BosoMKII's project! 56k cut your head off

[BosoMKII]

I had one day of driving the car with few problems. ONE. And it was fantastic! All my hard work finally paying off, and my dream realized.

Then something new happened. I start the car and a HUGE cloud of white smoke billows out from the tail pipe! And now the engine won't idle, and generally doesn't feel right. Worse than before.

I didn't bother running another compression test. I decided the cylinder head just has too many issues, and I want to replace it.

So I found a replacement cylinder head (more on that later) and got to work pulling the old head. It's a lot of work to drain the oil, coolant, pull radiator, intake manifold, and everything else attached to the head!

Spark plugs. You can see the really cruddy plug with lots of oil fouling and water corrosion is cylinder #5, the problem cylinder.

 

[BosoMKII]

Everything removed, undoing head bolts.

Cylinder head off! Didn't even put up a fight.

Close ups of the cylinders. Bores don't show much of the hone marks, but they are still there. Cyl #4 had a score mark, but I couldn't feel it with my finger. Hopefully it's not an issue.

No signs of a blown head gasket so far as I can tell, but that doesn't mean anything. I may just not know what to look for.

Valves look dirty, but nothing is obviously wrong

EXCEPT THE MASSIVE GAPING HOLE

Well, there's my problem. If I only had one that is.

 

[Grandavi]

I got to where you were and threw in the towel. Had a built short block shipped for 2400 and head tested/rebuilt. My thinking was, when you are that deep in... Start fresh with a full rebuild.

Wasn't cheap, but I'm happy.

 

[IchibanEye]

Thats interesting...I thought the cressys where front sump? But yeah, thanks for the advice. If the 2M pan didn't fit, I was going to use a 7M pan, oil pump, and pickup from a Cressida. Dunno yet really. Just going to have to take stuff apart and see what works.

Thanks for all the compliments guys! This is a really fun project so far.


And this just in!! My wheels arrived today!! My brother just sent photos ( I am at work )

The specs are 15x8 zero offset. As soon as I do a test fit with tires I will know how much I can lower it. Going to go for a "nice" drop. Not too slammed, but defininatly low.

That is a good looking wheel.

 

[BosoMKII]

I got to where you were and threw in the towel. Had a built short block shipped for 2400 and head tested/rebuilt. My thinking was, when you are that deep in... Start fresh with a full rebuild.

Wasn't cheap, but I'm happy.

I wish I had that kind of cash to spare! That would be the best route to go, but I don't think worth while for a non-turbo 7M

 

[BosoMKII]

That is a good looking wheel.

Thank you. The wheels are long gone however. They went with my Datsun Z when I sold it.

 

[BosoMKII]

Earlier I alluded to finding a replacement cylinder head.

I was at Performance Options in Oakland the other week and asked what was under the tarp in the back corner:

Performance Options had a customer bring in a Supra with a recently rebuilt engine that had slight rod knock. Instead of repairing the engine, they just swapped a 1JZ in. The fresh 7M just sat there until I came along.

]

I struck a deal with the shop and pulled the cylinder head so I could just swap onto my existing block without having to pull the whole engine or have to rebuild the current cylinder head. Easy fix!

I also got ALL the accessories to the engine. Intake manifold, sensors, ECU and harness, 3 inch downpipe, rebuilt turbo. Everything.

Oh, did I mention this is a 7M-GTE?

:tu:

 

[Grandavi]

Sweet find!

 

[BosoMKII]

Sweet find!

Thanks! I'm amped. Get to start work soon now that these just showed up:

 

[BosoMKII]

The intercooler pictured earlier was me being impulsive. First, it's one of those cheap eBay intercoolers. It weighs a ton and is painted. I'd be surprised if it's actually aluminum. Second, it doesn't fit. Too big for the space I've got to work with.

So I searched around and found a stock Mazdaspeed MX-5 intercooler for $45. It's small at 8x8x3, but will likely cool better than the bigger, lower quality flea bay unit.

