I posted this at some other forums, and I want to give Rx7club a chance for some input. I was curious what you guys would think. I've been surfing the forums the past few weeks and there seems to be a lot of 6-port turbos popping up. I have an S5 engine with 65,000 on the odometer. The previous owener upgraded too 3mm apex seals, and rebuilt. I do not know the mileage on the rebuild. My question is, do you guys think I should do it? I have all the necessary tools, skills, and available help for those troubled times. What experiances have you guys had with turboing the 9.7:1 compression ratio. I want to follow aaron's guide mostly. Thanks for the input.

 

If you had the skills, as in, designing your own turbocharged system, you wouldn't be asking this right now

This has been talked about ALOT, however, the S5 turbo is more rare becuase of the even higher compression ratio. Honestly, you could totally get away with stock boost levels from an S5 turbo by using a good intercooler setup, and of course the highest grade octane at the pumps.
Just search it, I could type up about 4 paragraphs of **** about what will work, what will not, what problems to expect, and what I would recommend, along with everyone else here. But all that **** has already been talked about.

Like I said, with good intercooling, you could be running 10.5:1 rotors if they existed. Obviously there is a point to how much boost you want and how much reliability you want, a delicate balance.
Me personally, im aiming for only stock boost at the moment. With the higher comp rotors, 6 ports and a very open exhaust, im expecting some decent numbers with 5psi (decent numbers for me, remember im an NA guy )

 

http://www.aaroncake.net/rx-7/naturbo.htm

 

I'm probably going to run in the neighborhood of 8psi. Can't wait to get started. I'll be sure to take pics. I just hope it warms up a bit around here in michigan.

 

no offense to arons method but i would use the tii intake manifold also to avoid having to modify the frame. like black plague said stock s5 trubo will provide a good amount of boost for that motor and wll produce some good power with that compression ratio, i'd consider a stand alone tho although you can get away with an safc and thats what i'll do casue it's cheaper and i'm broke

 

boost controller!!! If you don't use one of those, well, yeah.... not that i would know... but, uh, not good...

 

Uhm, what? Boost controllers only add boost to what the stock wastegate is set for (which is usually 5.5psi), the only thing it does is make it boost higher. What's not good about not using one?

 

its funny becuase you don't know. If he uses a boost controller, that would mean that he wants more boost, not necessarily a good thing with a high compression engine. Like I said, start with stock boost and see how that goes. You WILL need a fuel controller.


Im personally using the TII manifolds and porting them so they mate up with the aux ports. Cutting into the frame, or even cutting up the LIM to make the turbo fit is a waste of time IMO..

 

Why modify frame to use NA manifold? Turbo to manifold clearance issue requiring a spacer?

if thats the case, you can modify the NA LIM to clear the turbo, if you are willing to give up the acv&cv junk. You can maintain aux ports helping low end (also quickening spool up) this way too. Just hack off the part of the manifold that the acv&cv mount to, weld shut the little ports that went to it, and move on. The NA manifold can be made pretty slim actually, if you know how to modify it.

 

The aux ports are too much of a PITA to keep for such little benefits. Ditch them and their rods & sleeves!

 

8psi, no problem. Just don't skimp on the cooling and don't beat on it.

I have a 4 port turbo with 9.4 compression rotors. Let me tell you, you will not regret it if you do it right. Higher compression will put a smile on your face.... Very responsive.

 

Thats the key man, I hear you! heh. I saw a video of an 11.0:1 compression turbo tegra that was pretty damn fast. I'll have to find that video again, it was insane.

 

hmm this thread gets me wondering, i'm going to be going through my 13BT this weekend, i wonder if i should toss in a set of n/a rotors to up the compression since it is a S4. give me your input!

oh, and sorry to jack your post.

 

have you started on the project yet? just asking cuz i'm planning to do the same to my 88 n/a by using the tII manifolds. i wanted to port them right away but my dad wants me to hold off untill he checks to see if there will be issues of coolant seaping in the intake even after comparing the gasket to assure him. post pics if you can.

 

I'm still at a toss up on what methods to use. I mean the tII manifolds would allow me not to cut the frame, but the spacer would work too. I have an extra set of s5 N/a manifolds which would be a waste to keep. Once again, I wish it would warm up!