not too much on endurance racing, but there was a recent post where a member is running the Silver State Classic.

Most recommendations are trying to show best-bang-for-the-buck value.
For me the first decision is cylinder heads. For < 500 HP, stock appearance and such the factory iron heads will work (usually needing hardened exhaust seats for unleaded gas), but depending on their condition might cost quite a bit to rebuild, but likely less than the aluminum heads unless you opt for extensive porting. When looking for the higher end power numbers, larger valve and porting will increase the cost.
Popular upgrades for around 500 HP are the 440 source stealth heads for about $1200 /pair, and they have an outward appearance that resembles the stock iron heads, and 80cc chambers. And The Edelbrock E-Street $1,500 /pair, these can be bought as 75cc version if you need higher compression.
The Edelbrock RPM heads $ 1800+ / pair are 84cc chamber, and common for 500-600+(with porting) HP engines.
I don't know too much about the Speedmaster and Procomp heads, but I hear they are copies of the Edelbrock heads?
The newer Trick Flow 240 head around $2,200 /pair are factory CNC ported and outflow the above heads. These are one of the best bang for the buck heads for 600+ HP, but they do recommend a specific Harlan Sharpe roller rocker arm set that is expensive. Others have used these with other aftermarket roller rockers too?
If you need a small chamber head to boost compression on a lower compression engine, there is the Brodix B1 B/S, 65cc chamber, but likely around $3,000+ pair once assembled and requires offset intak rocker arms (1,180 each bare without valve, springs, etc.)
The above are the most common standard port size / height (work with stock type intakes and valley tray) heads.
The Mopar Stage VI is standard port, but raised runner. I think these might need offset rocker arms too.
The Edelbrock Victor $963 (and Victor Max Wedge) each bare, again likely $3000+ pair assembled, and require offser rocker arms.

The Indy, Victor Max Wedge, Trick flow 270 heads use the larger max wedge intake port sizes. Indy and Victor use offset rockers, and the Trick Flow recommends the HS rocker arms. Expect to spend around $1,000+ on rocker arms for these heads.

All the aftermarket heads use reduced wrench head cylinder head bolts (or studs.) The bolt kits for most of the heads is around $100.
Im planning on sticking with hydraulic flat tappet, one of the cams listed earlier on post #22
They’re fairly mild cams but just breaking above .500 lift so i was trying to see other peoples builds and what they used in combination with those cams or similar ones.

My motor is a ‘68 440hi-perf taken out of a another car and replaced the factory 318. It was swapped before i bought it. Its a stock block and internals to my knowledge, never built.
Factory listed compression is 10:1 but from what ive read the real world compression is closer to 9.5:1
Factory cam specs is @50 208/221 450/458 lift
I wanted to stick to similar duration but about .490-.500ish lift.
Stock stall converter, 2200? I think

Id like to stick to 10:1 compression, i dont wanna get into octane sensitivity problems.
I would like to stick to entry level heads, so I guess its a comparison of stealth vs e-street. But i dont know anything about what cc chambers i need. Please advise.
Other advice I’ve received is go to chrome moly 5/16 rods and hylift johnson lifters or whatever the Cam company has listed as recommendation.
They also have springs listed so i hope they are compatible.

The goal is just a warmed up weekend cruiser, nothing radical or race oriented besides redlights haha. Id like to break the 400hp ballpark and every bit of torque it will allow

I have been doing the math to try to find a cam that is most efficient with my chosen heads lift and most of them have a lower power band that doesn’t require a bigger stall.

Thank you for the extensive reply! Its very helpful
 
I agree those cams are pretty mild. I have stamped rockers on my 440 six pack running Hughes 2328BL 223/228 - 506/524 - 111LSA 108 centerline since 2009 with zero issues.
This cam is mild and my power brakes have plenty of vacuum.
Andy
This is some of the feedback i was looking for! Thank you.
Did you have to upgrade heads or stall converter or anything else to handle that cam?
Id like to know the rest of your build specs to compare my idea to.
 
IMO your goal of 400+hp at the wheels will need more than a 'mild' build. One of my older 440 builds had a 509 cam, stock heads with larger valves & springs to match the 509, 850 holley and it only had 345hp at the wheels. I wasn't happy with that at all.
 
IMO your goal of 400+hp at the wheels will need more than a 'mild' build. One of my older 440 builds had a 509 cam, stock heads with larger valves & springs to match the 509, 850 holley and it only had 345hp at the wheels. I wasn't happy with that at all.
Well thats a bummer to hear.
I figured with 9.5:1 compression, better flowing aluminum heads, .500 lift cam swap, long tube headers, 800cfm AVS2 carb, and 3.55 gears would get me there.
 
I agree, 400 HP at the wheels is nearly 500 at the crank. That's a bit more than a "mild" build.
 
