302 Problems when Cold

non vehicle specific forum for tuning all other EEC-IV

302 Problems when Cold

Unread postby gamh44 » Tue May 15, 2018 4:28 am

All

Firstly what a great resource here at efidynotune. So much information! I’ve read lots but there’s a lot more to go. Such a steep learning curve. The most tuning I've done previously is adjusting the float level on a 350 Holley!

I have a Cobra replica with a 302HO engine that ran really well right out of the box. Now upgraded with Trickflow 170s and cam with a Massflo (now Pro-M I believe) intake and MAF, 24lb injectors (too small?). J3 chip to suit by a local club member who has done a few of these very successfully. No idea what was done in the tune.

Since the H-C-I upgrade it has always been a bit rough on idle and it has also backfired a bit under heavy acceleration when cold. There has also been a bit of bucking under about 2000rpm, especially on deceleration.

I am now thinking of heading down the QH path so as to identify and sort out the niggling issues.

Of course, there are 1000 questions to be asked. Here are the two deal breakers:

1. Will the A9L2 (GUFB) tune work fine with the 8LD (GUFA) ECU? It appears so but I just want to be sure.
2. Can I really expect to smooth out these cold idle and running issues. Local tuner said cold start issues were to be expected. I would just like the car to start and drive with reasonable manners. At the moment I have to nurse it a little for the first few miles.

I have been chasing my tail a bit trying to identify what might be causing the issues - checking for vacuum leaks, leads, timing and even rocker adjustment.

The best improvement so far has come from checking the fuel pressure. Not sure how but it was down around 36psi (vac off). I have now brought it back up to 40psi (actually just a little over) and that improved things considerably.

The dizzy was also one tooth off so that has also been rectified. Seems to have made a difference to drivability but hard to tell. Still can't understand how the dizzy can be a tooth off but it is set right now!

I can't think of anything else mechanical that it might be - hence considering looking at the tune.

Lots more to share but I will leave it there for now.

Any thoughts appreciated


Geof
gamh44
General Poster
 
Posts: 3
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip (on way). TunerPro RT.

Re: 302 Problems when Cold

Unread postby decipha » Tue May 15, 2018 4:45 am

1- yes
2- yes, he is ignorant

dizzy off throws off injector timing

just by your "tuners" statement that its to be expected is a clear indication of his incompetence. I would expect no less with his tuning abilities. Anyone that understand the ecu knows any setup can be dialed in so long as no mechanical issues exist and the engine components are well suited for what your trying to achieve.
User avatar
decipha
Tooner
 
Posts: 14328
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Ponthieux
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce

Re: 302 Problems when Cold

Unread postby gamh44 » Tue May 15, 2018 6:06 am

Cool, thanks for the reply!

Is there anything else mechanical to consider before looking into the tune?

If not, it looks like QH will be the next step.

Cheers
gamh44
General Poster
 
Posts: 3
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip (on way). TunerPro RT.

Re: 302 Problems when Cold

Unread postby decipha » Tue May 15, 2018 6:19 am

the qh is a diagnostics tool too so it would give you more info on what mechanical isnt up to par
User avatar
decipha
Tooner
 
Posts: 14328
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Ponthieux
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce

Re: 302 Problems when Cold

Unread postby gamh44 » Tue May 15, 2018 2:26 pm

That's exactly what I wanted to hear. Thanks. Off to get myself a QH.
gamh44
General Poster
 
Posts: 3
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip (on way). TunerPro RT.

Re: 302 Problems when Cold

Unread postby decipha » Tue May 15, 2018 2:35 pm

User avatar
decipha
Tooner
 
Posts: 14328
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Ponthieux
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce


Return to EEC-IV Tuning

Who is online

Users browsing this forum: No registered users and 2 guests