EpitrochoidalPower!

Ok I drive a 1985 Rx-7 fb. For the past few months I have been working on this project heres a list of what ive done.

Engine: 13b Series 4 Turbo (with turbo bits removed). Means its a 4 port

-Complete rebuild
-Bridgeported
-carbon apex seals
-racing apex seal springs
-bearings windowed and oil pressure increased
-omp removed running premix

Intake:

-EFI Hardware 50mm ITB's
-IDA intake manifold

Fueling

- 4 x 550cc Injectors (from the turbo 13b)
- Seriously big bosch fuel pump drawing fuel from a 1.5 L surge tank
- 2 lift pumps in the tank supplying fuel to surge tank
- Rising rate FPR

Fuel Control

- Megasquirt 2 (v3) ECU running ms2/extra code

Other

- Front mounted 13b Oil cooler
- Very nice, very lightweight flywheel
- Falken Azenis tyres

Just got her running the other day. Sounds very very good. Im just waiting on some brake pads before I start driving her (they will be here next week). I will try break her in as soon as possible and then I will be taking her to the dyno . Will definitely post the results for you guys. I guess we will have to wait and see how much rwhp she puts out but im thinking quite a lot .

Some pics of the setup:

The throttle bodies:



The Flywheel



The bridgeports (before the irons were lapped)





The Engine



The exhaust ports - left is before polishing, right is after



The engine in the car (this was before completion and wiring)





I hope you enjoy them. Ill be taking a vid soon of the car running which ill post up here.

Cheers

CJarrett

Looks awesome, where is the throttle bodies from?

Kyrasis6

You sure there is enough beef in those bridges for them to stay together? They look awfully thin to me.

EpitrochoidalPower!

Well lets hope so . The guy who did my engine has built a lot of engines and used to race. He drives a 13b peripheral port in a small mazda pickup and a 13b bridgeported Capella. And ive seen plenty of other cars around my area with his work and theyre all running strong. If something does go wrong im sure he will help me sort it out.

Oh and the throttle bodies are from www.tweakit.net

My brake pads are arriving tomorrow so i should be on the road this weekend.

Tom93R1

iTrader: (2)

Thats alot of fuel for a non-turbo application, do you have plans to add a turbo at some point? pretty cool project, I like the ITB's

BASTARD

iTrader: (4)

I think those bridges will last long enough... I have seen much thinner

joeylyrech

iTrader: (11)

I like the main port,but it doesnt look like is a lot of support for the seals on the bridge,good look with the project and looking forward for a video

AlexG13B

iTrader: (7)

ports look really big..

joeylyrech

iTrader: (11)

did you use a NA center plate?i ask cause you have the NA filler neck,hold on cant be NA it does not have a egr valve,okay im confused now,what year center plate is that?

EpitrochoidalPower!

Im not sure of the year. Its from a series 4 turbo if that helps.

EpitrochoidalPower!

Oh wait yeah I replaced the filler neck with a NA one. I think the neck is from a 12A. But yeah the center plate is from the turbo motor.

dj55b

iTrader: (2)

I can't wait to see the results neither, I think you're the only guy beside me that i also a good full review on ITB's. As for what tom93r1 said about alot of fuel I have to agree (whats you injector sizes?) I'm using just 2 720cc Venom injectors, and at around 7k rpm I'm only at about 65% duty cycle or something like that and hitting about 11.5 AFR, running about 45psi on the fuel pressure regulator.

EpitrochoidalPower!

I'm using four 550cc injectors. Yes its probably overkill but I got them with the engine so it made sense. I got the brake pads finally. Had some trouble getting them on the rears. Left rear caliper had seized had to get it in a vice and heat it up to get it apart. But it all worked out in the end. Took it for a drive up the road and it definitely needs a lot of tuning. Bucks and coughs when trying to get moving and smokes a lot. So I turned it around as soon as I could and parked it. I havent had any time this weekend to do anything more had a 21st to go to and friends and GF have been keeping me busy. So hopefully tomorrow I can get some fuel in her and start driving around and tuning with my twin brother. I'll get some videos when I do so. She sounds really really good. Probably too loud for the street but who cares? I didnt mention earlier i'm running a 3 inch exhaust with some locally made up exhaust manifold. I have noticed that the local track is having some friday night street car drags and an open track day next month. Lets hope I have the car tuned and broken in by then so I can see how it goes on the quartermile, and ive always wanted to get out on a circuit. I was talking to my engine builder and he showed me some dyno graphs of some previous engines that he has built. Showed me a 12A bridgeport with 169rwkw which is 226rwhp, which would be roughly 264hp at the flywheel!! Thats with a weber IDA. Also saw a series 4 turbo (like mine) which had been converted to NA and J-ported. Was putting out 175rwkw which is 235rwhp (roughly 275hp at the flywheel) even with the low comp rotors (goes to show compression isn't as important with rotaries as with boingers, NA anyway). From his experience with other engines he has built his estimate on my engine is 170rwkw (227rwhp or ~266hp at flywheel). However he is a carb guy so that estimate is on a weber IDA so maybe ill get some extra ponies with the ITB setup. Well thats only an estimate so im not going to get my hopes up too much. Id rather be estimating too low not too high . However it turns out its still going to be fast in my little 1st gen. I cant wait to open her up and scare the %@$! out of myself

blackedoutFC3S

iTrader: (7)

dude that is an awesome setup man! i noticed you havent updated this in awhile, is she running good no and do you have any of those vids?

