Post by: TopNotch on September 15, 2011, 09:03:45 pm
You may recall from this thread (http://gafieroclub.org/bbs/index.php?topic=782.msg6231#msg6231) that I had acquired a later model cylinder head that I was going to use on my duke rebuild. As it says in that thread, my research showed that the head was a 91-93 VIN A head, and I thought it would fit on my 88 duke block. Well, as it turned out, two of the bolt holes didn't match up. So in true "make it work" fashion, I modified the head as shown in these pictures:
I filled in the old hole with a mild steel rod, and drilled a new hole. The rod is held in with JB Weld. With nearly 1000 miles on the engine since getting it back together, and no problems, I think it worked. Here's the other hole I fixed:
I wanted to use Big Block Chevy roller rockers on the head, so I had to drill and tap the rocker stud holes as shown in these pictures. (The head in the pictures is my old one, which had a crack, but it was good practice.)
Actually, drilling and tapping for the bigger studs was easy. But enlarging the holes in the guide plates was hard -- they are made of extremely hard steel.
The roller rockers I used were some stainless steel ones I found on Ebay. Below is what they look like on the engine. BTW, the pushrods I used for this combination are Melling MPR-389. They are for a late 60's - early 70's Ford V8.
The head was not the only mod I did to the engine. I put in an Accelerated Motion camshaft with a little more lift and duration than stock, and an all metal timing gear set:
I also put on a later model starter to save weight. This picture compares it to the original.
BTW, the new starter works just fine.
Below is the engine back on the cradle, with re-assembly almost finished.
Before I put it in the car, I put in oil, put in the pressure sender, and cranked it over with a battery. A meter on the sender showed I had oil pressure.
Back in the car...
The finished product...
So, you may be asking, "How does it run?" Well, it runs fine, but I'm not sure how much better. Before the rebuild, it would start to run out of "oomph" at 4500 RPM. Now it feels like it has more to go, but I'm afraid to run it up higher. Maybe after I have a few thousand miles on it.
Post by: Roger on September 16, 2011, 07:42:26 am
Very nice indeed!
I'd call it a 'FrankenPat' engine.
What did you do with the bore and stroke (if anything)?
Did you use the stock type oil pump?
Any ignition mods?
Inquiring minds want to know.
Post by: TopNotch on September 16, 2011, 09:22:36 am
And BTW, if anyone is curious about the valve cover, see this thread (http://gafieroclub.org/bbs/index.php?topic=329.msg3138#msg3138).
Post by: TopNotch on September 28, 2011, 03:31:31 pm
Post by: oldone on September 28, 2011, 04:22:26 pm
Post by: TopNotch on September 28, 2011, 04:27:17 pm
Edit: I rebuilt the engine before the heart attack. I just wrote about it afterwards. But driving it is good therapy.
Post by: oldone on September 28, 2011, 04:42:10 pm
Post by: TopNotch on September 28, 2011, 05:04:47 pm
Post by: aerodonamic on October 10, 2011, 05:54:38 pm
Post by: TopNotch on October 10, 2011, 06:18:37 pm
It is the starter for a 1998 through 2000 Pontiac Grand Am, among several other GM cars.
I had to shim it quite a bit to make it mesh properly on my car. It needed shimming in, so only at the outer bolt. I used washers instead of standard shim pieces.
Post by: GTRS Fiero on January 26, 2017, 01:44:21 pm
Post by: TopNotch on January 26, 2017, 03:26:23 pm
Is this essentially a streetable version of the SD4?
Not even close. A stock 88 duke is rated at 98 HP, and I get maybe 120 out of this thing. But a SD4 can easily put out 300 HP.
But in any case, I call this a XD4 (extra duty 4). And it now has over 38,000 miles since the rebuild, so at least I didn't break it.
Post by: GTRS Fiero on January 26, 2017, 03:29:10 pm
My understanding is that the SD4s were not streetable, for both emissions/certification and reliability issues.
Post by: Raydar on January 26, 2017, 07:35:38 pm
...
My understanding is that the SD4s were not streetable, for both emissions/certification and reliability issues.
