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Discussion Starter · #1 ·
I was kinda dissappointed, but I know theres more power to be had. My motor is set up more for the street than strip.

420hp 412 lb ft tq



<font size=-1>[ This Message was edited by: smokey212 on 6/9/06 8:54am ]</font>
 

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Discussion Starter · #3 ·
It's a 414. I think the carb is holding me back. It's a 750 stage 3 from bigs. I think that engine could use a 950 or so. I will be playing with it more after I take it down the track. If it hits the times I want I am not worried about getting more power. It's almost too much to put on the street now.
 

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It's tough to make out that a/f ratio line....it looks to be 13.0 or less at the top end though. Is that correct?

Looking at the wide flat torque line.....I'd agree. More carb.

You might consider checking out www.pro-system.com
 

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Discussion Starter · #5 ·
The A/F ratio is 13.1 after about 3800 rpm, all the way to redline. And that is right where you want it from what I understand. I do feel that a bigger carb would let it breath more.
 

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Why was the A/F so lean below 4200rpm? Seems like you'd get some more peak torque out of richening up the mix in the lower RPMs. I'd definitely say 420rwhp is nothing to be disappointed about, that's right around 500fwhp!
 

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Discussion Starter · #7 ·
They guy tuning is said the idle air bleeds were screwed almost all the way in. That is the way it came to me. I haven't touched the carb since I put it on the engine. But he did richn' it up at idle.
 

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Timing?
Trans?
Converter?
Gas type?
Heads?
Cam?

Need the full breakdown to help.

I would certainly call Jesse @ BIGS before hanging up the 750. I run a 950 (DaVinci) myself on a 418 and it's not too big. Patrick at Pro-Systems is probably one of the top 5 carb builders in the country so I would call him too.

But, let's see what else could be holding up the car first.
 

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Discussion Starter · #10 ·
Here are the specs

74 351w stroked to 414
AFR 205 heads
Cam motion .236.242 duration @.50
.618,.618 lift @.50
110LS
Hyd. roller lifters
Bigs 750 stage 3 with stealth dual plane intake
Thinking of going with the super vic jr.
10.8.1 CR
Manual trans through 9" detroit locker with 3:89 gears

I usally run 93oct gas with about 34 deg timing. The dyno showed the same numbers with timing at 32 deg, and the car didn't like to cut off at 34 deg so we left it at 32. I didn't dyno it with race fuel so I feel I could get a few more ponies from that. I think with a single plane intake and a 950 or so it would breath alot better.

<font size=-1>[ This Message was edited by: smokey212 on 6/12/06 10:05am ]</font>
 

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Intake is a problem too.

I'd go Vic Jr or the Super.

I still think the carb might hold you back too though. Try an intake change first I think.
 

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Ok. With that cam you're about on target. You need to add 25-30 more degrees @ 0.050" to get the power I think you desire.

Also, the hyd roller is sensitive to the spring pressures. I would have recommended a solid, 260-ish @ 0.050"

A vic Jr would be ideal. The super vic (which I run) is nice but with the 205's I would stick with the VJ.

You are probably on the detonation limit with that cam, compression and octane. Are you skilled at reading plugs? If so, did you check for evidence of detonation? If you want some assistance with plug reading, chime in.
 

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Discussion Starter · #13 ·
The plugs look great, and the dyno showed a ideal 13:1 A/F ratio above 4k or so. It was lean at idle, but it levels off when your full throttle. I'm going to get some passes at the track, then change out the intake first.
 

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Discussion Starter · #14 ·
Thanks for the tips JAM. I'll be playing with the combo more in a few weeks. I'm trying to get some seats and a cage in it so I can take it to the track. It has 3924's in it right now. That is a mostly stock plug. I had already thought about going to the 3922's already, and since you mentioned it I probably will go ahead and drop them. I'll let you know how that turns out. One question though. What gap do you guys normally run your plugs at with a msd ignition box and dizzy, with a blaster 3 coil?

<font size=-1>[ This Message was edited by: smokey212 on 6/18/06 10:59am ]</font>
 

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Cam is too small. Intake needs changed.

The intake is killing you two-fold. Dual plane intakes need more carb than a single plane.

The cam should provide good torque, and pull your nuts off from 2500 to 5500 rpm. More cam and a Victor Jr. or Super Victor (if you go with a BIG cam) will soften up the low end a little, but add more up top.

As for cam type. If you have the Crane link-bar lifters, you should be OK as long as you have PLENTY of spring pressure. You'll need more than what is usually called for. If you want to spin it a MAX of 6200-6500 rpm, the HR will be ok. If you want to get wild, solid lifters are in order.

Personally, I'd recommend around 10 more degrees @ 0.050" with a hydraulic roller, and either a port matched Victor Jr, or a Super Vic. The Super Vic's ports match the AFR 205 heads exactly, except the ports will be a little over 1/8" higher than those on the head. Milling the sides and bottom of the intake will move it down where it needs to be.

You'll need STRONG springs.

Good Luck!

_________________
66 mustang
302 4-speed 289 heads, 10.63 @ 129.3
http://www.mustangworks.com/cgi-bin/moi-display.cgi?220


<font size=-1>[ This Message was edited by: n2omike on 7/18/06 11:45am ]</font>
 
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