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-   -   C4 auto to 13b rew quick question (https://www.rx7club.com/rotary-drag-racing-167/c4-auto-13b-rew-quick-question-747178/)

rotorholic 09-05-08 04:27 PM

A 3 step is another rev limiter, you can adjust #1 for max rpm limit #2 for launch rpm limit and #3 for burn out rpm limit, can be used any order

tinmann55 09-06-08 05:48 AM


Originally Posted by Viking War Hammer (Post 8520206)
I had asked him about going with a 7" converter but he didn't know of a 7" core to use. So, we decided on a 8".

I emailed him back about the 4600 converter, wanted to know if it's going to lock up at 4700. So, we'll see what he says. I don't expect to get it right the first time.

Did you end up finding a buyer for your old setup?

7.5 you can get out of a jatco F3A Mazda GLC front wheel drive. 7 is harder to find, 2spd Toyota auto out of a 1970's model

Viking War Hammer 09-06-08 10:04 AM


Originally Posted by tinmann55 (Post 8529551)
7.5 you can get out of a jatco F3A Mazda GLC front wheel drive. 7 is harder to find, 2spd Toyota auto out of a 1970's model

Thanks. We're going to just do the 8 inch. It seems that will work just fine.

Viking War Hammer 09-06-08 10:07 AM

The converter guy is already testing mine. He's done the 5500 like I asked and it's going to max at about 6200 from what he sees.

Whatever that means? :scratch: :lol:

Busted7 09-06-08 11:36 AM

:icon_tup: Put it in already!:wallbash:

Nov is getting close and i want to see how that setup looks on the dyno :lol: it should have an interesting torque and h/p curve!:Wconfused

Viking War Hammer 09-06-08 03:22 PM

Alright, he's set my converter to brake stall to about 5000 and transbrake to 6200 with a 6200 stall.

What do you guys think?? :)

Viking War Hammer 09-08-08 06:59 PM

Hey Auto Guys............... what type of trans coolers are you running?

ultimatejay 09-08-08 10:36 PM


Originally Posted by Viking War Hammer (Post 8536167)
Hey Auto Guys............... what type of trans coolers are you running?

Who runs Auto's?? :lol: :lol:

Viking War Hammer 09-09-08 12:30 PM

Do you really want to get into this debate again?

rotaryengineering 09-09-08 02:46 PM

I bought some cheapy oil cooler at the local auto parts and it worked fine. My tranny guy said it was only a 1/4 mile so it would be fine. Sounds like your making good progress. It is actually pretty cool to put the boost down without having to shock the hell out of the tires between shifts. My car actually felt much more stable with the automatic compared to a stick trans. Breaking the tires loose past half track is some scary SH!T. I remember the owner of the local track telling me he was going to kick us out because we were sliding all over the track with a stick tranny.

Viking War Hammer 09-09-08 03:43 PM

3 Attachment(s)

Originally Posted by rotaryengineering (Post 8538954)
I bought some cheapy oil cooler at the local auto parts and it worked fine. My tranny guy said it was only a 1/4 mile so it would be fine. Sounds like your making good progress. It is actually pretty cool to put the boost down without having to shock the hell out of the tires between shifts. My car actually felt much more stable with the automatic compared to a stick trans. Breaking the tires loose past half track is some scary SH!T. I remember the owner of the local track telling me he was going to kick us out because we were sliding all over the track with a stick tranny.

Where did you mount the trans cooler? I'm debating whether to mount it under the car or build a ice box with a cooler inside. I won't be daily driving this car but would like to be able to make weekend cruises if possible. My main concern is heat.

Attachment 705085

Or,

Attachment 705086

Attachment 705087

ultimatejay 09-09-08 04:54 PM


Originally Posted by Viking War Hammer (Post 8538444)
Do you really want to get into this debate again?

Naw, just bustin your balls so you can hurry up and get this auto done. I wanta see how it turns out.

rotaryengineering 09-09-08 05:22 PM

I just installed the cooler a couple inches in front of the radiator with some steel braided lines. Nothing fancy like the pictures you posted.

13BT_Starlet 03-04-09 05:56 PM

Hey Viking War Hammer how are you coming along with your ride ? got it dyno yet?
Let's keep this thread alive , let me know how that C4 working out for you !

Gilbert

Viking War Hammer 03-26-09 10:50 AM

still haven't started on the c4. also, didn't get tuned yet. looking to get it tuned june 6-7 with the 5speed but won't make much power since I have a stock s4 block, probably only 350 hp or so. but, been busy cutting up the car

13BT_Starlet 03-26-09 07:03 PM


Originally Posted by Viking War Hammer (Post 9074043)
still haven't started on the c4. also, didn't get tuned yet. looking to get it tuned june 6-7 with the 5speed but won't make much power since I have a stock s4 block, probably only 350 hp or so. but, been busy cutting up the car

Bring that car down to Fl and get it tune , you should be able to squeeze 500hp out of that stock S4 . Post some pics up when you get a chance so we can see the progress

sk8world 04-09-09 03:49 PM

So 3-4k miles and my clutch is gone AGAIN! MAybe 20 launches on it. I was thinking sintered iron disk this time and add a scattershield but I keep coming back to the C4 idea. What scares me is seeing so many videos of guys having hard times getting it to launch with lack of TQ. I also street drive alot and do not want a 6800rpm stall on the street. So my question is:

Can I just do a C4 with a small stall (3500ish) and a brake. Would I be able to launch of the brake say 6-7k still? Why do guys run both? Is there ANYONE that has did a auto conversion in a 3rd gen that actually worked well? I have only scene one and its was bad....

So school me please!