Progress has been slow as I've been busy, but mostly smooth. Then disaster struck! I dropped a bolt, a spring, then another bolt down into the timing cover. :evil:

In order to remove, the crank pulley bolt needs to come off. This is no easy task. I need to figure a way to keep the engine from turning in order to break the massive 195 lbs-ft of torque bolt.

Other progress has been going well. I forgot that the 7M-GE block doesn't have oil fittings pre-drilled. So I ordered an oil line kit from Drift Motion specifically designed for this conversion.

Test fitted the turbo. Not sure the down pipe will clear. Harness in.

 

[BosoMKII]

Making a little progress here and there. Right now I am trying to learn all the new components and layout, and working to figure a few things out.

One issue is that the EGR valve now interferes with the throttle pedal arm as it exits the firewall. So I either lose the EGR (bad for cylinder temps and emissions) or convert to throttle cable. I'm leaning towards converting to throttle cable, as even without the EGR the turbo throttle body is in an inconvenient place and makes rigging linkages difficult. Not sure exactly how I'll manage the conversion.

Another issue is how fast I'm running out of space in the engine bay. The intake tube puts the air flow meter right up against the sheet metal with no room for an air filter. I don't know if shortening/changing the air intake tube geometry will upset AFM readings.

Intercooler piping will actually be pretty straight forward. The factory intake pipe is in a good location. The turbo to intercooler pipe needs to be made.

The downpipe also doesn't clear the steering arm. Looks like that will be an easy fix for the shop though.

 

[Grandavi]

The deciding factor for the EGR delete for me was its location and the fact it's unmonitored. The emissions aren't a concern where I live due to our not having to do emission tests.

As for decreased heat in the exhaust, im not sure that is enough of a factor to really consider for a 7M really. I'm not sure that 100 degrees at WOT would be noticeable realistically.

 

[BosoMKII]

Thanks for the advice!

Know anything about the AFM placement? How critical is the accordion hose to accurate readings?

 

[Grandavi]

Not sure what you mean. The AFM shouldn't care about anything behind it.
The accordian hose just has to be between the AFM and the turbo. (As long as it's not kinked or cracked)
Not many options in that area though.

 

[BosoMKII]

Thanks for the reply.

What I mean to ask is, if I were to shorten the accordion hose or make a custom air intake tube, will doing so upset the AFM readings?

 

[BosoMKII]

Not much to report lately. Been super busy with life and not working on the car much, save for here and there.

Plumed oil lines and oil cooler, and made intercooler pipes. I went to Performance Options and scrounged in their spare parts area and made all my pipes with couplers for $60.

My car is put together with so much hardware store stuff and random parts it's starting to look like a pirate ship. Whatever, so long as it works properly.

Tried to start the car yesterday, but it just catches briefly then dies. Will need to wire up the check engine light to see what codes come up, and go from there.

 

[black ice mike]

This thread is awesome!!! I spent most of class reading it and just finished so now that you have the turbo and everything what kind of power are you looking to make?

 

[BosoMKII]

Thanks!

First goal is for the engine to run like stock, and be reliable as a factory car.

After that, 300 wheel horsepower is totally attainable.

That is a long way off however....

 

[Grandavi]

From my supra journey... The most fun is a ct26 upgrade running 300-350 at the wheels. Quick pulls and a lot of "yeehaw!".
Huge power usually trades some of the fun with later more powerful pulls, but the fun factor is a bit less because you gotta be a lot better controlled. More focus on safety...

 

[BosoMKII]

Grandavi,

No experience with the 7M making that kind of power, but I suspect I will agree with you 100%.

I drove a 400whp, 1st gen RX-7 once, and it was just like you say. Big lag, then the power would just explode and spin the wheels.

Certainly entertaining, but sketch. Not useful unless you're pointed totally straight either.

For a street car, readily accessible torque is key.

And hella fun