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 Back in a Formula Again 
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Joined: Wed Sep 03, 2014 8:59 pm
Posts: 220
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Post Re: Back in a Formula Again
My new Lunati Voodoo cam was on my doorstep tonight when I got home. The lobes on this thing are visibly more aggressive than the old cam I was using.

Image20180704_192857 by Shane Hewitt, on Flickr


I stuck it in the old block and set about confirming all the measurements on the cam card. All checked out exactly.

Now it was time to install it for good in its new home.........& I've successfully completed my first cam swap on a small block Chevy with the intake manifold and lifters still in place courtesy of the LS lifter buckets I installed a while back!

Image20180704_201916 by Shane Hewitt, on Flickr

Currently sitting here running simulations to decide what intake centerline to install this thing at. Its looking like 2 deg retarded in the 108 deg intake centerline is going to be the winner.....I'll ponder it overnight.

Goals for tomorrow are to set the intake centerline & set the valve lash before I head to work. With any luck, I may be able to get this thing dropped in the car this weekend.


Wed Jul 04, 2018 9:20 pm
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Joined: Fri Apr 15, 2005 10:29 am
Posts: 72
Location: Milton
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Post Re: Back in a Formula Again
That is brilliant!

These hoses are no longer available through GM or aftermarket?


auto_god wrote:
So here is a situation most of us have been in.

What do you do when your almost 30 year old & brittle formed vacuum lines break on you? You can't just go to GM and get a new one anymore.

Image20180703_191433 by Shane Hewitt, on Flickr

You fabricate your own! I measured the old vacuum line at 5/32"......I suspected a 3/16" line would make a nice snug fit in the couplers so I stopped by the local parts store on the way home tonight & picked up a 4 ft long length of brake line.


With a little time and patience, me and my tube bender came up with a nice solution to my vacuum hose issue!
Image20180703_193449 by Shane Hewitt, on Flickr

Image20180703_195319 by Shane Hewitt, on Flickr

Not only will these lines never go brittle and break on me again, but given that I'm fabricating the new lines I can route them as I please in a less intrusive, more cosmetically appealing way than the originals were.

Image20180703_195619 by Shane Hewitt, on Flickr

Image20180703_200130 by Shane Hewitt, on Flickr


Thu Jul 05, 2018 2:38 pm
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Joined: Wed Sep 03, 2014 8:59 pm
Posts: 220
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Post Re: Back in a Formula Again
I honestly didn't inquire at the dealer or look aftermarket. This solution cost me $8 & I didn't have to wait for days or weeks on delivery.

chevypower91 wrote:
That is brilliant!

These hoses are no longer available through GM or aftermarket?


auto_god wrote:
So here is a situation most of us have been in.

What do you do when your almost 30 year old & brittle formed vacuum lines break on you? You can't just go to GM and get a new one anymore.

Image20180703_191433 by Shane Hewitt, on Flickr

You fabricate your own! I measured the old vacuum line at 5/32"......I suspected a 3/16" line would make a nice snug fit in the couplers so I stopped by the local parts store on the way home tonight & picked up a 4 ft long length of brake line.


With a little time and patience, me and my tube bender came up with a nice solution to my vacuum hose issue!
Image20180703_193449 by Shane Hewitt, on Flickr

Image20180703_195319 by Shane Hewitt, on Flickr

Not only will these lines never go brittle and break on me again, but given that I'm fabricating the new lines I can route them as I please in a less intrusive, more cosmetically appealing way than the originals were.

Image20180703_195619 by Shane Hewitt, on Flickr

Image20180703_200130 by Shane Hewitt, on Flickr


Thu Jul 05, 2018 4:06 pm
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Joined: Wed Sep 03, 2014 8:59 pm
Posts: 220
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Post Re: Back in a Formula Again
Made good progress yesterday.

ImageAA6F68FA-6FE3-46F5-8DE4-FE1B0284905E by Shane Hewitt, on Flickr

If I can get the last 2 bellhousing bolts in and the headers back in today I'll be satisfied......everything else will go pretty quickly after that.


