• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Pokageek's Pain thread. 351 stroker (414c.i.) swap PROBLEMS.

  • Thread starter Thread starter Pokageek
  • Start date Start date Aug 19, 2007
Prev
  • 1
  • 2
  • 3
  • 4
  • …
  • 7
Next
First Prev 2 of 7 Next Last

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Aug 24, 2007
#21
  • Aug 24, 2007
  • #21
Thanks BV. I just am hoping my issues can help someone else avoid trouble when they build theirs. That's the goal for me and why I post mainly.
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Aug 25, 2007
#22
  • Aug 25, 2007
  • #22
Ok. Took it too a muffler shop and they basically rebuilt my H-Pipe to fit the Cobra R headers. They seal real nice now! Now that the car is quieter..I can tell I have to adjust the rockers better..Acouple of them sound like a vw beetle, lol.

Next Issue:
When she warms up and on the beltway for a bit, it begins to run rough and really buck below 2k rpm..like it is on 7 cylinders and the check engine lights up. But when I got off the b-way, check engine light turned off again but still runs ruff When I start it up though, for the first few minutes it runs smooth..Any ideas experts?
 

Zero_chance

Founding Member
May 29, 2001
1,244
7
59
Maricopa, AZ
Aug 25, 2007
#23
  • Aug 25, 2007
  • #23
Poka sorry to hear about your troubles. Hope you get that all sorted out. I have a question though. Im starting to accumulate parts for a mild 351 setup that Ill be swapping into my 95 down the road. One of the several things Im still not sure on is can you still use the stock PCM to control the 5.8? Ive heard people on both sides of the fence and I figured Id rather ask someone that has one up and running.. even if it is running a little rough.
 

1slow95

Founding Member
May 16, 2002
1,797
3
48
ohio
Aug 26, 2007
#24
  • Aug 26, 2007
  • #24
Zero_chance said:
Poka sorry to hear about your troubles. Hope you get that all sorted out. I have a question though. Im starting to accumulate parts for a mild 351 setup that Ill be swapping into my 95 down the road. One of the several things Im still not sure on is can you still use the stock PCM to control the 5.8? Ive heard people on both sides of the fence and I figured Id rather ask someone that has one up and running.. even if it is running a little rough.
Click to expand...

You can use the stock computer, but a custom tune is highly recommended. If you choose the right parts, it will run fine on the stock tune. It might be a little rough, but it will run.

My car runs pretty good on the stock tune. It even idles just fine. I drove it for a year like that because I couldn't afford to have it dyno tuned. (My engine went slightly over budget )

The important things you need for it run right are:
MAF calibrated to injector size
GOOD (working) O2 sensors
A milder cam setup, in the 114LSA or higher range. A custom cam is the best way to go.
 

Black95GTS

Active Member
Jan 8, 2004
1,644
3
38
Marlborough, MA
Aug 26, 2007
#25
  • Aug 26, 2007
  • #25
Pokageek said:
Next Issue:
When she warms up and on the beltway for a bit, it begins to run rough and really buck below 2k rpm..like it is on 7 cylinders and the check engine lights up. But when I got off the b-way, check engine light turned off again but still runs ruff When I start it up though, for the first few minutes it runs smooth..Any ideas experts?
Click to expand...

This sounds like you are having troubles when you go from open loop to closed loop in your tune. Your car's pcm runs open loop when you start the car, go wide open throttle, hard acceleration, or the engine is cold.

Oxygen sensors are not in operation.

After the car is warmed up, the O2 sensors come into play affecting the A/F mixture. So I would think your problem is:

1 - Tune related or 2 - Your O2 sensors are malfunctioning.

Adam
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Aug 26, 2007
#26
  • Aug 26, 2007
  • #26
Yes, yo can run on the stock pcm..at least I am and I know Low 5.0 is. But a tune is highly recommended if you do..

Thanks for the input Black95GTS. Kinda sucks cuz my sensors are about a year or so old. I will try the tune first..

[EDIT] (as usual) I forgot to mention that new huge sway bar? WOW!!! Real stiff front end and NO LEAN in turns AND GREAT handling!!! Wow what a difference!! And not that expensive a mod!
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Aug 26, 2007
#27
  • Aug 26, 2007
  • #27
+1 on the tune and computer thing. i have a stock pcm too. for me, it'll be a while before i can say my tune is done, because i want it to idle and cruise like a stocker, but go like a raped ape when i drop the hammer

hey man, post a link to that swaybar, ok?
 

1slow95

Founding Member
May 16, 2002
1,797
3
48
ohio
Aug 26, 2007
#28
  • Aug 26, 2007
  • #28
Pokageek said:
Next Issue:
When she warms up and on the beltway for a bit, it begins to run rough and really buck below 2k rpm..like it is on 7 cylinders and the check engine lights up. But when I got off the b-way, check engine light turned off again but still runs ruff When I start it up though, for the first few minutes it runs smooth..Any ideas experts?
Click to expand...

