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Thread: RE4F03B Automatic with shift kit and Turbo = Success!

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Posts: 51-60 of 118
2015-05-21 14:40:00
All done! Mileage is at 146,088. It takes the 71mm a lot longer to spin up compared to the 54mm BBT25, but I like it coming on gradual and should make it pretty easy to tune. I also made up a digital oil and fuel pressure gauge for the center/driver side vent. We really want to watch the fuel pressure under boost now that we will be holding a constant 13+ PSI and have the stock fuel pump in. With the old setup we were almost maxing the secondary 440cc's and shouldn't have been. So we are guessing the pump can't deliver the fuel pressure because of pump size and maybe voltage drop from the factory wiring. I already have a GS342 and 12ga wire ready if it is the problem, just curious how much the stock fuel system is capable of. Another gauge setup we will probably make for the other vent on pass side will be trans temp and trans line pressure so we can monitor the automatic. I'm sure this one will let loose soon so we can put the new rebuilt one in and see what kind of miles we can put on a trans with new clutches and shift kit. Also working on a RE4F04B/V build for the cars if the RE4F03B can't hold up. If you aren't familiar with that trans it comes in the 6 cylinder Nissan/Infiniti cars and the turbo VET Xtrail.

Last edited by Y2KG20 on 2015-05-21 at 14-51-46.
2015-05-21 15:17:59
Originally Posted by Y2KG20
Also working on a RE4F04B/V build for the cars if the RE4F03B can't hold up. If you aren't familiar with that trans it comes in the 6 cylinder Nissan/Infiniti cars and the turbo VET Xtrail.

Will the bell housing from the RE4F03B swap to the RE4F04B case? I have always suspected it may fit, but have not had a chance to compare the bits side by side.
2015-05-21 15:25:21
You have to use a VET automatic for the bell. Then get creative for axles and axle seal for pass side after removing AWD gearbox. Then if you want to get crazy grab a I30T VLSD to stick in it.
Last edited by Y2KG20 on 2015-05-21 at 15-26-30.
2015-05-29 15:04:53
We got everything together and finished last weekend. I installed a new felpro oring on the distributor since it was the only leak left to fix on the car. We set the timing real quick and went out to tune it. The car was flat out haulin' and felt awesome @ 14psi while we were tuning. Then coming off a ramp to the highway it went to shift and pop pop.... Was missing real bad and had to limp it home. Pulled into the garage and listened to it running really rough and misfiring really bad but no knocking. Pulled the plugs and found this on cylinder 2 and 4:

Looks like the balancer spun and we had the timing (guessing by physical TDC and marks) about 10 degrees advanced. So this is what happens @ 14psi / 25 degrees base pulling 1 degree per PSI boost on 6 series plugs. The detonation actually shut the gap on the plugs so they wouldn't fire (picture after I pried the gap back open) also started to melt the straps and that's why it was missing. We are pretty lucky we aren't putting another motor in. It passed a compression check and I have BKR7E's in it now and backed roughly 10 degrees from the distributor then drove it about 220 miles so it looks like everything is ok. Time to pull the balancer and get it timed right
Last edited by Y2KG20 on 2015-05-29 at 15-08-31.
2015-06-17 05:18:34
Awesome set up
2015-06-17 13:20:58
Well the update on the timing didn't turn out to be a balancer. We really didn't get it figured out. When we put this car together all that was done was Patch up the front end, slap the turbo kit on, install the shift kit, installed a Fic6, and put better plugs in it. I didn't check anything I didn't have to because I really had no idea it would run this long. So I never checked the timing figuring this was a one owner old lady car that still had all factory Nissan stuff on it.

