Moparchat - Home of MOPAR enthusiasts worldwide!



Go Back   Moparchat - Home of MOPAR enthusiasts worldwide! > Technical Forums > Performance Talk

Click here to search for Mopar cars and parts for sale.


Reply
 
Thread Tools Display Modes
  #1  
Old 01-15-2002, 02:04 AM
Larry S. Larry S. is offline
Inactive User
 
Join Date: Aug 1999
Location: Deming NM USA
Posts: 516
Question Block the heat crossover passage?

I'm putting a Wieand dual four barrel intake on the hemi, and I want to block the heat crossover passage. It's not necessary here in the desert, and I want to keep the intake charge as cool as possible. Anybody have any suggestions on how to do this? So far, the only thing I can figure would be to put a thin metal shim under the intake gasket to cover the exhaust gas port in the head. The only intake gaskets available for the 392 are composition type. How thick would the sheetmetal have to be to keep from burning out, and would I have to thin the gasket where the sheetmetal would be to get it to seal right? I hope someone has had some experience doing this, these early hemi gaskets aren't cheap!
Reply With Quote
  #2  
Old 01-15-2002, 02:18 AM
rumblefish360's Avatar
rumblefish360 rumblefish360 is offline
Moparchat Bronze member
 
Join Date: May 2000
Location: C
Age: 57
Posts: 11,120
Default

Dont thin the gasket. Just put the metal block under it. Hold there with a dab of sealent. How thick? Good question. Anybody know how thick they are for the small block?
Reply With Quote
  #3  
Old 01-15-2002, 09:55 AM
jelsr jelsr is offline
Inactive User
 
Join Date: Dec 2001
Location: Dighton, Kansas
Age: 84
Posts: 1,253
Default

.022-.025 in stainless would be perfect. The stainless is not absolutely neccessary, the valley pan for BB's can come already blocked and they are just mild steel.
Reply With Quote
  #4  
Old 01-24-2002, 12:34 PM
Rug_Trucker Rug_Trucker is offline
Inactive User
 
Join Date: Aug 2000
Location: Near Nashville TN
Posts: 774
Default

Some people use epoxy to fill the passage. On my 360 I run the MP stainless squares, thick gaskets are the key or you could end up with an internal vac leak. You can use aluminum off a beer can but it will eventually burn through. Or a Cambells can, still will eventually burn.
Reply With Quote
  #5  
Old 01-24-2002, 02:41 PM
JJessico JJessico is offline
Inactive User
 
Join Date: Sep 2001
Location: Columbia, SC
Posts: 75
Default

At what temperature do you need a heatcross-over that works? I live in Duluth, MN up by the tip of Lake Superior so i'm sorta worried that if I get a new aluminium intake and block the crossover I'll be screwed. The thing is I only drive my Car in the spring, summer, and early fall. I do not drive it in the winter. The thing is sometimes summer and sprng and fall are a tid bit chilly up here. What would you guys recommend for a temperature that it needs to be above to have a blocked crossover.

Thanks,
Jason
Reply With Quote
  #6  
Old 01-24-2002, 04:21 PM
Rug_Trucker Rug_Trucker is offline
Inactive User
 
Join Date: Aug 2000
Location: Near Nashville TN
Posts: 774
Default

My 360 is driven year round it has been driven in 7* this year. That is about as cold as it gets here. Being a small block it gets hot oil splashing on it and hot coolant in it.
Reply With Quote
  #7  
Old 01-26-2002, 09:56 AM
turbotim23 turbotim23 is offline
Inactive User
 
Join Date: Jan 2001
Location: wyoming,Mi.USA
Posts: 136
Default Block the heat crossover passage?

I bought stainless crossover plates from D.C.Saved looking for right size stainless.I heard that in cold temps blocking the crossover causes fuel to wash the oil off cylinder walls,Causing cylinder wear[during warm up].I was still going to do it but was gong to take them out when it starts getting cooler. I thought of welding crossover openings,milling flat then drill and tap for fittings top of intake into crossover passage each side.This offers many possibilites.You could purge nitrous system through crossover then out to blow down onto radiator. Or pump water through crossover into a iced fuel cooler can. Good luck Tim
Reply With Quote
  #8  
Old 01-26-2002, 04:42 PM
Frans Veldman's Avatar
Frans Veldman Frans Veldman is offline
Inactive User
 
Join Date: Apr 2001
Location: Netherlands
Age: 59
Posts: 59
Default

For my 318 I bought a Mopar performance gasket, and it came with two stainless steel sheets for blocking off the heat passage. I found out that these metal pieces were the same thickness as the gasket, so I cut out some of the gasket and glued the metal pieces into it. It worked great.

About the temperature, I drive my 318 mainly on propane and that doesn't need a heated intake at all. One time I ran out of propane and switched over to gas, temperature was just above freezing, but after 70 miles or so the lifters became very noisy as if there was no oil pressure. Some people told me that most likely the fuel didn't vaporize very well, washed down the cylinder walls and diluted the oil so much that it bled too fast out of the lifters.

If I had to drive on gas, I would for sure open up the passage again. The gain is minimal and the damage caused by badly vaporized fuel could be severe.

I wonder how much the air is heated on its rush through the intake. The amount of air rushing through the intake is tremendous (CID * RPM/2) so it doesn't get time to be heated much. I think the main function of the heat passage is to prevent the fuel from condensating, which is a very bad thing and actually cost you more power than you would gain by the temperature drop.

As I said, I drive on propane, and that doesn't condensate at all so that's why I blocked off the passage.

Frans
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Blocking Heat Crossover??? moparmotorman Performance Talk 9 07-01-2003 04:58 AM
Heat Crossover? BakedMopar Performance Talk 7 04-20-2003 08:11 AM
Blocking the heat crossover dave571 Performance Talk 21 11-28-2002 08:41 AM
Heat crossover jimbo7074 Performance Talk 3 03-25-2002 01:38 PM
Good Idea or bad.Heat passage blocking Marvin S Performance Talk 4 08-03-2001 08:58 PM




All times are GMT -4. The time now is 05:14 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
. . . . .