69 Z28, 302DZ question - Team Camaro Tech
Engine General Engine Discussion.

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 23 (permalink) Old Sep 6th, 04, 03:56 AM Thread Starter
 
Join Date: Dec 2003
Location: Virginia
Posts: 3
Post

Building a 302DZ engine, questions:
1. Is the 8 inch harmonic balancer for a 350 engine the same as the 8 inch harmonic balancer for the 302DZ engine?
2. Is the Chevy orange the correct color for the DZ engine, or is it different?
3. What is the best brand of engine paint?
4. Should I use the GM 30/30 cam or would you recommend the cam used for the cross-ram?

Thanks,
James

James
rainmann23314 is offline  
Sponsored Links
Advertisement
 
post #2 of 23 (permalink) Old Sep 6th, 04, 05:42 AM
 
Join Date: Apr 2000
Posts: 21,341
Post

Yes, you can use any balancer you want as long as the timing cover tab lines up.

I think Chevy changed the timing covertab and balancer mark locations in '69 when they went to the long water pump set-up but I may be off here. Just be forewarned!!

Use the smallest, lightest balancer you can find for drag-race application and the biggest, heaviest one you can find for road-race endurance application.

The 302 uses the big one as does the 327 Special High Performance engines. I don't know if the 350 used the same balancer as the 302 but I doubt it. BUT they are close enough to use anyway. Now that I think of it, the 350 balancer is the same diameter but not quite as thick???

Yes, Good old "Chevy Orange" is THE COLOR!!

I use whatever engine spray-can paint I can find at the parts store.

The 30-30 cam, (-346), is the only stock cam used in the 302 motor. The "First Design, Off-Road" cam, (-140), was never installed in a stock 302 from the factory. There is no "cross-ram" cam as such even though the -140 cam was generally used with the cross-ram..

Here's the spec's of the two cams:

1. –346 big Duntov or 30-30 solid cam, (346 per GM, 314 per WBR and 304 per Pat Kelley.)/254/254, .486"/.456"net, .486"/.456"net, 114/112. (.030"/.030" lash). (Note: Might be .485"??)..

2. –140, Z-28 First Design Off Road solid, 257/269, .493"/.469"net, .512"/.486"net, 112/108. (.024"/.026" lash).

and for;

3. -754, Second Design Off-road solid cam, 325/262/332/273 per WBR, 112/108, .512"/.488"/.536"/.510". (.024"/.026" lash).

Hope this helps.

pdq67



pdq67 is offline  
post #3 of 23 (permalink) Old Sep 6th, 04, 09:39 AM
Senior Tech
 
Join Date: Nov 2003
Posts: 945
Post

The 8" balancers are the heavy thick ones and you can still order the 68 302 balancers from GM so if you want it to look close, then get one. They are the same size / weight and only the front ribs vary a bit, but they are not seen under the pulley anyways. The 302 also has a unique timing cover for that year that matches the 8 inch balancer in 1969. As for the paint, and regular chevy orange will do but buy a high quality paint if possible. Ask your local engine builders as they always seem to end up with what works best.

As for the 302 motors, these motors are total dogs off the line and don't really work well until they reach high rpm's. Add a crossram to that equation and you'll have a back firing, pop farting, power valve disintegrating slug when it comes to city driving.

One reason was because of the original cams and the long duration. I would recommend a couple of things to you if your building a crossram motor. First find yourself a spare block to build if you in fact have an original(prefer date coded to 69) and install a 350 Forged Crank into the spare block. Now you can save the original and keep it on the shelf as I have done. Build the 350 motor to look totally like the DZ motor with all the right parts and use whatever pistons and camshaft you want. Then top it with some 186 heads and a crossram and you have a stealth looking DZ Motor with 355ci guts and nobody is the wiser.