Now back to me changing the distributor Oring weeks back after the T28 install to fix the only leak left on the car. Put the distributor back in and timed it. I knew the distributor looked to be in the wrong place after setting it to 15 degrees but we were in a rush and didn't think anything of it. Boom Boom and were back in the garage. We ended up pulling the valve cover and balancer to check it over. The balancer matched up to 3 others dead on. We counted the chain links and matched up the cam gear marks and positions with the crank. It all lined up right but the balancer timing marks and distributor placement didn't line up. When I put the distributor in the exact position as my girls 00' B15 dist it is 10 degrees off. I also have another stock RR engine sitting and it's distributor is also set in the middle like the B15. I'm probably just confusing anyone reading this mess but what it comes down to is that I know where the distributor should be for 15 degrees locked timing mode so I put it there. If I put the distributor where the balancer shows 15 degrees it's actually advanced 10 degrees and melts plugs and does all sorts of fun stuff.

So I am leaving it where I know it should be and it runs out great but just doesn't show correctly on the balancer. I'll probably loose sleep every night until I tear the engine apart but oh well I figure the car can't last forever and when it finally goes I can figure it out then.
Last edited by Y2KG20 on 2015-06-17 at 13-25-13.
2015-06-17 13:28:14
Such an odd issue. Is it a factory stock distributor, or does it look like it might be an aftermarket replacement?

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2015-06-17 15:04:46
We thought of that and compared it to the other 2 engines we have and they were exactly the same. Everything on this car is stock and pretty sure it was always maintained at the dealership so no aftermarket stuff. Things we thought could happen from the wreck is timing chain jumped from shock, balancer spun, damaged distributor, or even the ECU.... It makes a lot of sense if the chain skipped a tooth being 10 degrees off but we pulled the valve cover and counted the links both ways several times and we are 99% sure it's right... I guess we won't know until I blow it up and we can inspect the engine when it's out. For now it's set right by the distributor placement, runs great, Plugs look clean, and just got 26 MPG mixed mileage. It just shows 5 degrees timing on the balancer when in locked timing mode??

Anyway the car is at 12,000 miles and has had the 71mm turbo on it for about 1,000 now. 14psi is a little too much for the old transmission, if you don't have the pedal floored so you get 100% line pressure from the TPS it will slip / slide in to gear too slow and hit the rev limiter under 14psi. I have to be careful not to pedal it under full boost while shifting. Right now I am just lift shifting so I don't take the clutches out. We are working on a few things to combat this issue. #1 a device to rescale the TPS signal to TCM so you can have 100% line pressure as early as you set it. #2 replacing the TCM with a fully manual shift control. JamesJV0 is finishing up the code for the controller so we should be testing that soon. Once we get the ManuMatic controller working right we will incorporate automatic shifting control mode which will take a lot of tweaking to make sure it's safe to shift on it's own. Another thing we will have to work out is the ECU throwing a code when the TCM is disconnected, just a annoyance but something that needs to be worked out to make it codeless. We could simply use a manual ECU but that would be cheating

So far I think the T25BB turbo is totally safe on a shift kitted RE4F03B. Even when we turned up the boost with the T25 it would start to run out of steam and fall off before the shift so it worked really well and think a rebuilt or excellent low mileage RE4F03B(V) would last a very long time. The only way I think you could run into problems with the T25 and auto would be if you have a boost controller that allows you to force up the boost in the areas that drop off.
Last edited by Y2KG20 on 2015-06-17 at 15-07-15.
2015-06-17 15:17:58
Awesome project. Great results. Auto g20s are very plentiful here with a t25bb would make fun little grocery getting/commuter

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2015-07-07 14:47:36
Well the motor is knocking on heaven's door now... At least I get to tear it apart now and find out the weird timing issue. I have several RR's laying around so it's no big deal to get her back on the road. I'm going to throw the rebuilt Re4f03B that we changed the frictions, band, and shift kitted while we are changing out the motor. So I guess this is the end of the 1st automatic tranny test due to engine failure. I'm going to take the tranny apart and freshen it up with new stuff and maybe a LSD from another parts car so I still have a spare laying around for the next time I blow something up

So : Over 12k miles and over 1 year of abuse @ up to 14psi with no failures on original transmission with just a shift kit. I wouldn't suggest over 9psi on factory TCU and friction discs.
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