I'm curious about folks opinions, what is the right amount of HP for a well balanced car: street and occasionally track usages, drivability, reliability, enjoyment, etc...
Mine has 410 whp (for 2380 lbs), even though I own a 1200hp GT-R, I wouldn't put more power on my FD (tuned by R-Magic Japan), for some reason it's already scary enough and wayyy scarier than my GT-R, and when you have a fast spool turbo, I find it more than enough on street.

 

My opinion is the 400-600 range. As long as the turbo is quick spooling enough to have a broad powerband and you have the traction. I've been enjoying my setup for a very long time at the current power levels (still scares me a little and never feels boring) I'm at 450whp on low boost and a little under 600whp on high boost. It's still manageable and fun on twisty roads and damn near terrifying on the straights to make you appreciate being alive.

 

What are your boost levels?

 

Hard to get too much power for the street.

With my 2,500lb FC with super responsive 420/420 rwhp/tq it felt like it needed more top end.

Couldn't even spin in 5th gear on demand on street tires with clean dry straight freeway.

OFC spinning 1-4th with roll on with street tires was enough for me to permanently keep it on race tires where it pretty much hooked 3rd gear and up.

So, maybe I am a hypocrite.

 

Then comes the reliability factor

 

I dont drive my car that much. Maybe once a week for a short drive. After driving the Honda CRV all week, the FD feels plenty fast at 320 rwhp.

The car is where I want it right now. Dont need more power. Dont want the cost and problems associated with more power.

 

^ This...except I drive F150 during the week.
Looks like you haven't found that balance
https://www.rx7club.com/new-member-r...oblem-1116930/

 

Downpipe and catback only, maybe a drop in filter. That's all you need. That's maybe 250 hp at the wheels using stock boost control.

 

How do you have equivalent horsepower and torque, are you holding back on your tune?

 

My FD should be right at the 300WHP mark, feels plenty fast for city driving. Currently feels well balanced but, I have stock suspension, brakes and wheels...

Maybe with the right setup you can make the 500-600whp range feel well-balanced

 

That's exactly why I've said it is scary.
First time driving a 2 way differential car though...

 

Big thing is the FD has no traction control system. A lot of modern cars with crazy horsepower numbers have some sort of traction control, otherwise they would just smoke tires.

While it's a fun party trick to floor it and have the tires light up in 1st or 2nd, it can get old if you actually want the car to accelerate forward and not simply turn expensive tires into smoke.

The rear fender wells can only take so much tire as well.

That said, I voted in the 300-400hp range. We've come a long way in making more reliable power with better apex seals and water injection but there comes a point where it gets to be just too much. It also depends on what you're looking to do with the car as well. But, a 350hp FD with a fat power band (twins or BNR's) makes for a capable, entertaining, and enjoyable car that you can enjoy every day without too much worry.

Dale

 

Yep

NO reason to have 400 HP if the tires, susp, brakes, trans, diff, chassis etc.... are not equipped to deal with it.

In stock form the FD needs: Bigger wheels and tires, brakes, sway bars and springs to get the most out of it or balance the already too small tire, light springs and small brakes for the power to weight out of the gate. Setup properly with cooling, brake and susp mods this car is one of the best ever at 250 hp, add 100 HP to that and forget about it you now have a 25 year old car that's keeping up with most of the best modern performance cars made in the last 10 years.

And there are people who want 450 RWHP (Basically doubling the original power that was already out of BALANCE....LOL)............PLEASE!!!! Do you also have the 25k plus invested in brake, cooling, trans, diff, wheels/tires, chassis bracing etc.....mods to support that power because if you don't you won't have a balanced car or even close

 

No, that is what you get when you max out the compressor on the EFR 7670. The 7670 compressor can only do 420-450rwhp depending on engine and dyno.

I could have had more torque than HP on this turbo but I ran out of injector and had to limit the boost to 26psi @4,000rpm.

 

Had to limit to only 26psi! That really sounds funny. Only 26spi lol

 

That is a necessity for good performance on a circuit, but not really for what most people use the cars for on the street.

Slap some MT Street Radials on stock wheels in the rear and you are good for stop light to stop light and highway pulls which is sadly what most people do.

When I am on the curvy roads it is locals in mini vans with trailers or truck full of split wood (losing its wood as it goes) or whatever shitbox they own that are keeping the pace through the turns.

Occasionally a motorcyclist.

Never once a "sports" car unless its one of my friends going to or from a race with me.

 

Completely understood.

I'm just balancing the car for the intended sports car use and it needs balancing at the stock power level.

 

deleted.

 

I have done a lot to my rx7 and I also own an rx8. Over time, perhaps its just age, I prefer to drive the rx7 in the 300-380WHP range and that is really on the top end.


I bet I could have just as much fun with the car and run it at 250WHP, what really seats cars apart are the tires, suspension and brakes. the power is really not that important. I can drive the **** out of the rx8 and I honestly don't think my rx7 is that much faster in the autoX tight canyon roads. Obviously on a large track with long straights power makes a difference but its not as much as people think. There is a certain amount of joy driving a car with not much power right on the edge all the time and beating other drivers in faster cars. It also takes a lot of skill to drive a really fast car....fast.


I have a pretty well set up rx7 in terms of brakes/suspension/etc.

 

The previous owner modified the FD for time attack so it's about 320 hp with light mods. I don't think I'd go much farther without investing in some kind of safety margin (e.g., water/alcohol injection), as it's getting to be a pain in the *** to source parts, etc. for engine rebuilds.

When adding power, you have to think about the limits of the chassis as well. Do you really want to add weight to the car with additional bracing and reinforcement, or do you want to stay within the limits of the stock chassis?

Also, my limit applies to twin turbos. I like the smoothness of the twins (but not the complexity), so your mileage will vary depending on your setup.

 

14psi wastegate
20psi low boost
32psi high boost

This is on a 6766 turbo on 93 and preturbo water/meth mix.

 

lol...me too.

 

The stock FD was/is a marvel of OEM 'perfection'...for the time. And while it still holds its own very well, the car responds well to a few more ponies.
Not that I've driven one, so this opinion is subjective only, but I would think a 400+hp FD would be a bit of a handful on the street in normal conditions. As others have mentioned, similar modern cars have a host of electronic 'help' to keep them from trouble.


I just read a story a couple of days ago about a guy wrecking his 1-of-499-made Ferrari 430 in his first hour of ownership.


Ferrari crash: Newly-bought supercar gone in 60 minutes | FOX6Now.com

 

I think that about 300whp is good for these cars for street driving. I'm at 350whp on a mustang dyno (~400 on a dynojet) and I find it hard to enjoy the car sometimes. A quick pull to red line in 3rd and I'm way above the speed limit and have to slow down again.

 

With 255's in high-perf. summer tires I already have to be careful applying power on corner exits or a curvy free-way on-ramp. Not sure I'm a good enough driver for more than 300 whp...right now.
Car's fun reliable and fast enough as it is. Why pull the tiger's tail?