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Old 09-07-2012, 02:34 PM
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grandville455 grandville455 is offline
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Well have u done a cranking comp test just to see what that is? Where did they set the cam at? CE rods are .041 stock so u have a even richer rod then that turned down? How fast is the secondary flaps opening etc. Sounds rich to me on WOT ,least for the carb.

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Old 09-07-2012, 02:56 PM
GTOLou GTOLou is offline
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Dumber things have happened (I've done them), but make sure your throttle is opening all the way. (when you press the pedal down all the way)

Doing a compression test is a great idea as well.

That sounds like a well thought out combo - should run pretty dang well...

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Old 09-07-2012, 03:17 PM
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462ta 462ta is offline
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ive asked the same question as my combo is almost identical to yours and on the dyno i have not come close to the 400-420 hp that they say is possible with this combo, my compression is the same as yours and that appears to be to low for this cam, now i have done some tuning, added set try y headers and 3 in exhaust and am going back to the dyno on the 15th weather permitting, 3.73 gearing to replace the 3.23 are an option i am considering, overall i am not overly impressed with my combination but it is getting better than it was at first, time wise my previous set up with smaller 2801 cam was same or slightly better.Getting closer to 10/1 comp may be a winter project for me.search 60916 cam for opinions given to me.

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Old 09-07-2012, 06:30 PM
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Quote:
Originally Posted by 462ta
ive asked the same question as my combo is almost identical to yours and on the dyno i have not come close to the 400-420 hp that they say is possible with this combo, my compression is the same as yours and that appears to be to low for this cam, now i have done some tuning, added set try y headers and 3 in exhaust and am going back to the dyno on the 15th weather permitting, 3.73 gearing to replace the 3.23 are an option i am considering, overall i am not overly impressed with my combination but it is getting better than it was at first, time wise my previous set up with smaller 2801 cam was same or slightly better.Getting closer to 10/1 comp may be a winter project for me.search 60916 cam for opinions given to me.
Well,if you're talking about chassis dynos and rear wheel hp figures,there's no way that sorta 400 cid combo will crank out 400 to 420 RWHP,as that's like 500+ hp at the flywheel.

Chassis dyno that sorta 400 cid combo should be somewhere between 300 to 340 RWHP max.

Now at the flywheel,yeah a 400 cid combo like that may be able to make right at 400 hp,but it's probably not gonna hit 420 hp,not without more cam,compression,head flow or something of that sort like Skip mentioned.

Quote:
Originally Posted by Ollie
The #16 heads are small valve that could be hurting HP as well.
That's not necessarily so,sorry.

There are three distinct #16 head castings,a small valve high compression version (1970 2bbl 400),a big valve high compression version ('68/'69 4bbl 400),and the round port SD455 heads.

So they easily could be big valve #16 heads.

Anyhow,I agree that a compression test is a good idea,never hurts to do that.

Also agree it sounds like it could use some further tuning.

Sometimes it takes some serious work (and a little luck) to get these things to run their best.

Good luck with it.

Bret P.

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