I recently replaced my 2.8 with a junkyard Lumina APV van 3.1 V6. I used the FOCOA conversion kit which included a flywheel, timing chain/gear kit and an adjustable fuel pressure regulator. The engine is installed and running. The f.p. regulator is adjusted to 42 psi (indicated at full throttle). My problem is that the motor has excellent mid-range power but falls on its face after 4000 rpm. It will pull to redline but it seems like an eternity to get there. I've tried both the stock and FOCOA HP computer chip, no difference. The exhaust looks a little rich to me. I've removed the ceramic interior from the catalytic converter. The muffler is not blocked. I've inspected the entire air intake and filtration system, running the engine without the filter. No difference is evident. I'm concerned about the in-tank fuel pump. What's it gallons per minute spec? How can I determine if the injectors are clogged, blocked or are just not up to the job? Any other suggestions of things I can test or check, without just replacing stuff??? I'm getting desparate.

I thought the 2.8 distributor got wonky at high RPM. Is it the same distributor? THat may explain it.

Greg, yes it's the 2.8 distributor with 100,000 miles on it! I'm assuming that if the bearings are tight that it should be ok.

The stock 2.8 coil is weak after 4000 rpm. I don't believe there is a problem with the distributer. I'd go with an MSD coil.

I vote for weak spark too.

Also take into account that the Lumina van 3.1 was a low perfomance , low rev version that only made 120hp, which could expain it

You need more fuel pressure.
42 lbs is almost stock.
I have my 3.2 at 48 PSI at WOT.
It pulls untill it shifts
Dan-O

i would have to agree with what sid said and that the engien is not a high performance engine like the fiero engine. I don't think it has the same camshaft and because of this the redline in the 3.1 minivan engine is lower the the stock Fiero of 6k rpm. The lumina engine might have a redline of 5500 or so and when it starts getting up to 4000 or so it starts to get slow cause teh valvetrain was not designed to turn such high rpm.

however I do believe that the lumina engien came with more the 120 hp. If it only had 120 hp then that isn't much for a minivan designed to haul 6 people. I would say that engien is rated at 160 hp but the valvetrain isn't meant to turn high rpm and that is the cause of the dropoff in power not the ignition coil.

Also check the timing curv. chek the max deg. @4000 rpm maybe you are not getting enough advance

Is it the APV 3.1L TBI? Did you swap it into a V6 Fiero? If so, then the fuel pressure is too high. The V6 uses 45 PSI. The TBI engine uses 15 PSI.

The Dust Busters never had a MPFI 3.1L only the TBI. They switched to the 3.8L SFI as an option in 92.

So I would say the FP is too high. Now, if you started with an L4 Fiero, it should be ok.

Guys, thanks for all of your reply's. It gives me alot to think about. I think, this weekend, I'll crank up the fuel pressure to 48 psi and see what happens. Yes, I did install the MPFI from the 2.8 on to the 3.1. My 100,000 mile distributor just gave up the ghost (ignition module), so I put in a rebuilt NAPA one last nite. Now, all that I need to do is check the timing.

Is 38 degrees@4000 rpm, the max advance?

Make sure you used your 2.8 heads... But you main problem (other than crappy spark) would be that damned mini-van cam...