I have done exactly as described above and run a 355 with 10:1 forged Wiseco pistons, a very healthy Comp Cams EX290 Extreme Solid, and Roller Rockers on GM Performance heads. I topped that with a home made crossram, and surrounded the engine with all the correct original parts. Works awesome and make a ton more horsepower and torque tahn a 302. All this while my original 302 sits on the shelf to preserve it.

Look at my web site if you want further details about the build and the car itself.

http://www.x33d80.com/home.htm
hugger_sixty_nine is offline  
 
post #4 of 23 (permalink) Old Sep 7th, 04, 03:29 AM
Senior Tech
Tski
 
Join Date: Apr 2002
Location: Hartland, Mi
Posts: 123
Post

Quote:
As for the 302 motors, these motors are total dogs off the line and don't really work well until they reach high rpm's. Add a crossram to that equation and you'll have a back firing, pop farting, power valve disintegrating slug when it comes to city driving.
Hugger,

I dissagree - my 302 crossram does none of this and is surprizingly civil on the street. Granted I'm now a Holley 4150 freakin expert but my drivability is great.
14:1 idle
13.8:1 cruise - crossram likes rich cruise
12.8:1 WOT
No popping
No backfiring or farting
No raw fuel eye burning fuel at idle
Never blown a PV
Drive it to work EVERYDAY (when weather permitting)
Ran 12.8 1/4 mile (polyglass tire limited)
Ran 118 mph 1/4 mile (3250 est. = calc. 492 flyHP)
When I first put this thing together it did everything you said except the PV. Initial tune fixed everything except cruise A/F = was just pig rich. Modified the metering block to correct and this thing runs great. I have still not had a chance to get it on the dyno, but ran some pretty good numbers at Milan. I'm going to barrow a set of slicks from my buddy and run it again on the 14th...I'll let you know what she does.
You mentioned a "ton" more HP and torque - are you sure? And this is all with a 7K rev limit!

Tski
Tski is offline  
post #5 of 23 (permalink) Old Sep 7th, 04, 04:09 AM
Senior Tech
 
Join Date: Jun 2003
Location: Tampa, FL
Posts: 957
Post

Tski,

You went a 12.8 at 118? Seems like you picked up some major ponies over your single 4-bbl setup. Let us know when you get that thing re-dynoed. Thx. -Neil
Neil B is offline  
post #6 of 23 (permalink) Old Sep 7th, 04, 02:06 PM
Senior Tech
 
Join Date: Nov 2003
Posts: 945
Post

Craig,

As you know, I have a 355 in mine because the 302 is notorious for being a dogs off the line unless you gear them with 488's. We mounted the crossram using converted 4770 carbs (600cfm) and downed the jets by 5 sizes and the same with the power valves. Because the car is not complete, we did nothing more than run the cam in with a few engine runs after that to get things dialed in a bit. It runs great now but might still be a tad rich. Things will be better when I get it out for a drive and have the chance to dyno it which will happen as soon as I finish the wiring, and the interior. If that happens before the snow flys I will surely post the tuning results.

Right now this motor runs very strong and sounds totally wicked, but the true 1/4 mile tests are yet to be known. All calculations put this 355 near 475+ horsepower with Torque being 450+. If you have'nt heard the engine run, there are three video files on the engine pages of my web site. I said what I said about 302's because I have owned a couple and have friends who all say the claim the same. If you compare a healthy 355 to a 302 with the same mods and a crossram, there is no comparing the two of them. With that being said, I will let you know when I have had it on the dyno, have the carbs totally dialed in, and have ran the quarter. Running 12.8 @ 118 is very good so we will see what my setup runs and will post results. What kills me here is the altitude in Calgary where I can run a full half second slower than most due to air being measured anywhere from 5200 to 8000 feet here depending on the time of day etc.

I have been too busy to complete this car because of my wifes pregnancy and a few late minute add ons, but hopefully an Indian summer will allow me to get it out for a few test and tune nights. All parts are here now, just gotta finish the wiring off and put the rest of the interior back in for the third time. Late parts additions forced me to wait a few weeks. You know how it is when a frame off finishes up right?

