I've been doing some searching about cams for the last couple days and it seems that a lot of people love the ZZ4 cam...will it be a good choice for my application?

It'll be going into a 305 TPI 5-speed with some of the basic mods(free mods, K&N, full exhaust). I want something moderate - nothing too conservative that it won't make enough of a difference, but I also don't want something too aggressive that could hurt other aspects of the car/engine. It will be going in with a set of heads as well, but I was planning on deciding on those after I sort out the cams. My goal for the car is mid 13s (this'll be after the aforementioned stuff plus quite a bit of suspension mods - shocks & struts, Eibach Pro-Kit, and so on, as well as BFGoodrich KDWSs) after I'm done with the heads and cams. Will the ZZ4 be enough to get me there?

More importantly, what kind of gains can I expect from the ZZ4 in terms of HP and 1/4 mile times? I've heard that it does a great job of improving HP and torque across the entire powerband, which is exactly what I want.

Finally, would it be a good idea to replace the springs and rocker arms? Any suggestions on those?

Thanks a ton for any answers on any of these questions, I realize there are quite a few of 'em...

 

The ZZ4 cam is a GREAT all around cam. Alot of people on these boards will tell you that it's a small cam, but it's not. It just makes it's powerband right where the TPI likes it, low to mid range.


The idle of the ZZ4 cam in a 350 car is not noticeable from stock. In a 305 , it becomes a bit more cam, since the engine is smaller in size....however, with headers, and a good exhaust I don't think it would be a problem. NOTE......with a 350 and a ZZ4 cam, it runs pretty nicely on the stock chip.......I REALLY Think that you'd GREATLY benefit from burning a custom PROM in a 305 w/ the ZZ4 cam.

As for springs, you WILL HAVE TO change the springs. And unless you want to pull the heads to have the spring pockets machined for a bigger diameter spring, you'll need springs that will bolt in. Go to www.competitionproducts.com Email their tech support, they will hook you up with a set of spring, locks, retainers that will BOLT in to your heads, and keep valve seal to retainer clearances at a safe level.

Do a web search on "seal to retainer" clearance on the web and READ READ READ.....I could explain it here, but I think you'll get ALOT more out of it if you read it for yourself.


Mids 13's might be optimistic on a mild 305, and the suspension mods you listed don't help hook the car up at the track.

Header, exhaust, ZZ4 cam, ported plenum, free mods, some boxed or tubular lower control arms, and an airbag in the right rear coil spring WITH A GOOD TUNE, I would GUESS that with a good 60ft time, you could get low 14's out of it.......possibly 13's.

I've heard of plenty of 305's going faster, just haven't seen them myself.

Look in my sig......I've only run my IROC 4 times down the track, and that was before I did a major tune, added header and exhaust, good wires, good ignition, and at the time, my tranny would not shift into 3rd at WOT when manually shifting......and traction was a JOKE.....my best 60 ft time was a 2.2.....

I have no doubt, that with a 1.9 60 ft time, my current combo will run a LOW LOW 14, if not a high 13, ESPECIALLY since I'm ditching the slushbox auto for a World Class T5......draw your own conclusions from that.



HTH

 

The ZZ-4 cam in 305 has an agressive sounding idle but idles smoothly at 750 RPM and pulls strong from 1000 RPM to 5000 RPM. My 305 is running a stock 1988 chip and it works well. On the chassis dyno my stock chip had an almost perfect air fuel ratio at WOT and the spark curve was also close to perfect for what my car wanted. We did burn some different chips that played with the fuel curve and spark curve but ended up going back to the stock chip in the end.

My car has a completely stock rear supension and street tires has turned a best 60 FT time of 1.9 seconds and a best ET of 13.53. (Lots of practice at launching the car) My engine modifications are in my sig, it is possible to hit your expected goal with your 305.

The previous post mentioned that you will have to upgrade your valve springs to run the ZZ-4 cam.

 

NICE numbers on the 305......


My IROC should be a solid LOW LOW 14, high 13 second car once the T5 is in. Then with the addition of the ZZ4 cam, and some PROM tuning ( after the 165 ECM swap ) I'm convinced it'll be a mid 13 second car. AT that point I'm going to concentrate on some other things I want to get done, and I'm now considering going ahead and adding the Vortec heads, and SD vortec TPI intake to the current 350 next Spring, before I start building a 383 / 406 that will eventually replace the 305.

That's nice to see.....I figure with the Vortec combo, ported intake, and some good tuning I could see LOW 13's if not high 12's with traction.

My eventual goal is to break the 11 second barrier in a pump gas, NA, 383 / 406 car, with the LTR setup. In the long run the SR setup is cheaper, but I like the TPI Setup, and with tuning I'm sure my goal is attainable, ALOT of it is in the chassis.


Later

 

Anyone have part numbers on the proper springs required with the ZZ4 on stock heads? Ive had a brand new zz4 cam sitting next to me for months on end now, but I keep getting different answers weather the stock heads can handle that much lift or not. If my stock heads will take the lift with new springs and retainers, Ill throw it in there.

Part numbers would be great!!!

 

CETA said that hes getting a set of heads wich i belive is going to come put cheaper then having the heads ported to match something of the SR torquer heads... I plan on doing the SR heads with my ZZ4 cam swap this summer. it has the springs i need and it also has bigger valves and much improved flowing... with a trans rebuild and a new TC and rear gears i could be hitting 13's. I read around and the ZZ4 cam is an awesome cam. plus i got it for 120 so i think i lucked out. good luck with your car man.