northstar engine swap

[Hippie]

I would sure like a V8 in my gen 1 W-body, but the Caddy 4.9L isn't a particularly good engine. Too bad there aren't other V8 options.

 

Geez, just poke a sharp stick in my eye why don't ya' ? The later ones are quite reliable if properly maintained, kind of like a 3.4 DOHC. I did a lot of checking around before I bought mine because of all the negative press I'd heard. I found that the 4.9 isn't the ticking time bomb the 4.1 and 4.5 were, at least not the later ones. I got a '95 which has all the factory fixes ( greatly improved cylinder block casting ), it was a low mile pampered specimen so I'm not worried. But yeah, if you DON'T maintain them......... :bawl:

 

If you REALLY want an easy V-8 for the early W-body it's the only choice. Hell, GM even built some 4.9 Lumina test mules, from what I heard they were well received but the project got axed. Unfortunately there is NO aftermarket and most of the people that mod them try to get more high RPM HP, these are NOT high RPM motors, they are low RPM torque motors, set your car up to take advantage of that and you'll do fine, try to spin 'em like a 3.4 and they'll blow. I'm an old Pontiac V-8 guy, I learned to love torque over HP for a street car a long time ago. For 1/4 mile I'd build a Series II L67 but for a fairly cheap and fun street car I think the 4.9 is a good choice. It better be... I'm stuck with it now ! :shock:

[GnatGoSplat]

I think the later 4.9L's may be fairly reliable if you drive them like a grandpa (since it's old people who mainly owned the 4.9L cars). Drive it like some of the young guys on the forum drive their 3.4's, and it would likely self-destruct in no time!!! Actually I'm sure they're not that fragile, just not much power from an engine that size. Even the TPI intake manifold for it (used in the Allante) is nearly impossible to find.

 

But, it is the ONLY V8 option for us right now.

[Hippie]

Drive it like some of the young guys on the forum drive their 3.4's, and it would likely self-destruct in no time!!!

:shock: No argument on that one !!!

 

Actually I'm sure they're not that fragile, just not much power from an engine that size. Even the TPI intake manifold for it (used in the Allante) is nearly impossible to find.

 

But, it is the ONLY V8 option for us right now.

 

True, if you just look at HP they aren't very impressive, in fact it's pretty depressing. However it has the potential to make pretty decent torque over a fairly broad range and torque is what accelerates the car. The Sequential Port Injection on the later ones actually works pretty well and the manifold flows well. They are a "square" motor, the bore and stroke are equal, 3.623 X 3.623. That's a pretty long stroke for a 299 CID motor. The peak torque is only factory rated @ 275 but it comes at a fairly low RPM (hence the low HP numbers) and it's a fairly broad flat curve, that means strong throttle response at just about any RPM. With some intake, ignition and exhaust tweaking and careful selection of converter and gearing it could be a pretty decent performer in a light car. That's what I'm banking on anyway and past experience with Oldsmobiles and Pontiacs tells me I'm on the right track. I hope to be able to put my money where my mouth is by this fall........... Too bad it's been out of production for 10 years.

[GnatGoSplat]

Sounds good. I do like that it will sound like a V8. No offense to anyone here, but I've heard many W-bodies with exhaust, and it doesn't matter to me what you do to a V6... it still sounds like a wimpy V6 even if it could slaughter a V8 on the track.

I also think those engines can run 87-octane pump gas, so it wouldn't be a bad daily driver if it got decent enough fuel economy.

[Hippie]

I do like that it will sound like a V8.

 

My #1 reason for the swap. 8)