Hi everyone, just wondering if anyone is or has used the Brodix IK180 heads? Are they good? Bad? Looking to put on my SBC, would like to stay with a 70cc head. Any input would be great.
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Hi everyone, just wondering if anyone is or has used the Brodix IK180 heads? Are they good? Bad? Looking to put on my SBC, would like to stay with a 70cc head. Any input would be great.
You have to be careful when comparing heads because you are not, in most cases, told the flow bench protocol that was used to flow the heads. Did the mfg use a 4.00" intake pipe or a 4.060" intake pipe or a 4.125" intake pipe or what? A bigger pipe will allow the heads to flow a higher number. Did the mfg use undercut valve stems or not? Undercut stems will allow the heads to flow a higher number. What depression was used to flow them? The accepted standard is 28" of water on a manometer, but you have no idea if they don't tell you in their literature, although you can call their tech line. Was an exhaust pipe used? A short pipe will allow more flow, rather than no pipe at all. And so on and so on.
If you don't have a lot of time to compare the entire flow regimen of all the heads that you want to look at, or if it is confusing, then concentrate on only one valve lift, 0.400". This is a quick and simple way to compare heads.
A rough rule of thumb is that you would use the cubic inches of the motor and multiply times 0.5 to get the intake runner size for the heads. 355 cubic inches would work well with a ~180cc intake runner head, for instance. A 400 cubic inch motor could use a 200cc intake runner to advantage. A 327 might run well with a ~165cc intake runner.
For a 355 Chevy, I would not be interested in any cylinder head that would not flow at least 200 CFM on the exhaust side, at some point in the valve lift and I like to see 260/270 on the intake side. Now, you can get 200 exhaust on most any manufacturers cylinder head, but not with smaller runners such as 180/185cc intake runners or even 190cc's. A 355 needs the smaller runners to keep velocity up in order to pack the cylinders and make horsepower. Larger runners (200, 210, 220, 230 etc.) will flow 200, but the velocity suffers and the motor may actually slow down from the less dense packing of the cylinders. I see that Dean already knows this because he's looking for 180cc heads for a 355, but I'm expounding on the info for the benefit of others reading this who may not understand that when it comes to cylinder heads, bigger is not necessarily better. Matter of fact, if I wanted a daily driver to haul grandma back and forth to bingo that would operate from idle to maybe 4000 rpm's, I would choose an even smaller intake runner, something like 165cc or 170cc, for brute off-idle torque to pull a numerically-low rear gear and generate fuel economy using a stock or very mild aftermarket cam. Combination, combination, combination.
Brodix IK180
0.200" 138/112
0.300" 188/149
0.400" 234/167
0.500" 243/175
0.600" 245/178
Brodix 1021002, Brodix Small Block Chevy IK Series Aluminum Cylinder Heads | Brodix
Pro-Filer 23 degree 185
0.200" 135 110
0.300" 201 145
0.400" 245 180
0.500" 265 206
0.600" 270 213
SBC 23 Degree Cylinder Heads
Under $1100 fully assembled, ready to bolt on
Available in 64, 70 and 72cc chambers
Airflow Research 180
0.200" 138 110
0.300" 198 158
0.400" 240 190
0.500" 260 207
AFR - Airflow Research 0919, AFR Small Block Chevy 180cc Eliminator Street Aluminum Cylinder Heads | AFR - Airflow Research
No 70cc combustion chamber examples are available from AFR in this runner size, only 65 and 75
With either the Pro-Filer or the AFR heads, 10.0:1 static compression ratio, Edelbrock Performer RPM intake manifold #7101 or Weiand #8150, a 220-225 @0.050" cam, 750 carb, 1 5/8" long tube headers, this motor would easily produce 400 hp and 400 ft/lbs of torque. Actually, I would rather use the Edelbrock #7104 and a Quadrajet, but that's just me.
