Re: newbie blues
[Re: 71scamp440]
#449753
08/25/09 05:45 PM
08/25/09 05:45 PM
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Joined: Oct 2004
Posts: 601 Clintwood VA
johnedod
mopar
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mopar
Joined: Oct 2004
Posts: 601
Clintwood VA
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That area in the center of the head above the gasket is supposed to be open. The cross over is the small hole. No problem they are all like that.
Johnedod 68 Road Runner 71 Road Runner 78 Power Wagon
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Re: newbie blues
[Re: 71scamp440]
#449757
08/25/09 05:55 PM
08/25/09 05:55 PM
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Joined: Jan 2004
Posts: 27,347 Today? Who Knows?
1_WILD_RT
Management Trainee
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Management Trainee
Joined: Jan 2004
Posts: 27,347
Today? Who Knows?
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Quote:
what purpose does that hole serve?
It separates the hot exhuast crossover passage from areas where oil flows, oil in direct contact with ezcess heat causes the oil to cook and form hard deposits known as coke deposits...
Oh BTW lots of guys use a gasket designed to block the head to the intake... It greatly reduces the tendancy of the fuel to boil out of the carb fuel bowls... Newer fuels are designed for fuel injected vehicles & don't react well to excess heat without being pressurized like fuel injection does...
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Re: newbie blues
[Re: johnedod]
#449759
08/25/09 05:58 PM
08/25/09 05:58 PM
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Joined: Oct 2004
Posts: 601 Clintwood VA
johnedod
mopar
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mopar
Joined: Oct 2004
Posts: 601
Clintwood VA
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Sorry R/T didn't know you had already posted.
Johnedod 68 Road Runner 71 Road Runner 78 Power Wagon
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Re: newbie blues
[Re: Dougsmopars]
#449768
08/25/09 06:29 PM
08/25/09 06:29 PM
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Joined: Jan 2004
Posts: 27,347 Today? Who Knows?
1_WILD_RT
Management Trainee
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Management Trainee
Joined: Jan 2004
Posts: 27,347
Today? Who Knows?
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Quote:
If it's not a full race motor and your just driving the car for fun don't worry about the crossover. Mother Mopar didn't think it was a problem and thousands of them are running around with it open as designed. My GTX has a fairly healthy 440 and mine are not blocked and no problem with fuel boilling.
When Ma Mopar designed these cars/engines fuel was completely different than it is today...
You don't want to block the heat, that's fine, the fuel isn't gonna get any better & in California we already get what you will be getting... But we also have a warmer climate which amplifies the problem.. Personally I see the intake being off right now as an opportunity to improve the future starting/driving of thew engine...
BTW I edited my above post with the pt #
Oh and as far as the engine temp with the crossover blocked, it actually runs cooler..
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Re: newbie blues
[Re: wingman]
#449772
08/25/09 09:37 PM
08/25/09 09:37 PM
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Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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get the valley pan gasket w the holes blocked. Trust us on this one.
live every 24 hour block of time like it's your last day on earth
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Re: newbie blues
[Re: 71scamp440]
#449773
08/25/09 09:47 PM
08/25/09 09:47 PM
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Joined: Jan 2003
Posts: 9,436 Blair County,PA
62maxwgn
master
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master
Joined: Jan 2003
Posts: 9,436
Blair County,PA
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Quote:
im having a case of the newbie blues. im putting a set of 915 heads on a 400 block. all was going well until i got to the intake. my gaskets dont fit properly. i think its leaving the heat cross over open? do i need a special intake with these heads. both the 400 intake and a 440 intake fit fine with the exception of this hole being wide open. what do i need to do to solve this problem?
Either I'm reading your post wrong but the 440 intake will not fit the 400 block.If you are refering to gaskets,then you're ok.
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Re: newbie blues
[Re: 1_WILD_RT]
#449776
08/26/09 06:59 AM
08/26/09 06:59 AM
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Joined: Jul 2007
Posts: 531 Virginia
JimG
mopar
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mopar
Joined: Jul 2007
Posts: 531
Virginia
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Quote:
Yeah, Felpro makes one with it blocked, I'll see if I can find the number... FWIW some guys don't like blocking the heat, in the old days I didn't either, but the fuel has gotten to the point you've gotta do something..
Felpro #1214
http://www.summitracing.com/parts/FPP-1214/
Have you guys had problems with the "blocked" portion of the gasket burning through?
I never tried the FelPro, but I had a Mr. Gasket burn through once. Now, I use .030" stainless steel shim stock in that area, even if the gasket is already blocked. I had read that only stainless steel will survive in that environment, and the burned through gasket seemed to confirm that.
Perhaps I'm needlessly going overboard; I'd like to hear your experiences.
Thanks!
