Class 6 AMC Pacer.

"The Crazy Kanuck; RIP Oppositelock" (jukesjukesjukes)
11/04/2016 at 01:33 • Filed to: None

Gordon Olsen & Bob Stone entered in the Baja 1000 in 1979 with a 1976 AMC Pacer in Class 6 (production cars). The 4.2L in-line 6 was tuned to 200hp. It finished 2nd behind a V8 Ford Ranchero, only 2nd because it an impact punctured the radiator.

https://en.wikipedia.org/wiki/AMC_Pacer#Motorsports

DISCUSSION (11)

sn4cktimes > The Crazy Kanuck; RIP Oppositelock
11/04/2016 at 01:44

I have a 4.2L 258 I’m looking at having rebuilt. Wonder what they did to punch it up to 200hp... I’m looking at installing a new manifold injector kit with that rebuild which should bump “The Horses” by about 40-50. But that’s still far from 200. Wonder if they stroked or bored it out significantly?

shop-teacher > The Crazy Kanuck; RIP Oppositelock
11/04/2016 at 07:17

That is all kinds of awesome!

Invinciblejets > The Crazy Kanuck; RIP Oppositelock
11/04/2016 at 09:20

4.2 liters...6 cylinders..200hp. How is that even possible.

gogmorgo - rowing gears in a Grand Cherokee > sn4cktimes
11/04/2016 at 11:05

Just improving air flow could have gained a lot, plus a less “safe” tune. The 4.0 made a ton more power not too much later, with a shorter stroke, with the biggest difference being FI vs carb. You can tune a carb to be nearly as good as FI as well.

sn4cktimes > gogmorgo - rowing gears in a Grand Cherokee
11/04/2016 at 15:26

I just rebuilt and re-spec’d my carter and there was no change all. I think going FI and changing valves and the cam should give it some oomph. But still doubt I’ll get 200+. But I suppose I also want my block to live longer than 10k miles too...

gogmorgo - rowing gears in a Grand Cherokee > sn4cktimes
11/04/2016 at 16:42

The factory intake is pretty restrictive. We’re definitely talking more than just small modifications for sure, maybe porting the head an larger valves, and they probably would have put in a camshaft, but given the numbers people are getting by putting a stroker kit into a 4.0, I see very little reason you couldn’t get 200 out of a 258 without touching the block or internals at all. That extra 300cc isn’t that massive of an advantage.

sn4cktimes > gogmorgo - rowing gears in a Grand Cherokee
11/04/2016 at 21:37

The rebuild itself is primarily to address the 198,000km on the never rebuilt engine... not so much performance gains. But I figure it’s cracked open and all its bits are exposed why not do a “little tweaking” here and there. The FI kit should not only remove the ridiculous carter carb (remanufactured at least once, and then rebuilt by me), but it’s 700 miles of vacuum lines too. Plus give a nice steady power bump, and increase throttle response a LOT. That’s the goal anyway. I’m trying to get this Eagle not to mint original status, but quite nice and reliable and fun status, then I’ll sell off the Veloster Turbo. I figure the sale of that car should pay for a good chunk of the repair/resto of the Eagle. At that point I’ll start redoing interior, and getting a little experimental will things like coil-overs vs leafs in the back, converting drum brakes to rotors, redoing the audio etc etc.

gogmorgo - rowing gears in a Grand Cherokee > sn4cktimes
11/04/2016 at 22:23

Heh. 198,000 is cute. The 4.0 in my MJ had 240,000km on it when I pulled it out of a plow truck XJ and did nothing to it. The engine it replaced had 498,000. You don’t give AMC enough credit.

sn4cktimes > gogmorgo - rowing gears in a Grand Cherokee
11/04/2016 at 23:11

It’s been said, well written, that the MPFI kit isn’t to kindly to a “tired” engine. And given the state the carb was in when I got the car and it’s only semi-running condition I suspect that things are pretty gummy up in there. I think left to it’s own devices the car will drive until the wheels fall off. Which is fine, but it drives slow. It’s got torque coming out of every pore, but it takes a LONG time to get that hp working for it. I think I could slap the FI kit on there as is, I’m just not sure I should and expect it to not go badly .

I’d like to get the car moving a little quicker when I mash the pedal while feeling like it’ll start every time. I’d like to use it to get to the ski hill AND back...

The car itself is in pretty great shape. There was an allure to this beast even over some Volvos I looked into. And 2 of those were already turbo’d up to tire eating levels. I think a FI, re-tuned and re-built engine will make it a little sportier 4WD beast without removing the heart of the car. My Veloster isn’t comparable to a FiST or anything, but it’s got a decent amount of go once the turbo kicks in. I’d like something fun-isa still.

gogmorgo - rowing gears in a Grand Cherokee > sn4cktimes
11/04/2016 at 23:24

If you haven’t reconditioned the head yet, you can always grab one off a 4.o XJ at a wrecking yard, get the intake and MPFI bits as well. I’d say a full 4.0 swap but if you’ve already rebuilt the engine, there’s just cause to reuse it.

I kinda want an Eagle. But I have too many vehicles, all of them effectively projects, and don’t want to get rid of them just yet.

facw > Invinciblejets
12/01/2016 at 05:18

I’m late to this, but much worse has been done. AMC had a 125HP 5L V8. Chevy did even worse, meeting California’s tough emissions requirements by selling a version of the Monza that made 125HP out of a 5.7L V8. Indeed sub-150HP V8s were pretty common in the malaise era.