whats it gonna take to make reliable 450HP?
 

Some background info, I recently purchased a 93 rx-7 while being deployed in iraq, a buddy of mine took care of the deal while he was on leave, and I get home from iraq in about a month or so. This is my first rotary engine and ive been trying to do as much research as possible to ensure that I do things right, im a novice at automotive, never was exposed to it much when young, but am always trying to learn more when I get the oppertunity. the rx-7 makes 284HP and 221 Torque, i believe the boost was at 12psi at the time but not too sure. The compression is all good, there was a problem before with low compression on one side in the rear housing but he used the auto tranny fluid trick and that seemed to fix the problem(stuck side seal?). Below is the list of mods on the engine and suspension that I was given:

Engine:
Greddy T-78 Turbo kit and Innercooler
Greddy wastegate and Type-R blowoff valve
Full Blitz Nur Spec exhaust
Apexi Power Fc computer
Aftermarket pulleys
ACT clutch and new flywheel
Upgraded injectors and Fuel pump
Hks air filter
New alternator

Suspension:
Full HKS race coil-over suspension

Brakes:
Brake performance custom made dimpled and hatched rotors

Im aiming to keep this a daily driver, reliable, and am shooting for 450HP in the end, and am looking for any and all advice I can get from the knowledge of you experts here, anything and everything. Anything you can tell me about reliability mods I will need and what I will have to upgrade for my target HP, and suggestions for suspension and anything else would be appreciated too.

Sounds good, but the T78 is a lag monster. A newer ball bearing turbo will bring in boost several thousand RPM sooner.

hmmmm so what would you suggest for a turbo then?

The GT35R is a very popular turbo. You might consider retrofitting that in place of the T78.

As for plans, I would *not* rush it. If the car checks out, drive it for a while and do maintenance. Maintenance on this car is much more than oil changes - you may find little things to fix in the transmission, suspension bushings and pillowballs, fuel filter, coolant hoses, etc. I would definitely add a water injection or meth/water injection kit to the car before turning up the boost. Given what you've said, put reliability ahead of performance mods in all cases.

You have some fuel and cooling mods already in place, so it will depend on exactly how much fuel and IATs whether it's sufficient to get you to 450hp. I would install water injection and take it to a rotary tuner. The tuner will get things optimized, and from there you'll have a very good idea what more is necessary to get you to 450hp.

yea im not too familiar with the water injection or water/methanol injection mods, what exactly do they do, and are they for daily driven cars? I am also unfamiliar with the sencondary fuel injectors, the main injectors supply fuel when the car is at idle and lower demand? and the secondary injectors supply higher amounts of duel when there is higher demand for it in the engine? I had planned on going through and doing all the reliability modifications before I start pushing for more power, so im interested in any imformation that could be give, in read many of the posts on reliability mods on these forums already but anything else would be awesome. is the pre-cat on the rx-7 the only cat converter on the exhaust system? I hear many people take the pre cat off and go with a straight pipe, whats the word on that?

In my opinion, a GT35R isn't enough turbo for 450HP. The boost needs to go too high to make it reliable. I just tuned a stock port RE on a GT35R and made 380 RWHP on 18 PSI on what I would consider a good tune. In the GT series, I think a GT40R is far more suited to 450 HP. Should do it around 15 PSI. My GT4088R makes just over 400 wheel HP at 13 PSI.

Aaron,

Glad you chimed in as I'm not well versed on the ceiling for a 35R. I just know they spool very well and they are great for cars not looking for huge hp numbers.

AI is old technology being applied with more advanced injection technology than ever before. It cuts down knock levels, lowers combustion chamber temperatures, and keeps the engine internals super clean. If it's a water/methanol blend you will also see huge drops in intake temperatures and the meth will boost fuel supply (it works with your engine tune). When working properly the chance of popping a motor due to minor tuning mistakes or bad gasoline drops to almost zero, and you can install On ordinary boosted engines these are nice things to have, but on the turbo rotary they are golden. There is a great thread to read about it written by Howard Coleman (link can be found in the 3rd gen FAQ) and a whole other section of this forum devoted to it.

In the past AI was pretty basic: under boost, you add water. Newer systems offer the control to inject a little water under light load and more water as you approach max load. This makes the system much more streetable and improves the performance of the system at the low and high end.

Dave

sounds like a good investment, how often would i have to refill the water/methanol injection tank on a daily driven?

I looked around a little bit online for water injection kits and someone mentioned snow performance, anyone used the Stage 3 Gasoline MPG MAX® Boost Cooler® kit or know if its any good or worth the price?

T04R should do it!

Fuel pressure gauge, egt gauge, and a nice wide band I think are good items to have