I am strongly considering doing an engine swap. I currently have a 91 RS 305 TBI. I will be changing it over from TBI to Carb. I am trying to decide on engines and I am strongly considering the 350 HO or ZZ4 and would lke your opinions on the two for my application. I will not be taking the car to the track and it will be strictly a street car. I will most likely only be driving it from about April to November as a weekend cruiser. I am looking for a reliable streetable engine which also makes good power (I 'd like something which could keep up with an LT1 or 2000 Mustang GT just to give you an idea of the power I'm looking for). I am also trying to determine the best bang for the buck, which seems to me is the ZZ4 ( better Crank , better Cam, better rods more HP and TQ for only a few hundred more). Once I decide on the engine I would also like your input on weather you think the Deluxe or turnkey packages in these engines are worth it, I am looking for as straight forward, cost effective and easy of a swap as possible. Thanks in advance

The ZZ4 is 50 pounds lighter, but is far overpriced. The best bang for the buck is to spend the $2185 for a new 12530282, because it's the same as the 330 hp 350 HO, except this is cheaper, and comes with a hydraulic roller cam, and all the stuff needed to run the roller setup. So, you buy this, then do the following: 1) pull the heads, and set them up to accept up to .492" lift, polish the exhaust ports, install #98111 springs from www.competitionproducts.com, then reinstall them with FelPro steelshims. Then replace the cam with the GM "hot" cam. This will get you a bit more HP than either of your proposals, for a bit less money.

Ok I looked into that engine a little after I read your post and I just want to make sure I am looking at apples to apples. I compared the two attempting to get them as close in components to one another as possible and this is what I came up with:

ZZ4 Pn #24502609

350 Pn# 12530282
To get this engine to be similar to the zz4 I would have to do the following:

Engine $2200
LT4 Cam $200
Springs to accommodate new lift Aprox $200
Retainers: $50
Keepers: $25
Intake Manifold: $250
Distributor: $185
Water Pump $100
Flexplate $95
Gaskets Misc parts for assembly $50

For a total of about $3355 and a savings of about $600

My next question is I have never attempted installing these parts. In your opinion about how long would it take an EXPERIENCED person to:

1) remove/ install a cam
2) Install a distributor
3) Put on an intake manifold
4) and do the necessary work on the heads (springs, polishing etc..)

In other words how long would it take get this engine to the point of assembly that the ZZ4 is at out of the crate.

Thanks again and sorry for the long post

i LOVE my zz4, there is a guy on here who dynoed 351 rwhp with a zz4 (carbed, manual trans) so they have some power, again i LOVE mine. the thing you have to keep in mind, you are looking for zz4 power, and yea you can do it a bit cheaper as stated, but then you dont get the WARRANTY, and a zz4 is a very realiable motor, i rarely hear of one having issues unless boost or spray in involved. food for though from a zz4 guy. what every way you go your going to have some fun power from what it sounds like!

That is my main concern a reliable cost effective quality engine which has respectable power. I am not looking for a drag car with 500HP, just something that is fun to drive, has respectable power. I am leaning heavily toward the ZZ4 and have been able to read a little more experiences from people who have actually had them installed. My next venture is going to be looking into carbs and trying to decide what will be best for my application.

I can't help much with your decision. I do, however, have the 350 HO Deluxe. Very nice. Recommended. Pics in my Car Details below.

JamesC

It's your decision, but you overestimated a few costs..Springs, $26, not $200. retainers and keepers: $0, you can use the ones that come with the 12530282. That $750 you save would buy you an awful lot of other stuff.

Ok, I didn't realize that the springs were a complete set. I was judging based on the Comp Cams beehive springs. Also would the Accesory drive system (Serpintine system) from my 305 TBI bolt onto both of these engines? Also I saw this on a website that was selling this engine( 12530282) should I be concerned since I intend on running it with a Carb and my stock intank electric pump?

"NOT RECCOMEND TO RUN THIS ENGINE IN A CARBURATED APPLICATION BECAUSE OF THE LACK OF A FUEL PUMP PROVISION, SPECIAL INTAKE MANIFOLD IS REQUIRED , AND SPECIAL TUNING IS NEEDED TO RUN THIS ENGINE WITH A CARBURATOR TO AVOID DETONATION WITH THE HIGHER COMPRESSION RATIO."

Pull the heads and have the top of the valve guides cut so you get more valve travel. That is the best way to go. So, add head gaskets to your parts list.

Your serpentine system will fit. Just make sure the water pump is for your current application (although the L31 application should be fine as well). The water pump that's part of the "deluxe" HO engine is standard rotation, and won't work with the serpentine system.

I wouldn't worry about that "warning". It's aimed at people that just install whatever and figure it will work without tuning. Hopefully you appreciate that some tuning will be required.