Just curious what your opinions are on performance upgrades. What and how much for a modification with a real noticiable boost. I'm talking street machine here.

I've heard intake and exhaust mods yield minimal gains.

Thanks in advance
Bill

 

nitrous.

 

Track Time

AKA: MOD of the owner

 

also the Racing Beat intake seems to provide very good gains for the price when compared to other items.

 

My experience has shown me that a mild 55 shot works well without needing PCM mods. A lightweight flywheel also provides marked improvement. Maybe next would be a cat-removal pipe or high flow cat. The factory cat becomes quite restrictive above 6,000 rpm's. Before all this I usually suggest new swaybars and springs because more power is pointless in a car that wheelhops like crazy from the factory. The Racing Beat intake is said by many to provide tangible improvement and that it is worth the money. Cat-backs are more for sound than performance so their value is questionable, especially at prices between $600-$1,000.

This whole matter of modifying the RX-8 is boiling down to one main consideration; how much time will you spend above 6,000 rpm's and is it worth the trouble and money to improve performance from 6-9K on your own RX-8? In daily driving I rarely go above 4 or 5K but on the weekends I race and spend all kinds of time above 6K and often as high as 9,500.

CRH

 

I would say tuned CZ. People can reliably get 20+HP out of them. $300 used CZ / 20HP = $15/HP which is better than anything else I've seen. The RB intake is about $300 and gives 15HP (if you believe the 1 dyno that I've seen out there) = $20/HP. I think midpipes, nitrous and FI are approaching $25/HP to over $40/HP.

Charles, mind giving the $/HP on your nitrous setup?

-MD

 

Nitrous or tuned Canzoomer Piggyback ECU. No way the RB air intake is giving people even close to 15 hp. RB is claiming 3-4 hp. The people that are getting them might want to believe massive hp gain, but I have yet to see a non-seat of the pants dyno that gives anywhere close to 15 hp. Another item would be a testpipe/midpipe. Good for about 8 hp for $200 (or less if you get a muffler shop to make you a piece).

 

I was thinking RX-GR8, Abbid, and Omicron.

 

^^^ thats funny...


BTW: Here's the one dyno I've seen

 

Fanman--that one dyno shows the car has 15more HP or so over a stock RX8--however that car also had an exhaust system and maybe pullies--but the thing is the car was dynoed several months and many many thousand miles apart. My guess is maybe 5-10HP for the RB intake.

 

I seriously have doubts that any intake gives even 5-10 hp, especially when the company (RB in this case) claims about 4 hp gain. Wouldn't it be in their best interest to claim 10-15 hp ? They would be selling them by the truck load. A dyno done months apart with additional parts is not even close to being scientific or conclusive. I can show you dynos where a stock car dynoed 10 more hp, of course the weather was about 30 degrees different. I'm glad MadDog showed me a dyno (and I have a lot of respect for other posters like Omicron), I'm just very skeptical of these hp gains. I guess I will wait until the article by Polak in RX Tuner, for definitive #'s.

 

I do not even see RB claiming that..Actually, on the website they make no claim about HP, other then an indirect claim that removing the MAF screen provides 1HP.....as of ~ 1 week ago.

With all the testing they have done to build this, you think they would be able to post their Dyno chart on it....or report the HP gain flat out.

 

Dre has a good point about the other mods and the time difference. I also have seen zippo claims from RB on the gain. For what its worth, I am getting my REVi tomorrow and I plan to do before and after dynos on the same day. If that plan holds, I'll post 'em.

Back to the thread topic: I still see the tuned CZ as the least $/HP.

-MD

 

RB emailled me: "I am working on preparing the performance data for display on the website. Our dyno computer provides numerical data, not the graphical style that you normally associate with a Dyno Jet chassis dyno."

Here is what they say in response to the power they are seeing and the application to an auto version: "We have yet to take a look at the auto version, we need to evaluate one to determine the differences between the models. Until then, we can only make a fitting recommendation for the manual cars. On the higher power engines, we are seeing 3-6 HP gains, with most of this at the top end."

 

Your guess is totally wrong my friend.... Fanman is right on this.
the dyno everyone is talking about is not a good comparison.

 

Thanks for all the great info! So what I am gathering is before doing mods, have deep pockets, there's no quick and cheap HP fix and if there was, I'd have to blow a wad on suspension upgrades...

 

The 4 hp claim came from a previous post in a previous thread by Jim Langer, when people were pestering him on when the unit was coming out. In the post he said it would be about a 4 hp gain.

 

or, if you want to stay PC and, you can use a hi flow cat with the midpipe.

 

So far the most noticible gain came with the addition of the high flow cat. The intake and catback alone did little.

 

Keep your tyre pressures up (above 35psi) and remove any crap from the boot (ie, spare wheel).

Can't beat that bang for the buck .

 

Actually its close refer to my previous post. "3-6hp" and my point for pointing that dyno out is that it *is* inaccurate because of the differences between the two dynos--I should have made that more clear :o .

 

Why does the mod have to be directly tied to horsepower? It may be harder to quantify, but the biggest bang for the buck, at least in terms of lap times might be a fatter &/or stickier tire; or tower braces; or a set of beefier front and rear stabilizer bars and/or springs.