[joesgt281]

Hey guys.....well the old motor is about shot and I've got a new mill on the engine stand.
I'm wondering what I may need to address immediately to get this thing to run.

I'm going from:
- built low compression motor
- stock 97 cams
- shorty headers
- SVO heads and intake
- vortech 12# S-trim
- 36# injectors
- 77 mm MAF
- 4R70W trans

to:
- built low compression motor
- Crower Stage 2 blower cams
- long tube headers
- Fox Lake Stage 2 heads
- Bullitt Intake
- vortech 12# S-trim
- 60# injectors
- 90 mm MAF
- 4R70W trans

I know I have to re-adjust my maf curve and change the injector size.
Anything else come to mind?

Thanks!

[m0l0]

Out the basics you have already mentioned, the obvious ones , if you change your TB , the ISC Air Flow
if you are too deep into the perfect tune , i would change your injector timming to match your new cams, i havent tried EA on a DOHC engine , but i think it also works on a DOHC engine with different cams,mmm your HEGO Delay since you are switching to longtube headers, mm your are switching intakes so to avoid lean tip ins also the intake volume could also be changed, also since you are changing mayor stuff on the engine i would start the tune all the way since the basics: little timming , dial AFR, then slowly star adding up timming, other than that i think you will be fine

[joesgt281]

I'd heard that the long tubes could mess things up and sounds like the HEGO delay is where I need to focus.
What exactly would I need to change on that?

Also, not clear on changing the injector timing to match the cams. What is required there?

Thanks!

[m0l0]

I'd heard that the long tubes could mess things up and sounds like the HEGO delay is where I need to focus.
What exactly would I need to change on that?

Also, not clear on changing the injector timing to match the cams. What is required there?

Thanks!

There was a Excel Spreadsheet where you input the collector diameter , length, i don’t remember all the inputs you needed, I will search for it i must have it somewhere , it was probably an approximate of where to start with the HEGO delay , I don’t know how precise it is but should get the work done.

On the cam things, if you have EA already you can take a look on the Cam Specs tab, you should input all the cam data and will have to make a couple of runs, how ever i would leave in your case, when you have all the other mayor changes dialed in. and then work all the way up to the "perfection" of the tune.

I must say that on this Injector Timing there is a lot of discussion that if it actually does something that helps.
In my past experience it worked on the idle and a little driving smoothness of the engine, so if you start using it, you could make your own conclusions, as i stated before this was on a OHV engine, but i haven’t tried on a DOHC engine, so it can make a huge difference, if there is someone more with past experience on this matter please chime in and share your experience.

[joesgt281]

Good stuff, I appreciate it.
Not sure if it makes a difference, but I have an SOHC rather than a DOHC or OHV.
I don't have EA yet for the cam stuff, but I have one more reason to go for it now.......thanks!