I am in the process of finishing up my buildup for a max effort 355 with ported stock castings. I wanted to know what you guys think of this setup and if it will make the kind of HP I am trying to make. Here is the setup:
1. .030 over LT1 block, 4-bolt splayed main caps, lined honed, 0 decked.
2. Lunati forged pistons (11.5.1), rods, steel crank balanced etc..
3. LE fully ported heads, intake and solid roller. 240/250 @50 (650+lift)
4. Canton oilpan, Manton pushrods, T&D shaftmount rockers, 58mm T.b.
The engine is all together except for the heads which should be done this week and I will tune it on the dyno. My goal is to make enough horsepower to run 10.60'-70's in a 3,400lb T/A. I would have went with a 383 but this is my same old shortblock that had been in the car for a few years, just freshened it up and added new topend, shaftmounts, oilpan etc.. I am hoping to make about 550-575 flywheel hp so I am missing anything? The engine will be backed by a TH350, 4,k converter, T-brake, Moser 12bolt with 4.10's and 28" tires. LMK what you guys think.

 

I would guess it should be a tad over 500. Is there a point to where the stock intake becomes a restiction? I want to run a similar combo to yours. I don't have a T-brake and i'm running a 4500 stall and 4.57 28".
What engine management are you using?

 

I will be using the factory PCM for now. I have seen a very similar setup (355, solid roller etc...) put down 470rwhp with a M6 so that is well over 500fwhp with a factory ported intake. Later

 

I'm sure you'll see more knowledgeable replies but I have built something similar. Mine was a 383 but they don't make much more HP just more torque. My cam was solid roller 260/265 with about .640 lift. 11.33 static compression. We ran it on the dyno a few pulls to 448 rwhp without the exhaust on. I figure this was pretty close to 575 estimating 21% loss through the TH400 and a loose 4200 converter. The block had a cracked cylinder wall and we rebuilt with new pistons and milling heads to get 13.18 static compression. We ran the engine on the same dyno and peak HP was within 1-2 hp. I figure the limits of the intake are reached. I already have a direct port nitrous installed and planned to get past this restriction by going that route.

I'd figure with a little less cam you are going to be around 545-550 if the heads are not the restriction in your setup. I lost 15 rwhp with a full dual 3 1/2 exhaust with 5x16 Borla bullet mufflers by the way.

 

Assumming all the supporting mods are there the key will be how well the heads and intake flow together. For the power you are talking about you most likely will need something in the 280cfm range with 100% or more VE.

 

Thanks guys, I also have 1-3/4" longtubes, full 3" exahust with an x-pipe and the heads will flow over 280 so it should be close to 550fwhp.

 

yeah dont forget about the guy that got ai's setup and a ported intake . i think he made 480 rwhp but if i am not mistaken he was a manual not auto.

 

If you're sticking with the stock PCM make sure the cam you put in there will work best under 7K, there's no point in putting a cam in there that wants to be reved to 7500+ if you can only rev to 7K.

 

I would hope that 240*@.050 would make power past 7k
Thats why I had asked on management......If this is a race engine I would run some more duration....I don't think you would need that much lift but I don't know what your specific plans are

 

Clint, I can't wait to see this get done. Are you going with the steeper gears in the back still?

 

I'm in the process of finishing my 383 with similar mods and hope to make 570-580 fwhp with the stock pcm. Hopefully later on I can go to a converted carb style intake, a DFI, and a really big SR and make big HP.

Randy

 

Do solid rollers peak differently than hyd. cams? Because I have a 240/248 and its shift point is set at 6800rpms. But the redline's at 7000rpms.
-b

 

Well there are alot more to cam specs than duration@50. To really compare different cams you have to compare @20,50,100etc..I cannot spin higher than 7k so the cam is designed to make max power under the curve. I will run 4.10's out back and swap tire sizes to get the combo right on. Later

 

Clint I think that puppy will run like a raped ape!!! ;-)

Bret

 

only limiting factors I see will be TB size (maybe a monoblade in the futire) and everything in front of that (all duct work, MAF, CAI, etc) as well as the tuning getting "spot on".

If we can get the right timning and A/F while getting enough air in the intake to keep the vacuum below 1.5", we will make some real good power.

Not sure how it will dyno thru the TH 350, stall and 12 bolt but the track results will be there more so than dyno results.