Will this work on the street?

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1973Barracuda

1973Barracuda

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I have found a rebuilt 360 for sale(great deal), 030 over, about 11:1, roller rockers, and a Engle cam 557/575. My question is with the compression, should I worry about pump gas? I think the cam will be too much, I would go with something around the 268 or 272 Comp. If the compression is too high and I go with say thicker gaskets, now I am messing with the quench.This will be a real driver, I am concerned this may be more work than it is worth for the street. I am reasonably competent mechanically, but would love some advice.
Jason
 
I'm running a 578 lift roller cam on the street, the lift isn't the problem though, it's the duration that makes the difference between being a good street-able cam or not. What is the duration?

11-1 is not that bad either, I wouldn't go any higher though. A stock 68-70 340 has 10.5

My final compression is around 12.4-1 after the blower boost. I run 93 octane pump gas and have no issues for street use.
 
Yeah!!...I'd do it!!....but I tend to like to do things that everyone likes to say can't be or shouldn't be done, just to see if I can make it work....sort of a challenge. Plus, if this engine's a "deal".....go for it!
 
I'd be worried about the compression ratio. A thicker head gasket can help but I don't think it'll be enough. Then again, if the price was right, I think a set of Keith Black pistons would be a fairly cheap fix for it. Cam is probably a bit much for the street too, but if it has a long enough duration that helps bleed off some of the cylinder pressure. If you're going to change the cam anyway, do the pistons too.

This is assuming the high compression ratio is due top the pistons in the engine. If somebody milled the heads a bunch to raise the CR then that's a bit of a different story.
 
Don't remember the duration. The only thing I am trying to avoid is buying a rebuilt motor, then rebuilding it all. I don't ming putting a new cam in there, I just know how some projects go, before I know it, I have to change everything. I am debating whether to go the 360 route, or upgrade my 318. Part of the appeal is this motor is complete. And I kinda hate to dump money in the 318 and still want more. All advice is appreciated.
Thanks
 
I ran my 11.9 to 1 416 on the street using 93 pump gas,no problems..and my current 360 has 10.7 to 1 comp.running the same fuel:-D:-D
 
Blownfish said:
I'm running a 578 lift roller cam on the street, the lift isn't the problem though, it's the duration that makes the difference between being a good street-able cam or not. What is the duration?

11-1 is not that bad either, I wouldn't go any higher though. A stock 68-70 340 has 10.5

My final compression is around 12.4-1 after the blower boost. I run 93 octane pump gas and have no issues for street use.
Click to expand...
i have always wondered what your compression is before the boost??
 
1973Barracuda said:
I have found a rebuilt 360 for sale(great deal), 030 over, about 11:1, roller rockers, and a Engle cam 557/575. My question is with the compression, should I worry about pump gas? I think the cam will be too much, I would go with something around the 268 or 272 Comp. If the compression is too high and I go with say thicker gaskets, now I am messing with the quench.This will be a real driver, I am concerned this may be more work than it is worth for the street. I am reasonably competent mechanically, but would love some advice.
Jason
Click to expand...

Here's my similar combo and it does just fine on the street with 93 octane and some octane boost. 1978 360,.030 over. cast crank, Mopar Performance forged pistons 11.0-1 compression with M/P rods and ARP bolts. Comp cam 260/260 duration @ .050 .555/.555 lift-solid cam, comp timing set.
Fully ported J-style heads with 2.055/1.60 11/32 SS valves, flows 261/175 CFM, chrome moly retainers, correct springs.
Harland Sharp alum 1.5 roller rockers.
Holley strip dominator intake.
Modified Holley 800 CFM carb.
balanced and blueprinted, 441 H/P @6200 rpm on the dyno before final tweaking to carb.

Here we are on the street scaring my Wife in second gear. LOL.

 
1973Barracuda said:
I have found a rebuilt 360 for sale(great deal), 030 over, about 11:1, roller rockers, and a Engle cam 557/575. My question is with the compression, should I worry about pump gas? I think the cam will be too much, I would go with something around the 268 or 272 Comp. If the compression is too high and I go with say thicker gaskets, now I am messing with the quench.This will be a real driver, I am concerned this may be more work than it is worth for the street. I am reasonably competent mechanically, but would love some advice.
Jason
Click to expand...

What heads are on the 360?What is the duration@ .050 on the intake and exhaust what is the CL?Where do you live maybe E85 is an option?
 
The issue with compression and the heads metal along with a cam is balance.
Your not going to get away with a advertised duration of what you listed with that ratio.

Iron or aluminum heads?

Heres another cave eat with to much compresion and pump gas.

IF the ratio is high and the cam isn't big enuff to bleed off compresion, then, you'lll need to retarrd the timing so it is driveable and you'll just simply loose more power than if you had done it right in the first place.

Stroked runs a 11.9-1 on his 416? Great. How big is the cam?

Blownfish;
I'm running a 578 lift roller cam on the street,
Click to expand...
At 578 lift, this cam isn't small.

And Spaz' combo;
1978 360,.030 over. cast crank, Mopar Performance forged pistons 11.0-1 compression with M/P rods and ARP bolts. Comp cam 260/260 duration @ .050 .555/.555 lift-solid cam, comp timing set.
Click to expand...

(Humm, tastey dishes!)

Can ya live with this and a high stall verter and gears? It sure makes for a ton-o-fun.
 
The advice from all of you has me thinking. I may have to alter the 360 if I buy it. I need something I can live with. Probably need to sleep on it before dropping the cake on it. I also contacted a member of FABO about some magnum heads, but I am not sure if the 318 has the potential to make me happy in the end.
Jason
 
The heads are iron, mild port so he says. I am beginning to think this may be more trouble than worth for my daily driver.
 
what are the cam specs?

IMG_0446.JPG
 
I will contact the owner again tomorrow for the cam specs. I am an E body owner, but the activity on FABO is way higher than FEBO! I am a previous A body guy(73 Duster, 68 Barracuda Fastback Formula S 383-wish I still had that one!). Many thanks to all.
 
stroked 340 said:
.533/.552............
Click to expand...

Thanks

1973Barracuda said:
I will contact the owner again tomorrow for the cam specs. I am an E body owner, but the activity on FABO is way higher than FEBO! I am a previous A body guy(73 Duster, 68 Barracuda Fastback Formula S 383-wish I still had that one!). Many thanks to all.
Click to expand...

Auto or 4spd. My 73 is a 4spd, now with a 360 and 4.10's.
 
My 73 is an auto 727, 2.76
The rear has to go, it's killing my performance, well, it is a factor. The stockish 318 ain't helping either.
 
There must be a million MoPar fans from Clarksville Tn. I think they'll be no problem getting a 360 for your car or help with it.
 
All you can do is bolt that sucker into the car and see how it does on the street.

More fun with a four speed by the way!

I'm running 3.23 gears and get great gas mileage on the highway and good RPMs at 65 mph.
 
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