302s on a 360?

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Professor Fate

Professor Fate

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I've got a '90 360 roller motor, and guess what? The 308s are shot- big surprise. But I've got a good set of 302s that have been sitting on the shelf for too long... Now keep in mind this is a completely stock bottom-ended daily driver engine; the port size/flow is down on the 302s compared to the 308s, but I'd pick up a bit of compression (64cc vs.70cc approx.) on the pitiful 8:1 (advertised) 360- with a Mr. Gasket .028 head gasket I should be able to pick up a point or more.
So my question is: is it a viable combination? Is it a worthwhile tradeoff to lose a bit of flow and gain say, a point of compression in an otherwise stock, lower rpm workhorse? I just don't want to make it more anemic.
And before anybody mentions it, I would do a basic gasket match on the intakes to minimize the flow disruption...
 
I wouldn't just because of the 273/318 sized ports.
 
Just run them. I have them on a 360 that ran mid 12's with a dud cylinder and no fuel pressure.
 
In a truck with a small to mild camshaft, it will be a winner.
 
Stump puller. Just like the SP-2P intake, velocity and all in down low. Truck combo.
 
I had them on a stock 360, purple shaft 484 cam, mild port work, ld4b, 750 holley, 904, 3.55s. In a 71 scamp back in the mid 90s. Ran high 12s, used to smoke 5.0 stangs and surprised a lot of others with that car.
 
Professor Fate said:
I've got a '90 360 roller motor, and guess what? The 308s are shot- big surprise. But I've got a good set of 302s that have been sitting on the shelf for too long... Now keep in mind this is a completely stock bottom-ended daily driver engine; the port size/flow is down on the 302s compared to the 308s, but I'd pick up a bit of compression (64cc vs.70cc approx.) on the pitiful 8:1 (advertised) 360- with a Mr. Gasket .028 head gasket I should be able to pick up a point or more.
So my question is: is it a viable combination? Is it a worthwhile tradeoff to lose a bit of flow and gain say, a point of compression in an otherwise stock, lower rpm workhorse? I just don't want to make it more anemic.
And before anybody mentions it, I would do a basic gasket match on the intakes to minimize the flow disruption...
Click to expand...
Ultimately they will have a shorter power range and wont make the same power as the 308
 
A point of compression from 6cc?
I don't think so;
my math says maybe 4/10ths..
Your swept (at 4.00x3.58) is 737.4cc
To get 8.0 Scr requires 105.35cc
Subtracting 6cc is 99.35, and so
the new Scr is 8.42

In a throttled situation, this will make as good as zero difference.
It won't show up until WOT, and 'round about 4000rpm, or a lil sooner, those small ports are gonna put the brakes on.But with a stock cam,that's no big deal.
As others have said,you already have them, so just run them. I'd put an intake on them with matching ports tho.
Oh wait, I already did that,lol.
As others have said; it will be fine.
 
If you drive outside their ability, and its pretty easy... you'll find bad milage and even funnier will be when you have your foot into it... and as you let up, itll feel like its picking up speed in comparison.

The smaller chamber smaller ports there'll be lots of velocity and will do great under three grand/3000 rpm
 
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In an application like that, you could run them...... it should be fine.

Another option might be...... since it seems there are those looking for good clean 302’s, you might be able to sell them and take that money and put it towards refurbishing the 360 heads.
 
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