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Time for a 406, What to do?

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Old 11-23-2001, 09:39 PM
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bulldogg
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Default Time for a 406, What to do?

Starting components:
Superram, upper and lower.
AFR 190's, 76cc., w/2.02--1.60's.
Art Carr Transmission
Speedpro engine management system.
Going to go with 4340 rods and crank, and J & E pistons.
AFR's will be ported and polished before going back in.
Probably go with World or Dart cylinder block.
Goals:
525-575 hp. w/o nitrous.
cruisable, streetable.
Questions:
Is there a website that has numbers on the superram capabilities. Was wanting to know what it flows after 6500rpm.
What is the most compression I can put to it and still run 94 pump gas.
How can I compute what octane levels are needed for compression ratios.
Still undecided on whether to get domed pistons or to shave on heads to bump compression, could use your opinions there as well as what cam would work well.
Will come back with more ??'s for u guys as things progress.
Thanx


Old 11-24-2001, 01:28 AM
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HWoods
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Default Re: Time for a 406, What to do? (bulldogg)

If you are looking for torque, the super ram is what you want, if you want high rpm, go with a modified mini ram or a sheet metal intake or one of the other carb type fuel injected intake system. Lingenfelter offers one.
Old 11-24-2001, 04:15 AM
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ol,RJ
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Default Re: Time for a 406, What to do? (bulldogg)

you may be able to get to your goals without going over 6500rpm.
but if you really want to spin it that high, even the mini ram has trouble above 6500rpm. a single plane intake converted to fuel injection would be needed to make good power in the 7000rpm range. but from what I have read it can be difficult to tune in a high rev'ing(7000+rpm) package, the injector size must be very big to flow enough in such a short time.

compression can depend greatly on what cam you use, more duration lets you get away with higher compression.
(I have 11 to 1 comp with a 246dur @ .050" solid roller cam on my 406, while its not tuned in yet, it does look to be fine so far on 93octane).

I'd look at keeping the S/R , porting it and your heads, maybe a cam in the 232dur@ .050 range (hyd, less maint).
Then let the 500+ ft lb of torque do the work. just a opinion.
Old 11-24-2001, 05:49 AM
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AquaMetallic94LT1
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Default Re: Time for a 406, What to do? (bulldogg)

Starting components:

Superram, upper and lower - Good.
AFR 190's, 76cc., w/2.02--1.60's - Good.
Art Carr Transmission - Good w/ Dana 44
Speedpro engine management system - Good, look into putting a GM Speed density ECM. The factory ecm does a lot of stuff for you.
Going to go with 4340 rods and crank, and J & E pistons. - Good
AFR's will be ported and polished before going back in. - Good
Probably go with World or Dart cylinder block. - Good

Goals:
525-575 hp. w/o nitrous.
This is going to be tough with a superram. Lingenfelter has a 420 ci engine that made 525 HP with ported AFR 190 heads and a ported supperam. The cam was a mechanical roller 236/244 duration @ .050 , 110 LSA, .549/.549 @ 1.5 rocker ratio lift. I calculated that you will need to make peak power around 5700 to get to 525hp based his motor. You may need a bit more cam.

cruisable, streetable.
Should be. FI tones down cams pretty well. The 110 LSA will definitely give you a loping idle.

Questions:
Is there a website that has numbers on the superram capabilities. Was wanting to know what it flows after 6500rpm.
Not that I know of but based on dyno stuff from his book, the superram starts to fall off around 5500 and is done by 6000. This isn't all bad because your really don't need to go over 6000 to make good hp. The low and midrange torque of the superram is worth giving up the peak hp that you would get from a miniram.

What is the most compression I can put to it and still run 94 pump gas.
You should be able to safely run 10.5 to 11:1 if you use a knock sensor.

How can I compute what octane levels are needed for compression ratios.
There's no way to calculate this. Its really a function of cam size, cooling system, chamber design, and cylinder bore size.

Still undecided on whether to get domed pistons or to shave on heads to bump compression, could use your opinions there as well as what cam would work well.
Flat top pistons. They make the most power.

I did some runs on desktop dyno. Using the same cam that lingenfelter used run with a 110 intake centerline (straight up in cam lingo) and a superram intake, the numbers are 509 hp @ 5500 rpm & 537 ft lbs @ 4000 rpm. Going to a single plane intake will give you 533 hp @ 6000 & 533 ft lbs @ 4500. I used the flow numbers from the AFR website for the comp ported 190 heads.

Old 11-24-2001, 04:12 PM
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bulldogg
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Default Re: Time for a 406, What to do? (AquaMetallic94LT1)

The Speedpro is a DFI unit, that has the wideband O2 sensor, I really like it.

I was wanting to know the formula for octane to compression ratio, so that when I do complete my setup, (cam specs, pistons, etc..), and have my compression ratio, I want to be able to figure out what Octane level I will need to keep it from spark knocking.
If I set it up and find out I need minimum 96 octane, then I'll know I have to run a gallon or two of C16 with my pump gas.
So, is there a formula to figure this out. Say, I come out with a 12.5 compression ratio, then what Octane level would I need to keep from spark knocking? Or am I oversimplifying it?
What is a Desktop Dyno? Is it a website or a program? Sounds like I might need one.
Thanks
Old 11-24-2001, 05:17 PM
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Default Re: Time for a 406, What to do? (bulldogg)

desktop dyno 2000.
jegs part #720-3626 $39.99 order# 1-800-345-4545
Great program. Plug in engine size, compression, cam, intake, head flow#'s, boost, nos, etc and it gives you hp and torgue dyno charts and graphs.
Old 11-24-2001, 05:23 PM
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Default Re: Time for a 406, What to do? (blackguard)

while on the subject, can someone give me an idea of what cams I should look at.My combo will be:
4-bolt 400 block, not sure if going 377 or 406 but a forged crank and rods is a definite.
miniram II intake
58mm ASM throttlebody
Brodix Track1 heads, fully ported.
and probably a 150 shot of NOS, direct port.
I want to be at about 500 N/A and 650 on NOS. Thanks.
Old 11-25-2001, 02:48 AM
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Default Re: Time for a 406, What to do? (bulldogg)

bulldogg -

12.5:1 is pretty high. You should be able to run 11:1 with 92 octane. I have feeling your going to need 100 octane for 12.5:1 but its just a wild guess.

blackdog -

Ported track 1 heads are going to be pretty big heads. A 406 is probably a good idea for heads that big and 500 hp should easy to get. You may be able to get 520 hp. A 236/244 112 LSA duration camshaft should get you to the hp level your looking for.

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