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I recently installed a 1986 turbo 2 engine (no intercooler) from a CSX into my 1985 Shelby Charger that had the original stock t1 engine.
I believe I have a detonation problem because I've got high crankcase pressure, exhaust is coming out of the dipstick.
What am i doing wrong? Is the 86 t2 engine compatible with the 1985 t1 logic and power module?
I'm using the original 1985 intake and injectors. Are there any incompatible parts? Help!:(
You really need an 86 L body LM. The timing is quite different between the two computers because the head changed. Although, if you have that much blow by it's probably time for a leak down test. How do you have the PCV set up?
the PCV is setup as stock. seems to be working fine.
should I change the PCV. someone said that a toyota Supra PCV works better. any thoughts?
Yes, i think you need to do a leakdown test. :)
But i will tell you this up front: Something is messed up in the bottom end. Worn rings, gouged cylinder wall, cracked ringlands, partially melted piston, who knows. A leakdown test will help you narrow it down between a problem in just one or two cylinders vs the engine just being uniformly crappy due to wear.
One way or another if you have bad blowby you will have to take the engine at least partially apart to fix it. The only relationship that detonation (which is an engine performance / drivability issue) has to blowby (which is a bottom end hard parts issue) is that detonation can lead to excessive blowby by damaging pistons. IF that's the case, the damage is already done and will have to be fixed. You wont be able to just swap some parts on the outside of the motor and make the blowby go away. :(
I will do leakdown test. I suspect cracked ringlands due to poor timing because i am using the 1985 logic module for this 1986 head.
85 and 86 heads are different. I think the 86 head is a swirl head.
I have 2 choices because I still have the original 1985 non-swirl head:
1. When I recondition the motor should I keep the 1985 electronics and put back the 1985 headhttp://www.turbo-mopar.com/forums/im...cons/icon5.png the 85 head was reconditioned about 10,000 miles ago.
or 2. when I recondition the motor should I buy a 1986 logic module for the 86 headhttp://www.turbo-mopar.com/forums/im...cons/icon5.png
what would you guys dohttp://www.turbo-mopar.com/forums/im...cons/icon5.png
Since you already have the 85 head and it was recently gone through i would just run that. Trying to decide between cylinder head designs really doesnt matter much until you are into the 15+ psi boost range and want to start talking about detonation-resistance of combustion spaces or which is easier to port. In the end there are fast cars running both heads so it is kind of a matter of preference. For now i would run the 85 head just to make your setup reliable for the least amount of money and worry about which head you want to run when you get to 'the next phase'.
Be aware that mixing and matching bootom ends and cylinder heads can lead you to troubles too. Higher or lower compression than normal. The pistons are different for g-head than for swirl. If you change to swirl head and swirl shortblock as Cordes stated you will not only need to change LM's but wiring as well. I think you should just run with 85 block and head too. The 85 motor is fine from a performance standpoint. If you decide that intercooling is in the future, I would consider having the blocks headbolts drilled and tapped for 11mm instead of the 10mm. Chrysler did this as a running chage in late 85 (86 model year). Have the machine shop do this, as they must be done straight and tapped correctly. If you do this you will need to run a slightly bigger drill bit through the 85 cylinder head to accommodate the 11mm headbolts. This can easily be done at home.
Good luck!
85 g-head(287) cal would have more timing than a 86 or above swirl head(782) cal.
Running 287 cal with 782 head would mean knock....
If the 86 engine isn't physically damaged, change the LM to a 86 TI and the distributor and hep sensor and you should be fine.
high crankcase pressure.. depending on leak down test results.. i'll bet you need to pull the pistons, hone and install re-ring to solve the issue
As I have recently discovered, how you have all of your vacuum lines connected to the solenoids can cause detonation. If you removed them during the engine change it is easy to swap them around incorrectly. I realize that you may have greater problems but making sure this part of the setup is correct eliminates one more possible area of problems.
Here's a good read on detonation and how exhaust gas gets into the crankcase - through the oil rings' drain back holes.
Rings and ring lands - bend or crack . . . .