EpitrochoidalPower!

Hey

Sorry about that yes she was running and driving, was busy tuning her. With the lighwieght flywheel and bridgeport she was a bit of a handful at very low revs/speeds but that was to be expected. Im sure with some tuning I can reduce that. Problem was that while i was driving one of the oil hoses blew off my oil cooler. I dont think ive done any damage just havent got around to changing out the oil hoses/fittings yet. Will post update when i have done so. If ive done some damage I should be able to get some rotors, e-shaft etc from engine builder quite cheap but lets hope it doesnt come to that.

NOPR

You need to dyno it! I'm curious what an N/A bridgeport like this will make compared to some of the sideport N/A's I've seen.

EpitrochoidalPower!

here are two vids...they arent great and sound is bad. Will borrow brothers camera and get some better ones.

http://www.youtube.com/watch?v=qhrIbz0_1cY

http://www.youtube.com/watch?v=kNpdvNXK6PY

yomo

it sounds sexy

cant wait to see what it puts down on the dyno and the track!

RotaryPicha

iTrader: (2)

Sounds great, if I did a half bridge do you think it would sound a lil like that. Might be worth going full bridge. sound Nice though

EpitrochoidalPower!

Took the car for a drive/tuning session yesterday. Found the car was running far too lean, richened my map up a lot and now its running much better. Was awesome driving the car again, even if it can be a handful at low revs and in traffic. If I put my foot down a little I could feel how the engine just wanted to go. I had to restrain myself as I have a long way to go before the engine is broken in. Water temps stay low, oil pressure is nice and high. Went through the logs yesterday and nothing looks strange so it seems im on my way. Now I just need to get a 1000km's through the car and then im going to the dyno to tune for power and at high revs. I want to make use of their wideband 02 sensor to make sure I dont do any damage when im revving high (9500rpm...). Wideband sensors are seriously overpriced here which is why im not using one, at normal driving tuning with the narrowband and by feel is working fine. Timing is also much better now and i've got the idle lower and more stable (brap brap brap stable i mean ). Hopefully I can get the engine broken in asap so I can post dyno figures. If i can afford the gas . Must also get some better videos up, perhaps some videos of driving. And ill make sure to record the dyno runs.

dj55b

iTrader: (2)

Out of curiosity what AFR are you tunning it too and what timing are you running?

EpitrochoidalPower!

Must still do some research on best AFR for my setup. Im planning on just tuning for what feels/sounds best and keep checking on power figures while using the wideband sensor to make sure im not running on the lean side for safety reasons. Im not sure on my timing, will ask my engine builder because im using a dizzy so I just set the timing using a timing light to the marks which my engine builder marked off when he built the engine. He had the marks set to where he wanted the timing after the mechanical advance had kicked in so i had to rev the car until it advanced fully and then adjust the dizzy so that it was where he wanted it. I retarded it a tiny bit after that just to make sure i dont get any knocking and will start adjusting it more once car is on dyno. He uses same dizzy setup on his peripheral port and its working very well. Ive also seen the dyno charts of some of his customers engines that still use dizzy setup. Was a j-port 13b with 240rwhp and a bridge-port 12A with 226rwhp so they are definitely putting out good power. I must still convince him to get his p-port on the dyno. Anyway, getting a hold of second gen ignition here is impossible and isnt it supposed to give problems at very high revs? Although I here there is a mod now which fixes that. I would love proper ignition control so maybe in the future ill find somone to send me some second gen direct fire coils but for the moment ive got my hands full just tuning the fueling .

By the way Dj55bb hows that sexy 12A FB of yours going. Was sorry to hear that you blew your rear rotor. Is it back on the road yet? Im still in awe at the wiring job you did and I would kill for that carputer.

EpitrochoidalPower!

Ok...I recently installed my LC-1 wideband 02 sensor and it made tuning a breeze. Seeing as the car was running well I went for a long drive and finished off the break-in. Went yesterday and opened her up and WOW. Car is very very fast, and in the upper rpms my AFR's were still as low as 10.6 so theres still more power to be gained. A few more WOT logs and some VE analysing in Megalogviewer and im sure i'll pull even more power, not that I really need any more. Its pulls hard from 3000pm all the way up to 9500rpm. In first gear it hits limiter very quickly and gives some serious stomach wrenching acceleration through every gear. 100mph comes up rather quickly . Also need to tune my acceleration enrichment as engine gives a little choke when you suddenly apply throttle, but it overcomes that almost instantly and then things get fun. Im extremely happy and relieved after all the hours and hard work i've put into this thing shes finally running like a champ. Will start getting the AFR's up to more reasonable values like 12.5 and perhaps up to 13.5 - 13.7 at WOT as recommended by some people on the megasquirt section. Wont jump straight there though, would rather get a feel for what works well with this engine. Once thats done I must just find some money and get the car on the dyno. I know my current header isnt great but I thought id get a dyno run in before I get a new one made just so I can see the difference.

I have a short vid which I will get up soon and ill try take some others ASAP.

-xlr8planet-

iTrader: (3)

Congrats man

EpitrochoidalPower!

Heres the vid. He pulls away slowly and only hits the gas once hes gone past the camera and his shift into second isnt very good. I had a much better run straight after him which really kicked but typically my friend wasn't recording . Sorry about the quality i'll take some good vids once i've finished tuning.

http://video.google.com/videoplay?do...76231801086888