13BT_Starlet 04-09-09 10:23 PM

Thats because the guys you seen on the video waited to load the converterwhile on the transbrake , here is a video I found and on board vid where you can see the tree and were he load on the brake and he cuts some excellent lights . Check out the second pass http://www.youtube.com/watch?v=nbJ1dBczphY

Viking War Hammer 08-14-09 07:26 PM

Has anyone else gone auto?

Looks like I'm going to start collecting parts again.

How safe would a 50-75 hit be just to get these up on the converters quick? Set it up to turn off when brake button is lifted.

K1HKSarse 08-15-09 08:20 AM

1 Attachment(s)
The saga goes on with my C4 13b set up.

My C4 was a Performance Auto top of the line tranny with their transbrake valve body. It has been upgraded by my tranny man here in the UK with transbraked billet valve body, kevlar band, some custom mods to improve performance and durability.
My converter was also wrong. The snout was too short which meant it wasnt supported by eccentric shaft, this kept burning out the bearings in the tranny.Also the stall and converter set up was way out. With 100bhp shot of gas on launch i could see 6200rpm and cut a 1.3 60ft, 10.1 @ 140mph so far.

I have a massive cooler mounted at the back of the car between chassis rails, it is ducted,has a massive 14" electric fan on it. I dont know exact size of it but can measure if necessary. I use Kendall ATF fluid.Once i fitted this i havent had any issues with temps and could go straight back to start line without letting it cool.Temps wouldnt go above 140f.

Attachment 705088

Video -

It took a few seconds to come up on converter. It stalled after burnout,was trying to restart it!!!!!!!!!!! AND i shifted twice after launch to 3rd by mistake,due to s***ting myself with my first ever wheel stand........listen for change back to 2nd. DUMB ASS!!!!!!!!!!!!!!!

http://www.youtube.com/watch?v=ojZA7iLBpV8

I have now ordered a new converter which is being made by Tony Dominello in Aussie, he has many years of C4,rotary combo experience and when researching the best person for the job his name came up everytime.Waiting on the converter to arrive and then we are back out testing.

I am going to pursue the auto route as its the best combo for what i want, i dont care about heads up, im just out for myself and improving my pb.I plan to push this set up to the 8's if possible.
My friend also runs a back halved FD with 13b and airshifted Lenco CS3 tranny, he has run an 8.8 @ 150+ mph, his goal is to improve his pb but to also be competative in class that he races in. We have both been through tranny problems and breakages with similar amounts of money involved to repair, major difference was initial cost. His was alot more that mine........

If i was to seriously consider heads up racing then i would change to clutchless 5 spd.Originally i went for auto due to cost but now i want to pursue it, i know once we get it right it will be good, quick and consistant.

Clutchless 5 spd is best route for all out drag car if you can afford it. I cannot comment on street driving as my car will never see the streets.

Will keep you updated.

mazda rx2 rotary 08-15-09 11:53 AM

nice K1HKSarse
 
i have found my favorite FD.i just set that picture as my wall paper.if i could have any rotary powered car it would be the FD.i will trade you my RX2 for your FD!!!!!what kind of fuel are you running?how heavy is your car?how much boost are you running?are you tuning your own car?with the MPH you have ran, the et should be about a 9.70's!!!!!1.30's 60 foot times are a kick in the ass.my best 60 foot time is a 1.306 with my C4 trans on the trans brake at 18 psi of boost no nitrous.:)

K1HKSarse 08-15-09 01:00 PM


Originally Posted by mazda rx2 rotary (Post 9428722)
i have found my favorite FD.i just set that picture as my wall paper.if i could have any rotary powered car it would be the FD.i will trade you my RX2 for your FD!!!!!what kind of fuel are you running?how heavy is your car?how much boost are you running?are you tuning your own car?with the MPH you have ran, the et should be about a 9.70's!!!!!1.30's 60 foot times are a kick in the ass.my best 60 foot time is a 1.306 with my C4 trans on the trans brake at 18 psi of boost no nitrous.:)

Fuel is VP Q16 116 RON

Car weighs 2450lbs with driver, i weigh 220lb. Still got approx 220-330lbs i could feasibly take out of car i reckon if i really go for it.

Boost at present is 20lb on a GT42R so not even efficient yet.......Still loads to come power wise.

Boost on launch is 17lb with transbrake and 100bhp shot of gas,6200rpm. Converter way wrong!!!!! New converter should see 6500-7000rpm on brake WITHOUT gas. I tried gas AND anti lag briefly but it caused excess heat build up and cracked housings around plug holes. At one point with gas and anti lag it came up on converter almost instantly and i saw 35psi!!!!!!!!!! I havent used it since.........

Tuning is done by myself and a friend of mine, was tuned by rotary shop prior to this here in UK, i use them as and when i have too still. Trying to get to grips with the tuning myself, my friend is very good with rotary tuning, really knows his s**t.

Viking War Hammer 08-17-09 12:48 PM

K1HKSarse, what are the specs on the converter you have now?

K1HKSarse 08-17-09 02:26 PM


Originally Posted by Viking War Hammer (Post 9432428)
K1HKSarse, what are the specs on the converter you have now?

Converter thats in the car now is a TCI item, 8" with a stall of 5000. Without gas i could only reach 3500rpm, launch was terrible.

Converters for rotaries are an art, they need to be done by people that know both. TCI do converters for mainly V8, if i had known the guy i got it from had gone to TCI i wouldnt of bought it.

Viking War Hammer 08-17-09 02:38 PM


Originally Posted by K1HKSarse (Post 9432676)
Converter thats in the car now is a TCI item, 8" with a stall of 5000. Without gas i could only reach 3500rpm, launch was terrible.

Converters for rotaries are an art, they need to be done by people that know both. TCI do converters for mainly V8, if i had known the guy i got it from had gone to TCI i wouldnt of bought it.

Can that converter be cut open and re-done?

What turbo do you have?


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