Which Small Block Olds is Better
February 5th, 2008, 04:52 PM
#1
78cutlass
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Which Small Block Olds is Better
If you wanted to build a "warmed over daily driver" small block Olds for a '78 Cutlass, which one of these two motors would be the better choice (explanations welcomed):
'69 Olds 350 with #5 heads
Olds 403 with #5 heads
'69 Olds 350 with #5 heads
Olds 403 with #5 heads
February 6th, 2008, 10:25 AM
#2
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If you are just building a daily driver you might be happier with the 403. It has a little bit more displacement and you will run the same heads on either engine so that won't be an issue. The big isssue with 403s is that they have windowed mains so it makes it more difficult to rev them higher. However, if you are just going to have a weekend warrior you probably won't red line the engine often. 
Then again, I have heard 403s have cooling issues since they have siamese cylinders. This can be overcome with a radiator and fan in good working condition though.
Then again, I have heard 403s have cooling issues since they have siamese cylinders. This can be overcome with a radiator and fan in good working condition though.
February 6th, 2008, 11:12 AM
#3
78cutlass
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Olds64,
Thanks for your input. If I went with the 403, I'd pick a torque cam in the 1400-4800 RPM range. I'd strive for a compression in the 9.5 to 1 or 10.1 range in order to keep things "pump-gas friendly". The #5's would allow me to achieve that compression easily. Thank you.
78cutlass
Thanks for your input. If I went with the 403, I'd pick a torque cam in the 1400-4800 RPM range. I'd strive for a compression in the 9.5 to 1 or 10.1 range in order to keep things "pump-gas friendly". The #5's would allow me to achieve that compression easily. Thank you.
78cutlass
February 6th, 2008, 04:47 PM
#4
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Well, don't base your decision solely on what I say. The 350 has merits too. Keep this post near the top and I am sure you will get alot more opinions. It is always good to get as much info as possible.
February 6th, 2008, 10:22 PM
#5
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For a "warmed over daily driver" windowed mains should not be an issue.
........ Then again, I have heard 403s have cooling issues ........
Norm
February 6th, 2008, 11:38 PM
#6
78cutlass
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88 Coupe,
I'd be content with 350 HP/350 FT LB TQ Olds small block motor as a daily driver. I think the '69 W-31 350, which was the "top dog" 350 motor, was a 325 HP/360 TQ motor. The regular '69 4-barrel 350 was about 310 HP/390 TQ! For a street driven car I'd be more interested in having a torquey motor than anything else, especially with the fact that a '78 Cutlass isn't a light car.
I'd be content with 350 HP/350 FT LB TQ Olds small block motor as a daily driver. I think the '69 W-31 350, which was the "top dog" 350 motor, was a 325 HP/360 TQ motor. The regular '69 4-barrel 350 was about 310 HP/390 TQ! For a street driven car I'd be more interested in having a torquey motor than anything else, especially with the fact that a '78 Cutlass isn't a light car.
Last edited by 78cutlass; February 6th, 2008 at 11:47 PM.
February 7th, 2008, 01:03 AM
#7
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78cutlass.
I do not know anything about all those numbers, and I certainly do not need BOLD fonts, to aid my reading comprehension.
I'm sure you will be happy with whatever you choose.
Thank you for telling me, but I already know how heavy it is.
Now, what was your point?
Norm
I do not know anything about all those numbers, and I certainly do not need BOLD fonts, to aid my reading comprehension.
I'm sure you will be happy with whatever you choose.
Thank you for telling me, but I already know how heavy it is.
Now, what was your point?
Norm
February 7th, 2008, 05:23 AM
#9
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However, if you are just going to have a weekend warrior you probably won't red line the engine often.
I have heard 403s have cooling issues
February 7th, 2008, 01:24 PM
#12
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Couple of things. First, those high torque 350s are high compression engines, in the 10.25 to 1 range, not really practical on today's pump gas. Second, as far as Oldsmobiles go, a 78 Cutlass is about the LIGHTEST car they made. I am no great 403 fan, but for a mild build it will work fine. Do your research on pistons and heads, you can easily end up with too much CR using the #5s. Personally, if I was going to do a 403, I would use the 4A head and the KBs, cr ends up around 9.6, perfect for pump gas. The 4As already have 1/2" bolt holes, correct dowel pin sizes, and big intake valves. A little work on the exhaust and you are good to go. If it is your first build, IMHO the 350 is easier and a little more forgiving.
February 7th, 2008, 07:58 PM
#16
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No.
I sent a simple reply, to a message with my name on it, followed by a question regarding its content. If it did not have my name on it, I would have ignored it.
What did you read into my post, that I did not write into it?
Norm
I sent a simple reply, to a message with my name on it, followed by a question regarding its content. If it did not have my name on it, I would have ignored it.
What did you read into my post, that I did not write into it?
Norm
February 7th, 2008, 08:39 PM
#17
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Kinda like when a "redneck" starts his story with "y'all ain't gonna believe this s**t".
Been there, done that.
You can go over to Real Oldspower.com and do some reading.
Key words being "seem to know".
Nuff said.
Norm
Been there, done that.
You can go over to Real Oldspower.com and do some reading.
Key words being "seem to know".
Originally Posted by tonycpe
the people at oldspower seem to have problems installing a rear view mirror.
Norm
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