SBC 421 combo advice

[redliner]

421SBC

11.7:1
23 degree heads hand ported
Single 950 4150

How much cam?

[raynman1969]

Looking for some combo advice for my build. Engine is going in a 1969 Camaro, auto trans turbo 400 3500-4000 stall approx. This will be street driven very little and drag raced. 3 7/8 stroke x 4.155 bore, flat top pistons looking to run 11 to 11.5 comp. when i was shopping for cylinder heads i was told the cam i purchased would not be correct for my engine. Cam specs 626 626 lift, 262/271 duration at .050 lsa 106 icl 102. I was looking at afr 220 or afr 235's, edelbrock cnc super victor with a holley 950xp. Lemons 1 7/8 headers. I need some advice on this cam, if it will not work nows the time to change before i complete the engine assembly and which heads would people recommend? I plan on running 100 octane on the street and 110 race gas on the strip. One last thing i have a nos kit with up to a 250 hp shot.

I went with the afr 220 and the lunati cam above. It was run on the dyno with 1 3/4 headers with 50/50 91 octane and 110 vp

[raynman1969]

The cam seems to work , the goal was to be over 600 hp. We will have to get it in the car to see if the NOS will work. With straight 110 I should pick up a little.

[wingnut]

Finished assembling my street strip 421 freshened bottom end had AFR 220s freshened went with different cam 257/263@ .050 .660intake .624 ext. 108 104 in.112 exh. Changed converter to9" 4500/4800 Old cam and car setup 253/256@.050 .573/.584 110 106 went 11.15 @122 mph pump gas and exhaust on 3200# gbody 350th 3500 con. Just fired on run stand tonight and it sounds pretty good

[raynman1969]

what kind of performance should I expect from this combo, approx. 3300 lbs with driver, 4000 stall converter, 4.30 rear gear,turbo 400 transmission.
325/50/15 m/t street R radial tires. 614 hp at 6500 rpm, 575 ft lbs of torque at 5000.

[wingnut]

It will be a blast on the street as well as the track if you plan on running at the track. Waiting to see how my new combo works out hoping to get into the 10's with it was close with old combo

[77cruiser]

what kind of performance should I expect from this combo, approx. 3300 lbs with driver, 4000 stall converter, 4.30 rear gear,turbo 400 transmission.
325/50/15 m/t street R radial tires. 614 hp at 6500 rpm, 575 ft lbs of torque at 5000.

10 flat if the car is set up right.

[raynman1969]

If I could run low tens with this combo i would be very satisfied.

[rfoll]

I suspect you will need to put some good wrinkle wall slicks on it to run in the 10's.

[67RS502]

I would expect some low 10s, mid 10s if the car needs a bit of work, in decent DA.

[GARY C]

I suspect you will need to put some good wrinkle wall slicks on it to run in the 10's.

Most people find the drag radial quicker than slicks due to less wasted motion.

[rfoll]

"325/50/15 m/t street R radial tires" ... I don't believe this is a drag radial.

[77cruiser]

DOT legal drag radial.

[raynman1969]

Went to the drag strip and car ran 11.04 at 122.7 with street drag radials set at 17.5 lbs. DA was 5500 feet so on a better day car should dip into the tens, I could also spray it and see how that goes.

[steve cowan]

Went to the drag strip and car ran 11.04 at 122.7 with street drag radials set at 17.5 lbs. DA was 5500 feet so on a better day car should dip into the tens, I could also spray it and see how that goes.

hey raynman,
i see you had crap air that day,can you give a bit more information as in launch rpm,shift rpm,and what the engine turned over the stripe ?? i understand this was your first day out with the new combo,i figured it might mph more than 122-123mph
could be falling on its face with the 106 LSA just curious thats all,
thanks