Quad 4/Hybrid Swap For Fun Commuter?

[Blue Shift]

The engine in my 86' 2M4 automatic car is getting old. And even if that wasn't so, I need a more inspiring engine for my daily commuter. I have a TGP engine in my garage, but at 15/23 MPG in original form, I'm thinking that's not the direction I want to go. Don't get me wrong - I hate all the greenie carbon footprint BS they brainwash us all with here in the PRK. To me, it's about money - how much of my first hour of work I end up working for free. I also have a 90' 2.5, with the D port exhaust ports, and better intake manifold rated at 110, but the mileage and the performance are unlikely to be much better than my current duke.

I was sort of amazed to find that the Quad 4 easily holds its own vs the duke in the mileage department in the same chassis as the 2.5, while delivering literally twice the power in HO form. WTF M8? I know, Ecotec, Ecotec, Ecotec, except that I can't afford the time and cash to do an OBD2 swap that passes the PRK BAR examination right now. I'd love more than anything to have a Turbo DI ecotec from the Cobalt, but yeah. That and I don't have to do anything to the Q4 to make 180 HP, where I'd either have to find the very latest NA Ecotec, or modify an earlier one to get the same level of power, and would then possibly fail the inspection.

I believe the head gasket issues have been resolved by the aftermarket, and there are long lived examples of Q4s. I would replace the gasket, and perhaps pick the 086 head and cams, and put them on the sturdier later 2.3 block, or maybe go with the 2.4 Twin Cam block which is even stronger. The issue with the hybrid appears to be that the combo with all stock parts makes ~11.4:1 compression... Which would be wicked if you can run premium on that, and not so wicked if not. Anybody have any familiarity with the hybrids? There used to be a killer article detailing all of the parts, with recommendations on what to pick and choose to build a strong Q4.

And going from auto to 5 speed should be a huge boost in freeway mileage anyways, so that's not out of the question. I just hope I can crawl along at 5 MPH in traffic. My DOHC car won't go below 7 or 8 which is a pita in heavy traffic.

Thoughts?

[Blue Shift]

http://www.hotrod.com/techarticles/olds ... index.html

Here we go. Article on mixing and matching the best parts.

[p8ntman442]

91-92 HO is the the best combo of parts. You dont need to use any 2.4 crap.

the best part is , no EGR, came stock with 5spd, the only emissions stuff you need is evap canister, oil air sperator,and 02 sensor.

Felpro headgaskets = no failure.
33mpg highway is not bad.

[The Dark Side of Will]

Building a hybrid is ALWAYS harder and more expensive than people make it out to be. Building a 2.5 Q4 stroker is one of those things.

Most 4 cylinders are economy engines made to run low octane gas for cheapskates. The iron Duck is in this class.

The Q4 is in a fairly small class of high performance naturally aspirated 4 cylinder engines. The high compression and free breathing REALLY help the highway mileage. The Iron Duck needs a 3.35 rear to hit mid 30's in gas mileage. The Q4 does it with 3.61 and maybe even 3.94.

[Blue Shift]

Yeah I dunno where I got the Quad bug from all of the sudden, but it just makes sense vs putting a later model duke in. If I have to change engines, I just have to make an improvement in the process. The only possible claim the duke would have is long term reliability, but probably not even that. I figure I better not fuck around with the 2.4 hybrid and just use a whole box stock HO Quad. The thing about absolutely minimal smog equipment kicks serious ass as well.

Hey p8ntman - did they strengthen the blocks in 91-92? My research isn't complete, but I read up about cracks in the earliest blocks, and the 88 heads having gnarly oversize exhaust ports that don't help either. Seems that the aftermarket gasket will solve the blown HG problems, and I take it I want the 086 head? I've read of head cracking issues, but it shouldn't be hard to find replacements.

[p8ntman442]

None of the blocks will fail except when you put a rod through them. Ask Bryson.

086 = best, but if your going to port a 456 will do just fine, just a little more port work to do. q4 heads crack, and to change them you have to do a complete gasket set. thats just the facts. I just picked up a 3k mile old rebuilt 086 on ebay for 150. for fiero owners the engine may be expensive, but its really a cheap motor to rebuild.

Get one out of a JY thats running, and do the swap. If it blows, rebuild it. If not youve saved $$$. The guy who won the most races in our class last year was Whoopin us with a $100 JY motor.

[The Dark Side of Will]

Yeah I dunno where I got the Quad bug from all of the sudden, but it just makes sense vs putting a later model duke in.

Quad's going to be a lot more work, of course. Swapping your automatic for a 3.35 Isuzu and going to the later 110 HP Duke would be simpler and easier.

What do you want the car for? Do you really want just a commuter? Do you want a hot rod commuter? Do you want to do an engine swap purely for the pain involved?

[Blue Shift]

Yeah, I can accept the concept of crack prone heads. FWIW, the duke is notorious for the very same thing (my 90' 2.5 has a badly cracked head), so I guess that's an even trade. Do you know what years they equipped the HO's with the factory underdrive pulley? Can I pick up a 92' HO motor and box and have all the best shit (aside from W41, not even going to try)?

After the 3.4 DOHC swap, I have a fairly realistic concept of the energy and time involved, and what to expect. Ain't going to be a month long project. It's been on my mind to completely go through my poor, neglected first car and defux0r all the issues due to neglect anyways, so this would be a good opportunity to do that. The car has sentimental value, otherwise I wouldn't bother. I guess I'm indeed out to make a hot rod commuter - something that'll turn pretty good mileage and is easy to live with for an hour at a time, but outperforms stock. Beating the stock 2.8 in the performance department, while beating the duke in the mileage department will do. Oh yeah, did I mention swapping to a manual will take care of that stupid torque axis mounting system I've come to despise?

