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New 347 not running right again...

  • Thread starter Thread starter needforspeed440
  • Start date Start date Jul 25, 2004
N

needforspeed440

New Member
Dec 5, 2003
49
0
0
Jul 25, 2004
#1
  • Jul 25, 2004
  • #1
Ok....lot of mods to this car ill try to mention the ones you need to know. Well we just assembled my 347. The intake was leaking oil cause we didn;t do it right. well i fixed that and my rockers wer tapping a bit so i trie to adjust those. Im not real sure what the problem is but after i started it back up the rockers sounded good and all was good. Now while im driving its not near as responsive or fast and around 4200 rpm it just cuts out almost like its nt getting enough fuel. I al WAS having some fuel problems. my 30lb injectors were dumping way to much fuel at 35lb of pressure so i swapped them out and put the 19lbers back in. The fuel pressure is at 38 running. i have good spark and all but im clueless to why its cutting out. It wasn't doing that before i adjusted them but it ran kinda ruff at lower rpms, now.... it runns real smooth but its slow and cuts out around 4200. ANY ideas would help. What is the proper proceedure to adjust the rockers? (crane roller 1.6)
 
D

Daggar

New Member
Jul 19, 2004
3,902
5
0
Jul 25, 2004
#2
  • Jul 25, 2004
  • #2
I'm assuming you have no power adders and I'm no expert on 347s but... have you checked the air/fuel mixture ratio (across the whole power band)? 19lb injectors for your motor seem a bit light.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Jul 25, 2004
#3
  • Jul 25, 2004
  • #3
First, you need the 30's in, assuming you have a nice typical street 347. Unless you have a fairly wild one, then you need 42's. Anyway, sounds like you may have adjusted the valves a little too tight. Possibly overly tight causing them to float up stairs? A slight 'rocker tick' isnt anything to worry about, but it shouldnt be exxcessive.

Here is the method I use, its different from what most use:

TDC #1 adjust: 1 i/e, 2e, 3e, 4i, 5i, 7e and 8i then rotate the engine to TDC #6 and do : 2i, 3i, 4e, 5e, 6 i/e, 7i and 8e. very simple this way.
 
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