rb20 build!!!

[jholman]

This week we took on the dubious task of stroking and doing the build on a customers Rb20.

Its gonna make power.

[Jason@JGY]

We should have it apart later next week. I think we are going to stuff a rb26 crank in it and really increase the size of the motor.

[NathanM]

You guys get fun customers.

[jholman]

Cause we are fun guys thats why

[NathanM]

Anything cool going on here?

[Jason@JGY]

Anything cool going on here?

still a little secretive until we get further along

[NathanM]

Well then let's ask abstract questions.

Stroked RB20(26) vs. RB26; what are the differences going to be performance wise between the two.

Obviously the RB20 is much cheaper. You can buy the RB20DET motor, transmission, ecu & harness w/ maf included for only $1500 at JGY and an RB26 just the motor is $4200....

Why aren't people doing this all the time then?

[Logan@JGY]

hey guys we are getting to work on the RB build check out these pics we wil be keeping it updated frequently

http://www.jgy.cc/Project%20Cars/Andrew_Walters/Andrew_Walters.htm

[Jason@JGY]

up-date

73.7 stroke and 82 bore
It will be ruffly a 2.33L RB

pistons are on the way as well as the rods and bearings

[Jason@JGY]

some of the bearings are here

Josh is still short

[Jason@JGY]

What we are doing is using the RB26 crank in the RB20 block. Fitment is great. At first we wanted to go to an 88mm bore, there is plenty of room for it inbetween the cylinder walls...........but unfortunately, Nissan decided to make the water jackets and paths much larger on the RB20 versus the RB25 and RB26. Measuring as well as we could, we felt the 82mm was the safest/largest we could go without running the risk of making the cylinder walls too thin.

We are using the RB20 timing cover/oil pump because it is designed for the RB motor and the oil system is different..........the 26 would fit..........but using the 20 we felt was better.

It has never happened before.........but we could not get the belt gear off the crank shaft and had to ruin the oil pump to remove the crank from the motor to put the crank in the lathe to remove the gear.

So:

1 RB20DET
1 RB26DETT crank
6 RB20 pistons from JGY set up for RB26 stroke and RB26 rods
6 RB26 rods
1 RB20DET oil pump
1 RB26 crank bolt

[Jason@JGY]

We have finished the boring.

We are now working on the head...........valve job, guides, seals, cleaning.

[jdmsertom]

I've been working on a similar project for the last couple of years. Do you have any updates? What made you stick with the rb20 oil pump? Have you done a mock fit of the rotating assembly and if so how much clearance do the stock rb26 rods give you between the big end and the bottom of the bores? Did you do any oiling system work to the block while it was being bored?

[Jason@JGY]

Because I new the RB20 pump fit the motor and I wasn't sure if the rb26 would.

I haven't fit the rods in the motor yet.....if they hit, I'll grind the block........we do this often with rotating assemblies.

what type of oiling system work would you suggest?

[jdmsertom]

On my personal block I've done the Tomei restrictors(1.5 front and rear) and an external drain from the head to the sump. I've been debating whether or not to bore the oil drains that go strait from the head threw the block. I think you can go up to 9mm with them. I'll probably go ahead and clean the casting left overs out of the two big drains at the back before we assemble. Also going to be fabbing a big sump on the pan so it will hold at least 6.5 quarts. I plan on running a external pump in the future.

[Jason@JGY]

From what we have read, the Tomei restrictors seem to be more of an issue on the RB26 than the 20.

You plan on running an external oil pump on it? I wouldn't.

What does your shirt look like?

[jholman]

you thinking of an external electric oil pump? How much power are you looking to make on your build?

[jdmsertom]

I think the restrictors haven't been an issue with the 20 because not that many of them are making over what the 26 comes stock with. The external pump is going to be a belt driven unit. We're hoping for between 700 and 800. The builder/machinist doesn't think we'll have a problem getting there with the right turbo. And the shirt, it's awesome. Very colorful, lots of pinks and purples.

[Jason@JGY]

what engine management are you going to use?

[jdmsertom]

Not sure, it's been easier narrowing down what I'm not going to use than it has been picking a management system that I really like. I am leaning toward a Haltech unit but, Megasquirt and a unit my builder mentioned aren't out of the running yet. Also, I just read that article in Modified about Pro Stock Racing's r32 making 720hp with the stock tuned rb26 ecu. I think I need to look into that a little more.

[Jason@JGY]

what are you putting this motor into?

[jdmsertom]

what are you putting this motor into?
http://i279.photobucket.com/albums/kk160/jdmser/dcp_1346.jpg

[Jason@JGY]

thanks for the photo........that wheel seems to be popular with alot of cars that make their way into our facility

[jdmsertom]

Yeah, there weren't a lot of choices for the 4 lug cars. I've got a set of draglites for the back but, I'm not sure which rear end I'll end up with. With either the q45 or solid axle four point I'm sure I'll end up going to a five lug. At least in the back anyways.

[Jason@JGY]

yeah..........if you are building a true drag car......the solid axle would be best, along with a welded diff

[jholman]

9in ford FTW....

[jdmsertom]

I love the idea of a 9 inch Ford, especially because of all the support. The only thing is cost. The JUN auto drag rear member is about what it would cost for a half way decent 9 inch setup without all the welding. The other option is an 8.8 out of an Explorer. They're super cheap and can be upgrade to handle close to what the 9 inch will. You also get the bonus of the factory disc brakes. I also like for the car to have some street manors. I'd like to do drag week when it's all finished.

[jdmsertom]

any progress?