head size
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
head size
having a hard time making up my mind on heads, with a 331 if I were wanting it to run say 2500 to around 5500 or so I would just buy a 180 runner head. But I can care less what it could do below 4000 rpm. so I'm trying to decide if a 200 runner is to big or not with more upper end power in mind. Then its a bit tempting to buy some profiler aluminum heads over the iron darts. But with the 3.25 stroke 64cc chambers force's me into a dome on the piston I don't really want.
If the ports are bigger on a dart heads then advertised I don't want to big a port. I sure don't want a 200 head that's more like 210.
If the ports are bigger on a dart heads then advertised I don't want to big a port. I sure don't want a 200 head that's more like 210.
Last edited by Little Mouse; Mar 23, 2014 at 10:34 AM.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
having a hard time making up my mind on heads, with a 331 if I were wanting it to run say 2500 to around 5500 or so I would just buy a 180 runner head. But I can care less what it could do below 4000 rpm. so I'm trying to decide if a 200 runner is to big or not with more upper end power in mind. Then its a bit tempting to buy some profiler aluminum heads over the iron darts. But with the 3.25 stroke 64cc chambers force's me into a dome on the piston I don't really want.
If the ports are bigger on a dart heads then advertised I don't want to big a port. I sure don't want a 200 head that's more like 210.
If the ports are bigger on a dart heads then advertised I don't want to big a port. I sure don't want a 200 head that's more like 210.
I believe that the restriction is my early intake valve closing and not the intake runner volume.
To get a smaller chamber you could have the head shaved and possibly avoid domed pistons.
Thread Starter
Le Mans Master
Joined: Apr 2006
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I can tell you that my 180 SHP darts that actually are 200cc's run up to 5700 rpm without a hick-up. It will continue to 6000, which I haven't been past, just not as quickly.
I believe that the restriction is my early intake valve closing and not the intake runner volume.
To get a smaller chamber you could have the head shaved and possibly avoid domed pistons.
I believe that the restriction is my early intake valve closing and not the intake runner volume.
To get a smaller chamber you could have the head shaved and possibly avoid domed pistons.
Last edited by Little Mouse; Mar 23, 2014 at 11:41 AM.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
Just checking that is a 4.0" bore and 3.25 stroke correct?
If I run that through this calculator
http://www.jeepstrokers.com/calculator/
I get 10.02:1 CR with a .040 squish, 5cc flat tops and a 61 cc chamber. Are you looking for more than that?
Race Director
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From: Corsicana, Tx
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I'm not sure I follow...you don't care about anything under 4000...but want to shut it down at 5500???
I'm assuming cam choice is going to peak around 5000 or so? That's going to really limit the power potential of the 'lil motor.
Why are folks so afraid to rev stuff??? I've twisted stuff to the moon all my life and have never thrown a rod out of one yet. If the factory put 6500 RPM redline son stuff with wimpy 11/32'nds rods, and the mild valvesprings, stamped rockers etc etc with a warranty, you can rest assured there was a good safety margin built in.
From what you're describing a set of Vortec's could easily handle it. A buddy had a .060 over 327 with 11.0 pistons and a set of iron SR Torquers and it ran pretty hard with a mild solid flat tappet in it. They also make a set with 58cc chambers.
JIM
I'm assuming cam choice is going to peak around 5000 or so? That's going to really limit the power potential of the 'lil motor.
Why are folks so afraid to rev stuff??? I've twisted stuff to the moon all my life and have never thrown a rod out of one yet. If the factory put 6500 RPM redline son stuff with wimpy 11/32'nds rods, and the mild valvesprings, stamped rockers etc etc with a warranty, you can rest assured there was a good safety margin built in.
From what you're describing a set of Vortec's could easily handle it. A buddy had a .060 over 327 with 11.0 pistons and a set of iron SR Torquers and it ran pretty hard with a mild solid flat tappet in it. They also make a set with 58cc chambers.
JIM
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
I'm not sure I follow...you don't care about anything under 4000...but want to shut it down at 5500???
I'm assuming cam choice is going to peak around 5000 or so? That's going to really limit the power potential of the 'lil motor.