Dean, before you choose or purchase ANY parts, please allow me to school you on squish/quench if you don't know about them. Setting the squish/quench properly will make or break a motor and usually involves cutting the block decks to a new block deck height when using aluminum heads. Iron heads will work fine with steel shim gaskets to effect a tight squish/quench, but aluminum heads need some compliance in the head gasket, so a thicker composition gasket is used. When you combine the stock piston deck height of ~0.025" with a, for instance, Fel-Pro 1003 gasket with a compressed thickness of 0.041", you end up with a squish/quench measurement of ~0.066", which is too thick to offer a tight squish/quench to control detonation on pump gas.
What we would do is to measure the "stack" of parts to be used, then cut the block decks to that figure (called "zero decking" the motor) and use the thickness of the composition gasket for our squish/quench figure. For instance, if you used a piston that has a compression height of 1.560", a rod length of 5.700" and add in the radius of the 350 stroke (1.740"), we find a stack height of 9.000" with a block deck height of ~9.025". This is the blueprint dimension that was used at the factory when the 350 was built and leaves the piston down in the bore by ~0.025" with the piston at top dead center. When combined with the steel shim head gasket thickness of 0.020", this puts the squish/quench at ~0.045", just on the high side of what us hot rodders like at 0.035" to 0.045". With the piston crown flush with the block decks with the piston at top dead center and 0.041" composition gasket thickness, the squish/quench is 0.041", which will work nicely to prevent detonation on pump gas.
As the piston approaches top dead center, the close proximity of the crown to the underside of the cylinder head will "squish" or "jet" the mixture out of that area, toward the spark plug, creating turbulence that will bust up pockets of lean and rich mixture in the chamber, homogenizing the mix for a more complete burn and maximum power, as well as preventing detonation on fuel quality that might be less than what the motor wants. The "quench" part of squish/quench is the transfer of heat from the piston crown to the underside of the cylinder head so that the cooling system can carry the heat to the radiator. The closer we get the piston crown to the underside of the head, the better the quench and the more heat extracted from the piston crown.
Some fellows run into a problem when they begin choosing pistons. As I stated, the design compression height (wrist pin centerline to the crown of the piston) of a 350 is 1.560". Some piston manufacturers also make a piston with a reduced compression height to allow cutting of the block decks to bring the block to flat to prevent blowing a head gasket due to a wavy surface on the block. If a fellow isn't careful, he can choose these ~1.540" pistons and add another 0.020" to the piston deck height, which of course widens the squish/quench by 0.020", not a particularly good thing. There are a few piston manufacturers who make 350 piston with a little taller than stock compression height. Keith Black, for instance, manufactures their 350 hypereutectic pistons at 1.561"and I have seen some others that produce pistons with a 0.006" to 0.007" compression height over stock. The taller the piston, the less you have to cut from the block decks to effect a tight squish.
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Thank you Techinspector. I was looking at these heads mostly do to the 70 cc they offer. that would put my SCR at 9:5-1 and dynamic at 7:8-1. I was going to use a .039 head gasket as my block is decked to .005 I think that will be ok for the street. I am just wondering about flow of the heads I don't know much about flow numbers. I did see the AFR heads had higher numbers and there 75cc heads would bring my SCR to 9:0-1 aprox. I am using a 270 /278 @50 219/228 519/530 cam from Lunati. Edelbrock performer manifold and a holly 650. Block is bored .030.
Thank you for all the info gives me a lot to think about before I screw something up..
Hi Techinspector, thank you for all the information, i had posted you back but for some reason it still has not shown..
My block is decked piston to deck is .005 i was going to use a .039 gasket.
After reading your post i am looking into the pro filer heads, 72 cc, that should put me at around 9.5:1 SCR abd 7.8:1 DCR..Will the 185cc be a little too much for me? 350 bored .040 over.
thank you again I was a little confused with the Quench so let me see if i got it now..
piston to deck height .005 + head gasket .039 = .044 that should be ok ? Need to stay within .035 & .045 right?
