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406 HP Estimation?

 
TyEdUp
I love my Chevy Chevette!
Posts: 4
Joined: 07/12
Posted: 07/11/12 12:28 AM

So, I've been looking at buying a very nice 90 R/S that has a 406 with flat top pistons, 750 edelbrock carb, 280 cam, roller rockers, and a 400 auto tranny with a hurst shift kit (3spd), and posi-trac rear end. It was built about a year ago by a friend's father, and there's nowhere around here to have it dyno'd. Was wondering if anyone could give me a guestimate on how many horses this thing is pushing? I was raised on chevy's, went UA for mopar, and decided I missed the chevy's. Getting back to them and am really considering this Camaro, but wanna make sure it's not a bust of a set up.  Confused  

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Pontiacman2
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Posts: 8956
Joined: 09/08
Posted: 07/11/12 11:17 AM

What heads are on the 406????  
Pontiacman2
Pontiacman2

Professional Hi-performance engine builder

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Dave632
I mow my lawn and find Chevys
Posts: 2253
Joined: 07/08
Posted: 07/11/12 05:44 PM

Meet them at the track on test and tune day.
1/8th or 1/4 mile performance is a good indicator of HP.
Judge by the MPH not the ET. That car should run in the 110-115 mph range in the 1/4 and around 90-93 mph in the 1/8th. If it can do that the motor is making decent HP. You can work with tires converter and gears to get the ET into a decent range if it is not already good.
I would offer to pay thier expenses for that day at the track, such as entry, fuel and maybe even a burger. If they are unwilling to do that look for another car.
Here is one of my cars at the track:
MVC 019S 1  
[[SUPPORT AMERICAN CARS, STOMP A RICE CAR TODAY.]]

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TyEdUp
I love my Chevy Chevette!
Posts: 4
Joined: 07/12
Posted: 07/12/12 12:45 PM

PontiacMan, I'm not 100%sure. I wanna say they're aluminum, but i'm not sure about that. I know my way around an engine fairly well, but by no means can I look at them and tell technical things, other than the normal carb, distributor, etc etc.. I know the intake mani is aluminum and I *think* he said the rear end has 3.73 gears, but i'm not 100% sure on that, either.

Dave, unfortunately, we don't have a track within 80 miles from here, so going up would'nt be realistic, besides, i've not bought the car yet..wanted other's opinion on what they thought of the set up first.

Thank both of you....100's of views, and only two took the time to reply  

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Pontiacman2
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Posts: 8956
Joined: 09/08
Posted: 07/13/12 06:20 AM

We will need to know the brand and/or casting numbers of the heads and intake.  
Pontiacman2
Pontiacman2

Professional Hi-performance engine builder

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TyEdUp
I love my Chevy Chevette!
Posts: 4
Joined: 07/12
Posted: 07/14/12 11:22 PM

the intake is an edlebrock intake...the heads, from what i was told, was a small block 400 head that's been bored out to a 406. I went ahead and bought it 2 days ago...it's nice, but running a little rough. It had a horrible miss that was I found to be because of fouled out plugs and get this: they were the longer plugs used in a 350 block and the gaps had been COMPLETELY closed from what i assume to be because of the pistons tapping them. Now that that's fixed, its running WAY too rich, and after leaning it up to where it smooths at idle, it's still dumping too much in and almost flooding itself out and hard to start. My dad, who's been building ford engines for awhile, isn't very familiar with chevy's, thinks its partly because of the cam in combination with the double pumper 750 carb and the tranny trying to pull when in gear at a stop. We've adjusted it the best we could but still getting the almost flooding out problem and hard starts when warm. Also, it's been running without a t-stat, so tomorrow i'll be adding in a 180. We decided to do this because, as you run it, it gets hotter and cools off at idle with the fans on. He thinks this is because its running the coolant through without restriction at higher rpm's so fast its not having a chance to cool in the radiator. Any advice?  

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TyEdUp
I love my Chevy Chevette!
Posts: 4
Joined: 07/12
Posted: 07/14/12 11:28 PM

and btw, i'm by no means a huge mechanic; i can't tinker well as far as changing plugs, oil, etc...small stuff. I can usually tune a carb pretty well, but i've never owned a car with a cam before, and MAN! That cam lope sound throws my engine listening ear for a LOOP! Something i'm gonna have to get used to! Thanks for all of the help in advance and I look forward to learning from you professionals!  

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