Dissapointed JMM StreetFighter results - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

hot EA · 02-04-2005, 18:52

hey, just got my car dynoed, and with the streetfighter head cam and gasket kit( i already had an exaugst and extractors and it pulled 143hp at the wheels) with the head it only pulled 20 more hp on the dyno at peak power. it ran 163 hp at the wheels, the only thing that was changed was the complete head to an EF-EL head with 4.0L rocker gear, JMM streetfighter cam and head work, performance valve springs, adj. vern cam gear, new timing case chain, gear and guides, it was installed by a good mechanic and ran on a less than 2 year old dyno. and a new rotor putton and cap was also installed. Any suggestions on what it could be the problem could be. Could it be because i am using a CFI dizzy (i did the multipoin upgrade and didnt change it, the first run was done with that dizzy). could it be becuase i need a EF inlet manafold? could i be leaning out, because if you look at the graph my torque and power are pretty flat from 4000RPM to 5000RPM. Please take a look at my graph and post any suggestions. Thanks In Advance Josh

http://www.fordforums.com/attachment...chmentid=30150

MrMercury · 02-04-2005, 21:46

josh hows the car feel on the street after you fitted your streetfighter kit compaired to before
i fitted a streetfighter cam kit to our au2 and you can definatly feel the extra stick compaired to before.
jake

81foXDwagon · 02-05-2005, 01:39

Was a tune done on the dyno after the dissy cap and rotor replaced??
This will change the timing, as the contacts will be better, and the spark may be transferred at a different point. (Dont just go by the 10degree base timing will all your extra gear, get it tuned on a dyno).

I doubt your dissy would be at fault, as I have found, they work or they dont. If it idles fine, and revs fine without missing, it most likely is fine.

Also, (probably not worth saying but) what fuel were you running in it. Could just be a bad batch??

Dont worry too much about the result, its all about how it feels to you on the road

Good luck!

Martin · 02-05-2005, 05:09

Did the dyno show Air Fuel ratio at all?

badxr6 · 02-05-2005, 05:47

Quote:

Originally Posted by hot EA

hey, just got my car dynoed, and with the streetfighter head cam and gasket kit( i already had an exaugst and extractors and it pulled 143hp at the wheels) with the head it only pulled 20 more hp on the dyno at peak power. it ran 163 hp at the wheels, the only thing that was changed was the complete head to an EF-EL head with 4.0L rocker gear, JMM streetfighter cam and head work, performance valve springs, adj. vern cam gear, new timing case chain, gear and guides, it was installed by a good mechanic and ran on a less than 2 year old dyno. and a new rotor putton and cap was also installed. Any suggestions on what it could be the problem could be. Could it be because i am using a CFI dizzy (i did the multipoin upgrade and didnt change it, the first run was done with that dizzy). could it be becuase i need a EF inlet manafold? could i be leaning out, because if you look at the graph my torque and power are pretty flat from 4000RPM to 5000RPM. Please take a look at my graph and post any suggestions. Thanks In Advance Josh

http://www.fordforums.com/attachment...chmentid=30150

it could be lots off resons why but you need to put the multi piont dizzy in because they are different

Grant Porter · 02-06-2005, 00:39

I just did nearly the exact same thing as you did to your car. Except I went with crow cam and custom porting of the head and intake manifold - also machined the head to give it a higher comp ratio. On the dyno I got about 20rwkw, which isnt the cheapest kw per dollars ratio but it was the next thing to do and I could definately notice the difference. My mate has an XR8 xh ute and he used to eat me by about 2 or 3 body lengths over the quarter and now its touch and go between us. The best thing that I noticed out of the mod was the freeer reving - It used to max out at about 5250rpm, now it pulls past 5500rpm and makes an awesome sound!!!! Just by looking at your dyno graph it looks like the vernier cam gear can be retarded/advanced a fly shit to smooth the power curve out a bit - but its pretty close to the mark. Also, when I dynoed it I had to change the timing, its on about 15 now and ive got to run it on 98 octane fuel because of the comp ratio. Every car is different, but its definately worth adjusting. All in all, im happy with the feel of the car, it really starts to bark when you give the throttle a squirt! And it surprises a few performance cars aswell!!!

loxxr6 · 02-06-2005, 03:46

I notice the dyno is an MDX one.

Some guys here in Sydney went to a dyno day at the place that did my cam install (dev 5 , but no headwork). Apparently this type of dyno does some weird stuff like average out the power gained or something. Cars run on a mdx dyno on the day scored way lower figures than their previous runs on Dyno Dynamics dyno's.

Try getting ur car on a Dyno Dynamics one and see what happens. My guess based on what ppl have said is that you'll possibly get a higher reading. Either way from where I can see it you look like you have made a decent gain across the range. Don't sweat on peak power, look at overall.