Yep, 0.044" squish/quench will work fine for use with pump gas Dean, although 9.5:1 SCR and 7.8:1 DCR are very conservative numbers for use with aluminum heads.
What's your piston crown configuration or piston part number, head gasket part number and cam part number that you will use? I'd like to figure the SCR and DCR just to make sure for you, if you don't mind. You have several thousand dollars at stake and I'd hate to see you leave power on the table that could be picked up easily at no additional cost using the 70cc heads instead of the 72's and maybe a little different cam. The 185cc intake runners will work great with your 357 cubic inch motor.
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Hi Tech, this is what i have so far.
350 bored .040
Flat top pistons 4 valve +5.00
piston to deck height .005
Lunati 270/278 Hydraulic roller, @50 219/227 515/530
Head gasket .036 thick-- 4.165 bore
Edelbrock performer intake
street demon 625
Was thinking to keep around 9.5:1 for my cam size, and to keep header heat down a little.
Hi Tech, this is what i have so far.
350 bored .040
Flat top pistons 4 valve +5.00
piston to deck height .005
Lunati 270/278 Hydraulic roller, @50 219/227 515/530
Head gasket .036 thick-- 4.165 bore
Edelbrock performer intake
street demon 625
Was thinking to keep around 9.5:1 for my cam size, and to keep header heat down a little.
Dean says he cannot post on the forum, so sent me the following visitor message....
Hi Tech, For some reason i can't post, I PM the administrator to see whats up Regarding my thread on the Brodix IK heads. this is what i have so far.
350 bored .040
Flat top pistons 4 valve +5.00
piston to deck height .005
Lunati 270/278 Hydraulic roller, @50 219/227 515/530
Head gasket .036 thick-- 4.165 bore
Edelbrock performer intake
street demon 625
Was thinking to keep around 9.5:1 for my cam size, and to keep header heat down a little.
I sent him this reply....
At 9.49:1 SCR with 72cc heads, I get 8.345:1 DCR on the Keith Black calculator. Using the 70cc heads, I get 9.69:1 SCR and 8.518:1 DCR, perfect for pump gas using the tight squish that you have engineered into the motor. I strongly urge you to use the 70cc heads.
Let me add some info that you will want to write down and keep for later....
Cam number Lunati 20560721. With the cam installed straight up, neither advanced nor retarded, intake opens 3.5 degrees BTDC, intake closes 35.5 degrees ABDC, exhaust opens 42.5 degrees BBDC, exhaust closes 4.5 degrees ATDC.......
Intake centerline 106 degrees, exhaust centerline 118 degrees, lobe separation angle 112 degrees.
Cam will want a 2500 stall converter, which is perfectly streetable. This will be a great motor, congratulations on your choices.
The motor will want more intake manifold, a high-rise, dual-plane such as the Edelbrock Performer RPM 7101 or the Weiand 8150 Stealth. You can also find this design used, for a little less money, on craigslist, ebay, racing junk, etc. under Holley 300-36 and Weiand 8016. I advise against using the Edelbrock 7501 RPM Air Gap due to driveability issues in colder climes.
Use a 14" x 4" air filter assembly to allow the motor to breathe.
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Dean, looks like Tech has got some good numbers for you. I would like to chip in an item - I am running an air gap manifold here in the southwest. It is fine after it warms up but is such a slobbering beast until it does. Winter of course makes it worse but even in 80 degree weather it takes a few moments. I think you are located in New York and I highly recommend that you use a performer rpm manifold instead. I have read the difference in horsepower is very small and trust me on this, the difference in everyday manners is huge.
Tech, I have a craigslist 383 which I have taken apart and examined. In my opinion the short block was done by one shop and top end added by someone who just ordered from summit by phone and was given different advice than I would expect. I have sold the summit vortec heads, intake, and summit carb and want to put a good long block together. Object is to street drive, coast to coast, have the most usable torque curve that is huge and flat as a board, and be able to jump on Junior and his new muscle car when desired. The motor will be backed by a bowtie overdrive built 200r, 2500 stall, 3.70 rear gears, 31 inch tires, car weight is 3900,, aerodynamics of a brick . I would like for you to take a shot at recommendations for me.
