Sick 86 Shelby turbo

[Capt'n Dave]

I have a rather mind boggled situation,I blew the old turbo,with one of the turbo home boost ideals,my fault... replaced it with a rebuilt from majestic turbo,changed exhaust to 2.5" all the way to rear,new cat and all ,installed boost guage,now the car will make boost and spool up fine when cold,but after awhile,about the time it warms up,falls on face no boost,replaced the coolant sensor,the only codes are 12,33(non-a/c) 55,like most of you i brought this car from the dead,set for ten years,68K on it... I have come to like the way it handles,etc. put about 500 miles since running,need to finish out,so it can go to the track,any ideals as to what the problem is? replaced ecm and spark control also... seems to be a time related thing,once it falls on face,you can restart it,runs like nothing was wrong for the same time,maybe it is in the limp mode,not sure,HELP!!!!:banghead:

[tryingbe]

Have you check spark and cam timing?

[Capt'n Dave]

I also changed the heat range on my plugs from RN12yc to RN9yc per Dempsey's recipe,No i have not checked the Timming,When i got this car from Ebay,I was told it had a racing head on it,I will do an compression Ck and look at the timing,this is my first turbo car i ever owned,it is one of 386,Silver Blue stripping,cool looking car,just looks like a racer,Thanks for the info.

[WickedShelby88]

yeah sounds like when it goes into the closed loop on computer end the base timing might be way off or something else timing related. Either way after that happens the computer doesn't like it and it runs like a pig rich fuelie.

[Capt'n Dave]

I am getting ready to pull it in the shop and go over timing this morning and pick up a/f guage and install it to get a look at that end of it...also do a compression check,I will keep you posted.. Thanks

[Capt'n Dave]

That was a good call on the timing,cam timing is right on,spark was off a bit,reset and now it really screams when cold,i now think that my wastgate might be opening a little early when warm,will try to adjust travel on arm to see what that will do..

[Capt'n Dave]

yeah sounds like when it goes into the closed loop on computer end the base timing might be way off or something else timing related. Either way after that happens the computer doesn't like it and it runs like a pig rich fuelie.

you are so right on the timing,reset it ,runs great when cold,not as bad when warm,the plugs show that it was in fact running rich,now i think it might be a weak wastgate spring,will try to adjust it,let you know... Thanks!:thumb: