I have a 87 iroc with these mods I would like to know what yall think id run in 1/8 and 1/4 THANKS



408ci 400 heads stock 230 duration cam@50 480 lift 1 5/8 hedders LT dual dumps t56 3.27 gear 125 shot of NOS Also what can i do to improve

 

I`ll take a stab at it (1/4), I had a similar combo..12.50-12.60`s 2.0 60 ft 112-115 mph off the bottle. 11.80-12.00 on the spray 115-118 mph..maybe someone else will chime in for your 1/8 th times. When you taking it to the track?

 

Thanks im taking it to the track a week from today What do u think aftermarket heads will do for me?

 

[QUOTE=406iroc]Thanks im taking it to the track a week from todayQUOTE]

Thats really the only way to tell. Traction and weather conditions also play a huge role as well. With the nos id say a low 12 is possible.

 

Thanks im just wanting some opinions before i run

 

any more suggestions or guesses??

 

Go with 1/2 tank or less, and make sure your tire pressure is around 20-25 psi.

 

Try the half of tank first, and if you have trouble hooking up, you might want to try a full tank. If you can hook with less gas, then do it, as a full tank is roughly 75 lbs. I'm not sure to what tires you will be using, but alot of people have an ideal pressure they run, but the problem is, every car is different. Ive tried everything from 14.5 psi, all the way up to 20. My car happens to 60' best with 18. Also the car is stable at the big end, something you will seriously want to consider. Not fun having the rear go left, and right at half track.

BTW, what intake, C/R, do you have. Your engine can really wake up if you want to step up on the heads. You say "stock" but, what are the heads from, a 400? What are your ET goals?

 

My 406 with flat tops, xe294, fastburn heads, ran 11.86 on the motor.

 

i have 10.1 comp. edelbrock RPM intake and yes the heads are off a 400 THANKS
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How much compression did u have with those heads ?? WAs u able to run pump gas??

 

It was just under 11to 1 with the 62cc fastburns. It ran on 93 octane.

 

I was told i couldn't run 64cc on pump gas with flattops

 

Aluminum or Iron heads?

 

iron

 

The Fastburns are aluminum and allow you to run about .5 more compression than iron would.

 

cool maybe i should go that route

 

I had a .040 over 400 with iron 64cc world sportsmans 200cc intakes...flat top single relief with stock rods (5.565`s) { a true 11.1 compression } with a Erson 230@.050 and a .488 lift with 1.5 rockers- wieland stealth and shortie headers ran on 87 octane with a 42* total timing and a 53 degree peak on vacuam advance for cruising...no rattles and 12.65 et`s on general xp`s. The car also ran @ 140 degress until the a/c was on. The car was near stock and had a short fill of hard block on each bank with a 780 holley vacuam secondary carb, 3.27 9 bolt axle, stock 700r4 with a l98 corvette torque converter. fast burns would be cool though

 

I found a set of used Sportsman 72cc for $500 that what i was leaning towards how much of a gain should i expect?

 

you can get new bare dart heads for a little over $600. besides you'll be swapping springs, etc to fit your cam.

 

The world or dart heads are good for 25-40 hp over the stock castings. If your current heads have the "X" after the casting number they probably have a 170 cc runner..the "x" standing for an extra 10 cc on the runners. The 200cc runner is a good match for for a street strip 400.. big difference from 5000 rpm+ range too. would they need guide and valve work? if so your looking at another 3-4 for the set ready to go + springs