4.03 bore
3.75 stroke
Ross forged pistons -12cc
6.0 rods
pistons are even with deck - zero
I would like to use the pro-filer heads - 185 or 195 what chamber size?
head gasket .041
performer rpm manifold
780cc Holley 3310 with vacuum secondaries.
Retro fit what roller cam?
Premium gas - mile high altitude for home base
Thanks, I am trying to figure this out before getting too far.
Not certain why, he might be attempting to add a link to his post, for now have him unclick all of the checkmarks under "additional options" and see if that works.Quote:
Originally Posted by techinspector1
Bill S.
You know, hot rodding is fun....until you add an overdrive transmission....and vary the elevation between 5000' and sea level.Quote:
Originally Posted by Scooting
That's what the factory engineers have to do every time they design a new vehicle, but they have mega-computers to aid them in their choices.
The best I have to work with is some basic math and a modicum of common sense, but I'll do what I can to contribute to the project.
The first thing that must be considered is the gears in relation to cam timing. Your 3.70 rear gear with a 0.67 OD transmission gear and a 31" tire is the same as using a 3.20 rear gear, 0.67 trans gear and 27" tire, so the cam will have to be pretty short to work with that at cruise speed (65 mph @1750 rpm's). I have encountered many fellows who failed to take that into consideration, using a cam that has an operating range of 2500-6000 for instance, when they actually need a cam that has a low operating rpm of ~1500-1600 up to a high range of ~5000. Question is, how do you drive around Henry Hotrod with a short cam? The obvious answer is to use a turbocharger or a blower. Before we go any farther, are you up for that?
The other variable is elevation. If you jet the carb for running good at 5000', the motor will go real lean at sea level, with a very real possibility of holing some pistons. If you jet it for running good at sea level, it will be hog-fat at 5000'. The obvious answer is programmable electronic fuel injection with O2 sensors in the header collectors and using a cam with a 114-116 lobe separation angle, like the OEM's do. Again, are you up for that?
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Real world is fun, huh?
Your questions, on a blower, yes. High interest in a M122 Magunson adaption.
On fuel injection, cost plus a strong history to loving carbs slows that desire down.
However, let's talk and see what can be done. Can I get the compression low enough for a blower with the pistons/zero deck?
Nothing is set in stone including my likes/dislikes and am open for education. Have at it.
Not trying to hijack, but I remember a sign at one of the real "service stations" (the kind with mechanics on duty...) back in the early '60's as we drove the road approaching Pike's Peak in Colorado, "Get Your Carburetor Adjusted Here". We were from south Missouri, elevation about 1000' ASL driving at about 6000'ASL and getting ready to be pushing 14,000'. I remember that I couldn't tell the car was running at idle at the top, as it was only turning about 250rpm, and pressing on the gas got a sloooooow ramp in rpm's, zero "snap" to the throttle. I wondered at the time how many people paid a few bucks for smaller jets to drive in the mountains, then wondered why their car ran like crap when they got back home.... We didn't stop, but I expect the mechanic told his customers to stop back in before they headed home, and he'd re-tune them back to flatland specs using the jets he removed a few days before....for another few bucks, of course.Quote:
Originally Posted by techinspector1
Not a hijack at all Roger, I would welcome any and all comments from you other fellows. The more minds we put toward the problem, the better chance we will have of working out a solution.
As of now, I would be thinkin' Pro-Filer 195 heads with 72cc chambers and a Fel-Pro 1003 head gasket for a 9.41:1 SCR. Blower Drive Service says you can run 4 lbs of boost into the motor on pump gas at 9.5:1, so that would be your boost limit, unless you used a good water/alcohol injection unit, such as this....
