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Need help after Head and Intake Swap.

  • Thread starter Thread starter NotchAbove
  • Start date Start date Feb 14, 2009
N

NotchAbove

New Member
Jan 24, 2007
29
0
0
Feb 14, 2009
#1
  • Feb 14, 2009
  • #1
I could use some help here. Let me try to lay this out as best I can.

Just finished putting on Ported E7's, Cobra Intake, 30# injectors, C&L MAF, 1.7 Rockers. Install went well I think. I fired her up today and everything seemed pretty good once I set the idle and the timing. Car idle's at 1200 and Timing was at 16*, and Fuel Pressure at 40-42 ish.

Once I went for a ride there is a noticeable issue right away, once you get on it, she bogs down real bad, and if you punch it, it will backfire.

What I did ensure was that the distributor went back correctly, where as when the harmonic is pointed at 0 (TDC) the rotor is pointed to the #1 mark on the cap. I believe that is how it should be.

I'm inclined to lower the FP a touch, but not sure if that will correct it. Perhaps the 30#'s are too much, but I plan on spraying it, and need the injectors.

Any help would be appreciated.
 

SPEEDYLIFSAVR

Founding Member
Sep 18, 2000
666
0
16
FL,89 LX 5.0
Feb 14, 2009
#2
  • Feb 14, 2009
  • #2
place your thumb over the #1 cylinder spark plug hole and make sure you feel air rushing out to make sure your engine was at TDC when re-stabbing your distributor .
 
3

347HO

Member
Jan 13, 2008
462
2
16
Seattle
Feb 14, 2009
#3
  • Feb 14, 2009
  • #3
What did you install that is new to the setup?
If I read your post correctly... heads, intake and rockers are new to the setup?
What year bottom end also?
 

KamiKaziDK

Member
May 16, 2005
555
0
17
Mesa, Az
Feb 15, 2009
#4
  • Feb 15, 2009
  • #4
That seems like a lot of fuel pressure to me, I run 44 psi on stock 19s with my small list of mods below as recomended by MAC, but I wouldn't think that's totally causing your problem. back the timing down to 12* for reliability for now, double check all your vacuum connections and timing, and back down the fuel pressure, see how that works.
 

the pony boy

Founding Member
Apr 19, 2002
358
0
16
10512
Feb 15, 2009
#5
  • Feb 15, 2009
  • #5
double check your timing.do a search on here theres a ton of good how to's.the backfiring leads me to believe that its off a bit and also why such big injectors? phil
 
N

NotchAbove

New Member
Jan 24, 2007
29
0
0
Feb 15, 2009
#6
  • Feb 15, 2009
  • #6
Thanks for the responses guys.

SPEEDYLIFSAVR: Let me try to give some answers. As far as the distributor, I put it back based on the harmonic, which was NOT pulled, so the timing marks on that should be correct as that was not touched. Am I missing something here as far as how it should be working.

347HO: That is correct, also added 30# injectors and a matching C&L Meter, for 30# injectors. Everything else was swapped over. 93 Stock Bottom end.


KamiKaziDK: I agree on the FP and am going to do just what you suggested and back down the timing some and the FP to around 38-39.

the pony boy: The injectors are for when I spray it. I want to be able to use the 125 shot, and figured that with 24#;s I could be getting close to running lean.

Keep the responses coming, I will report on my findings shortly. Thanks guys.
 
3

347HO

Member
Jan 13, 2008
462
2
16
Seattle
Feb 15, 2009
#7
  • Feb 15, 2009
  • #7
Because the heads are new to the setup as well as the rockers, I suggest you check your pushrod length for correct alignment of rocker tips to valve stems.
If pushrods are not the correct length, you will have similar symptoms.
 
N

NotchAbove

New Member
Jan 24, 2007
29
0
0
Feb 15, 2009
#8
  • Feb 15, 2009
  • #8
347HO said:
Because the heads are new to the setup as well as the rockers, I suggest you check your pushrod length for correct alignment of rocker tips to valve stems.
If pushrods are not the correct length, you will have similar symptoms.
Click to expand...

Well they are just ported E7's, and the Rockers are the Crane 1.7's as used on the Cobra. I went through the procedure of tightening them in order.
 
2

2000wjFUH2

New Member
Jun 28, 2007
8
0
0
nc
Feb 16, 2009
#9
  • Feb 16, 2009
  • #9
Did you use an oil windage tray? Upper/lower cobra intake kit doesn't come with it. Bogs down and backfires within intake and increases oil consumption with some white exhaust smoke. Sucks oil up into intake without it. To see if this is your problem, simply check to see if back spark plugs #4/#8 are black with oil especially #8 (closest to firewall driver side). Front ones will be cleaner.
 
N

NotchAbove

New Member
Jan 24, 2007
29
0
0
Feb 16, 2009
#10
  • Feb 16, 2009
  • #10
2000wjFUH2 said:
Did you use an oil windage tray? Upper/lower cobra intake kit doesn't come with it. Bogs down and backfires within intake and increases oil consumption with some white exhaust smoke. Sucks oil up into intake without it. To see if this is your problem, simply check to see if back spark plugs #4/#8 are black with oil especially #8 (closest to firewall driver side). Front ones will be cleaner.
Click to expand...

If your talking about the oil baffle on the lower Ford changed to a much larger one now, it covers the whole back end of the intake.
 
N

NotchAbove

New Member
Jan 24, 2007
29
0
0
Feb 16, 2009
#11
  • Feb 16, 2009
  • #11
Here's an update. I checked the pushrods to ensure they free spun when the valves were closed, and they were still torqued to the correct setting.

I do think the problem is the way I put the distributor in last time. Now it seems to line up better and that makes me think I have the timing retarded. Here are some pics of where I have the distributor put in.

View attachment 270399


View attachment 270400 Here is the position of the rotor, when the Balancer reads TDC like pic above.
 
N

NotchAbove

New Member
Jan 24, 2007
29
0
0
Feb 17, 2009
#12
  • Feb 17, 2009
  • #12
Solved. Timing was retarded big time. I manually turned the distributor until the idle came up, and then figured out what was wrong. I still need to set timing with a light but had to stop for the night.

Thanks all for your help.
 
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