Ok guys, I'm going another route with my ZZ4. I'm adding the hotcam and 1.6 rockers... while it's all out... what stall speeds have you guys had luck with? I've got 3.08's out back right now.... probably go with 3:73's later...any experiences would be helpful!! Wanna get this thing outa the 16's lol

 

I don't have a torque convertor because I use a manual, but I usually leave the light about 2500 rpm and slip the clutch a little to keep the rpm's from dropping.

 

I have kind of been there and done that - 73 vert ZZ4.

Here is my experience:

My 73 started out with the orginal drivetrain -- #matching engine and automatic th 400 trannyw/ 3:08 gears and 27 inch tires. It couldnt get out of its own way!

SO, I added a zz4, had the TH400 rebuilt w/ a 2400 stall an still the car really didnt get up and go .

SO, I mulled over my options. Mod zz4 w/ fastburn heads and cam? Gear change? 5-speed? Big Block?

I decided to change gears to 3:55s. Better, but still not what I was looking for . I considered changing gears again to a 3:73 or 3:90s but I also wanted driveability on the highway, so I left the 3:55s alone.

I ended up putting a 5-speed in place of the auto . Much better. Totally different car...

The difference between a 3:08 and a 3:73 is substantial and should help quite a bit. Not sure on the new cam since my zz4 is stock. I'd be interested to hear what you think of the new cam.

Cheers,

Crunch

 

My 82 has a ZZ4, 3:55's in the rear, and a 2800 stall in the 700R-4 tranny and TCI shift kit.

 

What are your honest expectations AND demands for the car (i.e. - to run 13s, get good gas-mileage, squeal tires for kicks, etc. )?

 

I have a '69 with a stock ZZ4, th400 with a 2400 stall converter and 3.36 gears and I can melt my rear tires from a standstill. No complaints at all as for as that goes. But to get the best acceleration out of the car I have to manually shift the trans, it wants it shift way too early and besides that I hate the fact at 70 mph I'm turning a little over 3k. So I'm getting ready to swap out the th400 and put in a Keisler Tremec TKO-500 5 speed.

Personally I think the ZZ4 has plenty of HP, even better torque and a big wide power band. I'd leave the engine alone. What kind of carb are you running, are you sure it's set up right? What about the exhaust? Is it letting the engine max out. Put the car on a dyno and see what your getting out of it. My car has 278 rrhp and 335 torque. I've got a Holley Street Avenger 670 Carb straight out the box and I'm running Hooker super comp headers and hooker aero chamber mufflers. Sounds really good too. Yeah there's faster cars out there but not near as many as you might think. By the way i have a 2001 C5 auto with the performance rear axle too and I really can't tell much difference in the way these 2 cars accelerate.

Steve

 

Steve -- I did a TKO600 swap last summer. I wanted driveability and good acceleration and the 5-speed is the ticket -- good choice.

You mentioned you can smoke the tires with the zz4, th400 and 336 gears? Are you running the stock tire size? I have the aluminum factory wheels on my 73 w/ 255 60s and no way would it spin those suckers from a stand still w/ 3:36 gears. Also, I had my carb (600cfm Edelbrock) set up at a race shop so I feel confident the set up was good.

So, then I changed to 3:55 gears (out of frustration) and it still would not spin the tires from a standstill. That was when I decided the 5-speed was the only way I was going to get the best of both worlds.

Spinning the tires really isnt the end all be all, but when I shell out big bucks for good parts I expect certain things and spinning the tires (at least a little bit) didnt seem unreasonable.

BTW, I have Jetthot headers 2.5 inch exhaust, dynomax mufflers and MSD ignition.

Even though I had the carb set done professionally, I have always wondered if I should try a different carb/bigger card? Dyno results are probably the best place to start...

Cheers,

Crunch

 

Crunch,

I have a set of Cooper Cobras on the car in 235/60 15. I think that's 26 inches tall so I've got a little lower ratio due to that and not quite as much meat on the road. And they are getting pretty old now...I think about 16 years old but only 5000 miles. Maybe they are getting hard with old age. I know before I pulled the old base 350 out of it there was no way not even close.

Yeah, some of my local Vette buddies are kinda shocked I can smoke them so easy with the th400 is there. One of my buddies has a 73' 454 auto with lots of performance mods and he can't get his tires to spin either...not sure what gears or converter he has but the car just can't spin em. hasn't been on a dyno either..so who knows maybe it just not all working like it should.

And yeah I agree..smokin' your tires ain't all that necessary but dayem..it's just something a muscle car has got to be able to do. There's a pride factor there.

Yeah I'm really looking forward to getting the 5-speed in there...it should be a blast.

Steve

 

Steve -- I totally agree with the pride factor...it has got to spin the tires! With the 5-speed it isnt a problem

Feel free to give me a shout during your 5-speed install. Not many dudes have done the auto-to-manual conversion. Kiesler has great techs but they are very busy.

Are you going w/ hydraulic clutch assembly? I did and went with the heavyduty clutch and pressure plate. My setup is rated at 600hp/600tq (I think) -- I wanted a little overkill. The hydraulkic clutch is real nice, very smooth and easy to operate.

Mounting the hydraulic master cylider took some effort but it wasnt too bad. The instructions from Kielser were poor at best BUT to their credit I think they have rewritten them and added pictures but again, not many dudes do the auto to manual conversion so the instructions may still be lacking in that department.

One other thing. As far as gears go the Tremec works better with a lower ratio set of gears, whereas a Richmond works better with higher gears. For example, Kiesler recommends a 3:73. I have 3:55s and had previously installed them and didnt want to spend the money on another gear change BUT I could use a little more gear, i.e., 3:73 or even 3:90s. Dont get me wrong, the 3:55s are great but I still have some room if you know what I mean. So what I am saying is that you may want to consider changing from the 3:36s.

Best of luck with the 5-speed!

Cheers,

Crunch

 

Hey Crunch,

Yeah, I'm going with the hydraulic clutch, matter of fact I've got a question about that. Where does the master cylinder end up? Is it in plain site? Kinda thought I would want mine not to be so obvious since I show my car and a clutch master cylinder is not the norm in the engine bay of a C3.

I'm going to give the 3.36's a try and see how I like em. Top end sounds nice with 70mph at 2050rpm. And as hard as the engine pulls in first now with the th400/3.36 combo the tko-500/3.36 will be like a 4.36 with the th400. Looks like new tires might not be too far down the road too.

Hey and thanks for the offer about shouting at ya during the install. I hope to be going in with it in a couple weeks.

Steve

 

Getting back to the original issue for a minute (3.08 vs 3.73 gears), I made that change in my car and lowered my 1/4 mile times by about five tenths. Huge difference. Still on street tires.

 

Steve,

The hydralic clutch master clyinder will be undeneath the power brake booster (I assume you have power brakes) and it is completely out of sight -- no worries there. I even managed to mount the fluid reservior over by the washer fluid reservior and it too is pretty much out of sight. My car is in the paint booth and I am headed out of twon until the 26th. When I get back I'll take a few pics of how i did the setup and send them to you.

Cheers,

Crunch

 

Bk how fast can you cruise on the highway before it gets to annoying?What are rpm are you at at MPH?What size tires are you running??

 

I don't feel comfortable cruising at over 3,000 rpm and that is about 60 mph in my case. That is with 255 60 15 tires, about 26.5 inch diameter. So I stay on the roads with traffic lights. More fun there.