Snow Performance Boost Cooler Stage-2 Water/Methanol Injection Systems 20010 - Free Shipping on Orders Over $99 at Summit Racing
With that unit, you may be able to run up to 7 or 8 lbs, I'm not sure and would have to counsel with Blower Drive Service about that.
Using a blower, you wouldn't need to worry so much about cam timing, you just cam the motor for what operating range you want and let 'er rip.
I wouldn't try to do any of this without EFI, such as the FAST EFI. Read through the support forum here....
Electronic Fuel Injection Help Fuelairspark.com
In the end, it may be cheaper to sell your place and move to the flatlands. I mean, is it really going to be worth the cost and jumping through all the hoops?
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turbocharged diesel to haul it down to lower altitudes-
Jerry, can you explain why a turbocharged diesel (injected, high pressure) is going to be better than a boosted, injected gas engine?Quote:
Originally Posted by jerry clayton
Diesel has no throttle blades--------runs full open and injects amount of fuel to do what throttle pedal is calling for-----
Boosted, injected gas engine-we are just getting into direct injection engines-all previous to now fuel injected engines were just squirting fuel into the airstream at various points in the system-some at throttle plate, some were somewhere into the flow path usually at manifold to head area with others having more exotic angles,etc.
Any way, the power is requested by throttle opening and will vary with pressure altitudes having tremendous effect on amount of oygen in air --------
Which is why the EFI engine operates from absolute pressure, or alternatively measures mass air flow directly (both for boosted engines). Ray can get where he's wanting to be with the boosted & injected gas engine just fine, IMO.Quote:
Originally Posted by jerry clayton
Its been a while since I flew any supercharged airplanes--------but as I remember,on unsupercharged engines you lose an inch of pressure per thosand feet-29.92 is standard sea level number. and IIRC the normal POUNDS of pressure is 14.7?
And for a engine with a supercharger to actually produce any BOOST above normal ambient pressure it would have to be running way above a driveable speed in the mountains.
Now if you were doing one of the NEW GM direct injected engines with a blower that had a pretty high ratio drive, you might be able to tune around it a bit by severely reducing timing probably to a number that was after tdc soas not to get spark knock at the reduced rpms you would be seeing on the road ( or 145 octane avgas which I don't think has been available since mid 60s?)
Ray, like I said above, IMO you can get where you want to be with an EFI engine that includes spark management (timing). Since the Spark and Injection maps are both based on MAP (manifold absolute pressure), with values programmed from 0 to 31"HG and 0 to peak RPM, the spark and mixture will take care of themselves regardless of your throttle position, load and altitude/barometric pressure. Now I'm not going to tell you that it's gonna knock your socks off if you drive up Mount Evans or Pike's Peak, or that you'll turn the same 1/4 mile times everywhere you go, but your mixture will follow the Injection map and your timing will follow the Spark map, all accounting for the swings in barometric pressure you'll see along the way. Like Denny said, it's gonna take some of your "play money" to pull it together, but I think you can get there. Again, just my opinion, and they're like belly buttons.
Tech's giving you some good guidance, and I look forward to more dialog between you two as you work through your questions and try to optimize the approach. Should be interesting.
OK-to get away from basic differances-
You have stated that you are a carb lovin man and also that you have a Holley -
Leave the static compression RATIO where its at because with the higher alt you won't have too much actual in the cylinder pressure. Get some Holley jets down to around the upper 50s or lower 60s up to mid 70s and a gathering of power valves from 3.5 to 8.5. Does your carb have a seconary metering block or is it one of those thin cheapie plates? If its a plate purchase a seconary metering block kit(will include longer bolts) and also make sure your fuel line set up will work with the longer spacing.
