88 Turbo Old Man Project Car

[GrimJack]

I've never broken a rod, so stock there is fine.

However, I've blown up quite a few stock pistons, so the cost difference there is worth it IMO. I know you *can* build a stock block to take 500+ whp, Adam has done it... but seriously, the cost difference is what, about $300? That's less than 5% of the value of a Supra in good shape, which is where I think he's headed.

 

[HommerSimpson]

I think Jack was saying that if you have to bore it and buy NEW pistons then by all means cough up the extra at this point in the game.. if he did not need to bore then stock or nprs or = good for the 400hp

I think thats what jack ment :}

if i had bored mine i would have went forged... next block i build will have forged

 

[IJ.]

Here is the number I found on the block once I removed some dirt and oil. They were located at the top fron on the exhaust side. It says '304' and appears to be held on with a screw. Anybody know what this indicates? If not, I'll post a question in a seperate thread.

Not sure if "304" is a date or a foundry marking.

My bud's early 87 is "328", my new 93 block has 5 numbers so I'm guessing it's DoM.

 

[starscream5000]

Here are the pics of the head. Took som more today. Measured the head thickness and got 116.5. So I can only assume that not much has been taken off of the head. I mentioned earlier that the original MHG measured 1.5mm at the beads. So, I'll look for something a little thicker and have the block and head milled appropriately.

That's odd... IIRC stock height is 116 even, you sure there wasn't some debris on the surfaces where you were measuring?

sounds like that head is untouched as far as even being resurfaced. Get it hardness tested first.

 

[supradad]

That's odd... IIRC stock height is 116 even, you sure there wasn't some debris on the surfaces where you were measuring?

sounds like that head is untouched as far as even being resurfaced. Get it hardness tested first.

I cleaned it off. I was using digital calipers, not a micrometer. I couldn't measure it in the middle, just the front. Since it was slightly larger than stock thickness, I assumed it had not been machined. Maybe that's why it wasn't running correctly.

What is involved with hardness testing, and what are the specs?

 

[p5150]

I wrote this up a couple of years ago:

http://www.supramania.com/forums/showthread.php?t=276

And here is a link to calculate your compression ratio before you purchase a head gasket: http://www.csgnetwork.com/compcalc.html

 

[supradad]

Gentlemen, thanks for all of the feedback and opinions.

I wasn't clear earlier regarding the crank. When I bought the car, the owner had bought it from a friend. Both could not fix the oil leak they thought was coming from around the crank. When I looked at the car, they already had the belts and balancer off. You could see where the balancer had slipped forward and the keyway chewed up the crank when it slipped forward. I took some more pic's tonight. The keyway push up the sides of the crank towards the passanger side, and had slipped front. The lip was high enough that I could not remove the gear. I had to grind the lip down to get the gear off. Anyway, my thought was that the front crank bearing and thrust washer was shot, the front possibly bent. I was thinking it all needed to be replaced when I bought the car.

So, I have a crank and bearings coming from Standard Crankshaft Company.
I already have ARP head boolts
I have a manual boost controller
I have exhaust stud helicoil kit on order
I have the freeze plugs and Oil shaft bearings coming from Toyota today
Water Pump is coming
I need to price a good oil pump

I am thinking of waiting to have the block looked at before I order the pistons, if I go that route. A quick check on-line tonight yielded this;
Driftmotion JE pistonns $820
Driftmotion Probe pistons $395
E-bay JE pistons and Eagle rods for $1050

If you bore 20 over, do you use the 84mm gasket?

If I'm going to make the jump, I think I'll just go all the way. I am not sure what abuse this engine has seen, but I am sure it wasn't taken care of. This way I'll know it's good to go.

GrimJack. I like your recommendations. I saw today that someone mentioned you can hit over 400hhp with the stock injectors. I was trying to go the easy route w/o all of the electronics. I will push off the exhaust until the car is roadworthy. Once satisfied, I'll go for the exhaust. Then when I have no money, and the wife doesn't like the color, I'll swing a paintjob!.

 

[supradad]

I wrote this up a couple of years ago:

http://www.supramania.com/forums/showthread.php?t=276

And here is a link to calculate your compression ratio before you purchase a head gasket: http://www.csgnetwork.com/compcalc.html

Very nice writeup. The calculations may be a bit out of my league. I also am limited on machine shop and speed shops here in the Portland, Maine area. Talked to a few already.

