GT-40p Head/Explorer Intake Discussion

I have a VERY similar combo, i'm running a 73mm C&L with 24#'s, 3.55 gears and all that stuff you listed (cobra intake instead of explorer )

Anyways, teh low end torque is DEFINATELY there!!
It'll easily roast them all the way through 2nd gear (on 7inch wide turbines, lol)

I wouldn't woory about the low end. I have been driving my car around for a week now and I have a little MORE low end and ALOT more top end. I do have 4.10's though, but either way, I felt an increase everywhere. I just went to the track with my 315 nitto drag radials and I spun quite a bit through second, hurting my time. I installed my cam straight up too. If you are worried about low end, advance the cam like 2 degrees.

Also, as far as the MAF, if you are keeping the stock injectors, I wouldn't even get one. It may cause you to need a tune and it's alot of money for not that much power.

matthiasj said:

What size MAF should i get to bring a few ponys to the new setup? I'm keeping 19#ers with a 190 fuel pump and an adjustable fuel pressure regularor.

Matt

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Your goal for the combo will require more fuel than 19's can support and more air flow than a typical 19lb caled maf can meter.

Just go for 24's & matching caled maf when needed so you don't waste money. Until then, the stock inj's & maf will be fine.

I'd go for the 255lph intank fuel pump over the 190lph.

When you do need a maf, I'd go for a ProM 77 or 80.

Later
Grady

It will run real lean when I had 19 # injectors on and went to the dyno it was at 19.0 to one on the air fuel ratio I went to 30# and it was running at a nice 13.0 to one.

Get an FPR and the 19's will be perfect for your initial goals.

You can use an AFPR and 19# up to 44psi fuel pressure - if you have to run more fuel pressure to get the right A/F ratio, step up to 24# or 30# with the matching MAF.

matthiasj said:

What size MAF should i get to bring a few ponys to the new setup? I'm keeping 19#ers with a 190 fuel pump and an adjustable fuel pressure regularor.

Click to expand...

FWIW...my last dyno was with an 93 Cobra upper to see the gain from the previous Summer....I run Thumpers/19 cam...all the base mods for heads...anyway I opted to stay with 19s to see what gives..I run a 190 also....
I was told by alot of people that my AFR would tell me if the 19s were being maxxed.....did 3 pulls and never touched a thing...AF ratio was on the money From my last dyno....timing was 14 with 38 lbs from the prior dyno....Guy said don't touch nothing....
I lost 15 lbs tq with the upper from a stock Tmoss lower, but gained 12 ponies with the intake and 1.6 RRs...
I run a long Pro-77..
263 RWHP 295 TQ was where it came in...
I have a Accufab 75 and 24s waiting to go on..If I feel game this year I'll throw em on to see the dif...My 77 is cal'd for 19s so I gotta get a chip to add em though...

RIO5.0 said:

FWIW...my last dyno was with an 93 Cobra upper to see the gain from the previous Summer....I run Thumpers/19 cam...all the base mods for heads...anyway I opted to stay with 19s to see what gives..I run a 190 also....
I was told by alot of people that my AFR would tell me if the 19s were being maxxed.....did 3 pulls and never touched a thing...AF ratio was on the money From my last dyno....timing was 14 with 38 lbs from the prior dyno....Guy said don't touch nothing....
I lost 15 lbs tq with the upper from a stock Tmoss lower, but gained 12 ponies with the intake and 1.6 RRs...
I run a long Pro-77..
263 RWHP 295 TQ was where it came in...
I have a Accufab 75 and 24s waiting to go on..If I feel game this year I'll throw em on to see the dif...My 77 is cal'd for 19s so I gotta get a chip to add em though...

Click to expand...

I don't doubt anything you have said and you've got the data to show your 19's are getting the job done but I wanted to just throw in my .02 cents worth as they say.

I do think you are at the limit of those 19's or your close to it.

Based on inj duty cycles of data logs some of the other self tuning guys have told me about, I have come to think the limit for 19' is about at the 265 to 275rwhp range at stock fuel pressure. Seen a few threads with dyno results of lean ratios to give me that train of thought as well.

If you up the pressure you can push em a bit farther to be sure.

Another thing to consider when looking at inj size is those formulas quote fwhp and us Stangers always think in rwhp. There is a difference!

Each combo is different and some reach the limit of the stock 19's sooner than others. The ability or efficiency of the combos parts to move air is a big factor and the amount of error in the maf's transfer curve is another factor that will cause probs also, which again, is different in each combo.

You don't wanna be too lean and unfortunately, the condition that it happens at is max load and max rpm

IMHO, this is an aera where its better to be safe than sorry.

Later
Grady