Why does my car feel sluggish?

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magnumdust

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I just got my car finished yesterday and i've been driving it around and the car doesnt feel remotely fast enough for what i was expecting.

Setup:
Junkyard 360 magnum(turned out to be a freshly rebuilt engine)
Hughes Iron ram heads(stock 1.9x valve)
Custom ground cam from IMM
crosswind air-gap intake
3000 stall convertor
Hedman headers
3.55 gears
edelbrock 600cfm carb
Timing set at 16 out.

Specs on the cam(though i know zero about them):
Gross valve lift: intake/exhaust: .513
duration @ .006: 276/282
duration@ .050 : 224/230
Lobe lift: .3210/.3210
Lobe duration: 110

The car feels sluggish. I'd ballpark it at running a high 14/low15 second pass.

I'm wondering if its not enough carb or simply a matter of the "stock" transmission(minus the convertor)
 
what size converter ie 10" 11" ? was the crosswind port matched to the heads ? carb might not be big enough , what is it in ?
 
cannucky said:
what size converter ie 10" 11" ? was the crosswind port matched to the heads ? carb might not be big enough , what is it in ?
Click to expand...

I'm not positive(bought it from a member here), but i believe it was a 10" convertor. The crosswind is not port matched.

Its in a 73' duster.
 
Total timing? Is the carb opening all the way? Rear gears? Does it sputter/stall/fall on its face or anything funny?
 
Baxter61 said:
Total timing? Is the carb opening all the way? Rear gears? Does it sputter/stall/fall on its face or anything funny?
Click to expand...

Not sure on the total timing, he originally set it at 8 per what was suggested for the magnum engine, then when he re-timed it this morning at 16 advance.

Carb is opening all the way, 3.55 gears, and it doesnt sputter/fall on its face at all. Just doesnt feel potent.
 
I would seriously look at the carb size, I run a warmed 318 and have an 850 Thermoquad on top.
 
get a compression check on all the cylinders if you can... or at least, take each plug out and inspect it. make sure you got all 8 running at full potential. look for any of the plugs that looks different. you could have a bad lifter, bad plug wire, maybe heads need to be retorqued, could be a lot of things. something is holding her back, it's hard to say. get a look at the plugs if you are able. they should all be a nice tan look, like the ladies on the beach :D if any are wet / oily / fouled looking that might help you track this down
 
abodyjoe said:
carb sounds small.


what is the total timing?
Click to expand...

I'm not sure on the total timing.

Anyways, i guess next week(after i have some miles on the car) i'll check the plugs and the compression. Then order a bigger carb with my next check.
 
go over everything else before you spend any money. you really need to find out what your total timing is.
 
Get rid of the taxi cab carb.

Time it at 16 initial and about 32-33 total all in at 3k or a little less.

Should idle easily at about 800-850, even less.
 
What's the compression, that cam is going to want at least 10 to 10 1/2 to 1.
Could use some more carb also.
 
You could try another carb. The engine will handle it. But I have to go with you need a different gear. That would be a great gear for a 440. First thing I thought when I read your post. You still should check timing, compression, all the other things mentioned. How is the acceleration from 90 on up?LOL
 
The carb is a little small ,but dont go crazy with a huge carb (thats even worse IMO).Im running low 11's with a mlid 408 and a 750 carb. I would go with a 650 DP in your case.I think the gears are too high with that cam and thats killing it .I would go for 3.91 or 4.10 .As said before check out your timing and verify your compression in each cylinder first ,before you change too much so your not chasing your tail ...
 
magnumdust said:
I'm not sure on the total timing.

Anyways, i guess next week(after i have some miles on the car) i'll check the plugs and the compression. Then order a bigger carb with my next check.
Click to expand...

Instead of ordering a carb, double check everything else first. Then see if someone has a carb you can try, and see if that makes a difference.

Then you can make a better decision as to what to do. For the engine you have a 600cfm does seem small.
 
Something guys left out, what is the engine operating temp?

How about the REST of the exhaust system? Any chance the mufflers are "under" capacity?

And you have GOT to figure out what the total timing is, and check your dist. advance cure, and right NOW is a great time to do it

Check the balancer timing marks with a piston stop. Degree the balancer if it is not, or get the proper timing tape.

What do the plugs look like? Any chance the carb is too lean?
 
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