Why are folks so afraid to rev stuff??? I've twisted stuff to the moon all my life and have never thrown a rod out of one yet. If the factory put 6500 RPM redline son stuff with wimpy 11/32'nds rods, and the mild valvesprings, stamped rockers etc etc with a warranty, you can rest assured there was a good safety margin built in.
From what you're describing a set of Vortec's could easily handle it. A buddy had a .060 over 327 with 11.0 pistons and a set of iron SR Torquers and it ran pretty hard with a mild solid flat tappet in it. They also make a set with 58cc chambers.
JIM
I'm assuming cam choice is going to peak around 5000 or so? That's going to really limit the power potential of the 'lil motor.
Why are folks so afraid to rev stuff??? I've twisted stuff to the moon all my life and have never thrown a rod out of one yet. If the factory put 6500 RPM redline son stuff with wimpy 11/32'nds rods, and the mild valvesprings, stamped rockers etc etc with a warranty, you can rest assured there was a good safety margin built in.
From what you're describing a set of Vortec's could easily handle it. A buddy had a .060 over 327 with 11.0 pistons and a set of iron SR Torquers and it ran pretty hard with a mild solid flat tappet in it. They also make a set with 58cc chambers.
JIM
No Jim my meaning was if I were to cam the engine like most would want in a power band form say 2500 to less then 6000 rpm with the small engine I would do a 180 size port it would be easy to decide. I don't care if the engine makes 5 hp below 4000 rpm or even 4500 rpm. I want all the power above that to at least 7500 and shift it at around 8000. I like close ratio transmission have never bought a car with a wide ratio SBC or BBC, hate rpm drops. Car will be very light plenty of gearing in the back. I don't need the car as any form of daily driver its just for fun and grins. I want all the power it can make up top. But don't wan't a port so big it slows velocity down even at the higher rpms planned.. About made up my mind to do a edelbrock street tunnel ram with two 660s or 650s, instead of my offy low profile cross ram, copy of the z/28 crossram.
Last edited by Little Mouse; Mar 24, 2014 at 10:13 AM.
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Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Yes I measured. Before I ported they were as big as 198.6cc's for a 180cc head.
Just checking that is a 4.0" bore and 3.25 stroke correct?
If I run that through this calculator
http://www.jeepstrokers.com/calculator/
I get 10.02:1 CR with a .040 squish, 5cc flat tops and a 61 cc chamber. Are you looking for more than that?
Just checking that is a 4.0" bore and 3.25 stroke correct?
If I run that through this calculator
http://www.jeepstrokers.com/calculator/
I get 10.02:1 CR with a .040 squish, 5cc flat tops and a 61 cc chamber. Are you looking for more than that?
Wallace racing calculater.
yes I want more then 10.00 especially if I were to use an aluminum head. Using a 4.040 bore 3.250 stroke 333 cu. standard stuff like 6cc for valve relief 4.100 dia .041 gasket, zero deck and 64 cc head that's common 9.66 comp. with 61 cc head 10.00 with 49 cc dart iron head head 11.69. Originally going to do a 49 cc dart head around 13 to 15 cc dish piston then you end up in the 10.5 to 10.72 range. They make dish pistons in 13 on up to 28cc and many in between.
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
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anybody with a dyno got an opinion for head size on this small upper rpm job. I walked out in the backyard to do some testing looking for my dyno, someone must have stole it. Leaning a bit to a 195/200 head.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
Your engine is about 19% smaller than mine. If you go 19% smaller on the port size, it comes out 182cc. I would say a 180 to 185 port would be right on the money for you.
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I did the tunnel ram thing about 25 years ago. They were made before monster cc head ports existed. I tried both tops. That is the common plenum and the separate 4 barrels.
I bought it with 660 center squirters. I used them for a few years and then went to dual 450 cfm. 450 and separate 4's is the best setup on small ci
I bought it with 660 center squirters. I used them for a few years and then went to dual 450 cfm. 450 and separate 4's is the best setup on small ci
Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
You want to rev to 7-8000RPM you need good flowing heads, I would not hesitate to put on 200cc++. Which ones ? I would put the AFR 180-195cc haven't built a dud yet. You have to match all the components, I have had my 427ci Motown smally up to 8000RPM
What a lot of old timers don't realize was in the parts in the 60-80's were not that good. Today with computers and CNC machine the tolerances are much closer and the parts are far better as long as they aren't from China.
