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98cobra+75280z

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Im seeking advise on what my options are regarding my car. So I have a '77 280 that I initially swapped a '82 l28et and MSnS into it but I blew a head gasket and when I tried to get the motor apart all the bolts on the front cover and oil pump broke and were seized, so there was not any easy way for me to take the motor apart and fix it. I found a '83 l28et for sale on here from username "monster reem" and we agreed on a price of $650 for just the motor. It was advertised as a perfect working condition motor pulled from a running car. This being the main reason I purchased it since I hadnt the time to rebuild mine. Over the summer I worked as an intern at Ford Motor Company which made it impossible to work on my car. So I bought the motor and took it home then headed back to Michigan. At the conclusion of my internship I was able to pull my motor and drop in the new one in one day but upon starting the engine it had a severe knock. I emailed "monster reem" and told him about it the fact that this motor had to be hurt before I purchased it. I asked him if it was possible to get my money back but he refused claiming it was sold as is and I must have hurt the motor and am just trying to get my money back. Here are some pictures of the motor after I took it back out and took it apart to try and see how bad the damage is.

 

post-5822-083645900 1345676686_thumb.jpg

post-5822-009095800 1345676695_thumb.jpg

 

So i guess my main question now is where (if anywhere) can I go from here. I'm finishing up school and getting my degree in mechanical engineering this December and also getting married in April so money is extremely tight. The head is destroyed I'm assuming and I know piston 3 is done as well. I'm hoping there will be a decent way to get some of my money back so I don't have to part out my car to get money until i graduate and get a job.

 

Thanks guys.

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My eye is untrained, but that looks like other detonation photos posted on here. How long did it run before noticing the "knock"?

 

To save money use the head and pistons from the old motor. You didn't say but I assume they are still good.

 

Other cheap options are a p79 head, cheaper than a p90, and used pistons. Post a sob story in the wanted section and I'm sure someone will help you out.

Edited by ctc
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it had the knock on initial start up. I have no clue when the damage occured as I am pretty sure it was damaged when it was sold to me. And this isnt intended as a sob story just wanted to know what people do on here and if any of this stuff would be salvageable. Also to watch out when buying because I am sure I'm not the first guy to buy something and have this happen. As for the P79 head does it perform very well as compared to the P90 and is it a direct swap that will still retain the turbo exhaust since I believe the P79 has circular ports and not square?

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it had the knock on initial start up. I have no clue when the damage occurred as I am pretty sure it was damaged when it was sold to me. And this isnt intended as a sob story just wanted to know what people do on here and if any of this stuff would be salvageable. Also to watch out when buying because I am sure I'm not the first guy to buy something and have this happen. As for the P79 head does it perform very well as compared to the P90 and is it a direct swap that will still retain the turbo exhaust since I believe the P79 has circular ports and not square?

 

Sorry, didn't mean to offend with the sob story comment. What I meant was that if you post that you are a college student looking for parts to get your car going again, people may be more inclined to give you a break on pricing. They might even send you what you need for the cost of shipping. I know that has happened on other forums as well as this one.

 

I personally have not run the P79, but my understanding is that it is identical in performance to the P90. The P79 has liners (round ports) that some say wear prematurely in a turbo application and might break off and damage the turbo, but that seems to be internet lore more than fact. If you search here there are some people that have used the P79 in a turbo build, I suggest you look through those threads.

 

Is the head from the old motor bad/warped? Why not just use it. If the problem with the old motor is the bolts into the block. All the other parts should still be ok to use. Take two bad motors and make one good one. Should be up and running for the price of a head gasket and seal kit.

 

My 2 cents...

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No offense taken, I was just looking for some advise about the motor not really the events leading up to me having two broken ones haha. Is there a good engine rebuild book somewhere that will help me out since I have never rebuilt a motor before.

 

Thanks again for your replys

 

 

 

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Maybe you just paid $650 for a front cover. They should swap. If the only thing wrong with the 82 engine is a head gasket, then it's labor and gaskets to get back on the road.

 

There's always small claims court, as far as trying to get some money back. Might be worthwhile, if you think you can build a case.

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I suppose that I now have the most expensive front cover you can get in stock form lol. Thanks for the book tips, I'll have to grab one. As for the parts that are actually ok they will be in the sale section if people are looking for turbo parts (minus the block and head of course).

 

As always thanks for your guys help

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Yea I'd just do what I could to get the front cover bits swapped over and get the old motor functional again.

 

That said, I wouldn't call this a total loss. You now have a spare P90 and block to build, if you so desire. That P90 is far from ruined. In fact, I'd say it just makes a perfect candidate for chamber reshaping as long as the deck surface is indeed flat. Since you're going into mechanical engineering, I'd suggest waiting to see what kind of equipment your school will let you have access to. I know the local UC here has an extremely intense machine shop and student projects that are completely unrelated to any class project are everywhere. They'd usually rather you USE what they have, even if for personal use, since most students are too busy with their noses in books to care about APPLICATION.... :-)

 

So read up on chamber welding. It's not as mystical as some make it seem. It's the reshaping that's a very complicated bit, but doing basic improvements should be pretty obvious to anyone going that far. I'm sure you could easily model some basic chamber shapes off of MONZTER's head and be a better off than a stock P90. Spark plug relocation done right can pay huge dividends. The P90's deeper chamber (shorter valve) can also have the benefit of making it easier to unshroud the valve and welding the chamber will allow you to keep the CC's back down and compression up. If I were doing this (and obviously I'm not you, even though I DO have a spare P90 sitting behind me as I type), I'd be shooting for a compression of about 8.5:1 giving me flexibility to run sub 400hp on pump fuels, or much higher on meth/eth fuels. If I was going for meth/eth only I'd shoot for 9.5:1+ even as high as 10:1. If you know you're going to run pump gas 90% of the time and want to be able to run huge power keep the compression lower, in the lower 8's or high 7's.

 

If you're able to use your school's welding equipment and CNC stuff for next to nothing, then making a really bad arse head shouldn't cost you much at all. If you wanted to get fancy you're looking at spending money on valve seats, valves, springs, cam, stem seals, etc. And also, don't forget you can save your old valve seats from machine murder if you get some old used valves and grind them down a bit, then install them on the head to be CNC'ed. Now you have a valve in there you don't mind hurting and preventing a mistake from taking out all your hard work (especially useful for hand port jobs)

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I'm sure you can find a complete L28 block from a non-turbo 280zx (F54 with p79) and simply swap the turbo externals onto it.

 

They are pretty cheap and will live with 10psi or less for years if it is simply swapped for the L28et lump as long as your injectors and engine management are working properly.

 

I would recommend running it at the stock boost for a bit before moving toward more boost.

 

Also....you should use 93 octane with that setup to be safe and then experiment from there.

Edited by HowlerMonkey
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I hate to hear story's like this about being ripped off from someone on this forum, 650 isn't a bad price per say for a decent running motor but a popped one its pretty steep. The options with the regular L28 are there, they are plentiful and cheap, however i'm finding the turbo motors aren't all that expensive to source either just have to look daily like a religion every classified you can, online and on paper. Good luck. I'd find a decent L28 block if I were in your situation.

 

 

Detonation ate that motor, I can see if clear as day.

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