I agree on the O2 sensors. I would check the codes first tho.
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Aug 26, 2007
#29
  • Aug 26, 2007
  • #29
I ot it from mustangs unlimit. Looks like they don't sell that size anymore. It is a 1 3/8 front swaybar. The largest it looks like is 1 1/4.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Aug 26, 2007
#30
  • Aug 26, 2007
  • #30
Zero_chance said:
Poka sorry to hear about your troubles. Hope you get that all sorted out. I have a question though. Im starting to accumulate parts for a mild 351 setup that Ill be swapping into my 95 down the road. One of the several things Im still not sure on is can you still use the stock PCM to control the 5.8? Ive heard people on both sides of the fence and I figured Id rather ask someone that has one up and running.. even if it is running a little rough.
Click to expand...

The pcm family for 94-95 Stangs consists of 5 different versions of software

One of them is the ZA0 which was used in the Cobra R powered by a 351

As a matter of fact

You could use a Tweecer to upload the ZAO calibration file to your existing
pcm you now are using

Grady
 

nmcgrawj

Advanced Member
Sep 28, 2003
3,651
4
68
Indianapolis, IN
Aug 26, 2007
#31
  • Aug 26, 2007
  • #31
final5-0 said:
The pcm family for 94-95 Stangs consists of 5 different versions of software

One of them is the ZA0 which was used in the Cobra R powered by a 351

As a matter of fact

You could use a Tweecer to upload the ZAO calibration file to your existing
pcm you now are using

Grady
Click to expand...

x2


And for another who has done it, i put a 351 with ported twisted wedge heads, TFS-R intake, and a Ed C. cam in my car and tuned it with a PMS just fine.....

Which means i used the stock GT setup and just modified it...no use of an actual 5.8 program....

I think its so easy with the PMS because our cars are load based (right grady? ) so a 5.8 will just have more load compared to a 302 using the exact same computer.

Anywho, just my experience....
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Aug 26, 2007
#32
  • Aug 26, 2007
  • #32
nmcgrawj said:
x2


And for another who has done it, i put a 351 with ported twisted wedge heads, TFS-R intake, and a Ed C. cam in my car and tuned it with a PMS just fine.....

Which means i used the stock GT setup and just modified it...no use of an actual 5.8 program....

I think its so easy with the PMS because our cars are load based (right grady? ) so a 5.8 will just have more load compared to a 302 using the exact same computer.

Anywho, just my experience....
Click to expand...

You bet

Hey ... this is a great time to point out a basic but important fact

Stock 94-95 Stangs with 302 or 351 .........
They all use the same pcm as far as hardware is concerned
Its only the info in those pcms that is different

So no matter if you use

SCT Pro Racer
Tweecer
PMS
as a self tuning interface
or even
You have a Pro burn you a chip

The same basic objective is sought with each method :Word:

You gotta get the pcm updated
with info that matches the needs of your current combo

Grady
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Aug 27, 2007
#33
  • Aug 27, 2007
  • #33
Next Issue: As you know I did the fox TB conversion but I couldn't justify paying $94 for a new throttle cable. So I bought a used one,..but every time I hit the gas...Sqqqqqueeeeeek! Anybody run into this? I wd40'd it too.
 

nmcgrawj

Advanced Member
Sep 28, 2003
3,651
4
68
Indianapolis, IN
Aug 27, 2007
#34
  • Aug 27, 2007
  • #34
Pokageek said:
Next Issue: As you know I did the fox TB conversion but I couldn't justify paying $94 for a new throttle cable. So I bought a used one,..but every time I hit the gas...Sqqqqqueeeeeek! Anybody run into this? I wd40'd it too.
Click to expand...

I got a used throttle cable for my fox swap too....the throttle cable itself is squeeking? Thats really weird. I assume you're finding the squeek by pushing the gas with the car off? Maybe soak the whole cable in something...i dunno maybe some soap? Maybe it'll coat it enough if u cant spray into the cable housing.

Or maybe its just dirty inside so a good underwater wash in a lot of soap might help
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Aug 27, 2007
#35
  • Aug 27, 2007
  • #35
Maybe it is the "ball " end. I will re-oil it. Yes, with the car off too.

Ok,I reoiled that and it seems that the throttle cable is no longer squeaking...I tightened up all the vacuum lines and throttlebody. SO now I am thinking it is POSSIBLY my belt? It SOUNDS like a metal squeak BUT it might be a belt that is slightly loose deceiving me...
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Sep 7, 2007
#36
  • Sep 7, 2007
  • #36
Still chasing down the squeak. The car drove fine today for a short run though b/c my belt keeps coming off as it is 1/2 inch too long at 85..if I go to 84, I cant even get it to go on.. Plus it APPEARS that my tensioner pulley is a little off or something...weird.

