Home 
Home Search search Menu menu Not logged in - Login | Register

 Moderated by: Greg Fletcher
New Topic Reply Printer Friendly
cold air box, PCV  Rating:  Rating
AuthorPost
 Posted: 12-20-2009 09:04 pm
  PM Quote Reply
1st Post
jdenglish
Member
 

Joined: 02-11-2009
Location:  
Posts: 80
Status: 
Offline
Group

Has anyone put together a cold air box to outside air for Dellorto's?

In my Dellorto conversion with K&N filters I was going to rout the crankcase vent to an oil catch can but then into  __________?

What about a PCV valve?

Merry Christmas to all

Back To Top PM Quote Reply  

 Posted: 12-21-2009 02:27 pm
  PM Quote Reply
2nd Post
Brett Gibson JH5 20497
Member
 

Joined: 03-17-2005
Location: Hilton, New York USA
Posts: 798
Status: 
Offline
The GT's and late JH5's used a outside air box, that ran a 3" to 4" hose to the side of the radiator bulk head. US box's mated to Strom's. and EU box's to Dell's. and I think there is a Lotus box that is similiar. I can send you a pict. of my Strom one, or just check some GT engine pictures out there.

Brett 

Back To Top PM Quote Reply

 Posted: 12-21-2009 08:53 pm
  PM Quote Reply
3rd Post
John Finch
Member
 

Joined: 08-01-2005
Location: Minneapolis MN
Posts: 122
Status: 
Offline
You might try
 
Gerry Foley
8503  44th Street West
University Place,  WA  98466-7513

(253) 565-2175
gfoley@kendra.com

Two years ago, the airbox parts sold a la carte,  and each half was $45,  or $90 for a full airbox.   That was just the fiberglass bits.   You cut the holes,  sand,  and add your own filter, gasket and hardware.   I don't know current pricing,  or if he's still selling the parts.
 
You might also try Dave Bean to see if they have any of Gerry's air boxes left.
 
Thanks to T Engle for this info.

Back To Top PM Quote Reply  

 Posted: 12-21-2009 11:15 pm
  PM Quote Reply
4th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
The key to any airbox is to make sure there's room for the velocity stacks you are going to use. Add a minimum of 1" to the length of the stack for smooth air flow. 

Short stacks = more HP, long stacks = more torque. Any stack is better than no stack.

I made a extended fiberglass inner half so the 1 5/8" stacks would fit. The breather hose goes into it through a filter fitting I found at Kragen. The carbon canister tube also just connects to the airbox.

Kurt

Last edited on 12-22-2009 02:20 am by Jensen Healey

Back To Top PM Quote Reply

 Posted: 12-22-2009 07:24 am
  PM Quote Reply
5th Post
James Sohl
Member
 

Joined: 04-24-2006
Location: Chandler, Arizona USA
Posts: 18
Status: 
Offline
The Positive Crankcase Ventilation, pcv, valve goes in-line with the hose connecting the vapor separator to the air box.  The idea is that the pcv valve permits crankcase vapor to flow into the inlet air stream for combustion into less harmful emissions.  The pcv valve will close and block flow upon any overpressure in the air box due to popping, backfiring, etc. thus preventing any source of ignition (flame) from entering the crankcase ventilation plumbing.  Crankcase vapor is flammable, and a significant backfire could, at least in principle, cause a fire. 

Back To Top PM Quote Reply  

 Posted: 12-23-2009 07:31 pm
  PM Quote Reply
6th Post
Greg Fletcher
Administrator


Joined: 03-11-2005
Location: Lake Nacimiento, California USA
Posts: 430
Status: 
Offline
Jensen Healeys did not have a PVC valve, I think that was added much later onto the MK III versions. A preformed hose from the crank case to the air box was all that it came with. I have actually never heard of a fire being started this way, but lots I don't know.

Back To Top PM Quote Reply

 Posted: 12-28-2009 06:31 pm
  PM Quote Reply
7th Post
James Sohl
Member
 

Joined: 04-24-2006
Location: Chandler, Arizona USA
Posts: 18
Status: 
Offline
Happy Holidays!
Greg is correct on both counts.  Jensen Healeys were not fitted with PCV valves in the early years, if ever.  As to the possibility of an oil fire, I have never heard of such an occurrence.  The emission regulators of the time apparently thought it made sense, and the oil fire theory persisted for many years.  In actual practice, the function of the PCV valve is widely adopted and so long as the valve does not stick closed, they generally cause no problems.  Crankcase emissions are far more chemically reactive than exhaust gasses and will react with uv-sunlight in the upper atmosphere to create far more 'brown cloud' than an equal mass of exhaust.

Back To Top PM Quote Reply  

 Posted: 05-03-2011 06:59 pm
  PM Quote Reply
8th Post
sjensen24
Member
 

Joined: 08-05-2005
Location: Brooklyn Park, Minnesota USA
Posts: 78
Status: 
Offline
John, I think you showed me your setup to catch oil from the breather tube a couple of years ago.  Can you send me a photo?

Back To Top PM Quote Reply

 Posted: 05-06-2011 03:12 am
  PM Quote Reply
9th Post
John Finch
Member
 

Joined: 08-01-2005
Location: Minneapolis MN
Posts: 122
Status: 
Offline
Here is a pix showing the bottle and cam breather hose into it. The block breather hose is inserted below the red cam hose. The bottle is a bicycle water bottle with an oil breather filter on top that does a pretty good job of filtering oil out. Bottle is pretty easy to remove to empty. Although it never had more than 1/4" per season. Feel free to stop over and take a look. I'll post another pix too. Hope this helps

John

Attachment: Breather bottle sm.JPG (Downloaded 116 times)

Back To Top PM Quote Reply  

 Posted: 05-06-2011 03:13 am
  PM Quote Reply
10th Post
John Finch
Member
 

Joined: 08-01-2005
Location: Minneapolis MN
Posts: 122
Status: 
Offline
Another less cluttered view.

Attachment: Dellorto Passenger Side.JPG (Downloaded 111 times)

Back To Top PM Quote Reply

Current time is 05:57 am  
> Jensen Healey & Jensen GT Tech > Carburetors > cold air box, PCV Top




UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems