GT40s.com
MK-I  MK-II  MK-III  MK-IV  GULF  MIRAGE  J-CAR  LOLA
GT40s.com
Home Forum Gallery Support GT40s.com  
Register FAQ Advertisers Search Today's Posts Mark Forums Read

Go Back   GT40s.com > GT40 Technical Forums > GT40 Tech - Engines/Induction/Exhaust


GT40 Tech - Engines/Induction/Exhaust Motors and engine related - right here!

Reply
 
LinkBack Thread Tools Display Modes
Old 3rd March 2011, 04:20 AM   #1 (permalink)
dave hensley
Bronze Supporter
United Kingdom
 
Join Date: Nov 2006
Location: Bristol UK
GT40: tornado
Posts: 12
302 HO engine

need to know which ports cross over on a 302 HO engine as the firing order is differant to normal 302,
my firing order is 1 3 7 2 6 5 4 8 normal is 1 5 4 2 6 3 7 8 can any one help
dave hensley is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 3rd March 2011, 07:41 AM   #2 (permalink)
Big-Foot's Avatar
Big-Foot
Super Moderator
United States
 
Join Date: Jan 2007
Location: Kenyon, MN
GT40: RCR40 - #45
Posts: 5,146
Re: 302 HO engine

Port Crossover?

It's basically only a camshaft change - the ports (on all the manifolds I'm aware of) are arranged the same between the HO and non-HO 302s..

Or are you speaking on header cross over in a 180 degree format?
__________________
Regards - Randy
GT40 RCR40 #45 G50-331-Weber IDAs
My build site:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Big-Foot is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 3rd March 2011, 09:11 AM   #3 (permalink)
YerDugliness's Avatar
YerDugliness
Lifetime Premier Supporter
United States
 
Join Date: Mar 2006
Location: near Houston TX
GT40: 1/24 scale MKII
Posts: 2,053
Re: 302 HO engine

Agreed, Randy...I think Dave is talking about which "ports" cross over when building a "bundle of snakes". I can see firing order being important in that issue, particularly if one is trying to arrange the header tubes so that the exhaust pulses follow a "circular" path as they enter the collector...might be important for exhaust scavenging?

Cheers from Doug!!
__________________
YD,E./PNB

Retired once, back at work, still attempting to age disgracefully
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
YerDugliness is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 3rd March 2011, 01:07 PM   #4 (permalink)
SteveBarker's Avatar
SteveBarker
Silver Supporter
United Kingdom
 
Join Date: Sep 2003
Location: Yorkshire UK
GT40: MDA GT40MkII
Posts: 374
Re: 302 HO engine

Hi Dave

The picture is a bit rough on a bit of card as my car is , but shows the collectors with the number cylinder in the circles the link lines are the sequence.
The right hand set of four run clockwise however the left don't and run in a Z, if I swapped 5&8 they would run anticlockwise. Don't know if it makes any difference!


Steve
Attached Thumbnails
Click image for larger version

Name:	vcm_s_kf_repr_832x624.jpg
Views:	112
Size:	36.5 KB
ID:	51823  
SteveBarker is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 3rd March 2011, 01:17 PM   #5 (permalink)
jac mac's Avatar
jac mac
I Have No Life
New Zealand
 
Join Date: Dec 2005
Location: Gore, NZ
Posts: 3,460
Re: 302 HO engine

Its the two center cyl that crossover on each bank regardless of firing order, but as doug points out you should endeavour to make them fit in each collector in a circular firing order, this require a bit of pre planning to get the most suitable layout. So for:
13726548 its ..1-7-6-4..RHS set and 3-2-5-8...LHS set.
15426378 its ..1-4-6-7..RHS set and 5-2-3-8...LHS set

Now when you look hard at those numbers you find that the circular sequence works for either firing order as the only thing that really changes is the direction of rotation at the collector and that is not an issue .
jac mac is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 4th March 2011, 03:06 AM   #6 (permalink)
dave hensley
Bronze Supporter
United Kingdom
 
Join Date: Nov 2006
Location: Bristol UK
GT40: tornado
Posts: 12
Re: 302 HO engine

Thanks chaps for the info it is a great help

Cheers
Dave
dave hensley is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 4th March 2011, 09:53 AM   #7 (permalink)
dave hensley
Bronze Supporter
United Kingdom
 
Join Date: Nov 2006
Location: Bristol UK
GT40: tornado
Posts: 12
Re: 302 HO engine

Hi Steve
I take it that your engine is also a 302 HO, it seems the crossover is the same on both types if yours is a 302 HO any chance you can send me a photo of your system to dave@hensley.me.uk
Cheers
Dave
dave hensley is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
302 engine mounts simonjrwinter GT40 Tech - Engines/Induction/Exhaust 6 14th May 2008 12:00 PM
302 engine id simonjrwinter GT40 Tech - Engines/Induction/Exhaust 12 25th January 2007 02:48 PM
302 5.0 HO and Audi Transaxle with Adapter on E-bay pasadena-rob The World Market - Share Parts, Sources, and Reviews 5 28th June 2006 12:28 PM
302 engine wanted 5112ja The Garage Sale 2 24th April 2004 07:49 AM
302 Engine For Sale roy snook The Garage Sale 0 13th September 2003 09:46 AM


All times are GMT -4. The time now is 07:30 AM.