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Gear Heads Forever : ) Love it!

CNC

Supporting Member
Joined
Sep 2, 2013
Messages
563
Location
Monument Colorado
My XLR/V(s)
2006 Gold Mist XLR & 79' Eldorado Convert
Another project going on. A month ago I came across a 1978 Olds Tornado on Craig's List in Scottsbluff Nebraska. The car is a basket case but had the original 'all there' 403ci V8 4bbl Rochester with TH 40025 Trans and 3:07 Diff. Hadn't run for a few years. But hooked up a remote gas can, extra battery on hand, primed the carb, and she fired right up. Ran good on 7 cylinders out of 8. Number 6 read '0' compression. All others at 140 lbs. 95,000 miles on odometer. My guess? A valve is stuck open, or broken valve spring. Haven't pulled heads yet. :) The car is a rust bucket mess. It is roached, and disgusting to work on. So presently it is up on jack stands in my garage. I am keeping the engine, trans and final drive. The rest of the car, after stripping salvageable parts is going to the crusher. Yes, I know about the weak windowed main bearings on these, but it the same engine used in Trans Ams, 6.6L. For $500 bucks, couldn't pass. Presently waiting on arrival of 2 1/16" hub nut socket to pull CV Axles. Just when I thought I owned every sized socket made. Yeah right. :rolleyes: Neighbors nearby think I am 'nuts', (as does my wife). Yes, evidence of mice evident having called it home. When I pulled the flywheel shield and the starter motor after engine run, found that they had been living in the bell housing. They did not coexist well with the flywheel once engine started even though long previously deceased. As in. Ewww. Yuk!
 

nbw123

Seasoned Member
Joined
Mar 11, 2017
Messages
55
Location
Holland, MI
You my friend are a gear head. But there aren't more than 10 gear heads residing here. Most don't know which end of the wrench to hold. [emoji6]


Sent from my iPhone using Tapatalk
 

CNC

Supporting Member
Joined
Sep 2, 2013
Messages
563
Location
Monument Colorado
My XLR/V(s)
2006 Gold Mist XLR & 79' Eldorado Convert
It's a sickness, really. : )

You my friend are a gear head. But there aren't more than 10 gear heads residing here. Most don't know which end of the wrench to hold. [emoji6]


Sent from my iPhone using Tapatalk

The effort with The Toronado engine removal does have a purpose. :cool: The 403 while having it's issues (windowed main bearings) is a really good engine with a massive bore and relatively short stroke. It responds well to a cam change and increased compression. I do not plan to overbore it because of the siamesed cylinders. Bore stock is 4.35. Huge. Larger than a big block chevy. I will go through the whole engine, Have the rod and main journals over ground, then chrome plated and taken to within .002 of bearing clearance. Wish I could find 'production' forged aluminum pistons for it, but apparently no one is making them in standard bore? Don't want to pay for custom fabrication. So will run cast pistons. Like the 400 sb chev, they are prone to over heating due to the siamesed cylinders with steam passages. I will install a pair of 307 5A Heads on it with 2.0 (approx.) and 1.62 exhausts. Polish and port them + flow bench. They must be drilled for the steam holes. The combustion chambers are .68cc. So with .020 shaved off the heads, they should make around 10.1:1 compression. Will require High Test Gas. The heads are a direct interchange. Came off an 84' Delta 88. Will run a mild Lunati roller cam and lifters and roller rockers. Will blue print and balance the whole rotating assembly. At this altitude we cannot run high overlap cams. Thin air. I figure when all is done, it will make around 400 hp. So far, on paper. But will put it on an engine dyno once completed. Red line at around 5,800 RPM.

The ultimate purpose? It's a direct bolt in into my 1979 Eldorado Convertible presently with the 170hp olds 350V8. Will also rebuild and use the TH425 Trans (super tough trans) out of the Toronado as well as the Toronado Ring & Pinion 3:07 ratio. Presently the Eldorado has 2:72 ratio. Plan to also install an electronic switch pitch torque converter. Believe that this will "Wake The Eldorado Up". Don't really want a 'hot rod', just lots better performance. Right now, it is a 'dog' in the power dept. :( So, "solve the problem".

