Rebuild options: advice needed

Hey All, I have been out of the game for more than 10 years, and I'm trying to get back into it. I have parts in bins I don't know what they are or how I came across them... Lol


Anyway, I recently developed some serious blowby on my 85 turbo. Has been upgraded to TII and 14 lbs boost. TII intake, exhaust, computer etc. All ran great for years. Stock lower end. It has the 287 head and the dish pistons. Compression was low in cylinder 1. Turns out the ring lands broke off. There is minimal scoring in the cylinder, can't feel it with finger nail so thinking a light hone will be plenty.

Here's the question, I found in my bins of parts that I have a couple sets of TII rods and pistons. I am currently unemployed due to coronavirus, and trying to do the best bang for my buck fix on this. Should I look to replace the broke piston with another 85? Is it better to swap in all the TII rods and pistons? Can I even do that with this crank and block? Are there any concerns?

Since I'm running a stage 2 glhs computer, is it made for tII pistons anyways? I've been okay for a long time, well up until now with my g head and 85 pistons. If you saw my other thread from a couple days ago, you know I have a 2.2 commonblock that I don't remember where I got it (lol) standing by, but I don't exactly have the cash to build that up at the moment.

Looking for advice please. Also, pics of carnage and the pistons and rods I found.

Thanks in advance.

-Andrew

http://imgur.com/a/DkFgtIZ

TII computer was made for 782 head, not G head.

Do you have a 782 head to use?

Quote:

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Originally Posted by tryingbe

TII computer was made for 782 head, not G head.

Do you have a 782 head to use?

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I do but it's of unknown condition. It is the one that's sitting on the aforementioned common block.

Welcome back,
Yes you know you have Turbo Mopar disease when you have no idea where and when you got some of the parts you uncover in storage. Many of us have been there!
As Harry was saying, the calibration your running was meant for a swirl head. You would be wise to run the swirl pistons with the swirl head (you can use the TII rods) they bolt in. You would also need to run a 86 distributor, but you probably already have that installed in your 85. The 85 distributor along with 86 electronics doesn't work well, so that was probably already changed out.
Might consider drilling a tapping out the headbolt holes in block for 11x1.5mm. This was a running change in late 85. Very few 85's have 11mm headbolts. The 85's use 10x1.5mm bolts. If you end up just replacing the one piston with another 85 piston, better check the injectors. IMO, #1 is odd one to break a ring land on. Usually it is #3 or 4 as they typically run hotter and leaner. If you go with 11mm headbolts and the 287 g-head, you will need to drill out the headbolt holes a bit. Easy to do this at home in your garage. If drilling and tapping block , just make darn sure they're dead straight and you using a nice sharp bottoming tap using plenty of cutting oil. I use my deck plate as a guide for drilling & tapping 85 blocks for 11mm bolts. Easy enough to make up a jig too.
Todd

Running the G head and swirl pistons is the right move.

Normally I always agree with Todd except on this issue.

All you're doing is making it less knock sensitive.

Cal is slightly different, not worse.

New combo is better.

Good luck!!

Thanks
Randy