3.2 engine swap, second drive

dmcummins · 02-09-2009, 07:09 AM

Well in my previous post i stated that i wasn't impressed with the swap into my 73. My Boxster S was faster. WELL NOT ANYMORE!!!

I replaced the injectors and there is no comparison. Now its running lean, but HOLY CRAP, it will leave the Boxster in the dust. Now I understand the tire questions.

The AFM has been tinkered with in the past to lean it out and now I'm going to have to get it a bit richer. Its running around 15 to 16 and with the 02 sensor plugged in the idle is hunting. But I took it for a quick spin and I'm just amazed at the difference.

The injectors were the Buick/BMW or whatever bosch 0280 150 364.

I have to go now but the guys I have to meet are going to wonder about the big grin on my face.

Thanks to everyone who helped my through this and bear with me on my continual tuning. But I don't know how it could be much better.

Rot 911 · 02-09-2009, 07:11 AM

Great news!

jorian · 02-09-2009, 07:21 AM

Nice work. I wondered how that turned out.

SoCal70RSR · 02-09-2009, 07:32 AM

The same thing happened to me when I transplanted a 3.2 on a '70. I sent the original injectors to get cleaned but didn't install them right away (not sure if that made a difference) because the engine was at the machine shop. The first time I took the car out, I wasn't terribly impressed... I took the car to a local shop and they recommended I change all the injectors, at about $75 a piece - yikes! It was like night and day with new injectors. The car pulled very strong. I was pleased to have found the power it was lacking.

stlrj · 08:30 AM

Quote:

Originally Posted by dmcummins

I replaced the injectors and there is no comparison. Now its running lean, but HOLY CRAP, it will leave the Boxster in the dust. Now I understand the tire questions.

The AFM has been tinkered with in the past to lean it out and now I'm going to have to get it a bit richer. Its running around 15 to 16 and with the 02 sensor plugged in the idle is hunting. But I took it for a quick spin and I'm just amazed at the difference.

I would leave well enough alone.

A little lean at idle doesn't hurt a thing and is actually a where you want to keep it for the best low end and all around performance. Soon as you get off idle, the DME gets things plenty rich in a hurry.

As for the AFM, go ahead and enrich the mixture and watch how you quickly kill performance, but before you do, make sure you index everything so you can set it back to where it was.

The idle hunt is most likely your base idle set too high, so you might turn the idle bypass screw in a turn.

Cheers,

Joe
74 w/ 86 3.2 conversion

KeoRS · KeoRS's Garage

Thats awesome dmcummins;

What are evident signs that injectors might need changing on a 3.2?

p930man · p930man's Garage

Very interesting. I have just ordered a rebuilt set of injectors for my 3.2 transplant. I'm also
using the Buick injectors. I know I have two dead cylinders, the plugs are fouling out with fuel and the exhaust is very black. ie to rich. She runs like a two legged dog. The compression is
good on all cylinders. I hope to have the same success as you.

Best Regards p930man

dmcummins · 02-09-2009, 01:46 PM

I was pretty sure I was having a injector problem when I was able to unplug all 3 injectors on the drivers side at the same time and the idle didn't change. I had 4 injectors unpluged before it changed the idle. 5 unpluged and it finally died. The motor had set for years and I guess the injectors were varnished up, stuck part open. It really is a significant difference. Its night and day. I still need to fine tune it alittle as the idle is off and it hunts and stalled a couple of times.

dmcummins · 02-09-2009, 01:50 PM

Quote:

Originally Posted by stlrj

I would leave well enough alone.

A little lean at idle doesn't hurt a thing and is actually a where you want to keep it for the best low end and all around performance. Soon as you get off idle, the DME gets things plenty rich in a hurry.

As for the AFM, go ahead and enrich the mixture and watch how you quickly kill performance, but before you do, make sure you index everything so you can set it back to where it was.

The idle hunt is most likely your base idle set too high, so you might turn the idle bypass screw in a turn.

