Indy 426-1 heads what to expect

I am looking to build a 800hp gen 2 Hemi and waslooking at the Indy 426-1 heads. I have used the 440-1 and 440SR heads in the past on builds. What "pit falls" will I run into with the 426-1 heads? Will stock type intakes work on these heads?

I built a 604 pump gas engine with 426-1ra heads unported,single Dominator,Cam Motion roller that made 825 on pump gas on an accurate dyno. Has gone 9.70@ 138 in a 3400# car. Just match the heads to the engine size.

I'm not sure if you could get a real stock type manifold to work on the Indy heads. They use a valley plate just like the wedge heads do. I've used the valley plate and Indy manifolds on stock type heads, but not vice versa. I think you'd have to do some milling to the bottom of the manifold to get it to clear the valley plate.

Why would you use -1's instead of Hi-Po's?

They are heavy for one, they are an inch wider when assembled on an engine over stock heads, they are taller, and in unported form, not a lot of fun. Maybe a little over 600hp on my 484 Hemi....Went 10.7 on my street/strip car.

I had a set. I ran them for years. I was never impressed with the flow numbers or the performance. I ended up porting them just to get 398cfm out of them, but the big valve Hi-po heads just kill them. We will see what my 605 runs with those on it, but flow wise, How about 458cfm....And they are a lot lighter.

Should be interesting.

My HiPO's OOTB flow 443cfm@.700 corrected, no porting or cleanup. Dave

Thanks for the replies there a few sets out there that can be bought pretty cheap sounds like the Hipo heads might be a better option

Thanks for the replies there a few sets out there that can be bought pretty cheap sounds like the Hipo heads might be a better option

Do the HiPos have the same cast in rocker shaft stands that the 426-1s do?

Nope, uses all the stock style stands rockers and valve covers, bolt in replacement for stock heads. The exhaust valve is rotated upwards 1.5 degrees for valve to valve clearance for the 2.4" intake valve. I found that my piston to valve clearance was better than with my old heads. Dave

The HiPos are the Canfield heads. They are high flowing stock replacement style heads, much like Stage V. Indy bought the molds when Canfield went bankrupt.