What Makes It An Ho Engine?

[kidcarlo21]

hi everyone, i have a LO engine quad in my 89 ga. i have the o89 head and i just cracked it. should I buy the HO head? or do i already have it?

[Brad97GS]

If you mean that it is an 086 head, then that is the HO head. Certain years used the same head for both LO and HO (though '89 was not one of them...maybe someone replaced the head once already). There are several differences between the LO and HO - cams being the biggest difference. The 086 head is the best flowing of all the heads used... :)

[Matt95GT]

Heads varied mainly by year, not but HO or non-HO.

The other HO goodies:
-cams
-pistons (higher compression ratio)
-larger intake manifold (depending on year, some LD2's have em)
-larger exhaust manifold (depending on year, early LD2's have a 4-2-1 style, newer use same manifold as )
-smaller crank pulley
-PCM (higher revlimit, etc)
-transmission - Getrag 5-speed only

[allshownogo]

could someome tell me whether you can swap a 2.3 ho motor into a 89 4-door grand am le w/2.3 lo a/t? i'm trying to make a hp family sedan. thanks for any advice.

[Brad97GS]

You can, though the HO really won't be that great with an auto trans...the manual tranny is much better suited to the HO engine.

[Matt95GT]

I'm with Brad... an HO + auto would be a poor combination. It will shift before the HO gets into the peak of its powerband.

But yes... it is a direct swap otherwise.

[kidcarlo21]

so is there such a thing as the 089 head? or am i confusing it with the 086 head. i was told that i had the 089 head already, but i could have heard wrong and he actually said 086.? ya i was thinking about changing my quad LO for the W41, but i was told that the stock auto trans wouldnt hold, is that a right assumtion?

[Brad97GS]

Well, not so much that the auto wouldn't hold up to it, but it would be a dog. Actually, I would bet that the W41-auto combination would be slower than the LO, just because the W41 screams above 6000 rpm. The auto shifts at around 6200 IIRC.

There is no 089 head. So either it's an O86 head, or it's an '89 head, which is a 955 (stock for the LO in '89). You can check the number by taking off the Quad 4 IDI cover and looking down in the 'valley' between the cams. The part number for the head is stamped into the head right by the timing chain housing, and the last three digits are the numbers you're looking for.

[Matt95GT]

^Agreed. If you need to run the auto tranny, the HO and W41 are poor choices.

I don't know when the auto shifts, but even the HO doesn't really "wake up" until 5,500 RPM. The W41 would be even higher. That barely gives you any peak of the powerband... I think the car would be slower and have awful drivability. My HO is a dog below 3,000 RPM, and auto's need torque. The LD2's were optimized for use with an automatic, the HO's are optimized for manual only. It's certainly possible, but I think you'll be horribly disappointed with the results.

[kidcarlo21]

ya ok, i checked i do already have, the O86 head. thanks guys. i might be selling the car, but if i dont i would like to keep it and convert over to a manual trans and put a nice blown w41. only time will tell

[Brad97GS]

I like the second option. :) There are some turbo Quads around, but I haven't heard much about supercharged Quads...

[urweak]

theres probably like 3 supercharged quads i heard of, one guy was using the 2.4 head and the GM charger, another was using a charger off the old T-birds, and then another in a achivea i think.

www.the-race-shop.com sells a kit to change your ld2 into an lgo pistons cams and all that junk for like 500-600