I agree, 400 HP at the wheels is nearly 500 at the crank. That's a bit more than a "mild" build.
well while i got you guys here, what else would you recommend?
Engine mileage is unknown since motor swap so im planning a entire teardown to inspect and replace.
Im trying to keep it simple to stuff that is just basically bolt on/replace upgrades.
 
Plenty of builds with dyno results for what your after:
On this site search for members:
PRheads
challenger340
IQ52
The thing that your missing is overall condition of the engine, which you won't know till its apart. If your pursuing a really nice "optimized"engine that makes max power It likely needs bored with a hone plate, the block needs decked to get it squared up with new oversized pistons and then balanced. All preferably not by someone that builds small block chevies and has no clue about mopar.
If your hoping to hone it out freshen it up and put it back together no matter what shape it's in, the results will not be the same as someone that takes time on the details. But also...if it runs good for what it is? Does it matter and who really cares?

Quite frankly I think it's a mistake to build a engine around a stock convertor. The new custom units are just awesome. They will wake up the car easier and cheaper then building a motor. And if you do both it will scream.
 
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Plenty of builds with dyno results for what your after:
On this site search for members:
PRheads
challenger340
IQ52
The thing that your missing is overall condition of the engine, which you won't know till its apart. If your pursuing a really nice "optimized"engine that makes power It likely needs bored with a hone plate, the block needs decked to get it squared up with new oversized pistons and then balanced. All preferably not by someone that builds small block chevies and has no clue about mopar.
If your hoping to hone it out freshen it up and put it back together no matter what shape it's in, the results will not be the same as someone that takes time on the details. But also...if it runs good for what it is? Does it matter and who really cares?

Quite frankly I think it's a mistake to build a engine around a stock convertor. The new custom units are just awesome. They will wake up the car easier and cheaper then building a motor. And if you do both it will scream.
I dont have any problem with changing the convertor, i mean im gonna have it apart anyways.

I don’t exactly understand how to select them, such as a tight or loose one or if diameter matters. I do understand stall ratings and supposed to get one 300rpm above start of power band according to what i read.

There’s not many engine builders around here so thats part of my problem, closest is probably Oklahoma City or Wichita Falls. Several machine shops around here but they just build parts not engine work.
So im a little worried about cost of machine work since i dont have any buddy connections with a shop and trusting them to not try to tack on extra charges for work i didnt actually need.
 
If there's not much cyl wear, ball hone it, send the crank out for a polish or grind, slap her back together.
It should be the .055 down pistons. Compression will be good.
 
By going with a tight 9 1/2" convertor. You could potentially go from a 2200 now ...to a 4000 stall. Yet if set up correctly by the convertor shop cruising with the 9 1/2" in town and on the highway would act similiar to the stock 2200. It may even slip less. That is what makes it tight. It IS the best of both. The 2200 does nothing better other then selling it for iron cause it's heavy or if it's for a truck.

Now that you have a "real" performance convertor buy a cam with some duration move your power peak higher and make some horsepower!

I don't buy picking a convertor 300rpm above the torque peak. I would get as high of rpm flash as I could but not slip with your 3.55s cruising. Best to call a company and get the convertor built for your car...not order one and hope you like it.

Some shops can make a 10" work...but in most case the 9 1/2 is hard to beat. Also fits a 500hp engine very well.

A example of a loose convertor is in our drag car. It's a 9" turbo action 5000 stall. The car barely moves until 4000. It cooks the oil on the street because it slips so bad.
 
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By going with a tight 9 1/2" convertor. You could potentially go from a 2200 now ...to a 4000 stall. Yet if set up correctly by the convertor shop cruising with the 9 1/2" in town and on the highway would act similiar to the stock 2200. It may even slip less. That is what makes it tight. It IS the best of both. The 2200 does nothing better other then selling it for iron cause it's heavy or if it's for a truck.

Now that you have a "real" performance convertor buy a cam with some duration move your power peak higher and make some horsepower!

I don't buy picking a convertor 300rpm above the torque peak. I would get as high of rpm flash as I could but not slip with your 3.55s cruising. Best to call a company and get the convertor built for your car...not order one and hope you like it.

Some shops can make a 10" work...but in most case the 9 1/2 is hard to beat. Also fits a 500hp engine very well.

A example of a loose convertor is in our drag car. It's a 9" turbo action 5000 stall. The car barely moves until 4000. It cooks the oil on the street because it slips so bad.
Ive done a bit of reading and watching some videos on stall convertor explanation on impeller, turbine, and stator. Forgive my lack of knowledge, but to put it into laymans terms, your stall basically is a clutch that by fluid pressure disengages the engine to let it build rpms up before it takes over the work load to take off?
So a higher stall means the engine has to climb to higher rpms before it engages?
Is that a good example?
 
It's a bit more complicated then that in how it multiplies the torque. The tight and loose aspect some translate as just the stall speed. That isn't what I am referring to.... 2 convertors can have the same stall speed...but one set up tight...the other loose.
The torque multiplication is discussed briefly here:
 
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