 

[p5150]

When it comes time to calc your compression ratio you can start a new thread and we will walk you through it. It really does make a big difference in overall compression ratio with little specifics like differences in head gasket bore diameter.

If you just want a 57 trim ct upgrade you might want to even consider raising the compression ratio a bit from stock to something like 9:1. This will make it a blast to drive on the street. If you ever plan on strapping on a big turbo then I would stick to 8.5:1 or so.

 

[Facime]

ohh yeah that keyway looks far worse than I first thought. but sounds like you made the call already.

As far as the forged pistons go, those Probes arent far off from stock price and seem like a good cheap way to go forged. I know nothing about em at all so thats not an endorsement. However Aaron at Driftmotion is a trustworthy guy and I would have no problem buying from him.

 

[supradad]

When it comes time to calc your compression ratio you can start a new thread and we will walk you through it. It really does make a big difference in overall compression ratio with little specifics like differences in head gasket bore diameter.

If you just want a 57 trim ct upgrade you might want to even consider raising the compression ratio a bit from stock to something like 9:1. This will make it a blast to drive on the street. If you ever plan on strapping on a big turbo then I would stick to 8.5:1 or so.

From what I've been reading, 57 is all I'll probably go. I'm looking for a fun relaible car, not a drag racer. I'll keep thking about the pistons and rod options.

I'll probably take your advice and start a thread about the compression ratio. It will be a few days before I do that though. I'll post a comment here when I do.

The big thing I think I need to concentrate on now is pulling the rest of the pistons and document what the remaining cylinder walls look like. Sound good? Then we can further the discussion on the boring. Also with p5150's post, I should probably remove the oil squirters for the piston bottoms and check them out. Can the check valve on the oil filter you referred to in your link be removed priot to magnaluxing?

Do I need to take measurements for the compression calclation prior to pulling the pistons? I also imaging it's time to invest in a good 4 inch micrometer and internal guage to start making these measurements, along with the head thickness.

 

[supradad]

ohh yeah that keyway looks far worse than I first thought. but sounds like you made the call already.

As far as the forged pistons go, those Probes arent far off from stock price and seem like a good cheap way to go forged. I know nothing about em at all so thats not an endorsement. However Aaron at Driftmotion is a trustworthy guy and I would have no problem buying from him.

I figured I'd try and get a better picture to make my case. Thanks.

 

[p5150]

I got my micrometers from harbor freight and they are just as accurate as all of the micrometers ive compared them to at my machinist. You could get a set of ID and OD measurement tools for under 50 bucks pretty easy.

When you take the block to the machinist be sure to tell them what you want for clearances. A lot of machine shops will set your oil clearances on the rods/main bearings at .003 or so when the TSRM calls for closer to .0012.

Looking at the scuff on #1 im not sure how much they will have to bore out to clean it up. You will need to know that before you order pistons.

The other check valve I was talking about is in the oil filter housing on the exterior of the block so yes, it will come off. A lot of people remove it alltogether and put a thermostat based oil cooler in its place. Since it is pressure-based it doesnt always work like some would prefer.

Also, I have a 2jz in my car, and it has been awhile since I built a 7m. The basics are the same, but there are some specifics that I may not be clear on so I may need to have some others chime in.

We will worry about ordering the appropriate head gasket for your ride once the head and the block are done. There are a lot of different options for head gaskets and you want to make sure you get the right one.

Are you consideriing doing some minor port work on the head too? Its really not that complicated if you keep it simple and just clean up the casting flash. http://www.supramania.com/forums/showthread.php?t=34310

 

[p5150]

Oh - one other thing. Were you able to tell if second gear was difficult to shift to? The synchros tend to wear out in the trans but I dont know if yours has the same problem. While you have the trans out may be a good time to replace the synchro for 2nd gear. It shouldnt cost too much.

 

[supradad]

I haven't made it to second gear yet, so I'm not sure if it's any good. Is there much involved with replacing the synchro? Is this something that should be left to a shop?

I'll look into the mic's and guages over the next few days. I was thinking of getting the block to a shop soon, but it sounds like I have more homework to do first. For me the next 3 weeks will be busy, so I won't have much downtime. I'll probably order some mic's and finish pulling the pistons and crank out of the block. When I do, I'll send more pictures.

