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View Full Version : Bolt on performance improvement questions...



Waffles
04-21-2008, 04:15 PM
Take a 96 Cobra (happens to be what I drive). Stock, the car makes essentially 265-270whp, so I've read. My question is about bolt on HP mods and how the effect eachother etc.

First, C&L claims that thier MAF adds about 20whp.
BBK claims 7-12hp (probably at the crank which is about 6-11whp) for the twin 65mm TB.
MAC claims 20-30whp from thier LT and off-road H-pipe.
Underdrive pulleys are supposed to free up 8-10whp.

Then several speed shops tell you you're looking at maybe a 10-15whp total gain from all of the above. I know it's not as simple as adding them all up, but what gives? At least a few of those manufacturers have dyno graphs. So, C&L gets a car up to 280whp. Then you drop on a BBK TB and drops it back to 274wph? Are thier claims just false?

PaulFiveOh
04-21-2008, 04:32 PM
Keep in mind that the manufactures horse power numbers are under perfect conditions and under controlled laboratory enviroments.

5.0calypso93lx
04-21-2008, 04:40 PM
Take a 96 Cobra (happens to be what I drive). Stock, the car makes essentially 265-270whp, so I've read. My question is about bolt on HP mods and how the effect eachother etc.

First, C&L claims that thier MAF adds about 20whp.
BBK claims 7-12hp (probably at the crank which is about 6-11whp) for the twin 65mm TB.
MAC claims 20-30whp from thier LT and off-road H-pipe.
Underdrive pulleys are supposed to free up 8-10whp.

Then several speed shops tell you you're looking at maybe a 10-15whp total gain from all of the above. I know it's not as simple as adding them all up, but what gives? At least a few of those manufacturers have dyno graphs. So, C&L gets a car up to 280whp. Then you drop on a BBK TB and drops it back to 274wph? Are thier claims just false?

I'd recomend browsing around over on www.svtperformance.com/forums . Good bit of info on bolt ons for 96-98 4 valves.

-JLT CAI
-March or Steeda Pullies
-4.30's
-X pipe and a nice catback

I remember reading that the TB doesn't do much at all NA. I had a bad experience with a C&L meter so I wouldn't recomend them personally.

Waffles
04-21-2008, 10:39 PM
Well, I may have found the answer to my question today. Not entirely, but pretty damned close so I thought I'd let anyone else know.

I called C&L today and asked questions about my MAF meter. The guy seemed very knowledgable so I started asking questions. Their dyno claims 20whp increase on peak hp over stock. So I asked him what I could expect with the BBK throttle body and LT headers. He told me I'd have to dyno it to tell.... and here's why.

He showed me another dyno graph that claimed 28whp over stock on peak hp. However, in some places in the curve the gain was only 5, while other places the gain was 35+. He said, you don't lose HP by adding one thing or the other, it's just that hp gains can be distributed throughout the power curve. HP is simply not a linear measurement, it's a measurement in relationship to something else.... RPMs. So part of the 25hp gain over stock that the headers might give me isn't lost because I also have other mods. It's just that the hp might have been increased somewhere other than where peak hp is made.

Makes sense to me.

As far as the projection being too low entirely, he thinks it was just a bad estimate from the speed shops.

bobtsgt
04-22-2008, 08:23 AM
A nice intake like C&L and some long tubes with an H pipe will give you some nice gains. I would hold off on the TB and if you get a deal on some pulleys do them at the same time as the headers and intake. That should yield a pretty healthy gain. Remember just because they sell it doesn't mean you need it. At least right now in time. You don't really need a new MAF unless your pegging out the stock one which you won't staying N/A.

Waffles
04-22-2008, 03:19 PM
I've actually already done the TB and MAF w/filter. I picked up pulleys Saturday and my headers with offroad H-pipe should be in today. I love the car, don't get me wrong, I just haven't been as happy with the performance as I think I should be.

I'm likely going to have CS dyno tune it next week and see what they can squeeze out of it. I've got 100 shot of nitrous on it also, but really don't use it since it's not been turned.

BTW, Craig gave me a hell of a deal on my exhaust. :D

bobtsgt
04-22-2008, 03:25 PM
cool. dropping the K member isn't that hard to do either. Just have a buddy around and you should be able to knock out that exhaust in days time.