Help with big cube Small Block.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Originally Posted by Little Mouse
Ratflinger this new 195 eliminator head that they say will flow 300 CFM
at .600 valve lift will it have the heat crossover he wants??
Thats enough airflow to support a lot of HP.
at .600 valve lift will it have the heat crossover he wants??
Thats enough airflow to support a lot of HP.
But an average intake looses from 15 to 25% of the flow so taking 20% as average you are down from 300 to 240 cfm
.257 x 240 x8 = a potential of 493 horse.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Originally Posted by alnukem
I should have said "heat riser". It helps your engine warm up on cold starts by heating your intake, after that, I understand it hurts performance by making the fuel warmer & less dense of charge.....one of the trade-offs. And, yes, the AFR 195's are the biggest heads that have this feature.
Are you running headers or cast manifolds with a heat riser? Do you know what a 195 degree thermistat is?
Thread Starter
Racer
Joined: Jun 2006
Posts: 407
Likes: 11
From: Freedom Pa
Sorry, I am running headers & a 180 degree thermostat right now. I have a friend that built a 355 with the Edelbrock "E-Tec" heads & he says his runs like crap until it's warm, he says in cooler weather, like 10 minutes. Hope that helps. Thanks
Melting Slicks
Joined: Jun 2002
Posts: 2,843
Likes: 99
From: Orrtanna Pa.
Originally Posted by Edzred72
You will get many opinions on this, so you'll have to decide what you want out of your motor. Idel quality...RPM range...street only...street/strip....etc. These factors will determine your component choices.
If your sold on AFR 195's, wait for the new Eliminator series to come out. Acording to AFR, they flow as well as or close to the current Race 210's but you'll sacrifice some high end HP.
The 195's will give good fuel velocity, low end torque & streetability, but you'll loose some top end HP. Optimum head size for a street driven traffic jam 406ci is around 200cc. A high lift (500-550) lower durration (230*-240* @ .050) hydraulic roller cam will also give you great streetability and make pleanty of power in the "street" RPM range. (5500-6000) If you plan on spinning the motor @ + 6000RPM and want all top end power (not practical for the street in my opinion) then a larger head (210cc) size & cam will be needed for optimum power. Your rear gearing, trans, & head size will also dictate your cam choice. Also...I have a 406 with 6" rods, and a standard base circle cam has pleanty of rod clearance.
Opinions will vary....this is just mine.
Good luck with your choice
Eddie
If your sold on AFR 195's, wait for the new Eliminator series to come out. Acording to AFR, they flow as well as or close to the current Race 210's but you'll sacrifice some high end HP.
The 195's will give good fuel velocity, low end torque & streetability, but you'll loose some top end HP. Optimum head size for a street driven traffic jam 406ci is around 200cc. A high lift (500-550) lower durration (230*-240* @ .050) hydraulic roller cam will also give you great streetability and make pleanty of power in the "street" RPM range. (5500-6000) If you plan on spinning the motor @ + 6000RPM and want all top end power (not practical for the street in my opinion) then a larger head (210cc) size & cam will be needed for optimum power. Your rear gearing, trans, & head size will also dictate your cam choice. Also...I have a 406 with 6" rods, and a standard base circle cam has pleanty of rod clearance.
Opinions will vary....this is just mine.
Good luck with your choice
Eddie
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Headers make the cross over not really functional like how it was intended with a heat riser flapper valve that actually forces all the exhaust from one bank through in the bottom of the intake manifold.
So headers and a cross over ends up with some screwed up reversion problems. For that matter very few "Performance" intakes even have a cross over. So it would not matter if the heads did anyway
Most hot rod carbs don't even have a choke like my demon carbs. So they don't have all the nice things like a fast idle cam for starting and warming up.
What i do use is 192 or 195 degree thermistats to get the motor up and toasting warm as fast as possible. I fire up my motors and hold them about 2500 rpm for about 20 seconds and do a couple of petal pumps before dropping the car in gear like when I had my automatic. then you use the throttle and brake to keep the car going out to the street them it's good to go even below freezing.
These big cast iron motown or dart block have alot of metal in them and HP = heat. Cooling is what your going to have to be figuring out during the summer
So headers and a cross over ends up with some screwed up reversion problems. For that matter very few "Performance" intakes even have a cross over. So it would not matter if the heads did anyway
Most hot rod carbs don't even have a choke like my demon carbs. So they don't have all the nice things like a fast idle cam for starting and warming up.
What i do use is 192 or 195 degree thermistats to get the motor up and toasting warm as fast as possible. I fire up my motors and hold them about 2500 rpm for about 20 seconds and do a couple of petal pumps before dropping the car in gear like when I had my automatic. then you use the throttle and brake to keep the car going out to the street them it's good to go even below freezing.