Sun Jul 08, 2018 7:48 am
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Joined: Wed Sep 03, 2014 8:59 pm
Posts: 220
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Post Re: Back in a Formula Again
Well she is up and running again, but not without an evening of "Uh oh!" going through my head.

Monday afternoon I progressed to the point of first start up, which it did with very little effort. Much to my alarm though oil pressure was considerably lower than what I was anticipating......and in the time it took me to set the timing it dropped to pretty much zero. :shock:

I was surprised as idling for the amount of time it did with no oil pressure would have certainly caused nasty engine noises. It also surprised me as when I primed the oil system before putting the motor in the car, it was apparent from the load the drill was under that the pump was making some serious pressure. Additionally, looking under the oil cap showed what seemed to be adequate oil flow while running, so I began to suspect maybe the pressure was likely OK. Thinking further about the issue I realized this was the same oil pressure sending unit from the old motor......the one that was downstream of the oil pump that took a dump on me. I began to suspect possibly some schrapnel from the old oil pump wound up in the sending unit. I thought it was certainly worth a shot putting a new sending unit in before pulling this motor back out.

Luckily my hunch turned out to be correct and it wasn't something that I had overlooked while building this motor!

Image20180712_122652 by Shane Hewitt, on Flickr


Last edited by auto_god on Thu Jul 12, 2018 4:08 pm, edited 1 time in total.



Thu Jul 12, 2018 3:30 pm
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Joined: Wed Sep 03, 2014 8:59 pm
Posts: 220
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Post Re: Back in a Formula Again
Took the car out for a 20 km shake down run this afternoon to grab some data to start tuning the chip with all over again now. The new cam has totally changed the sound of the car (pretty much all the lope it had before is gone, replaced with a very deep sounding thump)......and honestly it does drive much nicer than the old one did. That is good as there were several things I wanted to address when selecting this cam.

Priority number 1 and really, the biggest reason I swapped motors is the last one failed the Idle Hydrocarbons portion of the emissions test. Passed everything else, but even with my idle speed up at 1200 rpm(1250 is the max allowed in the test), there was just too much seat to seat overlap with the old cam (58 degrees I believe, double what the stock cam had). The unfortunate thing with TPI injection being a batch fire system (all injectors fire all at once), is that due to the injectors firing twice per rpm, half of each cylinders fuel load is sitting right there at the intake valve when it opens, so during that overlap period a good portion of that goes right out the headers (causing high idle hydrocarbons). The other issue that creates is that catalytic convertors exposed to large amounts of hydrocarbons burn out quickly. I was pretty sure it was going to fail this part of the test as backing into my garage after being out for a cruise resulted in my wife commenting that "Your car stinks!" I'm pretty sure 2 years of being subjected to all the hydrocarbons that cam generated killed my Magnaflow convertor. Having said all that, I'm just starting tuning the new motor and haven't taken it to have the emission test redone yet, but the smell is gone, so I feel reasonably confident it should pass.

Issue number 2 I wanted to rectify was the idle speed. I really didn't have an issue with the idle speed (775 in gear, 875 in park/neutral), but it did cause the car to push against the brakes while stopping and sitting at lights. Not a huge issue, but if that could be resolved at the same time, that would be a bonus.


So after what seemed like weeks of simulations, I wound up with this.

http://www.lunatipower.com/Product.aspx?id=2010&gid=289

When you first look at the specs it seems like a pretty small cam, but when you look into Lunati's lobe database your perspective changes.

Comparing my old one to my new one.

Lunati BareBones 10030 Lunati Voodoo 60120
Duration .006" 278/288 263/271
Duration .050" 219/229 211/219
Duration .200 132/138 135/142
Lift .503/.503 .508/515


Overlap @ .006 58 deg 42 deg
Overlap @ .050 1 deg -9 deg

So with the new cam I've significantly reduced the valve overlap and toned the idle way down (sits and idles happily at 650 rpm in gear), yet when you look at the duration at .200" (where the cylinder heads are typically really starting to move some air), this new cam is actually bigger than the old one!!

Once I get through the break in period and finish up tuning it, I'm really curious to see what kind of snort this new motor has!


Thu Jul 12, 2018 4:07 pm
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