First off, i would like to know if it is hard to change an old style intake to fit centerbolt heads (i have a zzz motor with aluminum l98 heads). also, is everything i would need just intake, carb, feul pressure regulator...water neck? bracket for tv cable? anything else? its almost impossible to find centerbolt head intakes used, and i dont have a lot of cash to drop. my distributor got all messed up, so i got an old school one, changed it from vaccum advance to mechanical, got an msd box in, and now i find out theres no way to get it in the computer, so it wont start. going carb would save me time (and money if i sell all the tpi components). so basically i gotta know each part i need and if i can modify an intake easily. and also, a couple basic questions, like benefits of vaccum and mechanical secondaries and electronic and manual chokes; and what size and manifold would work good on the street for the zzz motor? and even if any of you know if i can get that old distributor hooked up to the computer somehow.

 

Don't get caught in this "centerbolt" intake trap - that only applied to iron heads, and is a horrible way to identify the intake manifold required. The aluminum heads have the '86-earlier intake manifold bolt pattern, so you don't need to modify the typical aftermarket intake manifold to fit them.

Regarding your distributor, you said you "changed it from vaccum advance to mechanical". How exactly did you do that?

Regarding your other questions: You'll need a different thermostat housing, 45 degree type, and shorter throttle cables. Vacuum secondaries are good for tow vehicles - are you going to be towing with this car when you're done? Electric choke is much more convienent, typically. An Edelbrock RPM or Weiand Stealth should work fine, some people seem to like the Holley Street something or another (never had any direct exposure to it, personally). You basically don't need to hook any of this up to the computer - you could rig up an external TPS and keep all of the sensors except EGR hooked up, but why would you want to?

Of course, getting a new computer-type distributor would be a lot cheaper and easier.

 

five7kid is right about the intake.I got confused about that when I first got the zz4.I have a 650 dp and it is perfect.I had a 750 and it was way to much for the zz4.Gm uses it to get the highest dyno number but no matter what we did it ran rich and throttle response was way better with the 650.I made 271rwhp and 368rwtq with nothing else done.Be advised that the stock tpi unit and shorty headers like edelbrock will result in less power.I have 1 5/8 true duals.My friends with montes only run 248-256rwhp with shortys.If you want get a performer rpm makes another 10hp and 5lbs over zz4 intake. The zz4 intake is just a performer.Peak hp will go up maybe 200rpm and tq likewise.You can use a 750 but use vac. sec. if you do and it will need to be tuned and jets may need to be changed.The 650dp needed nothing.Just adjusted the float level and idle and it was perfect.Took me and my brother 10 min.

 

yea i was trying to go for a 650 dp also, or maybe a 670 street avenger if i bumped into one. my buddy whos guiding me with the car and the work is very fond of holleys bcecause he says they are simple to adjust, work on, and rebuild. what i meant with the distributor was it was a vaccum advance, but we just set it up as a mechanical advance. i could go back to vaccum though, since now the tpi setup wont get in the way. im sick of all this computer crap and injector/sensor problems. so much easier without all of it.
so heres the list...intake, carb, air cleaner, 45 degree thermostat, shorter throttle cable, and feul pressure regulator? thanks so much guys.

 

The TV and perhaps cruise (if you have it) cables as well.

Don't forget coolant hoses and fuel lines. Some wiring changes.

 

no cruise control, but i do have the tv cable...i would need a shorter or longer one? would i need a new waterneck?

 

Shorter. It doesn't have to go as far as the TPI cable needs to go.

AFAIK, "thermostat housing" and "waterneck" are the same thing.

 

so i was thinking a 180 degree thermostat. i already found an intake (performer rpm polished for 50 bucks off a friend) which has a housing. he has a 770 carb as well, but i think that is too big for my application. so now i need a carb, t-stat, regulator, feul lines, and the cables.
i still cant decide on vaccum or mechanical secondaries. thanks so much for helping me through this guys.

 

If he will let you.Is this a close friend? Try the 770 and see if it works.If it doesn't get a 650.Shouldn't take more than half an hour.

 

Yea, this guy is a good friend. But i found a 700 cfm dp here on tgo in the classifieds. i think i might go for that. its 4778.

 

Could work.I was thinking about a 700DP myself but I didn't want to go through the hassle after the 750DP.I knew a 650DP worked.When you get the carb please tell us how it works.I really am wondering what is the perfect carb out of the box for a zz4.Get some dyno numbers on that puppy.The rpm intake should help to.
A little side note.This is something that happened to me but I could have just gotten a badly built one.Demon 650zz4 carb ran like crap.Ran so rich it wasn't even funny.Hole car smelt like gas and through black smoke like crazy.Your on the right track.Keep it simple.

 

mines actually a zzz which is quite a bit different than your zz4. mine is the same as the zz1 as well. aluminum l98 heads, 235/235 .480/.480 cam, 9.8:1, 345/380 with 750 dp, headers, and exhaust with mufflers.

 

zz3. They must have come with a 114 lobe seperation or more to get away with that duration.How does it sound at idle? what do you rev it to?

 

max recommended rpms is 5800, i could never get it to idle right with a stock chip, put it that way. another reason for this conversion.

 

Your going to love it once you put a carb on and get it all tuned.Probably gain20-30hp and little or no loss of torque.Did you have the stock TPI on before or was it moded with runners and baseplate?I have seen guys run only 235hp at the wheels on zz4 with a stock tpi unit.Its a huge difference.
If you had a stock unit im guessing as high as 40rwhp.The stock tpi unit can't flow well after 4500,but I bet you know this already.

 

oh trust me i know. not just the stock tpi, but from the 305. stock plenum, stock runners, stock base, stock 305 injectors 19lb i believe, but a 2x58 throttle body. i bought this car from a nut job. good thing the motor only has like 25k on it.

 

I am so sorry!!!!!!!!!You are going to grin ear to ear when it works.Maybe 50rwhp.I bet your only making 300 at the crank.

 

you can only imagine whats going through my head right now. not to mention i sold the throttle body alone for 225. the polished rpm intake, 700 dp, and feul rails and fittings only cost 250. and look how much more i can sell now. and get faster and easier at the same time. i feel dumb for not thinking about this earlier.

 

Just don't expect better gas mileage. What are you getting know I get 12mpg with my foot out of it.

 

i was getting like 14 on a bad tune but i drive pretty light.

 

Expect 10-13mpg. Thats one of the reasons when I put the 8.5 out of the gn in I left the 3.42s in.Might have gained 1mpg,but really the traction was so bad I couldn't even launch the car.Now I have full suspension and I run around with mt drag radials or I spin till 40mph from a start with 255/60/15 radial ta's.

 

i have 275/60/15 radial t/as and 3.73 gears. im expecting the same problem, lol.

 

ok, so after i get off work today were at least gonna get the tpi of and put the new manifold on, just make sure we dont bump into any other kind of problems, and save time later when i actually get the carb and swap parts. hopefully all goes well.
i also sold the maf for another 80 bucks. im already in profit and have not even gotten to the tpi itself yet or the computer.

 

im looking to swap mine over too. i will be using a 650 dp and an hei dizzy with an incap coil. the intake i think that was recommended to me is a holley street dominator. but i will have to see what all comes about of this motor.

also where can i get a shorter tv cable? and is that the only cable that i need that has to be shortend? where can i get the bracket also?

 

quick update. entire tpi is off. intake, tstat+housing, distributor, msd box, is all set up now. the list is getting smaller. im down to carb, air cleaner, tv cable, coolant hose (waternexk is at a much different angle than before), feul lines, regulator, and throttle and tv cables. hope im not missing anything. if anyone remembers something, itd be cool to chime in. ill take some pics too