These big cast iron motown or dart block have alot of metal in them and HP = heat. Cooling is what your going to have to be figuring out during the summer
Intermediate
Joined: Aug 2006
Posts: 31
Likes: 0
From: Lynn Ma.
Originally Posted by alnukem
Yes, I'm starting to lean that way. I will probably do the "Little M" block & run the 4 1/8" pistons because I can probably sell my stock 400 block for $400-$500 & have a couple of rebuilds left in Dart block. I am sticking to the new AFR 195's because I want the heat crossovers in the heads. I know I'll take abuse here because nobody runs them but I want something I can run in cool weather without warming it up forever. Do the solid roller cams have a "wider" rpm range of power or is that just my mistaken impression? Thanks again.
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Thread Starter
Racer
Joined: Jun 2006
Posts: 407
Likes: 11
From: Freedom Pa
Sorry for bringing a dead thread back to life after a decade, but I finally finished my build & in the sake of providing information for people searching for results, I am providing them, as there wasn't much info when I was looking.
Basic Build;
4.125" Dart SHP Block with 350 Mains
AFR 195 Eliminator Competition 75cc Heads with heat crossover
Callies Compstar 3.875" Crank
Scat 6" Pro Mod Rods with ARP 2000 bolts
530/530 @ 230/238 with a 112 lobe Hydraulic Roller(It was actually spec'd for a 396 SBC)
Weiand Stealth Dual Plane that was Exude-a-Honed to match the Ports
Barry Grant 650 CFM Mechanical Secondary Carb
Moroso Stroker Pan
Not a lot of Machining of the Pan rails with these rods.
On the Engine Dyno, the results are
560 Peak HP @ 5900
583 Peak Torque @ 4500
Ought to be a good street Engine, which is what I was going for. I know the Cam is too small, but it was paid for! Thanks!
Basic Build;
4.125" Dart SHP Block with 350 Mains
AFR 195 Eliminator Competition 75cc Heads with heat crossover
Callies Compstar 3.875" Crank
Scat 6" Pro Mod Rods with ARP 2000 bolts
530/530 @ 230/238 with a 112 lobe Hydraulic Roller(It was actually spec'd for a 396 SBC)
Weiand Stealth Dual Plane that was Exude-a-Honed to match the Ports
Barry Grant 650 CFM Mechanical Secondary Carb
Moroso Stroker Pan
Not a lot of Machining of the Pan rails with these rods.
On the Engine Dyno, the results are
560 Peak HP @ 5900
583 Peak Torque @ 4500
Ought to be a good street Engine, which is what I was going for. I know the Cam is too small, but it was paid for! Thanks!
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
Sorry for bringing a dead thread back to life after a decade, but I finally finished my build & in the sake of providing information for people searching for results, I am providing them, as there wasn't much info when I was looking.
Basic Build;
4.125" Dart SHP Block with 350 Mains
AFR 195 Eliminator Competition 75cc Heads with heat crossover
Callies Compstar 3.875" Crank
Scat 6" Pro Mod Rods with ARP 2000 bolts
530/530 @ 230/238 with a 112 lobe Hydraulic Roller(It was actually spec'd for a 396 SBC)
Weiand Stealth Dual Plane that was Exude-a-Honed to match the Ports
Barry Grant 650 CFM Mechanical Secondary Carb
Moroso Stroker Pan
Not a lot of Machining of the Pan rails with these rods.
On the Engine Dyno, the results are
560 Peak HP @ 5900
583 Peak Torque @ 4500
Ought to be a good street Engine, which is what I was going for. I know the Cam is too small, but it was paid for! Thanks!
Basic Build;
4.125" Dart SHP Block with 350 Mains
AFR 195 Eliminator Competition 75cc Heads with heat crossover
Callies Compstar 3.875" Crank
Scat 6" Pro Mod Rods with ARP 2000 bolts
530/530 @ 230/238 with a 112 lobe Hydraulic Roller(It was actually spec'd for a 396 SBC)
Weiand Stealth Dual Plane that was Exude-a-Honed to match the Ports
Barry Grant 650 CFM Mechanical Secondary Carb
Moroso Stroker Pan
Not a lot of Machining of the Pan rails with these rods.
On the Engine Dyno, the results are
560 Peak HP @ 5900
583 Peak Torque @ 4500
Ought to be a good street Engine, which is what I was going for. I know the Cam is too small, but it was paid for! Thanks!
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
I had a 427 before this with a much milder hydr. cam and dual plane RPM manifold. Put 485 ft-lbs to the rear wheels at about 4000 rpm. Blast to drive. I have gone a little to far on this build and spent way too much money. School is still out regarding street manners as they day after I got her back on the road I had to leave on a 4 week business trip. First impression on local roads when I drove it to storage was certainly no more responsive in the lower RPM range than my 427.