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Re: newbie blues
[Re: Mr.Yuck]
#449781
08/26/09 09:21 AM
08/26/09 09:21 AM
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Joined: Oct 2003
Posts: 21,345 Marysville, O-H-I-O
70Cuda383
Too Many Posts
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Too Many Posts
Joined: Oct 2003
Posts: 21,345
Marysville, O-H-I-O
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nothing much to add here from me! block it, leave it open...it's your choice. to help you decide--some theory behind it! the reason it was there originally, was because these cars were driven year round...or at least, engineered to drive year round. that's why the carbs have chokes, the exhaust has those little flapper valves and the intakes are heated with exhaust gasses. the passenger side "flapper valve" thingy was shut when the engine was cold. this blocked the exhaust (not entirely though) and made it go through that port, through the intake, and out the driver side exhaust. this was to heat up the intake, and to help the fuel atomize, or stay atomized as it passed through the intake, as well as simply warm it up to make it easier to burn. as the engine warmed up, your choke would open up from engine heat, and that flapper valve would also open up, allowing the exhaust an easier shot at going out instead of through the cross over (but, some will still go through it even at full operating temps) today's cars are usually NOT driven year round, and some semblance of performance is desired from them. for maximum performance you want a free flowing exhaust, free flowing intake, and a COLD air/fuel mix coming into the engine because colder air is more dense, and has more O2 to burn, making more power...thats why Cold Air Intakes are so popular...even if they only provide you with 2 or 3 hp. (they all advertise 15-20 though! some do, some dont!) so...ask yourself, is this a summer only vehicle? or will it be used year round? mine is a summer only toy, so my cross over is blocked, and the exhaust is free from any "flapper valve" (sorry, I don't know what it was actually called), and my Carb does NOT have a choke. It really doesn't like to start when it's 45 degrees or less outside, and even when it's 85, I gotta sit there and hold it at 1500-2000 rpms for a few minutes until it warms up enough to idle without stalling. but once warmed up, it idles great, and hot starts are NEVER a problem. now you have the information to make the decision on your own, instead of just counting up how many people have said "I have mine open" compared to how many said "I have mine closed"
**Photobucket sucks**
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Re: newbie blues
[Re: 70Cuda383]
#449782
08/26/09 03:00 PM
08/26/09 03:00 PM
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Joined: Jan 2008
Posts: 417 jamestown, ny
71scamp440
OP
Hinged
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OP
Hinged
Joined: Jan 2008
Posts: 417
jamestown, ny
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Quote:
nothing much to add here from me!
block it, leave it open...it's your choice.
to help you decide--some theory behind it! the reason it was there originally, was because these cars were driven year round...or at least, engineered to drive year round. that's why the carbs have chokes, the exhaust has those little flapper valves and the intakes are heated with exhaust gasses. the passenger side "flapper valve" thingy was shut when the engine was cold. this blocked the exhaust (not entirely though) and made it go through that port, through the intake, and out the driver side exhaust. this was to heat up the intake, and to help the fuel atomize, or stay atomized as it passed through the intake, as well as simply warm it up to make it easier to burn. as the engine warmed up, your choke would open up from engine heat, and that flapper valve would also open up, allowing the exhaust an easier shot at going out instead of through the cross over (but, some will still go through it even at full operating temps)
today's cars are usually NOT driven year round, and some semblance of performance is desired from them. for maximum performance you want a free flowing exhaust, free flowing intake, and a COLD air/fuel mix coming into the engine because colder air is more dense, and has more O2 to burn, making more power...thats why Cold Air Intakes are so popular...even if they only provide you with 2 or 3 hp. (they all advertise 15-20 though! some do, some dont!)
so...ask yourself, is this a summer only vehicle? or will it be used year round?
mine is a summer only toy, so my cross over is blocked, and the exhaust is free from any "flapper valve" (sorry, I don't know what it was actually called), and my Carb does NOT have a choke. It really doesn't like to start when it's 45 degrees or less outside, and even when it's 85, I gotta sit there and hold it at 1500-2000 rpms for a few minutes until it warms up enough to idle without stalling.
but once warmed up, it idles great, and hot starts are NEVER a problem.
now you have the information to make the decision on your own, instead of just counting up how many people have said "I have mine open" compared to how many said "I have mine closed"
thanks 70 cuda. i think im going to leave mine open for now. in N.Y where i live 45 degrees can happen in the middle of summer, so i better leave it open. but then again im gonna run a manual choke so it doesnt matter either way i guess. 6 of one and a half dozen of another.
71 scamp
big block with 915 heads
727 trans
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Re: newbie blues
[Re: 71scamp440]
#449784
08/26/09 05:18 PM
08/26/09 05:18 PM
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Joined: Oct 2003
Posts: 21,345 Marysville, O-H-I-O
70Cuda383
Too Many Posts
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Too Many Posts
Joined: Oct 2003
Posts: 21,345
Marysville, O-H-I-O
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Quote:
thanks 70 cuda. i think im going to leave mine open for now. in N.Y where i live 45 degrees can happen in the middle of summer, so i better leave it open. but then again im gonna run a manual choke so it doesnt matter either way i guess. 6 of one and a half dozen of another.
yea...not sure it matters...the choke WILL make cold starts easier. but, that is countered by the air flow restriction the choke horn makes.
no choke means more airflow into the carb... but if you're running the heat cross over, then it's going to be hot air!
at one point, I had an edelbrock carb with electric choke on my truck, with the heat cross over blocked, and it would fire off almost immediately, sit on the high idle cam for 15-20 seconds, blip the throttle, and it would idle like it had been running for 30 minutes!
I would consider a choke with blocked off cross over before I would consider no choke with it open.
once it's warmed up, you don't really need the heat cross over, and a cold start...there's no heat in there to help out anyway! that's where the choke helps out!
**Photobucket sucks**
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