Naturally aspirated

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BLaCk-40th said:
I want to squeeze out around 375+ hp out of my 4.6 on just engine alone.Would that be a hard task to accomplish? If not how should i go about doing it?

Nobody I know of has put down 375 rwhp. The fastest 2v NA GT runs a 10.xx and I think he only puts down around 350 if that. If you want 375 flywheel horsepower I'm sure that is possible.
 
well define whether it is rwhp or flywheel hp. i know of one 2v doing 330 rwhp with everything including a p-51 intake. if you want rwhp then you will need $$$ to do so. it takes cams, heads, intake and every bolt on peice to come close.
 
Its possible, but you'll be spend lots of $$$$$$$$. You'll need to port the chit out of the heads, use really big cams, run a very high compression ratio, have the bottom end balanced and blue printed(this may require new rods and crank to go along with the pistons), full exhaust, bigger intake and prolly a few other things Im forgetting.

In the end, it will be better to buy youself a KB than doing all this.
 
Your only other option is to stroke it. That will give you some extra displacement. Then toss on your h/c/i combo, and every other bolt on. I would think its possible to get 350+ if you stroked a 4.6 to a 5.0, and did all that.
It would be easier and cheaper probably to go with forged internals and a KB, but I guess thats just me :D!
 
BLaCk-40th said:
I want to squeeze out around 375+ hp out of my 4.6 on just engine alone.Would that be a hard task to accomplish? If not how should i go about doing it?
ignore the rest of them. Yes its of course its possible.

The question is whether its feasable.

Even the old Rover V8 is good for 90bhp/litre for a 4.0 race engine.

It will be possible to get the same specific otput from a 4.6 so,

4.6 x 90 = 414bhp at the flywheel, admittidly it will be somewhere between 350-370rwhp depending on how you work it out.

But this will be expensive to do as every thing apart from the block will need working, you will have to increase the engine rpms so a bottom end rebuild will be needed then some agressive race cams and top notch heads, combine this with as few ancillary devices as possible and a good exhaust and you'll be near your target.

HOWEVER

Apart from cost, it would likely be a pig to drive on the road and durability and reliabilty will certainly be issues.

n/a tuning for a street motor is one thing that really shows up the limitation of the modular engine in bhp terms. Peoepl like TVR, BMW and Ferrari all produce road engines which will make 100bhp/litre and still be drivable and reliable.

The DOHC heads will be much better as will an increase in capacity (bore NOT stroke) as you don't want and 'over square' engine, a long stroke and small bore means lots of low down torque but not liking high end revs and big bhp numbers. Big bore and short stroke less torque and revvy but bigger bhp numbers.


Unless there is some specific reason that you MUST have n/a your best and cheapest bet is to get a supercharger, even a roots blower will easily give you 350rwhp on a stock 4.6 2v SOHC engine.

If it has to be an n/a motor with big power maybe look at getting a LS1 powered car or an early Dodge Viper, both of those engines will easily make over 400rwhp all n/a and streetable.
 
as stated above it can be done, Steen Racing is building one for me as we speak that we're hopping makes @450 hp N/A but its not cheap by anymeans. this engine has a steel Cobra crank, aluminum rods, custom "domed" pistons, Comp "custom" ground camshaft, SVO heads, Riechard Racing intake and a whole bunch more. should be done in @3/4 weeks :D

so if you want to make that kind of N/A HP, you'll going to spend @$10k or more and let a good, quality shop do the work.
 
Steen Racing built the strongest 2v in the country, It put down over 700hp!
And they have one of the best tuners in the east coast working with them Ed Clark!
Yes I tuned my car there :D