What a lot of old timers don't realize was in the parts in the 60-80's were not that good. Today with computers and CNC machine the tolerances are much closer and the parts are far better as long as they aren't from China.
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
I did the tunnel ram thing about 25 years ago. They were made before monster cc head ports existed. I tried both tops. That is the common plenum and the separate 4 barrels.
I bought it with 660 center squirters. I used them for a few years and then went to dual 450 cfm. 450 and separate 4's is the best setup on small ci
I bought it with 660 center squirters. I used them for a few years and then went to dual 450 cfm. 450 and separate 4's is the best setup on small ci
Last edited by Little Mouse; Mar 24, 2014 at 12:02 PM.
Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I had the 3 speed Hurst "clicker" in one of my first cars a 57 Chev. First to second you just pull it down, then it clicks and you just shove it right back up to where 1st was for 3rd, really cool shifter, fast and you never missed a gear 
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
You want to rev to 7-8000RPM you need good flowing heads, I would not hesitate to put on 200cc++. Which ones ? I would put the AFR 180-195cc haven't built a dud yet. You have to match all the components, I have had my 427ci Motown smally up to 8000RPM
What a lot of old timers don't realize was in the parts in the 60-80's were not that good. Today with computers and CNC machine the tolerances are much closer and the parts are far better as long as they aren't from China.
What a lot of old timers don't realize was in the parts in the 60-80's were not that good. Today with computers and CNC machine the tolerances are much closer and the parts are far better as long as they aren't from China.
Last edited by Little Mouse; Mar 24, 2014 at 12:36 PM.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
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From: Spring Park MN
lol can't do 4 inch stroke 8000 rpm in the factory block would last no time go kabang, Sure don't have the money to buy the right parts to build one that could last. This little puppy go to big on the port it will be noticed. Have to do the Chinese steel hope the American final finishing work is good.
Race Director
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From: Corsicana, Tx
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OK...NOW I've got you. Sorry...misinterpreted the whole thing from what you were thinking.
Now...we're talking a screamer huh?
Start with the Wallace Calculators to get an idea of cross sectional area needed for your RPM plans and cubes.
I witnessed a pump gas 327 a few years ago on the dyno with a set of 200cc heads that received some porting afterwards along with a solid flat tappet. He got it a little over 500 HP up around 6800-6900...and it hung on well to 7500. Cam was in the 260* range. Figure that's over 1.5 HP per cube...or similar to an 800 HP 540. Pretty good for a pump gas deal! Solid roller could have added to that. Or maybe even a good HR....they spin well on small blocks with good lifters.
Chad Spier is doing some neat stuff with SBC heads that turn some RPM. And his prices are decent also.
JIM
Now...we're talking a screamer huh?
Start with the Wallace Calculators to get an idea of cross sectional area needed for your RPM plans and cubes.
I witnessed a pump gas 327 a few years ago on the dyno with a set of 200cc heads that received some porting afterwards along with a solid flat tappet. He got it a little over 500 HP up around 6800-6900...and it hung on well to 7500. Cam was in the 260* range. Figure that's over 1.5 HP per cube...or similar to an 800 HP 540. Pretty good for a pump gas deal! Solid roller could have added to that. Or maybe even a good HR....they spin well on small blocks with good lifters.
Chad Spier is doing some neat stuff with SBC heads that turn some RPM. And his prices are decent also.
JIM
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,403
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it was a weird deal owner of the impala did not drive his own car barely knew which end of screwdriver was me and the guy I had the shop with worked on it and he drove it they were closer friends. I was pulling the balancer off the owner of the car is looking over my left shoulder. after it was out a little ways I say I think the crankshaft is coming out of the block, he gets all excited jim stop jim stop. I just kept turning on the ratchet then started laughing.
the new rods I bought have a 1/10th more narrow pin end then standard rods can use the new x pistons with as little as 2.00 to 2.25 pin length..
Last edited by Little Mouse; Mar 24, 2014 at 09:54 PM.