I don't have; by any means; the will to do this. However I have noticed most of the "highly modified" N/A LT1's seem to be in the 420-450 rwhp area. I'm just curious what I would take for a 500+ RWHP N/A combination. Obviously this is with a built tranny and rear.

Let your imagination run wild with it. Who knows maybe one of you will win the lottery and put this combo in use.

Edit: Must be a street car.

 

It can be done, but it isnt cheap. If I was doing it would be a 396, pair of converted Darts or All pro Heads, single plain intake converted for fuel injection and an after market computer like a FAST running it. It can be done by all means and with a 23* head but its going to cost some green. Rather just build a 383 or 355, and spray the **** out of it.

 

I'm guessing that a 396 with ported AFR LT4 220cc heads on a custom hydralic cam revving to 6800-7000 rpm could probably make about 500 rwhp. Would this be a good guess?

 

You have to do EVERYTHING right to do it.

Basically you have to make 600hp at the flywheel.

Bret

 

^^^ I know that's why I thought this would be a great topic to discuss.

 

On a 383 ya need a set of heads that flow in excess of 330CFM. An intake that looses no more than 3% of that flow. The compression and mech roller cam and a good intake tract.

 

I don't know if this would be streetable, but here is a sure combo for 500 RW naturally aspirated LT1.

Fully forged 396 bottom end with all light weight options.

Afr 215 LT1 "raised runner" heads; a special intake through AFR is required. The world record for an LT1 was set by these heads, they flow more than the AFR 227's

Custom throttle body

Solid roller cam

1 7/8 long tube header with cut outs

Plus or minus 12 to 1 compression

A perfect tune

A stick shift with lightened drivetrain such as aluminum flywheel, carbon fiber driveshaft, and any other ridiculously expensive rotational weight reducer that could edge your way to that goal

Hope that helps.

 

Although we have not been on a chassis dyno yet I'm sure our motor qualifies. On the engine dyno, it makes 740 hp at the crank and idles fine at 900 rpm and the car will be driven on the street and road raced. It's a 6 speed. Assuming an 18% loss (that should be safe), that's 606 rwhp. Here's the combo:

396 LT1
13.5-1
GM NASCAR SB2.2 heads and intake modified for reverse cooling.
2200 cfm tb
GEN 7 DFI
83lb injectors
270/280 .720/.690 113 lsa Solid roller with 1.7/1.8 rocker ratio
2" Lemons headers
A pile of credit cards smoldering in the distance

 

Can't be a street car

 

Everyone's definition of a street car is very diff. I think dave got the formula just right.. Bad *** heads on a bad *** short block make a bad *** combo.. W/ proper gearing and i think he's going 6 speed.. that would be a damned fun street machine.. IMO..

 

I agree will illusional TA. If I had the money I would try for unlimited HP too!
However, it seems like the point of diminishing returns is around 400 RWHP

Mike

 

So I guess the best way to accomplish the task is to get a LSx correct?

 

 

i have a motor for sale that will put down 550 na

396 with pro action heads and a super victor. nice solid roller setup too

if anyones interested email me

brook

 

That's awesome!