Chevy 400 Build

[LilSpann601]

I went ahead and took your advice Chevy and ordered 2 bolts from ARP...Should be here in a couple of days

 

[LilSpann601]

 

[LilSpann601]

Update: I made a mistake and sold the vortec heads I had...I will be either finding some more vortec heads that are complete or im going aftermarket. As for as cams Im still trying to see which cam im going with...since doing some research I see that lunati makes a cam called lunati barebone 280...its lift is .480-.490.... Will a cam around that range have a good noticable lope to it...

 

[mebe007]

what are your plans for the motor? those are mild lift #'s

 

[CHRIS.O]

I looked that cam up on youtube and in a 350 it barely had a lope so in a 400 it would have 0 lope. Obviously a cam shouldn't be picked based on lope but if it is that important to you then no, no lope. Also I see you wanted to run vortecs. You are restricted on lift running vortecs without modifying the heads or buying a particular bee hive valve spring made to fix the issue of not being able to run over .470 lift. A 400 is going to take quite a cam to get it to lope good and make good power and that cam will probably not perform well with stock vortec heads. Re think your head choice.

 

[Pontiac455]

I would go with a set of AFR 195's with angle plug and 64 cc heads. Eddy air gap rpm intake and 750 HP street. Run that cam with a set of voodoo 1.6 roller rockers.

 

[chevy2480]

Well seeing what your goals as far as hp. Running that cam is going backward. At that point. Figure out your heads then have a cam built for your goals.

 

[LilSpann601]

My hp goal is around 400-500 hp. I doubt this car would see a strip. I just want a powerful street machine with a mean lope but I still wanna run AC. Should i stick with the comp cams big mutha thumper cams. I am going to go with the assault racing heads the lift is good to .650.

 

[1badchevy]

Be VERY careful changing heads on the 400 sbc. Because the 400 was a small block with such a large bore, the 400 heads were specially drilled with steam holes to keep them cool. If you change heads and dont drill steam holes, you are garunteed to overheat.

 

[CdnCutlass]

I see there has been a lot of discussion on steam holes, I will offer another perspective. The machine shop that built my 400 has built a lot of 400's for racing, specifically circle track. In his experience steam holes are a weak point and typically the blocks will crack at the steam holes. So every 400 that he does he welds plugs in the steam holes. The steam holes on my block are plugged, can't speak to the longevity of this modification because the car is still ripped apart for body work.

Well, you will have to keep us updated on how that works out for you. I have never heard of anyone intentionally not using steam holes and I could only possibly see this in a drag racing set up but anything than runs a duration seems to me it would be an issue. My first 400 I drilled steam holes in my Dart sportsman heads and never had an issue with cooling or cracks around the steam holes but this was in street car.

Thought I would update on the steam holes. After driving about 1500 miles this summer the car has had no issues with coolant temperature. A few times have driven the car for three hours at a time. While in motion it stays at 180-185 degrees. The most I have seen it climb to is 210 on a hot day idling in traffic. For a cooling system I run a stock water pump, Summit 2 core aluminum rad, 16" single electric fan and 50/50 water-antifreeze mix.