5L HO...looking for more HP

[jayh]

I have a Factory Five roadster that I have owned for about 18 Months and am now on the quest for more power. Put it on the dyno last week and it produced 204 HP at he rear wheels. Basicly a stock motor. Looking to modify to produce 300+HP. Looking for any and all sugestions on how I can reach my target, what you may have done, or didn't do, or should have done. Thanks

[frankeeski]

Basically a stock motor doesn't really give us much to start with. Please give us some details on the motor. Is it a donor engine with ?????? miles? Is it a crate engine from Ford Racing or other manufacturer? Give us a rundown of the speed gear you may already have bolted on as well. If you purchased a previously owned car, knowing the specs may help you from grenading the engine from simply bolting on speed parts.

[willy]

It is not to difficult to get 300+ I got some stock GT40P heads make sure they are the "P" ones, and a good cam I used a Ford Raceing 303, also trick flow valve springs

[Bob Cowan]

You need to do two things to make easy/cheap power. "easy" and "cheap" being relative terms.

Increase compression. Increase air flow.

If the engine is in good shape with low miles on fairly fresh build, simply add a blower. A week end's work and a dyno tune.

If the engine is a bit tired, then overhaul the whole thing, and add better heads, intake, and an aftermarket cam.

If you put a blower on an old tired engine, plan on doing a complete rebuild fairly soon.

[Mike N]

For what you have why not consider the spec racer top end engine upgrade package from Trick Flow, heads, cam, intake etc. There's plenty of dyno data on here and also a bunch of guys running the same set up so you know you will be able to get tuning help when you need it. Proven to give comfortably more than 300 HP at the wheels

[jayh]

Yeah guess I omitted some needed info. Whoops!! Donor 5.0 HO. I purchased the car without documentation or knowing a lot about it's history. No added speed parts. In 18 mo I've put almost 2800 miles and its been very reliable and runs strong.
Thanks for your input.

[MPTech]

What year is the 5.0L?
EFI or carb?
What accessories are you running? PS / PB?

What rear-end and gearing does it have? (may not increase HP, but could improve the FEEL with lower gears dropping from a 3:27 to 3:55, etc.)

[frankeeski]

Yeah guess I omitted some needed info. Whoops!! Donor 5.0 HO. I purchased the car without documentation or knowing a lot about it's history. No added speed parts. In 18 mo I've put almost 2800 miles and its been very reliable and runs strong.
Thanks for your input.

Well, with that, I would be a bit cautious about simply bolting on performance parts without doing a bit of investigation. Start with a compression test and maybe even a leak down test as well. If the numbers look good, then a letter cam from Ford and a nice set of heads would be a good place to start. Match that with some larger injectors and a mass airflow sensor tuned to the injectors to go with it and you should hit your target number of 300. Best advice I have seen from the above replies is changing the rear gearing. If the car is still running 3:08-1 ratio gears with a donor engine and trans then a set of 3:55-1 will really wake up that set-up. If the car already has a good set of gears the performance upgrades I pointed out will be very well suited to them.

[mavisky]

If you're willing to dig into the motor I'd cast a strong vote for the Trickflow Top-End kit. It makes it very easy to make the power as it's everything you need to get the hp to where you're looking for it to be and sounds great to boot.

[skullandbones]

Hi Jay,

The 5.0 HO is a nice little engine. I was going to go your route with a 60k HO but changed my mind at the last minute and got a 302 rated at 300 hp. IT was basically a stock engine configuration with a nice street/comp cam. The dyno curve was very consistent, too. Then I changed out the E7 heads for GT40P like willy. I used the spring set and exhaust valves from the E7s (matched to the cam). I did some extensive porting on the exhaust runners but the rest matched well with the Holley intake and BBK headers (I port matched everything including the throttle body 75mm). The GT40Ps give pretty good breathing and added compression with the 58 cc combustion chambers. If you don't mind the work, it's one way to get to where you want to be. I know mine sounds nothing like a stock engine and I will soon know how much hp as it will be dynoed when I have a few more miles on it. It runs strong even with the 3.27 gears. Go with 3.55 gears if you haven't already. I was going to but I like it the way it is after driving it a while. Good luck on your upgrade. But it sounds like you have gotten your share of fun out of it as is. WEK.

[FFRSpec72]

If you're willing to dig into the motor I'd cast a strong vote for the Trickflow Top-End kit. It makes it very easy to make the power as it's everything you need to get the hp to where you're looking for it to be and sounds great to boot.

Agree, I run in the Challenge series in NASA and run the TF top end package, I get 331rwhp, 330 torque, no issues all runs and no engine issues, the price was right, about $2700

[Avalanche325]

I was also going to suggest the Challange top end package. A well tested configuration.

[dhungerf]

I went with the following
Eddlebrock performer heads
B303 cam
65mm TB
Ford Racing intake
4 into 4 headers
3:73 rear