Solve: I (think) best way around this is to put the dummy pulleys back on (a/c elimintae and smog delete...that I sold lol. That may correct the issue..

The 36# tune seems ok, and new 02's and plugs but on start up, I still need to floor it sometimes to crank over - not sure why. I will need more driving and testing b4 I feel it is 100%.

Anyone elses's header wrap smoke alot BTW?
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Sep 7, 2007
#37
  • Sep 7, 2007
  • #37
Pokageek said:
The 36# tune seems ok, and new 02's and plugs but on start up, I still need to floor it sometimes to crank over - not sure why.
Click to expand...

If you are still using an unmodified pcm
or
Unless your start up fuel table has been optimized

It thinks you got 19lb inj's
but
In reality you are suppling almost twice the fuel when you crank it

Grady
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Sep 7, 2007
#38
  • Sep 7, 2007
  • #38
final5-0 said:
If you are still using an unmodified pcm
or
Unless your start up fuel table has been optimized

It thinks you got 19lb inj's
but
In reality you are suppling almost twice the fuel when you crank it

Grady
Click to expand...


Ahh, ok, so there is a "startup" table too?? Thanks x10 for the info Grady! I think the startup table is either programmed for 24# or 19# . Kauffman's just programmed the 36# tune thru te mail for me to get it running well enough to drive it up to them in the next few weeks..I bet they did not tune that particular table.

Also I FOUND THE SQUEEK! It is coming DIRECTLY out of the air filter! .. so I wonder if I put the vacuum tube back into the intake tube then maybe it will go away! But I will have to close of the OTHER valve cover's breather if Hisson was right.

It was kind of funny...I drove into the garage and the car pooped the belt out on the driveway... it is like the idler pully is the one that's off..although I did get a new alternator with a slightly larger pulley..Maybe changing back to the old pulleys will work..frustrating..
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Sep 7, 2007
#39
  • Sep 7, 2007
  • #39
Pokageek said:
Ahh, ok, so there is a "startup" table too?? Thanks x10 for the info Grady! I think the startup table is either programmed for 24# or 19# . Kauffman's just programmed the 36# tune thru te mail for me to get it running well enough to drive it up to them in the next few weeks..I bet they did not tune that particular table.
Click to expand...

I'm sure they can take care of that issue for you
but
Don't forget to tell them about it

In the meantime ... as you talked about ......
you can crank it with the skinny pedal on the floor
and
that will kill the fuel during the cranking period

It just takes a while to get things all sorted out

Grady
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Sep 7, 2007
#40
  • Sep 7, 2007
  • #40
Once again Grady is the MAN! Ok, latest solves to issues:

#1 I would also like to mention that I changed my "pcv system" over to a closed system again and will check it in the morn. This means I capped the one valve cover and basically went back to the 94/95 setup with a tube going from one breather to the intake tract just behind the MAF. I will report back on results. Hopefully this gets rid of the SKREEEEK!! coming from the cone air filter.

#2 I figured out that my was of "rigging" the tensioner pulley was kinda dumb.. I was putting a washer behind it that did NOT allow it to center properly on the spindle that the bearing wraps around.. So to correct that yet still move the tensioner out a hair (it seems to stop spitting the belt out when I do that) , I fabricated a nylon washer to fit AROUND the spindle so that the pulley can still center AND mobe properly. I will report back tomorrow..

Once again, thanks to everyone here for listening and I hope my build helps someone else one day.
 
Prev
  • 1
  • 2
  • 3
  • 4
  • …
  • 7
Next
First Prev 2 of 7 Next Last
You must log in or register to reply here.

Similar threads

R
What's it Worth? 1997 Cobra, a ton of mods and restoration
  • riored97snake
  • Jun 18, 2026
  • What is it Worth?!?!?
Replies
2
Views
152
What is it Worth?!?!? Jun 21, 2026
riored97snake
R
SN95 Desktop 363 Engine Combination - Looking for input
  • WhiteCobra95
  • Sep 8, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
11
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 6, 2025
Habu135
6
Hey all,I’m putting together a 302 for my 1968 Mustang and wanted to post the combo + some questions to make sure I’m not missing crucial
  • 68_Disgustang
  • Feb 22, 2026
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
4
Views
851
1965 - 1973 Classic Mustangs -General/Talk- Jun 20, 2026
gray owl
G
M
Progress Thread mnky99 2001 V6 evap core, ac compressor, heater core replacement
  • mnky99
  • Sep 5, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
1
Views
496
1996 - 2004 SN95 Mustang -General/Talk- Sep 5, 2025
mnky99
M
For Sale 3-owner 1987 Mustang GT, $18K obro, Lancaster CA
  • Bill Cool
  • Oct 6, 2024
  • Fox Body Mustangs For Sale (1979-93)
Replies
4
Views
2K
Fox Body Mustangs For Sale (1979-93) Oct 13, 2024
nickyb
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?