Thanks for commenting. ;)
 

nbw123

Seasoned Member
Joined
Mar 11, 2017
Messages
55
Location
Holland, MI
The effort with The Toronado engine removal does have a purpose. :cool: The 403 while having it's issues (windowed main bearings) is a really good engine with a massive bore and relatively short stroke. It responds well to a cam change and increased compression. I do not plan to overbore it because of the siamesed cylinders. Bore stock is 4.35. Huge. Larger than a big block chevy. I will go through the whole engine, Have the rod and main journals over ground, then chrome plated and taken to within .002 of bearing clearance. Wish I could find 'production' forged aluminum pistons for it, but apparently no one is making them in standard bore? Don't want to pay for custom fabrication. So will run cast pistons. Like the 400 sb chev, they are prone to over heating due to the siamesed cylinders with steam passages. I will install a pair of 307 5A Heads on it with 2.0 (approx.) and 1.62 exhausts. Polish and port them + flow bench. They must be drilled for the steam holes. The combustion chambers are .68cc. So with .020 shaved off the heads, they should make around 10.1:1 compression. Will require High Test Gas. The heads are a direct interchange. Came off an 84' Delta 88. Will run a mild Lunati roller cam and lifters and roller rockers. Will blue print and balance the whole rotating assembly. At this altitude we cannot run high overlap cams. Thin air. I figure when all is done, it will make around 400 hp. So far, on paper. But will put it on an engine dyno once completed. Red line at around 5,800 RPM.

The ultimate purpose? It's a direct bolt in into my 1979 Eldorado Convertible presently with the 170hp olds 350V8. Will also rebuild and use the TH425 Trans (super tough trans) out of the Toronado as well as the Toronado Ring & Pinion 3:07 ratio. Presently the Eldorado has 2:72 ratio. Plan to also install an electronic switch pitch torque converter. Believe that this will "Wake The Eldorado Up". Don't really want a 'hot rod', just lots better performance. Right now, it is a 'dog' in the power dept. :( So, "solve the problem".

Thanks for commenting. ;)

My fun car is a 2011 CTS-V 726whp before NOS. Ultimate goal is 1000whp daily driver. I upgraded to trick flow heads, ported and polished, and forged internals. Increased CR from 9.3 up to 10.1. More pulley, better cooling for intercooler, NW102 TB.... Its a beast.
 

CNC

Supporting Member
Joined
Sep 2, 2013
Messages
563
Location
Monument Colorado
My XLR/V(s)
2006 Gold Mist XLR & 79' Eldorado Convert
Holy Crap.

My fun car is a 2011 CTS-V 726whp before NOS. Ultimate goal is 1000whp daily driver. I upgraded to trick flow heads, ported and polished, and forged internals. Increased CR from 9.3 up to 10.1. More pulley, better cooling for intercooler, NW102 TB.... Its a beast.

It has to be a 'rocket' with 726whp. The 726 wheel horse power isn't a stock spec, is it? I know The CTS-V stock is 'pin you to your seat fast', right out of the box. I drove one sometime back and was 'Whoa!' when I tromped on it. What did you do to it to make 726whp? Were the heads the key and the increased boost? How do you plan to bump it to 1000whp? Do you still plan to keep the nitrous (NOS) at 10,1:1 compression? Aren't you concerned about detonation if it leans out on you? I have seen engines explode on Nitrous at high RPM when they leaned out. Ugly. On one occasion a buddy's car sent pieces of the engine ripping through the hood when it exploded. He didn't get hurt, but you could put the engine in a basket afterward. Here, the thin air really is a problem trying to make H.P. Causes a natural 'thin air lean burn' situation. Huge negative for NOS. The guys racing Pikes Peak are running 14.1:1 compression and low profile RV cams. They can successfully do so on 87 octane gas. Crazy huh? So since it's less air?, squeeze it harder. Yet we still have a -25% reduction in Sea Level rated H.P. Ex.,The Eldorado at rated Sea Level 170bhp, here is 128bhp. And a heavy car. Ugh. It is a 'dog'.
 

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