[Fastback86]

Yeah, get ready for some head crackage. My dad's '92 Grand Am cracked the head around 100,000 miles, but he doesn't drive it all that hard so that probably helped it last. Get the two-piece timing cover as well, it will make any work you have to do in there - like changing the water pump - much easier. Other than those two things, the motor has been solid. Granted, the head cracking is kind of a big deal, but still, the car is 17 years old and in great condition.

[befarrer]

My first Quad 4 motor had 326,000KM on it, had the original head too. I spun a rod bearing after 10,000KM while reving it near redline on the highway, it burned no oil either. When we took it apart, it had about 1 thou wear on the cylinders, and the crank bearings were in good shape for wear. I think I spun a rod bearing because of the oil I was using, I later heard that it has history of foaming up at high RPM.

My current Quad 4 (1991) had 279,000KM on it, but I rebuilt it completely before installing it, I could have gotten away with just polishing the crank as it was still within spec, but I decided to spend alittle more and undersize it, the cylinders had .5thou wear, so I used the same pistons, the head (086) was cracked, but not leaking coolant, but an 88 head (the crappier ones) fell into my lap that was fresh from the machine shop and complete with a gasket set for the same price as a gasket set, so I put that on.

I had mine at the track last year, and ran a 15.08 at 91MPH. My launches suck, and my headlights were on and up, my autocross setup wheel allignment didnt help either (+.5" toe out front, +.25" toe out rear). I have gotten 41MPG (Canadian) on the highway with my 92 Getrag with the 3.92 gears doing 70MPH.

If you were to get a motor, get a 90 or 91, a 92 I think is the same internally, just lacking the underdrive pulley, and possibly the huge exhaust manifold.

[Blue Shift]

Ok, quad guys, I found a whole 1994 Quad 4 HO in the local yard here complete with box. Oil looks ok, and box goes into all gears more or less... Going to see if I can snag it in a couple weeks if its there during the half off sale. If anything, it has all the wiring and parts. I imagine this is one the 175HP motors? Down a bit from the 91-92s? I've read that the 95's suck since it was during the transition to the 2.4.

[p8ntman442]

94 is good.

grab it and go. I can supply the wiring schematics to make it run, you will have to figure out gauge interface.

[Blue Shift]

I hope that motherfucker is still there on half-off day. If so, I plan to grab the engine, box, wiring, and ECM. Hopefully I can build it all up on a cradle and pre wire and plumb everthing.

So what's the deal with the chain tensioner? Do they sell only the redesigned one nowdays and it's a nonissue? I plan to buy premium gaskets, especially the head gasket, but is there anything else to seek out to build a solid, reliable motor? Going to be a sporty commuter, so reliability is what I'm going for, though I'm tempted by the ~250 dollar set of chro-mo H beam rods...

[p8ntman442]

Dont buy new rods, thats retarded for a commuter.


Felpro gasket seets on epay can be had for ~$50 the only gasket the set dosent include is oil pan.

Im not sure on the chain tensioner, but I dont think there is a big issue with them. I will recommend seeking out zppr performance on the q4forums for a lightened stock flywheel and +/- 2* cam gears. that will give you some fun factor with the rebuild. try to grab a 91-92 ho exhaust manifold, or port the 94 aas far as possible.

add 75 wet shot and call it a day.

[The Dark Side of Will]

I have a W41 exhaust manifold for sale. Not sure how it fits in the performance hierarchy, as I thought it was the same as some other year.

Get it out of my shed.

[p8ntman442]

Will, my 93 scx manifold outlet is dinky, i thought the w41 cars were the same manifolds but only the early ones are good.

[The Dark Side of Will]

Give me some identifying information and I'll check it on mine.

[p8ntman442]

I dont have any. But you can easily tell by looking at it. If its impressive, thats good, If it looks really restrictive, thats bad.

[Nashco]

Will, my 93 scx manifold outlet is dinky, i thought the w41 cars were the same manifolds but only the early ones are good.

Yup...92 SCX/W41 = Good, 93 SCX/W41 = Not as good.

Bryce

[Blue Shift]

I'll consider myself lucky if the drivetrain is still there, and even luckier if it's still whole this weekend. With some help, I should be able to grab that bitch and put it aside to build up on a cradle till I can get my other car down here. Going to go check on like Friday to scout it out. I found myself an entire clutch/brake pedal assembly, the master cylinder, and clutch line all the way back, so aside from the shifter, the wiring mods, and the tranny, that part should be mostly covered.

I assume that the 086 heads are half the difference between the 91-2's rated 180 HP and the 94 rated at 170? I'm pretty much planning on getting a replacement head when I go through this thing so I'll be looking for an 086. I didn't know that the exhaust manifolds were that different, other than the style differences between LO and HO. Does the 94 have the same cams, or did they take the piss out of them for driveability later on too?

Oh yeah and an actual tech question since I'm here - looks like replacement HO pistons in overbore sizes are difficult to find. All the usual parts houses seem to have the same piston for the Vin A motors and the LO. In the case of the 3.4DOHC it looks like they used the domed stick spec piston for all, but to me it looks like the 9.5:1 LO pistons are all that's available? Any ideas?