My engine rebuild thread!
- Thread starter Daryl
- Start date
ttocs
Post Whore
my next big purchase is a nice 347.
OP
OP
So here’s the final dyno numbers. All said and done I gained 70 ft lbs torque and 40hp. Needless to say I am severely disappointed given all the time, work and money I’ve put into it to arrive at 267max torque and 202 max hp. But that’s how Cali-fucking-Fornia with the FOUR cat requirement on this car fucks you I guess.
The dyno guys knew I was disappointed and informed me of an off-road H-pipe that, if I can get one in CA, is a direct swap R&R for the cat section of my choked down, gagging exhaust.
The dyno guys knew I was disappointed and informed me of an off-road H-pipe that, if I can get one in CA, is a direct swap R&R for the cat section of my choked down, gagging exhaust.
Man, I’m not sure the cats are going to get you 100hp. Those are stock kind of hp numbers. I’m upset for you.
ttocs
Post Whore
thats no joke I had mine put on a dyno during a dyno day when it was bone stock and it was 187/250 I thought. That was with stock cats, stock air filter, stock everything. Its been a while what was the build list again? Is it running reliably now at least?
Wmac
Active Member
Daryl, can you post the dyno sheet?
And if I can ask, what fuel pump, what maf, injectors and throttle body?
And if I can ask, what fuel pump, what maf, injectors and throttle body?
ttocs
Post Whore
something isn't right imo but I am not an engine expert by any means, still working on my youtube cert. Where is black?
joemomma
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Yeah that seems really low. Again, I'm no expert, but I play one on the interwebs from time to time. With a 347 with that H/C/I you should be pushing over 300w. The heads may be holding you back a little, but not 100hp. I agree with the others, something seems amiss.
How does it feel driving? Is there another shop around you could book some dyno time on? Maybe their dyno is whack.
How does it feel driving? Is there another shop around you could book some dyno time on? Maybe their dyno is whack.
joe65
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wow, yeah something's not right. just the heads alone should wake up a basic 302 but a 347. tune is not right. Sorry but the cats don't choke a na that much. I've gone from the stock 4 cats on a mach 1 to an x with 2 cats and it wasn't a noticeable difference except sound.
TrickVert
Active Member
The stock cats actually flow well*, so unless your cats are cooked, that's not likely your problem. I agree that there's something else going on. My HCI 302 with GT40P's made 272 RWHP and 302 lb-ft TQ before the Vortech was installed.
*From THIS FORUM ARTICLE - Super Ford, May 1996:
"Before proceeding with our exhaust modifications, we wanted to try a set of off-raod pipes with the stock headers and mufflers. Off-road pipes, which bolt in place of the factory catalytic converters, are not street legal, but many 5.0 Mustang owners bolt them on for the drag strip or road course. So after our Phase 1 bolt-ons and before discarding the stock headers and mufflers for Phase 2, we slipped in a set of off-road pipes from Pacesetter. We immediately noticed a more high-performance growl from the stock mufflers. On the Dynojet, the off-road pipes picked up 5.5 horsepower."
*From THIS FORUM ARTICLE - Super Ford, May 1996:
"Before proceeding with our exhaust modifications, we wanted to try a set of off-raod pipes with the stock headers and mufflers. Off-road pipes, which bolt in place of the factory catalytic converters, are not street legal, but many 5.0 Mustang owners bolt them on for the drag strip or road course. So after our Phase 1 bolt-ons and before discarding the stock headers and mufflers for Phase 2, we slipped in a set of off-road pipes from Pacesetter. We immediately noticed a more high-performance growl from the stock mufflers. On the Dynojet, the off-road pipes picked up 5.5 horsepower."
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TrickVert
Active Member
Daryl: I just thought of something - Where do you live (altitude), and were those readings actual or corrected for sea level? Mine were corrected values. Actual here is probably 25% lower.
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ttocs
Post Whore
honestly if the injectors were holding you back the tuner should have been able to see that and then try to sell you the parts. 42 lb would be more than enough but you will need another tune for them 
or a maf that is made to work with them. The maf can work but if we are already suspecting problems I am not sure I would say to go that way.
or a maf that is made to work with them. The maf can work but if we are already suspecting problems I am not sure I would say to go that way.
TrickVert
Active Member
Well... That's not it, then.
TrickVert
Active Member
My N/A combo above was using 24# injectors. According to THIS CHART, 32's should be adequate for yours, but 42# squirters could be tuned in OK as well. Also according to that chart, my 42#-ers should not be enough for me now with ~ 475 HP (corrected) at the motor, but they're no problem. Of course, at sea level, maybe they'd max out. I'll have to remember that. Knowing what I do today, though, I would've gone with 60's.
