4.6 vs 5.4

[mvp...]

I was hoping for some opinions,I have a 99 cobra motor and a 08 gt500 motor and I wanted to know what you thought would be best for a hopefully low 9 sec streetable notchback with and automatic?I haven't decided on which power adder as of yet but pretty sure it will be a turbo(single or twins).I know that I'll have to get either motor built but which do you think would be best to achieve my goals??thanks for any info!!

 

[Bill]

It sort of depends on what your budget is. With both motors sitting around, I would assume that you have a reasonable build budget. On the lower cost side, the 99 Cobra motor is a reasonably easy install, and On3 Performance makes a turbo kit that can be adapted with very little refabrication work. Their kits start around $1800 and can be very streetable/adjustable for under $3500. 9 seconds depends on a lot of different things, but either engine can make enough power to get you there. I don't have any experience with swapping a motor as new as your 08, but I have seen them make some serious power in an S197 chassis.

 

[mvp...]

Thanks for the reply,I have been racking my brain trying to decide which way to go...well I'll keep looking at the many builds on here and hopefully it will help me decide and thx again.

 

[Bill]

My advice to you would be to cash a reality check. This install can be done simply and easily, but most decide to do things that make it complex. If you like to drag race, do it the easy/quick way first. That gets you back out to the strip and lets you enjoy your work. You can always upgrade once you have a good set of bones together. To get to sub-10 second passes, the Maximum Motorsports drag setup, a six-point roll cage, either motor (power adder required for the 99) with a built automatic transmission, and a lot of weight removed from the chassis will get there. Two-stage nitrous on the 99 would be a really cheap path to the 9s. Check your local track for bracketed safety requirements. Most, but not all, use the NHRA guidelines. Don't neglect your suspension or chassis prep. Remember that when the front end twists, you alignment changes, causing the car to not go straight. If it lifts the front tires and they don't come down at the same time, right turns have been known to happen. The MM setup, some good stuff from Stifflers, a little bit of wrench time and you can have 9-second street car. Doug's Headers (see Justin at JBA for these) makes a nice set of power exhaust cut offs that will allow you to run through the mufflers when you want and switch to open side exit on demand. Some states allow this and some don't, so check your local laws if you need to. If your reality check includes a 9-sec car that handles like the ones on Fast-n-furious, we need to talk off-line.

 

[mvp...]

Thanks that's good advice because sometimes we do have the tendency to over complicate things!!