1600 turbo build thread

[buguy]

I had it on the lift still so I put it back in the air for a better look at the leak. Can't tell much from the pic but it looks like it's running down and around the cylinder near the head. Can't really leak oil from between the cylinder and the head so it almost had to be coming from above. Only thing that's weird is the last pic I posted you can see the oil is black as night and I had JUST changed the oil minutes before that. So that's kind of throwing me a curve ball. Unless it's picking up soot that is on the cylinder before dropping on the ground.

[Chip Birks]

Didn't split a cylinder did you?

[buguy]

I don't think so. I just did a compression check recently and everything looked good.

[rubenski]

Didn't split a cylinder did you?

Cylinder failliur was my frist guess too

[buguy]

I will do a compression test again and see what I get.

[madmike]

didn't u just re-torque them heads?

[buguy]

Yeah. But I did the compression test after that.

[buguy]

I've only put maybe 4 miles on it since I've been back with it.

[madmike]

just looks like 'seeping' to me? push rod tubes are dry looking.
Is it leaving big puddles? Mine leaks on the sump plate and a tablespoon of oil on concrete spreads out to look like a 'Gallion'

[buguy]

Well it's not a ton, but it's too much for me to take.
Also I picked up a 2 barrel adaptor the other night. Found it cheap. So I bolted on the Holley 500 cfm 2 barrel last night. It was pig rich right from the get go. I didn't look in the carb. I pulled the bowl off to put my jets in, but that's it. Didn't even look at it. I might go through it this weekend. Or maybe I wont. Just trying to get it running the best I can 'til I go efi.

[theKbStockpiler]

Are you able to set the idle screws by turning them out until you get the highest speed? I have read where SU's work okay but from tuning 4160's I can't fathom how a huge carb could work on a small engine with a big induction and hence a weak vacuum signal.

[buguy]

Well the idle screws work well on the primary side. I have a Holley HP series carb and has the 4 corner idle screws. The secondary side idle screws don't seem to do much. This is one of those 390 cfm carbs that is mostly used by roundy round race guys as a restrictor. I have a feeling there has been some modifications done to it so I really don't know how a stock one would work. The damn thing runs pretty good though. As far as carbs go, this one is about as adjustable as you can get. 2 metering blocks, 4 corner idle, 2 accel pumps, 2 power valves, and high and low speed air bleeds on both primary and secondary sides.
I did pick up a used 500 cfm 2 barrel the other day and a 4 bbl to 2 bbl adaptor. I put the carb on without going through it. I think the power valve was blown out because it was pig rich and the idle screws did nothing. I put a new power valve in it yesterday and new gaskets. Cleaned everything and went through the fuel valves and such. Gonna throw it on today to see how it likes it now.

[theKbStockpiler]

With out doing a lot of analysis, the secondary idle gets have to be able to go from rich to lean or the circuit can't be evaluated in my opinion.

I would jet the power valve restrictors (jets) way down so I could positively tell how the main jets were working. I also have to think a spread bore carb has to work better unless wide open hp is the main goal.

[buguy]

I agree. But they don't make small spread bore carbs.
But really I have it running pretty good already. It took a big accel pump shot to really make it run well. I am still going to try the 2 barrel since I have it though.
I have 3 of the 390 cfm carbs and one that is a 450 cfm. They all work pretty well.
Also none of the carbs I have have restrictor jets. They are all just ports. I could drill and tap them for jets but I don't really don't want to bother since I'm gathering info/parts to go efi.

[theKbStockpiler]

I'm positive Edlebrock makes a 550 or maybe a 525 CFM. With a 4160 you have to install metering blocks to jet the power valve. Otherwise you just have the lousy metering plate or whatever it's called.