406 dyno results
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Pro
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From: Calgary
406 dyno results
I just posted this in engine mods. http://forums.corvetteforum.com/zerothread?id=258902
This engine should wake up the 74 :cheers:
I'll have to update my sig. now :cool:
[Modified by 74vetteman, 11:07 PM 3/16/2002]
This engine should wake up the 74 :cheers:
I'll have to update my sig. now :cool:
[Modified by 74vetteman, 11:07 PM 3/16/2002]
Instructor
Joined: Mar 2001
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Re: 406 dyno results (74vetteman)
74vetteman,
Those are some great #'s.
I have a fairly similar engine, with lesser heads (ported Sportsman II's) and a bigger cam (edelbrock RPM). My motor idles well and has tons of torque everywhere (I can take off from a stop in 4th gear!). I have not dynoe'd it yet, but it is making tons more HP and torque than my 327, which made 276 hp at the wheels with the same heads and a tiny exhaust system. I am hoping to get 350 hp at the rear wheels. I am going to dyno it as soon as I get it broken in. Hopefully I will post some #'s in a month or so.
I don't know why more people don't build 406's. I had a shortblock built by the best corvette shop around and it only cost me $1,500, which is less than I was quoted on a 383. The only downside I can see to the 406 is tire wear. At the rate I am going now, I am going to have to change my rear tires every time I change my oil.
Mike
Those are some great #'s.
I have a fairly similar engine, with lesser heads (ported Sportsman II's) and a bigger cam (edelbrock RPM). My motor idles well and has tons of torque everywhere (I can take off from a stop in 4th gear!). I have not dynoe'd it yet, but it is making tons more HP and torque than my 327, which made 276 hp at the wheels with the same heads and a tiny exhaust system. I am hoping to get 350 hp at the rear wheels. I am going to dyno it as soon as I get it broken in. Hopefully I will post some #'s in a month or so.
I don't know why more people don't build 406's. I had a shortblock built by the best corvette shop around and it only cost me $1,500, which is less than I was quoted on a 383. The only downside I can see to the 406 is tire wear. At the rate I am going now, I am going to have to change my rear tires every time I change my oil.
Mike
Advanced
Joined: Aug 2001
Posts: 51
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From: Mesa az
Re: 406 dyno results (damac)
"The only downside I can see to the 406 is tire wear. At the rate I am going now, I am going to have to change my rear tires every time I change my oil."
why not? the way i drive i have to change my rear tires everytime i get gas :jester
hey one question though? isn't the 383 suppose to be stronger then the 400 small block?? or are they both so strong it just dont matter?
why not? the way i drive i have to change my rear tires everytime i get gas :jester
hey one question though? isn't the 383 suppose to be stronger then the 400 small block?? or are they both so strong it just dont matter?
Racer
Joined: Nov 2000
Posts: 369
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From: Finland
Re: 406 dyno results (74vetteman)
Thanks for posting. Impressive numbers, especially those @3000rpm. Your results are very interesting to me as I'm planning a 406 buildup with almost the same setup. The difference in my plan is to use compcams 280 solid roller camshaft. Anyone willing to guess how much less streetable it would make the engine (otherwise similar to 74vettemans) at low rpms??
rgds Tomi
rgds Tomi
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Drifting
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Re: 406 dyno results (Tomi72)
I want to build a 406 with...Dart Pro 1 series heads. 11.5:1 JE. Eagle H beam 6" rods. Holley MPFI. Comp Cams XR-270. 1.6:1 roller rockers. Super-comp Headers. MSD 6AL-Blaster SS-pro-billet dist. Richmond 6 speed with a 3.73 rear. And maybe a 250 shot of N20 for a little more fun. :blueangel:
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From: Calgary
Re: 406 dyno results (taekwondo-kicker)
Taekwondoekicker,
IMO the 406 will always make significantly more power than a 383 if built exactly the same. They share the same stroke, but the 406 has bigger bores, so it will push down harder on the crank (more area). These larger bores also unshroud the valves better, contributing to better air flow. I dare say the cylinders are supported better (if you can find a block with thick bores) because they are siamesed. There is a reason the Bow Tie blocks also are siamesed.
While I was at the dyno shop there was a 383 there with the same heads, cam and valvetrain, but with the Holley commander fuel injection system, that made 45 lb/ft and 40 hp less than my 406 (his best numbers were ~450 lb/ft and 435 hp). I know it isn't apples to apples, and he didn't have the same block prep (fill etc.) but that is still a significant difference. However, both engines still make great power!
IMO the 406 will always make significantly more power than a 383 if built exactly the same. They share the same stroke, but the 406 has bigger bores, so it will push down harder on the crank (more area). These larger bores also unshroud the valves better, contributing to better air flow. I dare say the cylinders are supported better (if you can find a block with thick bores) because they are siamesed. There is a reason the Bow Tie blocks also are siamesed.
While I was at the dyno shop there was a 383 there with the same heads, cam and valvetrain, but with the Holley commander fuel injection system, that made 45 lb/ft and 40 hp less than my 406 (his best numbers were ~450 lb/ft and 435 hp). I know it isn't apples to apples, and he didn't have the same block prep (fill etc.) but that is still a significant difference. However, both engines still make great power!
Instructor
Joined: Mar 2001
Posts: 192
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Re: 406 dyno results (taekwondo-kicker)
Taekwondo-kicker,
A similary built 406 should always beat a 383. I did a lot of research and looked at a lot of dyno sheets for both motors and the 406's almost always make more power and torque. I went to one of he Camaro pages and saw a ton of guys in the 11's with 406's.
My engine builder quoted me $1,800 for a 383 shortblock and $1,550 for a 406 shortblock. 23 cubes for less$$ seemed like the way to go and I wasn't disappointed. I think people are under the impression that 383's are better because there are some many more of them out there. I was told that it would be hard to find a 400 block, but I called the local rebuilders supply shop and they had three of them and I paid $300 for a rebuildable shortblock. I think people go with the 383 just because it so easy to find a 350 block and buy a new Scat crank and stuff it in.
Mike
A similary built 406 should always beat a 383. I did a lot of research and looked at a lot of dyno sheets for both motors and the 406's almost always make more power and torque. I went to one of he Camaro pages and saw a ton of guys in the 11's with 406's.
My engine builder quoted me $1,800 for a 383 shortblock and $1,550 for a 406 shortblock. 23 cubes for less$$ seemed like the way to go and I wasn't disappointed. I think people are under the impression that 383's are better because there are some many more of them out there. I was told that it would be hard to find a 400 block, but I called the local rebuilders supply shop and they had three of them and I paid $300 for a rebuildable shortblock. I think people go with the 383 just because it so easy to find a 350 block and buy a new Scat crank and stuff it in.
Mike
Le Mans Master
Joined: Jul 2001
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From: absecon nj
Re: 406 dyno results (damac)
yeah i miss my 406 the torque was unreal off of the line..who knows with those numbers maybe its time to start building another one...very good numbers :cheers:
