#65683 - 07/24/11 04:16 PM
Re: Nova project progress
[Re: strokersix]
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strokersix
Active BB Member
Registered: 05/23/09
Posts: 303
Loc: NW Illinois, USA
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I noticed one pushrod wasn't spinning based on witness marks from the guide. That raises the question of whether a lifter also isn't spinning so I checked all the lobe lifts. All were .266-.268 versus .2706 on the cam card. I think and hope all is OK with the cam. This is the fourth engine I've had this cam in and at least the second set of lifters so it doesn't owe me anything.
And the throttle bracket:
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#65813 - 08/01/11 08:39 PM
Re: Nova project progress
[Re: strokersix]
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Mean buzzen half dozen A.K.A. Hank
Active BB Member
Registered: 09/23/04
Posts: 4544
Loc: Ca
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What do you think about a rev limiter? Then I could keep my right foot planted while I run thru the gears.
I would,, Maybe a MSD 6AL box?
They seem to hit soft & not make any sharp or abrupt change when it hits the rev limiter.
I ran one in my Camaro when it was Paxton supercharged, very mild hitting.
I remember when I put in a 6000 RPM limit chip in the box, my Autometer tach needle would read about 5500 RPM & the engine was missing, I did not think it was actually hitting the rev limiter, engine reved quicker than the needle could move.
My friend told me to put the 7000 RPM chip in the MSD box & bam, that was it no miss,, damm engine reved too quick LOL.
BTW, what M20 do you have, close or wide ratio?
As far as running good ET's, IIRC, my best ET @ a 3000+ elevation track was when I ran a wide ratio M21 4 spd a very, very mild 250 .030 over, approx 10:1 compression,4 bbl intake & a small 500 CFM AFB. 4:10 gears
I ran a 14.3 which I thought was slow @ the time, I was always comparring to the V-8's, come to find out here, it would have been a record that would still be standing here today in the International inliners record books, I still thinks that funny. 
I have run many different combos, memory fads a bit but I found the timeslip w/what combo & had @ the time I ran.
I had the original 3spd, horrible 2nd to 3rd gear RPM drop,4spd Muncie,5 spd T50 & a TH350, next a 4L85E
MBHD
_________________________
12 port SDS EFI 
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#65965 - 08/15/11 07:21 PM
Re: Nova project progress
[Re: strokersix]
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strokersix
Active BB Member
Registered: 05/23/09
Posts: 303
Loc: NW Illinois, USA
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Limited mechanical advance by adding weld to the weight tips.
The added 1/2 inch riser under the carb required air cleaner modification for hood clearance and now has a big block engine decal. Also note the header tubes and welds are turning color already. Hooked up my old Edelbrock O2 sensor (not wideband) and indicates the carb might be a bit rich but not excessive.
Now the bad news. Something broke in the valvetrain. Not sure what. It sounds like a 250 in an old pickup truck, no offense to truck owners here, just a reference to the typical well used 250 ticking valvetrain. My first guess is a cam lobe went flat but we'll see. Maybe I should drive a little slower.... NOT!
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#65978 - 08/17/11 07:20 PM
Re: Nova project progress
[Re: strokersix]
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strokersix
Active BB Member
Registered: 05/23/09
Posts: 303
Loc: NW Illinois, USA
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Good news! Pulled the valve cover tonite and it was immediately obvious that #5 intake rocker was loose. Pulled all 12 rockers off. I checked all the cam lobe lifts (Comp 252) and all good. All 12 pushrods are now spinning. Torqued the head bolts to 95 lb-ft, some were at about 85, some didn't move. Then reset all 12 rockers to 1/2 turn preload and cinched the locking setscrews tighter this time. Manifold fasteners all tight. The loose rocker doesn't roll as silky-smooth as the other 11 but I think it's OK.
