Slant *        6        Forum
Home Home Home
The Place to Go for Slant Six Info!
Click here to help support the Slant Six Forum!
It is currently Sun Nov 24, 2024 8:46 am

All times are UTC-08:00




Post new topic  Reply to topic  [ 8 posts ] 
Author Message
PostPosted: Sat May 23, 2009 8:51 pm 
Offline
TBI Slant 6
User avatar

Joined: Tue Sep 18, 2007 12:35 pm
Posts: 156
Location: Blounts Creek, NC
Car Model:
and I am now in a bad mood. The car was running 7.90's last week @ T.N.T and tonight when we unloaded it ran a 9.96 off the trailer? We checked everything we could think of and went back out to a 8.99 on the next pass. We did everything we could thin of and never could get back to that 7.90 range. The car was sluggish off the line and would miss on most every pass. I am at a loss. :evil:

_________________
Image


Top
   
 Post subject:
PostPosted: Mon May 25, 2009 5:43 pm 
Offline
TBI Slant 6
User avatar

Joined: Tue Sep 18, 2007 12:35 pm
Posts: 156
Location: Blounts Creek, NC
Car Model:
Anyone got any suggestions on what may have happened?

_________________
Image


Top
   
 Post subject:
PostPosted: Mon May 25, 2009 5:52 pm 
Offline
Board Sponsor & Moderator
User avatar

Joined: Thu Oct 17, 2002 7:27 pm
Posts: 14485
Location: Park Forest, Illinoisy
Car Model: 68 Valiant
Wet plugs, blown head gasket, bent valve, water in the fuel, list is endless. Just gotta start at the easy stuff and verify what is working and what is not. :shock:

_________________
Official Cookie and Mater Tormentor.


Top
   
 Post subject:
PostPosted: Mon May 25, 2009 6:22 pm 
Offline
TBI Slant 6
User avatar

Joined: Tue Sep 18, 2007 12:35 pm
Posts: 156
Location: Blounts Creek, NC
Car Model:
Thanks slantzilla.

I think I found the culprit. I had a 650 cfm carb on the car during T.N.T. when the car was running 7.90's. The car seemed to be running a little lean so I took the carb off and my brother took it to rejet it and flow it. Well without my knowledge he switched my 650 with his 750 (he has said all along he did not think the 650 was enough) and put the 750 on my car. It appears we over carbed the car. We are going to change the carb back and see if that fixes it. Also we were running the car at about 9 psi on the fuel pressure and I think that was too much also.

_________________
Image


Top
   
 Post subject:
PostPosted: Wed May 27, 2009 7:19 am 
Offline
Board Sponsor & Moderator
User avatar

Joined: Mon Oct 21, 2002 11:08 am
Posts: 16792
Location: Blacksburg, VA
Car Model:
99% of the time, the thing that makes the car not run or run worse is something you changed. This is a very good rule of thumb to keep in mind.

Sounds like you found the culprit.

I would put the 650 back on with the exact jets and setup as before, and jet up or down from there, at the track. 650 is enough carb for about any Slant anyone can build.

Lou

_________________
Home of Slant6-powered fun machines since 1988


Top
   
 Post subject:
PostPosted: Wed May 27, 2009 5:37 pm 
Offline
Board Sponsor & Moderator
User avatar

Joined: Thu Oct 17, 2002 7:27 pm
Posts: 14485
Location: Park Forest, Illinoisy
Car Model: 68 Valiant
Back the fuel pressure down to 5 to 6 psi. Holley needles are supposed to be good at 9 psi, but they will leak through.

A 750 should work IF it's set up and tuned properly.

I'm betting it had high floats and wet a plug. :?

_________________
Official Cookie and Mater Tormentor.


Top
   
 Post subject:
PostPosted: Wed May 27, 2009 6:52 pm 
Offline
TBI Slant 6
User avatar

Joined: Tue Sep 18, 2007 12:35 pm
Posts: 156
Location: Blounts Creek, NC
Car Model:
We adjusted the floats and kept jetting the carb down, we could never get it to not miss.

I have put on a new fuel pressure regulator and have set it at 6 psi. The 650 carb has been rebuilt and is now back on the car. I will be unable to make T-N-T tomorrow, hopefully I will be ready next Thursday.

_________________
Image


Top
   
 Post subject:
PostPosted: Fri Jun 05, 2009 6:05 am 
Offline
TBI Slant 6
User avatar

Joined: Tue Sep 18, 2007 12:35 pm
Posts: 156
Location: Blounts Creek, NC
Car Model:
Went to T.N.T last night and found some of the problems. We rechecked the timing and found that somehow we were about 160 deg. off. Yes you read that correctly. :shock:

So we got the timing fixed and went and made another pass and the car would never turn up on the RPM. Came back in and the spark plugs were white on the tips and the headers were really hot, so we are now running extremely lean. :evil:

_________________
Image


Top
   
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 8 posts ] 

All times are UTC-08:00


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Limited