ok, about this time next year I am planning on getting a crate motor I've been thinking bout a zz4 my car has a 305 now what all will be needed for this swap also how long do you think the 700r4 and rear will hold up.

 

Since you are already running a carb, the swap will be easy. But, you will need a new flexplate for the one piece main seal motor (no big deal). The only trick is that there is not a fuel pump mount (no pushrod hole) on the ZZ4 as I remember and I believe that your car will have a mechanical fuel pump. This will require an electric fuel pump to feed it (not a huge deal). As for the transmission. The 1984 700R-4's were some of the "worst", only because they had the 27 spline torque converter. And the converter clutches are known for wearing and the dust is what kills those transmissions. Also, those years have the 7 vane pump. I'd probably upgrade the transmission at the same time (it is easier to do them together), I suspect that it won't last long behind a ZZ4. The rear end will probably be ok for a while, depending on how you drive it. The ZZ4 should make about 330 hp to the wheels in your car (roughly) and the LS1's have been hit or miss at this power level with the 10 bolt. You do have the 26 spline axles which are a little weaker than the later 28 splines were. You could get an SLP take out torsen for $99 and a set of junkyard axles from a 90 and up F-body. That would convert you to 28 spline axles.

Just my thoughts.

Have fun!

 

I think the zz4 comes with the flexplate but the trans is gonna have to make it a year but I wont be driving it maybe 1 day a week or so. no more than 150 miles a month.


oh yea what would be a good trans to put in.

 

I'd do a T56 swap, it's not that hard (I've done t5 and t56 swaps). Or get a 1988 and later 700R-4 to have rebuilt (look for a core from a 1988 and up 350 car, they will shift into 4th gear at full throttle).

My thoughts.

 

how much modding is needed to do the t56 swap

 

A Vortec headed truck motor would make the same if now more power than a ZZ4 crate. It would cost less and with the left over cash, you can upgrade to a ZZ4 sized or prefferably bigger/more aggressive camshaft.

Just compare the cylinder heads.

Trackbird, have you ever seen a ZZ4 motor make 330hp at the wheels behind a 700R4? A completely stock LS1 can't even do that and it's light years ahead of a ZZ4 which wears stock heads designed in the mid 80's...

I think the rear axle will be fine. It doesn't sound like you're going to thrash on the car that hard but the transmission is always suspect when you add extra power. A T-56 swap would definately be a safe swap and it would be very reliable in comparison. Search this board for articles and info on it. Goodluck!

 

Actually, The LS1 in severely under cammed (mine is a 198/200 as I remember).

But, actually, the ZZ3 from GM performance parts in their ZZ3 swap made 307 to the wheels. Add "50 hp" and 330 is probably a close guess.

The LS1 is not the "Holy Grail", it is a nice motor with great cylinder heads (as far as stock heads go), but it can't bend the laws of physics either. I have one, and I like mine, but they only make 345 hp on an engine dyno. That makes the ZZ4 60 hp stronger and I think 330 hp at the wheels is entirely reasonable.

My thoughts.

 

Here's another vote for not getting the zz4 longblock. The zz4 has a good bottem end and gm sells that by itself. Get the zz4 bottom end and use the 1000 bucks you save on a good set of heads. Those alluminum L98 heads flow as bad as any set of small block heads made for the 350 in stock form. I dont' like that tiny little zz4 cam either. Go with a 270HR cam from comp cams at the minimum. It's very similiar to the hot cam, so you could go that route also.

That's my .02

 

That is a good plan. I agree those heads are not the best for power production. I forgot about the short block being available these days. But, due to the restrictive exhaust on these cars, I'd run a split pattern camshaft.

My thoughts.