Later!

Check out the engine under the mechanical link on my web site. 3 Video's
hugger_sixty_nine is offline  
post #7 of 23 (permalink) Old Sep 7th, 04, 02:47 PM
Senior Tech
Tski
 
Join Date: Apr 2002
Location: Hartland, Mi
Posts: 123
Post

Engines should come last......it's just way to painful to hear them run and not have a seat to to park your butt in

I'm sure your chompin at the bit. You must get it done before your baby arrives....after my wife gave birth to our first my hobbies came to a stand still for the first 6 months....had our second and I still haven't finished a few projects I started...and that was over three years ago

Soooo....get off the computer and get busy!

Later,
Tski

<a href="
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
target="_blank">http://www.wideopenwest.com/~tski/camaros.html</a>
Tski is offline  
post #8 of 23 (permalink) Old Sep 7th, 04, 03:15 PM
Senior Tech
 
Join Date: Nov 2003
Posts: 945
Wink

[img]graemlins/thumbsup.gif[/img] Lauhing my *** off at that one!

Christine was due Sunday, but no baby yet. We went to the hospital today and they said they will induce her Friday so thats when he will arrive if not sooner.

I was in the middle of completing the inside wiring last week when I bought a new set of rosewood dash pieces, new kick panels, and an AM/FM radio which have all yet to arrive. Therefore, can't complete the wiring install until thats done. Once the parts are all here, I can reinstall the gauges, wiring, and button up the inside. Next will be the engine harness, lighting harness, and then it's ready to run. Thats about 2 weeks away if all goes well.

Damn right I am chomping at the bit. Its been driving me nuts since we test fired it and broke the camshaft in. Because I missed my goal of a local show 10 days ago with this car, I said screw it and it will wait till I am finished the interior 100% before rushing it, then I went and upgraded with some new pieces which of course have caused more delays. I have not even gone out to hotwire it which can easily be done and that is as tempting as anything. Nope, I will patienty wait till the interiors complete, and they i'll get the car out for a a dyno tune session.

I just can't take any shortcuts as I plan to have this 100% for the world of wheels in February where it will be debuted. Figured I might as well shoot for trophies with it at least once before I go and blast rubber and dirt all over it. Bottom is cleaned up and looking brand new so the only ride it might get this year is a dyno session and a cruise out for a pictorial or two. Track time will just have to wait till spring unless we get a nice fall. Summer has been cold, wet and Sh*tty here so what hopefully fall is nice.

Nice chatting with you again Craig and keep up those awesome time slips. My turn will come
hugger_sixty_nine is offline  
post #9 of 23 (permalink) Old Sep 7th, 04, 05:08 PM
SY1
Senior Tech
Dave
 
Join Date: May 2001
Location: Michigan
Posts: 2,920
Post

Guys just gotta add my two cents here. I agree with Hugger the 302 CAN be a dog off the line when you consider how most everyone today seems to want to run 3 series gears. I understand wanting to drive the cars daily or weekly, but if you want to wake them up you've got to run more gear. The only way to make a 302 respectible is to get them upstairs and quickly. Gear them with 4.56 or 4.88 gears and drop the clutch at 5,000 off the line they'll run with most anything I've put them up against. Most guys aren't willing to do this today and understandibly so. There are better engines to drag race than the 302, but it is a fun little engine if you wind it up high and don't care how much you abuse it.

On the other hand and I know this is going to be unpopular with most of you, I personally have no use for a 350 except to stroke it. They can be made to run very well and the popularity speaks for itself, but I see it as a compromise by GM. It isn't a great high reving motor and it doesn't produce a ton of low end torque, like I said to me it doesn't offer the best of either world, but can be made to run very well. I just believe there are much better choices, when built will yield much better performance than the 350, depending what you want to do with the car. If I want to build a small block I'd start with start with a 400 block. If I want to run it up high with big gears and have some fun then a 3 inch or 3.25 inch stroke will do that. If I want to make a ton of torque in a small block package then stroke it or just build the 406 if your budget doesn't allow for a stroker motor. Either way I'll be a ton happier than I would with the 350.

