irv

So my 1989 22r badly needed a new timing chain as it was the factory original and was very loose and had broken guides. I was also given a 268 camshaft for xmas from my brother. We decided to pull the whole engine and do a good desmog and take care of all this work.

My truck has had a Weber 32/36 prior to this work and still has it. 1 1/2 turns out on the mixture screw and set idle to 700 rpm.

I removed and block plated everything except for the egr crossover (egr valve is removed and blocked though), water block plates and the under intake block plate. Everything else is gone and I now have only 2 vacumn lines. One vacumn line from the carburetor to the distributor and one from the intake manifold to the distributor. I felt confident that everything was blocked and sealed well.

Timing chain and camshaft went in well aside from stripping out one head bolt. We successfully heli coiled the block in that spot, installed a new head gasket and torqued all head bolts down to spec. Valve clearance was set to what the new camshaft specified.

The motor was put back into the truck and everything was buttoned up thoroughly and we felt good about it. Truck seems to start up, run and idle great. The timing is set to the specifications written under my hood.

I got the truck out on the road and instantly knew it was more sluggish than before. I have to give it much more gas to maintain the same speeds and up hills it just feels under powered now. I would say that it is down 1/4 to 1/3 of it's previous power.

My truck is a 2wd, though it has extra leaf springs added and ball joint spacers, and has stock sized 195 75 r14 tires. I used to get between 28 and 33 mpg cruising at a mild 50mph over long distances. Bombing down the highway at 70 mph+ I would typically get 25mpg. I can't ever remember getting less than 25mpg.

On a mild 50 mph drive I just got 22.5mpg which is abysmal compared to 33mpg that I have gotten on several occasions on the exact same drive. 33 is rare though, about 30mpg is normal for me on such a drive.

I was concerned that my aged front brakes may be sticking because they did not spin nearly as freely as they should, so I installed brand new calipers and pads in the front. I also installed brand new front wheel bearings. My plugs were over 2 years old so I put in a full set of properly gapped plugs. Both of these things I think helped slightly but were not the root of my problem.

So, long story short, I replaced the timing chain, added a new cam and de smogged the truck and I am now at a large loss of power and mpg.

What might I have done wrong to cause these results? What might be a next step for me to take?