legacycentral bbs

So,
The engine is built. It is a pretty straightforward build, but we did hit a few snags using some of the EJ20G JDM parts. We used the Ej22T head gaskets. The coolant passages on the 20G and 22T are identical. We went with the 22's because they were cheaper. I see the bore difference as a non-issue. Guy have been using Ej25 gaskets w/25 heads on 22's for some time.

The hang ups occurred when trying to use the EJ20G up-pipe and turbo. The bracket for the up-pipe drops down about 10mm and will not mount to the EJ22T heads. But if you use an EJ22T up-pipe this is a non issue. Because it was the only VF-10 I had that was in good shape, we had to switch it over to the USDM uppipe. This involved cutting a rusted bolt off the EJ20G uppipe.

Problem #2, the EJ20G Vf-10 on the compressor side where it feeds to the manifold is clocked about 10 degrees differently than the USDM. We are going to run a custom silicone pipe off the turbo to the back end of the stock intake, that we are going to cut short and still mate up to the throttle body.

The last trick was the coolant lines. The JDM engine places the turbo coolant box on the passenger side. The pair of lines interferes with dipstick. We just cut the bracket a little bit to make it clear the lines. Again, if you use a stock USDM coolant tank and lines, this is a non-issue.

This engine should be in the car next week. It is using all stock exhaust manifolds and down pipe. etc. For the short term, we are going to run it non-intercooled, on a stock 1.8l on wastegate boost. Should be a fun little car. I never ran the hard numbers, but I think we are in the ballpark of 9.5:1 CR. Should be a beastily little ride...

Sweet, cant wait to hear the results. Are the pistons in the 20G forged?

Matt- Does this mean that the EJ20G heads will swap over to the EJ22T as a direct swap, without issue, and all the coolant passages and everything line up perfect?

ej20g are forged piston and closed deck.

Heh heh, same question as Matt.

Steve

arent the 20 g heads doch???? or are the ones that came off you block older models

Good to see the frankenmotor working out for you.

The only known issues with using the ej20g heads is the head volume is huge, (I saw the heads this weekend and the ports are massive) therefore the cp ratio will be around 7:1. Only other thing is the electronics.

engine management and a thin head gasket solve these problems.

Matt will be able to tell you much more then me.


Matt
I need to switch the clusters. I'll post a thread about the issues.

Yes,
The Ej20G heads will line up perfectly with the Ej22T block as far as coolant passages are concerned. Yes, they are DOHC. And no, the EJ20G pistons are not forged. They are cast moly coated pistons just like the Ej22T. Only STi's have ever had forged pistons from the factory. As for the CR? I personally don't see it as a problem like some other people do. I know a couple of guys that run around with EJ22T blocks with EJ25 heads running 7.3:1. Porsche historically has gone as low as 6.5:1 CR on their turbo cars. Low CR is not as big an issue as many people make it out to be.


tdgkorn,
We will be there again on Saturday if you want to come by and pull the cluster from the '93. Or, if that is too much of a PITA, I can just give you your $$$ back...

I didn't think the pistons were forged. Forged pistons in street cars are very rare. They can make emissions standards harder to meet as well as making noises when cold that the average person would be alarmed or annoyed by.

Steve

isnt really big head volume a good thing. as in really good flow and more hp. also if the comp ratio is low doesnt that mean more boost for motor.

Flow is a function of cams, intake/exhaust valve size, port shape/size, and combustion chamber shape, not volume.

You can run more boost in a low CR engine with less risk of detonation compared to the same engine with a higher CR. So sort of - it's safer.

Steve

ahh i finally found your thread. i found out that the ej20g motor ive been lookin at is a legacy/liberty ej20g. anyway im going to be doing the exact same thing pretty much... except im usin the vf11.

yea those ej20g heads are HUGE! im gonna slap those on the ej22t when it gets rebuilt... thanks for the thread man. this is all i needed! time for boost!

tee hee