For a starting point Jet the carb down about 4 jet sizes (assuming you are savvy enough(in that thin air breathing those over rich exhaust fumes) to use a consistant brand/source of gas) When you get it running with a decent drivability on the primaries( up until seconary opening point) you can then start on the power stuff with different springs in the vacume opening diaphram and the seconary jets
Then when you do go on a trip where you come down to farm level fiels, you can easily change back to jets that are 2 sizes smaller than whats in the carb as shipped (I like #70 for the 3310 carbs pri)
At least with the Holley you don't have to take off the carb and on a chev the distri isn't in the way of the primary bowl bolts.
Since the air is thin up there, use a pretty open aircleaner to let in as much as you can, choose a cam that gives the atmospere time to push in (remember the engine doesn't suck, the atmosphere equalizes the pressure ) and have as free flowing exhaust as you can stand in the car-might need to try 2 or 3 different type mufflers to get rid of drone sound effects.
And since you are at higher alt you can probably run a couple more degrees of timing if you have good fuel as your absolute cylinder pressure will be lower than when you come down out of the hills for a road trip.
And there are now some systems that you can program ignition timing for carbed engines that work real nice and you can mount them remotely( where you can reach them) in the drivr area
I think I need to back out of hi-jacking this thread and at some point start an engine build thread of my own.
I have noted that on many of the engine build questions, respondents wanted to know as much about the current combination as possible, and how the hot rod was to be used. I attempted to give real answers in how i use my rod and feel that perhaps too much information was given. Also a budget request was often desired which I did not do. As it sets, I am retired and living on SS so toy money is hard to come by. I cannot follow Techs advice and purchase heads $1100, blower $2500, Fast fuel injection $!800/$2500, snow water injection $350 and the price of a cam/lifters. Nor can I sell what I have and plug in a turbo diesel engine as noted. I also hope the suggestion to move my home was in jest. I have ran carbs all my life and am aware of their limitations in comparison but also know they will do the job I want very well. My old 40 has lived on both coasts and at 8500" here in New Mexico. Currently It is jetted 3 sizes lower than when in Baltimore/DC area and in the mid Florida area. With the current jets I have ran with the Greybeards on trips to the LA roadster show without incident. I am smart enough not to push it to the limits at sea level nor over 9000' passes on the way to Denver. Some of the Greybeards have come from Niagara Falls Canada, Florida, the Carolina's, Florida, Oklahoma, Arizona, and the south coast of Texas. I do not recall an injection on any of their cars. I do have the opinion that I can make a carb work just fine for my driving. I like to take long trips because the fun in the ride is often as good as the destination, taking a day trip up the coast like most do is of little interest to me.
I have not spent my youth driving dragsters or other race cars, I do not have the background of building super high performance engines year after year in a high dollar shop, nor do I have the experience of building hundreds of engines in my lifetime. Those are the professionals to whom my questions were directed. I want to build a better motor but feel I need to back off and perhaps come back with limited questions later. Thanks for attempting to help. Ray
Went back and read most of this concerning Scooting's deal===
I did not intend for anyone to think that I meant for him to put a turbo diesel in the car- I meant haul (trailer queen ) it down with a turbo diesel truck and then drive it at the lower altitudes.
At higher altitudes with the thinner air you need to get more into the cylinder-----that means bigger carb, higher flowing heads/manifold and a carb that has been optimized to get the fuel into the airstream-----now you need to have cam timing that is shorter to stop reversion but with more lift so that when valves are open the mixture flows at the best rate for the absolute pressure available . You need the most open exhaust that you ( or the law ) can stand the noise from- lots of split in the overlap so exhaust gets out of the cylinder before intake opens and then open intake at highest rate toward the best flow numbers. Dist needs to be curved and vacume advance doctored for more control ( those old Ford dual diaphram dist work good)
There is a modern type control ( think Edelbrock sold it for there carb manifold on LS type engines?) where you can program the spark even remotely to drivers position ( left side dash?)
If you are building an engine from scratch for high altitude use consider the rod length ratio to stroke for more optimun piston speed at the top and bottom dc.