Cheers,

Joe
74 w/ 86 3.2 conversion

I'm definatly going to index where I am. But everything has been moved before I started. I took it for a drive and it didn't get richer off idle. Its staying around 15 to 16. Its was hard to follow as its so much faster and I forgot to hit record on my LM-2.

stlrj · 02-10-2009, 04:04 AM

Quote:

Originally Posted by dmcummins

I took it for a drive and it didn't get richer off idle. Its staying around 15 to 16. Its was hard to follow as its so much faster and I forgot to hit record on my LM-2.

I would not assume your numbers are that accurate because if they were, you would not be getting any performance at all off idle or anywhere else for that matter.

dmcummins · 02-10-2009, 07:16 AM

Quote:

Originally Posted by stlrj

I would not assume your numbers are that accurate because if they were, you would not be getting any performance at all off idle or anywhere else for that matter.

Your correct. I ran it again this morning and recorded it on the LM-2.

Cruising at 3000rpm I average around 14.

At WOT I average around 13.8 till it hits 4000rpm, then it drops like a rock to 11.5 at 5000. Then it climes back to around 12.7 at 6000. This was in second gear, but it looks the same in 3rd.

Im still having a problem getting it to idle. It will idle ok with the plug jumpered, but with the wire removed it hunts and stall's. When driving it has stalled or the idle will run high, 2000rpm's. I removed the ICV and cleaned it and before I cleaned it I could hear the ball moving.

stlrj · 02-10-2009, 07:53 AM

Quote:

Originally Posted by dmcummins

Im still having a problem getting it to idle. It will idle ok with the plug jumpered, but with the wire removed it hunts and stall's. When driving it has stalled or the idle will run high, 2000rpm's. I removed the ICV and cleaned it and before I cleaned it I could hear the ball moving.

Sounds like you need to get your base idle adjusted which should take care of the hunt and stall.

Meanwhile, I would leave the AFM alone, your mixture seems to be on the money.

Nine9six · Nine9six's Garage

While this is prolly not your issue, I rectified my hunting idle with a new O2 sensor. I had similar cause and effect with the plug jumpered on my 3.2

sharpshooter677 · 02-10-2009, 11:53 AM

wow...can the bosch 364s make that much of a difference? good investment then right? ha

DW SD · 02-10-2009, 01:51 PM

Quote:

Originally Posted by sharpshooter677

wow...can the bosch 364s make that much of a difference? good investment then right? ha

I think they make a HUGE difference if the old ones are stuck closed.

Glad to see this project coming together!!

If you have an old fuel tank with a lot of sediment, make sure you change the filter, too. EFI is sensitive to debris and fuel pressures.

Congrats!

Doug

dmcummins · 02-10-2009, 04:47 PM

The 02 sensor is new so I hope its not a problem. I also have a new fuel filter.

It did idle alot better with the stuck fuel injectors. Dont know why it hunts and stalls now. If I understand how to set it up, first I disconnect the 02 sensor to set the base idle air/fuel ratio with the 3mm screw on the AFM. I believe I had it at around 15-16, the idle is bouncing and so is the reading. Then I hook the 02 sensor back up and jumper the plug and turn the idle screw to adjust idle. It bounces around some but it was averaging around 800-820.

Then I turn off the car and pull the wire out of the plug and start the car. Then it starts to hunt and stalls. I drove the car and the idle seems to stick around 2000rpm a few times and then will drop and start to hunt till it die's.

Any idea's?

stlrj · 02-10-2009, 05:51 PM

The base idle speed is not the same as the idle mixture. Try setting the base idle speed. That should take care of the hunting and stall.

dmcummins · 02-10-2009, 06:03 PM

I guess I'm missing something. How do I set the base idle speed.

POORSH · 02-10-2009, 09:34 PM

That is great to hear as I was getting nervous from your other post. I am still waiting to get my '72 3.2 swap back from Jimmy Deering. Getting back to the tire question. How wide can you go with an early narrow body?

dmcummins · 02-11-2009, 03:18 AM

Quote:

Originally Posted by POORSH

That is great to hear as I was getting nervous from your other post. I am still waiting to get my '72 3.2 swap back from Jimmy Deering. Getting back to the tire question. How wide can you go with an early narrow body?

I have 205/60X15 Kumo's. I don't think I could go any bigger. These are on 15x6 Fuchs.