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#65979 - 08/17/11 07:25 PM
Re: Nova project progress
[Re: strokersix]
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tlowe #1716
12 PORT ADVERTISER
Active BB Member
Registered: 04/01/04
Posts: 2324
Loc: Dysart, Iowa
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That is good news! Had me worried. Glad it was something simple. Did you take it back out for a spin?
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#66010 - 08/19/11 08:22 PM
Re: Nova project progress
[Re: strokersix]
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tlowe #1716
12 PORT ADVERTISER
Active BB Member
Registered: 04/01/04
Posts: 2324
Loc: Dysart, Iowa
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The dyno motors were tested at higher total timing (34-36). We were running much higher octane though (110 sunaco).
32 degrees ain't bad and much safer with low octane fuel. The bathtub chambers do like plenty of timing.
8-10 initial will help back the total down also.
You need to get that WBO2 hooked up. Do not expect the engine to like running at stoich (14.7 to 1). Mine likes 12.75-13 at idle. The guage will be more of a reference. It is effected by plenty of variables. Cam, timing and exhaust leaks will make it read funny. I was told long ago to use it as a reference to find where the engine likes to run at. This A/F varies at different rpms and loads.
Does the engine run any differnt with the last head/ valve setup?
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#66018 - 08/20/11 06:02 AM
Re: Nova project progress
[Re: strokersix]
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tlowe #1716
12 PORT ADVERTISER
Active BB Member
Registered: 04/01/04
Posts: 2324
Loc: Dysart, Iowa
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Try to get some more vids.
How about that shifter? It will take longer to install that. But it will put a big grin on your face.
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#66020 - 08/20/11 06:33 AM
Re: Nova project progress
[Re: tlowe #1716]
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strokersix
Active BB Member
Registered: 05/23/09
Posts: 303
Loc: NW Illinois, USA
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I'll have to pull the seats, console, and carpet, then do some floor modification to get the shifter installed. Need to work up motivation for that. Seats out will be a good time to install the WB gage.
Nobody here has run the HEI module rev limiter??????
http://www.northernautoparts.com/ProductModelDetail.cfm?ProductModelId=15650
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#66030 - 08/20/11 04:52 PM
Re: Nova project progress
[Re: strokersix]
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Mean buzzen half dozen A.K.A. Hank
Active BB Member
Registered: 09/23/04
Posts: 4544
Loc: Ca
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I am not saying you cannot tune w/a narrow band, it's possible & has been done for many many years.
It's just the narrow band is so slow in response time your A/F ratios could be way off @ especially during gear shift points.
I did tune my Syclone w/a narrow band O2 & w/that (narrow O2 sensor) I had the worlds fastest stock turboed Syclone, for about 8 years. I had no extra cash to get a wideband.
I did have a reading problem during the shift points though, the narrow band would show full rich @ the top of each gear change (thinking it was fine) but actually was dangerously lean,there was a couple second delay with the readings w/the narrow band O2.
I now use an old Innovate LM1 unit on the Syclone.
It was not until I wanted to turn up the boost & lean on it a bit more, (lean it out)I would only feel comfortable doing this with a wideband. I could have done it w/a narrow band,just much safer w/a wideband IMO.
Guys still tune there Buick GNs & Regal T-Types w/there stock narrow band, getting advise that has been passed down from older owners, there were so many of those cars made it's pretty easy to get good info on what works & what does not work & what's lean & what is rich, all measured in millivolts w/there scan tools.
One of the main reasons I tell guys to get a wide band O2 is to speed up the tuning process, most times you do not need to take out your plugs to look @ them.
It would be absolutely essential to get a wideband when you are forced induction, being too lean will destroy an engine very quickly & a wideband takes away the guessing, you know exactly when it's too lean or too rich right there & right now. 
When I had the Paxton superchager on my inline 6 I did it the old fashion way, I jetted it richer right off the bat as compared to my normally aspirated set-up. Took plug readings (a lot) It was a somewhat long process tuning 3 DCOE's, but hey I learned.
MBHD
_________________________
12 port SDS EFI
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