You make the head porting seem so easy. Did you do your own head assembley as well? Thanks again!

 

[starscream5000]

What is involved with hardness testing, and what are the specs?

The test is basically used to see if the aluminum head has gone soft (usually on the exhaust side, rear ports) due to an overheat, if it has, start sourcing another head.

This is the very first thing you should have your machinist do is test for this, if it's soft, it's junk. Don't spend a penny in that head until you know for sure that it hasn't annealed.

 

[Facime]

Ive done head porting before and unless you are looking to change the shape of the chambers or do some radical race port its not a big deal.

in a nutshell you need a die grinder and some carbide bits/grinding stones/sanding wheels. Start by taking a fresh gasket and placing it squarely on the head where it would go. Then take a sharp scribe and trace around the inside of the openings. This is your match to line, you are going to remove material out to that point. while you are at it you are going to be removing any sandcast and smoothing all the surfaces inside the passages. Do the same thing on the manifold side ( a tad bit harder one the exhaust manifold because you are working in steel or cast iron. It takes time and patience but isnt rocket science. In the end you have a "match ported" head and manifolds.

For specifics on radical porting you would have to ask someone else, Ive never done it or had access to a flow bench, but I think a good match port is what you want.

 

[supradad]

The test is basically used to see if the aluminum head has gone soft (usually on the exhaust side, rear ports) due to an overheat, if it has, start sourcing another head.

This is the very first thing you should have your machinist do is test for this, if it's soft, it's junk. Don't spend a penny in that head until you know for sure that it hasn't annealed.

Can most shops do a hardness test? I guess what I mean is, is it a common test? Is it a go no-go test, or is their actually a spec for this? I did not see a spec in my service manual.

 

[HommerSimpson]

Can most shops do a hardness test? I guess what I mean is, is it a common test? Is it a go no-go test, or is their actually a spec for this? I did not see a spec in my service manual.

yes if your machine shop cant do a hardness test ... very first thing you do is look for another one.. then 2nd get head checked :}

 

[p5150]

I haven't made it to second gear yet, so I'm not sure if it's any good. Is there much involved with replacing the synchro? Is this something that should be left to a shop?

I'll look into the mic's and guages over the next few days. I was thinking of getting the block to a shop soon, but it sounds like I have more homework to do first. For me the next 3 weeks will be busy, so I won't have much downtime. I'll probably order some mic's and finish pulling the pistons and crank out of the block. When I do, I'll send more pictures.

You make the head porting seem so easy. Did you do your own head assembley as well? Thanks again!

Usually, addressing the second gear grinding problem can be put off by filling your trans with a good synthetic fluid like Redline MTL. It will make the synchros work better. You may be able to tackle this one yourself as long as you stay clean and organized. There should be a guide for it at www.cygnusx1.net - you have gone there and checked out everything right?

Head porting is easy unless you make it hard. Its kind of like washing a car - you wash it where its dirty and dont buff through the paint. You "port and polish" where it looks like it needs it. Just keep it simple and dont go overboard and you will have good results.

Yeah - I did do my own head assembly. It is a bit time consuming but it was worth it. I used a big c-clamp that I got for $1 at HF and wrapped a towel around the end with tape that braces against the combustion chamber. The top of the c-clamp presses on my custom adapter. I made an adapter from a wooden lawn/construction/garden stake that measured about 1.5x0.75 inches. I basically cut it so that it could be pressed down on the retainer by the c-clamp and allow access to the keepers. It looked kind of like a U when it was all done. Hope that makes sense. It sounds ghetto but it works and I have assembled 5 heads with these tools. 5x24 is 120 times that this has worked........

Disassembly is easy - just lay the head out with a towel under it and deck down. Put a magnet on the side of a 9/16 or so deepwell socket. I prefer 1/2 drive. Put an extension on the end of the socket to give yourself a handle. Place the socket firmly on the retainer and tap the back of the extension rather firmly with a hammer. The retainer will be pushed down and the keepers will fly out and stick in the socket. You can disassemble an entire head in minutes. :icon_bigg Dont worry about breaking a keeper. I have only ever broken one, and they are cheap.