94-6spd

I voted none of the above. I would change that cam to a nitrous grind and spray a 2nd stage or if you have enough traction just up the jets on one stage. The nitrous grind will really react better to the 200 shot that is in there now. Sometimes you can gain 30 hp on spray without sacrificing N/A power. I have a custom ground cam for a 406 on a small base circle and a 4/7 swap that I can give you details about.

1badrz28

iTrader: (6)

I would step up to a converter built for nitrous. I was blowing through my converter at the 1000 foot mark. I could never get that elusive 9 sec timeslip. I changed to a nitrous convertor and I went 9.69 at 142 off the trailer with a 150 shot. The expensive converter is worth it. I had been using the $350-400 Super Street fighters for years. I thought they worked but they didn't.

JL ws-6

iTrader: (50)

Converter change, I'd upgrade the rear and beef the tranny up some, a better cam and more nitrous would be your best bet.

But if you're dead set on heads, screw it go all out and get a set of little chief's on there, and everything else that will be needed to go with it, cam included.

Probably make 300 hp more with those and everything that you'd need to get them to work when you're done.

RacerXLs1

iTrader: (14)

Ya i agree with everyone above. Get a nitrous converter..

Chevy406

iTrader: (12)

I haven't been on this forum for a few months, and I was suprised to see my old thread bumped near the top. Figured I should update it a little. This summer I upgraded the NOS Cheater kit to a Big Shot and a progressive controller. I played around for a while with some little 235-60-15 drag radials, but couldn't get any quicker than a 6.7 @ 108 mph. This fall I bolted on my 26"x9" Hoosier slicks and ran a best ever 6.40 @ 110 mph with a 1.48 sixty foot.


This wheels up launch is actually on the little drag radials, leaving on motor.

During the summer I spent most of my time/money upgrading my daily driver Corvette (AFR heads, Yella Terra rockers, 224/228 XFI cam).

So now I am back to planning the next phase for the Nova's engine. So far this winter I have added a belt driven vacuum pump to lower the crankcase pressure. My goal is to shoot for 600+ flywheel hp on pump gas. Options I am considering are:

• AFR 227 heads with appropriate cam
• used 18* top end
• sell my current 406 & start over

Upgrading to AFR heads and a new cam would be the quickest, and might get me to 600 flywheel hp. I have also seen some deals on used 18* top ends, but then I would also need new pistons & headers. The 18* setup should easily get in the mid 600s. The third option recently occured to me is if I sold my current 406 for a fair price ($3,500), then maybe I could afford to buy someone else's built engine. I saw a Dart/AFR/NOS fogger 406 up in TN that dyno'd 660 hp advertised for $7,500 (complete minus carb).

So anyway, I value and appreciate any ideas and comments. I am sure a better stall converter will also be on the list for this year.

AutoRoc

Nice update! This is what a good forum is about!

Car looks great and 6.40's is like 9.80's @ 140.

No reason why the new big AFR's can't make 600+ on pump. TFS was advertizing a 640hp combo with their new 230cnc heads/intake/cam package on a 406 but it was not pump gas. I'd you could make up the lost compression power by running VP113 for 20-30hp. You can still run pump gas on the street obviously but at the track and on the hose I've resorted to VP113 for the power and also the safety factor while spraying. It was worth 2mph on motor for me.

A ported Super Victor and possibly having your carb reworked(pro systems) can be worthwhile power once the combo is finalized.

Very similar refinement is what I'm doing.

Port head
Port Intake
Nitrous cam to match
Re-size carb for added airflow

My car at 3550lbs going almost 128mph N/A has got to be close to 575hp and this is off the shelf junk. After refining, I'd like to hope 625+ is attainable. Goodluck!

409CISecondGen

iTrader: (2)

You could prob pickup a few hp with the AFR heads and apropriate camshaft but it your looking for radically more power the only option is a crapload more NOS or a big effin turbo.

99blancoSS

iTrader: (115)

If you want AFR's pm me, I've got a special on them right now. I'll be topping off an sbc project with them as well.

Nitroused383

iTrader: (10)

There is no way your brodix heads are still 195 cc runners. I have read about how well some of those hogged out brodix 8 and 10 series heads can flow. If I were you I would take them to a shop and get the heads flowed and cc'd, see what they really flow, you maybe surprised. Honestly if you shop around on ebay and racingjunk.com you can find some amazing deals on used old nascar technology heads (18 degree stuff). I would not even bother with AFR 227's because I bet your heads already flow close to them. I think you could do 650 + fwhp pretty easily. Find a nice complete top end with intake, I've seen several of them packages with DEL west titanium goodies and ISKY GOLD tool room springs. This is best of the best stuff you can get cheap!

Chevy406

iTrader: (12)

I have actually cc'd my Brodix heads and the inlet runners are 198cc (+/1-2cc maybe). My pair of -8 were made back in 1981 and are stamped Slover Porting. I was messing around with Desktop Dyno, and if I use numbers like 270cfm @ .700" for my heads it gives pretty close numbers to the performance I am getting (it dyno's 415 rwhp NA and 660 on 200 hp nitrous). When I put AFR 227 flow numbers in Desktop Dyno, and increased the cam profile, it showed a nice 100+ fwhp increase over my current combination. Of course like Nitroused383 says, a killer 18° top end would make even more. Problem is many of the used 18° heads have really small combustion chambers, and might not be pump gas friendly.

I am giving serious consideration to starting a new short block build with the cash I have, and then top it off with some heads when I sell my 406. I like the idea of a clean slate build, and basing it on an aftermarket block. The 6-bolt mains on LS engines is awefully tempting, but I have to think that an LS/L92 build would be quite a bit more expensive by the time I get it running in my Nova. I enjoy the planning and building phase, so I'll take my time to research the options.

Thanks - I'll keep you in mind. Despite my lust for more hp, I am still a tight wad and like to find a good deal.

99blancoSS

iTrader: (115)

Also the SHP block from Dart offers a 434 cid SBC build for reasonable money, or a 427.
This is the route I'm taking with my 79 z28. I dont want to drop to much money on it as its my rainy day car and car to haul the kids and dog around in. But it still needs to be respectable so a 427 or 434 with some AFR's on top should fit the bill and budget.
An LS series engine of the same cubes would be a lot more money. Even more budget friendly would be a 355 with comp series 195's on top. Ported air gap intake and a Holley 650 or 750 and your good to go.

Shawn at VA SPeed has some good combination he runs with good success using Brodix heads. You could talk to him as well.

JL ws-6

iTrader: (50)

Ya can build a SBC for about 2/3 the $ of a ls motor.. wish that wasn't the case but it is.

Nitroused383

iTrader: (10)

If you want to stay 23 degree here is a killer setup http://www.racingjunk.com/post/14260...ac-intake.html

Also I seen some Sb2.2 heads that flowed 400+ cfm for around 2 grand. I'm not sure what CC size though so that might be a problem.

carzmed

iTrader: (3)

I have an Isky reduced base circle roller cam in great shape its 640 lift and 264 int and 272 exh duration on a 106. I will take $150 plus actual shipping.

347fairless

I topped mine with a set of Dart 227 cnc heads, and edel super vic intake. NX plate, 200 shot. Times below.

dacajun

iTrader: (19)

I have a Brand new Dart lil-M 434 with some Canfield heads complete with shaft rockers, solid roller. 700hp at the crank. Just thought I mention this if any of ya'll may be interested.

-Dave