Roadkill's 1983 Chevy Z28 - (Work Starts on Page 5)

[Roadkill]

Not alot of time so here's some pictures to some up just some of the work that's gone on today . . .

Thanks to Titsy and especially to Shiftini.

ROADHOUSE !

[Andy]

THAT IS AWESOME!!!


Nice work guys!

[Incursus]

Quoting: Roadkill

Thanks to Titsy and especially to Shiftini

What about me?
For keeping your sofa company and your fiancée warm.  

[FUBAR]

Nice!

Leave it Red & Black

[daveyboy]

[ianjpage]

looking sweeeet

[Titsy]

Summit have shipped, no word from Spohn yet...

[Roadkill]

On a sidenote I suspect the Hood is now actually slightly LIGHTER for the scoop . . . .

Weighing up what was cut-out to what was added I certainly don't think at this point that it's heavier.

Admittedly I've got to do a little bondo-ing to smooth it out a little but even then I reckon it won't be far off of the stock fibreglass weight . . . and certainly lighter than the steel bonnet.

All in all I'm happy I opted to cut-up the original fibreglass one in the end - made life a lot easier.

[Roadkill]

Following on from my front pulley / balancer saga i've found several mentions of the LT1 being internally balanced at the front and externally at the rear . . . .

Quoting: A Guy replying to another guy on another forum . .

The motor is a mixture of internal and external.

By definition, an internally balanced engine has a neutral balancer and flexplate. All of the balance is internal. Externally balanced engines have weights on both the balancer and flexplate.

The LT1 is a combination. Take a look at this photo:



The crankshaft on the right is an early SBC crankshaft. It is internally balanced, (used neutral balancer and flexplate) but notice the offset flange shape. The crank on the left is an LT1 crankshaft without that offset flange. To compensate for that little bit of weight, the flexplate has a tiny weight welded on it.

So, depending on how you look at it, it could be called either one. Everything from the flange forward is the same. The only difference is the flange and the tiny weight on the flexplate.

Order a flexplate for a 1-piece rear main SBC 350, or an LT1. It will probably have the same part number. The balancer is still neutral, but the flexplate has a tiny weight on it... But to assume that a parts company will call it the "right" name is difficult to say. If your parts suppliers are anything like the dummies here in the US, they probably call it "external" because of the weight on the flexplate.

Put it this way... if you order a flexplate and it is neutrally balanced, its the wrong one. Call back and order the other one with the weight on it.

[philoldsmobile]

Quoting: Roadkill

All in all I'm happy I opted to cut-up the original fibreglass one in the end - made life a lot easier.

definitely was a good move - the bond between the fibreglas scoop and fibreglass bonnet is going to be far better than fibreglass to metal too.

[Jamieg285]

Quoting: Roadkill

Following on from my front pulley / balancer saga i've found several mentions of the LT1 being internally balanced at the front and externally at the rear . . . .

I'm not sure I hold to that theory, and would investigate further.

My 400 crank also has the offset flange like the one in the pic, but that is externally balanced.  I have also never seen a balancer with a weight on it.  The 400 balancer does have a notch taken out of it, and the flywheel has a weight.

[philoldsmobile]

i'd work on the theory of go with what it had before...

I can relate first hand what happens when crank balancing is wrong - even if you cant feel any vibration,it may be there - harmonic vibration is wierd

[Roadkill]

Quoting: Jamieg285

My 400 crank also has the offset flange like the one in the pic, but that is externally balanced

That's because, apparently, the 350ci's are internally balnced whereas the 400ci's are externally balanced . . . . The LT1s are kinda both.

http://www.carcraft.com/techarticles/ccrp_0808_383_stroker_small_block_chevy/stroker_cranks.html\" target=\"_blank\" rel=\"nofollow\">http://www.carcraft.com/techarticles/ccrp_0808_383_stroker_small_block_chevy/stroker_cranks.html

Have now found various clues that point towards non-critical balancer fitment.

Both Summit and Jegs do bolt-on replacements with no mention of balancing required, nor the original pulley needing bolting over the top.

Summit even state, that when you do a search, that the SBC's harmonic dampeners are "neutral"

See balance style:

http://www.summitracing.com/search/Department/Engines-Components/Section/Harmonic-Balancers/Make/CHEVROLET/Engine-Size/5-7L-350/Engine-Family/Chevy-small-block-Gen-II-LT-based-engines/Year/1993/Model/CAMARO/?Ns=Rank%7cAsc\" target=\"_blank\" rel=\"nofollow\">http://www.summitracing.com/search/Department/Engines-Components/Section/Harmonic-Balancers/Make/CHEVROLET/Engine-Size/5-7L-350/Engine-Family/Chevy-small-block-Gen-II-LT-based-engines/Year/1993/Model/CAMARO/?Ns=Rank%7cAsc

[Roadkill]

MINI UPDATE

I'm running around in circles trying to find the best solution to my balancer issue.
The good news, it seems, is either way I don't have to pull the motor to get it all balanced.
The bad news is finding suitable balancer to fit the keyed hub I need to get . . . but worse still using it in such a way so I can get successful timing light readings from it as, the LT1 has no timing pointer and I'm running non-FI so need one !!