I had a (fairly mild) SD4 for a while. It was loud and it was thirsty, but I think if I had ever gotten it tuned correctly, before I sold it, it would have been quite streetable.
It was the rest of the car that made it not practical. Had a leaky Automoda convertible top, and really crappy brakes.
Post by: Raydar on August 23, 2017, 09:47:56 pm
Pat, did they send you the specs for your cam?
I have run across an engine (a Duke) that's been rebuilt and ported, and had a reground cam installed, and I'm trying to decide if its worth my trouble or not.
Did you rebuild your force balancer? Or did you just buy one of Rodney's units?
Post by: TopNotch on August 24, 2017, 07:55:14 am
I took my balancer apart, saw that it looked fine, and just cleaned it and put it back together, and back in the engine. As you know, it's also the oil pump, and my oil pressure is very good.
BTW, you're supposed to fill the oil pump cavities with Vaseline on one of these when you install it, if it's dry (new or re-assembled).
Post by: Raydar on August 24, 2017, 11:02:24 am
Can you share your specs?
(This engine is on Pennocks. I don't know anything more about than what is in the ad.)
Edit - here's the cam specs...
https://www.flickr.com/photos/30128663@N06/35277270573/
Post by: TopNotch on August 24, 2017, 01:54:53 pm
Post by: Raydar on August 24, 2017, 02:05:06 pm
Click here (http://gafiero.org/docs/CamSpecs.pdf) to see my cam specs.
Thank you very much!
Did you retain the roller lifters? Or did you have to go with flat hydraulics?
Post by: TopNotch on August 24, 2017, 02:11:23 pm
Post by: TopNotch on August 24, 2017, 02:22:06 pm
Post by: Raydar on August 24, 2017, 02:55:32 pm
Post by: GTRS Fiero on October 08, 2017, 09:39:36 am
I'm glad we don't archive threads on GFC.
Does the EGR being under the air filter put a lot of heat there? I don't see an EGR tube.
Post by: Raydar on October 08, 2017, 10:56:57 am
I'm sure the heat introduced into the air filter housing is inconsequential, compared to the heat (exhaust) piped directly into the manifold.
Post by: GTRS Fiero on October 08, 2017, 12:22:11 pm
Post by: TopNotch on October 08, 2017, 12:44:35 pm
Post by: GTRS Fiero on August 18, 2018, 10:04:05 am
Post by: TopNotch on August 18, 2018, 03:44:20 pm
All fixed now, and the car actually feels like it has a tad more power.
Post by: GTRS Fiero on August 18, 2018, 03:47:43 pm
Post by: TopNotch on August 18, 2018, 03:55:57 pm
Post by: GTRS Fiero on August 18, 2018, 08:30:49 pm
It was actually suffering a little bit at the 35th. Turns out I had stuck sliders on one rear caliper. (I wondered why there was so much break dust on that wheel when I cleaned for the car show.) When I pressed the brake, the caliper would slide enough to pull the outer pad to the rotor, but when I released the brake, the pad would stay snug against the rotor.
All fixed now, and the car actually feels like it has a tad more power.
Better at the 35th than RFTH. That trip netted a bit over 830 miles on my Fiero. How many did you put on yours? About 2,,000?
Post by: TopNotch on August 18, 2018, 08:59:33 pm
Better at the 35th than RFTH. That trip netted a bit over 830 miles on my Fiero. How many did you put on yours? About 2,,000?About 700 each way. And I did the 2nd 700 all in one day.
Post by: GTRS Fiero on August 18, 2018, 09:05:46 pm
I think you started home before 8am, so it shouldn't have been a bad drive. Probably very scenic.
Post by: TopNotch on August 18, 2018, 09:33:39 pm
Post by: GTRS Fiero on August 19, 2018, 07:54:23 am
So, 1,400 miles, plus the cruises. My best was 1,100 miles in 11 hours, but I started at 7pm, after a day of hiking, then drove through a snowstorm in the mountains.
Actually, that's not true. I headed West, and crossed a time zone, so more like 12 hours.