I don't mean this to offend anyone, a 350 can be built to run very well, they're just not for me. I like something a little less mainstream and I'd try to maximize the what it is that I want from a motor and that starts with the selection of the bore and stroke. Middle of the road bore and middle of the road stroke in the same motor just leaves me wanting for more of both.

Dave

[ 09-07-2004, 08:01 PM: Message edited by: SY1 ]
SY1 is offline  
post #10 of 23 (permalink) Old Sep 7th, 04, 05:20 PM
Senior Tech
Tski
 
Join Date: Apr 2002
Location: Hartland, Mi
Posts: 123
Post

What other small block draws sooo much attention [img]graemlins/beers.gif[/img]

Man, such a simple question and we all start writing....this is what makes this hobby so cool!

Until next time guys....I'm sure I'll get us started again.

Good luck Hugger....and an early congrats!

Tski

<a href="
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
target="_blank">http://www.wideopenwest.com/~tski/camaros.html</a>
Tski is offline  
post #11 of 23 (permalink) Old Sep 7th, 04, 06:02 PM
Senior Tech
 
Join Date: Nov 2003
Posts: 945
Post

Thanks Craig.....

Dave (SY1) I agree with what you are saying. The reason I went 355 cube was to keep the motor in an original block but build something more versatile than the little 302. (More of a wolf in sheeps cloth approach with all the z/28 peripherals) At least with the right setup you can get 450ft or torque and nobody knows it's not the original DZ motor from looking at it.

I spent the better part of 12K on my current motor and yes it could have been better spent in a 377, 406 or 424 motor but that wasn't what I was out to achieve. Lat thing I wanted was a 383 (belly botton motor) where everyone I have seen falls short on higher revs (their torque motors). I have had a few 355's and have no problem buzzing them the 7200 on a regular basis. If I wanted to go higher in revs i'd build a big stroker with a small crank and wind it to 9500.

Trust me, I have a very good friend that runs SBC race motors and revs well over 10K in his current all motor 900 horsepower small block. He has been side stepping clutches in stick cars since the early 70's and normally launches at 9000 rpm. He has taught me quite a few things about small crank motors and I appreciate where you are coming from.

My next car being built is a 55 Pro Steet for my wife and it will have a lot more cubes in it as that car isn't going to be in the numbers game. I did not want to use a 400 block strictly because of the heads requiring steam holes and making the engine look obvious to those who know motors. This was as much about asthetics as it was practical. As I noted above in my last post, 488 gears for the 302 are a must and many times I have responded to threads telling people how to launch them at 4500-5000. This post is about keeping a Z a Z and making it look original while add a few more ponies. It was also about running crossram motors and what the best cam / piston and head combo is if you have a Z/28 with a crossram.

This one (my RS Z/28) has a healthy 355 in front of a wide ratio (264 1st gear) M22 and 373's. It should launch nicely and if it ain't enough, a gear change will be forth coming. My 302 is all complete and numbers matching. It sits on the shelf. Once again, a topic of love and Craig...you nailed it again. Thats why I love these forums too.

Maybe my buddy will chime in about his most recent engine build for his race car. Sheet metal is the word for his most recent motor.

Sorry to go off topic a bit James [img]graemlins/thumbsup.gif[/img]
hugger_sixty_nine is offline  
post #12 of 23 (permalink) Old Sep 7th, 04, 06:33 PM
SY1
Senior Tech
Dave
 
Join Date: May 2001
Location: Michigan
Posts: 2,920
Post

Hugger thanks for not taking offense to my reply, none was intended. I tend to like things that most people don't. I remember one trip out to Witchita when a guy asked me about my Smokey Ram intake and said "you're not gonna try and use that thing on a street car are you?". I told him sure and he looked at me like I was nuts. You probably get similar comments about your cross ram set up I'd bet. But that's what is neat about having something a little different. I've got to tell you I begin to drool when I looked at the pics of your motor, you've done a great job and a lot of attention to detail like I said before, so I'm not trying to take anything away from it. You were wise to set the original motor aside and save it. Myself I'm too tempted to run them hard and it's just too risky when you consider what they're worth today.