On a sidenote I've been speaking to peeps regarding an ideal Cam (for when it happens) and am making good progress with that.

Side, sidenote.  I'm currently working on the hood.  Have cleaned up the matting Shifty laid down and have added another generous coat of P40 as there were some weak points near the rear where the matting was restricted.

Weather permitting I'll have a sanding fest tonight when I get in and apply another, thinner, coat of P40 then sand down tomorrow ready for filling.

I hope to get the hood back on as soon as possible but am considering removing the hood rams as they've always been too aggressive for the fibreglass hood and now it's even lighter I'm wary of the hood getting stressed.

Plus removing the rams saves weight and I want my 2" drop-spindles !!

[philoldsmobile]

might be worth speaking to gas strut engineering in Bedford, give them your rams, and tell them to replicate it in an adjustable. you then just bleed gas out until they are the right tension.

hood props are just nasty, and probably almost as heavy..

[Roadkill]

Quoting: Roadkill

On a sidenote I've been speaking to peeps regarding an ideal Cam (for when it happens) and am making good progress with that.

Have been recommended the GMPP Hot Cam :

http://www.summitracing.com/parts/NAL-24502586/\" target=\"_blank\" rel=\"nofollow\">http://www.summitracing.com/parts/NAL-24502586/

Not on the list yet, but more for future reference.

[Roadkill]

I really need to get some piccies of the hood up . . .

Any hoo . . .

Update on Hood :

Hood now has scoop fitted and last night (PhilO &) I reinforced the scoop as I felt it was a little flimsy . . . It's now more than twice as rigid.
I've also P40'd the join lines, and P40'd the transition between scoop and hood and filled the old indents on the Z28-style hood.
The Hood's had two filling and sanding sessions and last night I primered the area to see how far I was off still . . . . much to my surprise it actually looks quite close and I think about 90% of the remaining issues will go with some high-build primer . . . the rest will see a little more filler.

Update in general :

The 3-Point harness are in the car . . albeit not, exactly fitted . . .

The front brake line bracketery is all painted, finished and re-fitted.  I also re-refitted the front S/S flexi's last night using all new hardware . . . thus, the brake "circuit" is now complete.

It's my plan to fit the last few retaining clips to the front brake lines and then re-fit the wheels and lower her down again . . . then I can re-fit the re-assembled front end . . . .

[Titsy]

Quoting: Roadkill

I'm running around in circles trying to find the best solution to my balancer issue

More Circles for you:

Note that there is (or should be) a key (or is that for the cramk gear?):
http://shbox.com/1/engine_front_diagram.jpg\" target=\"_blank\" rel=\"nofollow\"> [img]http://shbox.com/1/engine_front_diagram.jpg\" border=\"0\"  alt=\"\" width=150>

Note item 77:
http://shbox.com/ci/balancer_hub.jpg\" target=\"_blank\" rel=\"nofollow\"> [img]http://shbox.com/ci/balancer_hub.jpg\" border=\"0\"  alt=\"\" width=150>

[Roadkill]

Quoting: Titsy

Note item 77:

That's understandable as the balancer itself is weighted in order to neutrally balance it.
That bit, I'm sure I've sussed.

Quoting: Titsy

Note that there is (or should be) a key (or is that for the cramk gear?):

That goes against everything I've read so far . . . the 96-onwards have them AFAIK but not earlier - there was no accomodation for a keyway on the hub, only the crank snout - hence the common upgrade like :

http://www.thunderracing.com/shop-by/vehicle/1993-1997-LT1-F-Body/Engine/Keyed-Crankshaft-Hubs/\" target=\"_blank\" rel=\"nofollow\">http://www.thunderracing.com/shop-by/vehicle/1993-1997-LT1-F-Body/Engine/Keyed-Crankshaft-Hubs/

[Titsy]

okies

[Roadkill]

Pictures :

After some P40 (fibreglass) :



After the first Fill :





After some strengthening . . . :



The hood now sits back on the Camaro in Red Oxide (pic to follow) . . . She needs final finishing but is 95% there.

I needed it back on so I can progress.

[FUBAR]

Looking good m8

[ianjpage]

[Andy]

Ghost!

[Roadkill]

Progress is steady.

Thanks to Titsy for putting in some serious hours over the weekend to get some wires back in the car.

I'm still running around trying to sort the balancer issue I have and, just when I thought it was sorted, there's another variable - my new alternator bracket sits the alternator forward meaning none of the previous options will work without shimming.

So I'm opting to keep my original crank hub but get a keyway machined into it so I can use a woodruff key to ensure correct timing if ever it needs to come off.

Instead of a after-market replacement Balancer I'm going for one from an early C4 Vette - this'll not only line-up my pulleys again but, as the Vette Pulley is alot thicker, should (hopefully) provide a nice smooth area to which I hope to add timing tape to because, currently, the LT1 has no timing marks nor a timing tab and pointer !!



I'm hopeful, though . . .