rkostolni

The turbo may have the potential to make 450whp on a piston motor, but a rotary requires more lbs of air per hp than a piston engine does. A piston engine typically rmakes 10 hp per lb of air. A rotary engine makes around 7-8hp per pound of air. I don't think you'll break 320whp, but I hope you prove me wrong.

alex

man i hope so too

IZoomZoomI

well, at least you know you won't run into too many reliabilty issues, since you did pay to get it tuned and the motor prepped properly. I rather have a peace of mind than a whp number. But if it's worth 30k thats a different question. Get that thing dynoed! Also wasn't it addressed before that it isn't the limits of the turbo rather the motor? Because there are dyno graphs of other higher flowing turbos showing hp/boost dropoff at the topend.

rkostolni

You're confusing some issues here. The boost falling off and the power falling off are two different although related issues. The Greddy turbo can't hold boost largely, if not entirely, due to excessive exhaust gas pressure forcing the wastegate open. This is because the hot side is too small. PTP and SFR hold boost fine, but their power still falls off after 7k. This appears to be a limitation in the breathing capability of the motor and not the turbo.

The issue here is that shortly after you exceed the 300whp mark, relatively large increases in boost pressure will only net marginal increases in peak power. I haven't seen an air temp plot yet to confirm that the turbo's efficiency is plummeting, but that is most likely what is happening. Indicating it has exceeded its flow capacity.

alex

well, in a couple weeks (after re-break in) we'll find this all out. I'll try to ask if there's a compressor map for this turbo, i assume when blast called Trust about the specs of the turbo, i can only think they got the compressor map of some sort. well, anyhow, i just want the car done BUT as a contigency, i am looking into a new turbo, maybe used but who knows, we shall see.

alex

Kel Rx8

13brew internals ? and why 30k- not bashing but thats alot for the project you have.
I hope evrything works out and you make a sufficent amount of power.

alex

Well, total for engine work was ~$13k (including turbo costs, parts, labor) the rest was total installation and part costs for everything I ever bought for the rx8 which includes 2 sets of rims, 2 sets of coilovers, body kit, etc.

so, it wasn't all 30k in motor work , I'm not that rich , I wish i was though.

IZoomZoomI

13k for all that work isn't that bad. Yeah when I saw 30k, can get a corvette for that price.

coll

thos are some nice rim. could u give me the name/brand they look sick

hitman408

what shop is that?

alex

I don't know the shop's name, i'll find that out.

the rims are racing hart cx 19"s (9.5/9) and those will be for sale after i get my other set put on.

lourx8

Did you break in the engine yet?

alex

Not yet, (preferred) 1000miles is really hard to put on a car when its 700 miles away and when you're asking for favors down south break in is pretty tough .. under 4K RPMs. My buddies down there willing to break in my car thought this was pretty hard to do considering the boost kicks in at 3000rpm and from what I was told, is neck snapping.

So, i'll have some pics of my new rims and other items pretty soon.

XDEEDUBBX

alex, i can break it in for you! im not to far from that shop..let me know! hahahha

you can trust me, i have forum credit, just look how many posts i have! hahaha

alex

do you know where the wheel supply is? If you do, you can definitely work something out w/ the person whom I entrusted my car with there I'll ask him what his travel plans are regarding the car and if he's busy (which I know he usually is) I'll see if one of the forum guys can do some break in for me.

lourx8

Why dont you disconnect the turbo during break-in by attaching your air filter to your throttle body and drive it like that so you wont get on boost. Is that a bad idea?

alex

i was thinking the same thing when I heard the turbo was kicking in. I know Wakita knows a great more than I do, I just assume that he knows what he's doing. but I already asked him about disconnecting or at least dropping the boost. It could be he already dropped the boost a great deal . but I am concerned to say the least.

lourx8

That is what I did when breaking my engine in. It took me about a week. Remember to change the oil at 500 miles.

MadDog

Its really not hard to keep out of boost on any turbo'd car. Just don't put your foot in the pedal. No big deal.

Dro

when your foot looks like that ^ it might be a problem

SpyderX,Inc.

hey dude, where can i get a manual throttle body and find upgraded seals for the 8 motor?

alex

The throttle body the shop found a compatible one and the cabling they did 100%. All i know is that it came off an 850 Ci; how they got it to work, I don't really know

The seals, if you call it an upgrade, were off an RX7 and so were the rotors. The rest is just porting and port-matched the greddy header (+ polish). There was more stuff but that's all I really know so far.

XDEEDUBBX

i've got a really light foot..hahaha

Moostafa29

Haha, good luck.

lourx8

Alex, how many more miles until you break it in? I'm really interested to see how your set up turns out. It looks like we have the first low compression RX8s. I'm going with a 60-1 now. I keep forgetting to ask him what compression it is now at, but I think that the rotors are from a Turbo II if I am not mistaken.

Anyway, he is shooting to finish and put the car on the dyno on Thursday. He did send me one pic. The quality of pic is not great, but its something.