234hp AFTER swap, WTF!!

Blev

New Member
Aug 17, 2003
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So. Cal. V-Town
OK....

So I finally got on a Dyno after my headswap (with no tune) and all I can say is :bs: First run was 227.46 and second was 234.06. No TQ numbers because he couldn't get it to read :shrug: my A/F was 12.47 and pretty damn smooth considering I have not been tuned at all with all of my mods.

Bottom line is what the hell went wrong!! Why are my numbers so low? This was done last minute over at a shop that soley works on Vett's. The guy is really cool and is considering getting the software to tune mustang's. I'm at a loss and seriously considering getting G35 or truck. :damnit:
 
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Blev said:
OK....

So I finally got on a Dyno after my headswap (with no tune) and all I can say is :bs: First run was 227.46 and second was 234.06. No TQ numbers because he couldn't get it to read :shrug: my A/F was 12.47 and pretty damn smooth considering I have not been tuned at all with all of my mods.

Bottom line is what the hell went wrong!! Why are my numbers so low? This was done last minute over at a shop that soley works on Vett's. The guy is really cool and is considering getting the software to tune mustang's. I'm at a loss and seriously considering getting G35 or truck. :damnit:

Whoa! A number on a paper doesn't mean anything. First of all, what kind of dyno? Second, how does the car feel? Does it pull like a beast above 4,000RPM? I got 249 at the wheels on mine and my A/F goes from 13.5 at 2500 to 11.5 at 5500. I'm not getting it tuned because with the increase in compression, I might only be able to go 12 or 13* timing and 5-6Hp is not worth $500 for a chip and tune.

Also, what kind of x-pipe. Off-road or cats? Your numbers are about right if you got converters on there.
 
Do you have an auto or a 5 speed. With my auto I dynoed at 234 before a tune after the swap as well. I was so dissapointed because it seemed like everyone else was making numbers around 250-270 RWHP. My AF was right on track and there was no sign of any problems. I guess some cars just respond better to the swap. :shrug:
 
chimchim said:
Whoa! A number on a paper doesn't mean anything. First of all, what kind of dyno? Second, how does the car feel? Does it pull like a beast above 4,000RPM? I got 249 at the wheels on mine and my A/F goes from 13.5 at 2500 to 11.5 at 5500. I'm not getting it tuned because with the increase in compression, I might only be able to go 12 or 13* timing and 5-6Hp is not worth $500 for a chip and tune.

Also, what kind of x-pipe. Off-road or cats? Your numbers are about right if you got converters on there.
Well, it means a bit to me. I was expecting better numbers after everything I have done to my car. I guess I'm just really let down right now.

It was on a Dynojet The car feels stronger in the higher RPM's but I think I would benefit from a tune. I really felt I would be over 250. All that's really left is a tune and more agressive cams. :(

EDIT=I have a catted X
 
NiteRydaGT said:
Do you have an auto or a 5 speed. With my auto I dynoed at 234 before a tune after the swap as well. I was so dissapointed because it seemed like everyone else was making numbers around 250-270 RWHP. My AF was right on track and there was no sign of any problems. I guess some cars just respond better to the swap. :shrug:

I have an Auto as well. I was also seeing those same numbers by everyone else who has done the swap and that's why I was so disapointed.

Gunfighter said:
those #s do seem low. Did you get a new tune after the install?

I have not had a tune period.
 
As asked, do you have cats and is your car auto. If yes to one or both of these, numbers might be OK. If you got a 5-speed and o/r mid-pipe, something is wrong. Just my .02. :shrug:
 
I know seeing those low numbers is dissapointing, I was in your exact situation like I said above, but chimchim is right, it's not all about the numbers. I've outrun plenty of cars that have dyno'd with higher numbers then mine. My car ran (I've put a '01 shortblock in it since) great with the swap. There is a guy on Modular Depot who has a 98 with the swap and an auto. He only put down like 244 RWHP but is running 12's. When I saw that I wasn't so dissapointed.
Get a tune whenever possible, you'll see some power out of it. It might not be 20 rwhp but it'll be something and it will smooth out everything and optimize everything.
 
Yes, it's an Auto and Yes it's a catted pipe. I guess I was just expecting too much. I thought for sure I would be putting down the same numbers if not better then 99+ with the same mods considering I have the bump in compression. That's also on my of to do's, geta compression check.

NiteRyda: Just checked out your cardomain page, VERy nice stang bro!
 
Blev said:
Yes, it's an Auto and Yes it's a catted pipe.


See numbers in sig. Our mods are pretty similar although obviously your compression is different. Did you dyno the car before the swap? The numbers are a little low, but nothing outrageous. I must feel much better than before though? :shrug:
 
Two things. First off I recently saw where the newer stang was putting down quite a bit less in the auto vs. 5 speed on the dyno, but the auto would sqeak it out in the QM, so #'s arent everything. BUT on the other hand I have seen anywhere from 10-50 rwh from it being tuned correctly. They were professionals tuners that were using a laptop. They ran the numbers and lines on the laptop as it dynoed, then adjusted everything, then re-dynoed.......wallah.....same mod as before the tune with numbers way higher because everything was calibrated correctly for the new piece/pieces. I would say there is probably a lot of usable HP lost in there somewhere.
 
007 said:
See numbers in sig. Our mods are pretty similar although obviously your compression is different. Did you dyno the car before the swap? The numbers are a little low, but nothing outrageous. I must feel much better than before though? :shrug:

are your numbers after all those mods were done??
 
My bet is a qualified tuner would get good numbers out of your set up.

Did you dyno the car before the mods? Cause it's not neccessarily about the number at the end of the day...it's about the gains made.

Get a tuner on that thing. You've given it the ability to handle more power...but without getting it properly tuned...you haven't modified the "brain" (aka ECM). You'll get some peace-of-mind to boot...cause you'll know exactly what going on with the car. :nice:
 
christiesledd said:
are your numbers after all those mods were done??
I think i made a few changes since, but basically everything was as in sig. My chip has only 3 degs timing, and doesnt do a lot. Correcting for the drivetrain loss, I'd be making 247rwhp thru a 5 speed which is pretty normal for a bolt-on car with a crap tune. 4.10s also drop your dyno numbers slightly.

I ordered my BBK shortys, and I might get a dyno afterward and have the chip tweaked a little.
 
mine was only like 250 hp before getting SCT tuned. My tune is not aggressive either, my tuner said he could get another 10-20 hp out of it if he advanced the timing further. So I would look for a shop that has SCT tuning capabilities. Cams also help a lot but I know you probably dont want to tear into your engine again.