You hit the nail on the head with the 350, it is much more versitale than the 302. The 302 is a great little motor but most people will not be happy with it's lack of bottom and mid range power. Most guys would rather go with something else and I understand that. Many nights back in the 70s and 80s when I drove the 302 cars daily I thought to myself why am I doing this? But then you'd get a chance to really wind it up and it was a lot of fun. Driving a 69 Z/28 through Michigan winters the lack of low end power with the 302 was actually a benefit especially with belted tires! It helped keep it on the road when it was icy out.

I think the reason the 350 is so popular is it has so many applications that it will work in, can be made to run really well and is certainly the most affordable engine to build due to the popularity. The reasons I called it a compromise (middle sized bore and stroke) is probably what makes it so popular as a hot street motor for so many people. Since it is mid-stroke and bore it's easy to build it to go one way or the other for different guys. With the 302 you don't have that ability, you have to build it for top end, which eventually if used hard enough and long enough can get expensive.

I've always liked something different than everyone else so I tend to go looking at other options. However the way your 350 is dressed out there won't be too many others like it out there and that's what I think I really like about it. It looks like the 302, but it'll be a better choice given what you want from the car and that includes gearing and how you intend to use it.

I've seen 350s that really run, I just can't help thinking to myself man image that set up with a 400 block to start with. But that's me.

Hope everything goes well with your new addition to your family and hope it doesn't keep you waiting too much longer.

By the way are we going to have a hockey season this year or not? It doesn't look good right now with a week to the lock out. Looking forward for the Wings to try and redeem themselves against the Flames this year. We dumped Hull and Hasek, two big distractions from last year that should help some.

Dave

"..............what, and get out of aviation??"
SY1 is offline  
post #13 of 23 (permalink) Old Sep 7th, 04, 08:19 PM
Senior Tech
 
Join Date: Nov 2003
Posts: 945
Post

Damn, I forgot there was two of you Michigan boys in this thread. (Go Flames / LOL) Thanks for the comments on my motor, and I have to say that Tski's Xram is as an equal treat to the eyes and ears. We were both going down similar paths since late last year and looks like the crossram motors have worked for both of us. Nice to hear you had a smokey ram in the past. That comment you made about " you ain't planning on using that are you" had me rolling.

As for hockey, who knows. I am enjoying the World Cup right now and hopefully they will find a neutral ground with regards to the cap where the season will be salvaged. Don't look to good right now. Maybe we should start another hockey thread and a poll in Bench Racing. See you there.

James....if there is anything I can help you with for pointers on crossrams just ask. There are some great people on this forum and a fair number of them with crossram experience so fire away with any more questions. For the cam, I would stick to something more modern with quicker ramp speeds and higher lift / duration. That will get you some power but it all comes back to what your going to do with it and what you have for heads, transmission, and gears. Let us know what else you have planned for your car and we can spill some more verbs.

Graeme
hugger_sixty_nine is offline  
post #14 of 23 (permalink) Old Sep 8th, 04, 03:27 AM
Senior Tech
Tski
 
Join Date: Apr 2002
Location: Hartland, Mi
Posts: 123
Post

This is what it's all about......





The company I work for put a lot of money into Milan for repaving......we use it as a vehicle test track. We also get it once a month for goofing around...

Tski
Tski is offline  
post #15 of 23 (permalink) Old Sep 8th, 04, 04:00 AM
Senior Tech
 
Join Date: Jun 2003
Location: Tampa, FL
Posts: 957
Post

Tski,

I gotta ask. How did you go from 270 rwhp (approx. 102-103 mph) to 118 mph in the quarter with a manifold swap?
Neil B is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome