Im looking at a 383 and want to know how much of a gain is possible just switching from my 355 with a 234/238 610/610 112lsa cam. Car will be exactly the same except it will have the extra cubes and a new cam in the 24x/24x -61x/61x range

 

What does it run now?

 

7.50's @ 195mph

 

so far its gone 11.68 @ 119.88 NA on a lame 1.68 60ft with stock shocks. Im putting a th350 in and have the entire suspension done with strange DAs up front and madman AFCO rears and UMI everything else

 

Hard to say. I have changed things that have gained 50hp and only went 3 tenths faster. My last swap gained zero up top but 20hp and 15 tq under the curve and gained 2.5 tenths and the 60 foot was way worse. I would say the 383ci will gain around 30lbs tq and if the cam works with the heads/intake you should see two to four tenths faster. thats my guess.

 

The cam will actually be a custom cam from Lloyd Elliott, so it will matched to the set up and the biggest cam i can reasonably drive on the street. 30lbs Tq sounds exactly what I need to get this car out of the hole better.

 

If you are after the torque increase on your launch, You might reconsider your cam change. It looks like a full 10 degrees bigger. You might give up the torque gains from the increased displacement by installing that bigger, higher RPM cam.

 

No I want more power all the way around not just TQ. It will gain all the way around with a cam like that and Ill spin the motor to 7k or so.

 

It will gain all the way around with the increase in displacement, but that cam will lose down low. That is just the nature of the beast.

 

You are going from a T56 to a TH350 at the same time as well or will that be later? Stall?

 

Close to the same time and more than likely b4 winter is over it will all be done. Stall will be in the 4000+ range and the car will rev to about 7k. I already have the trans and shifter just need the converter for it. Keep in mind this will be a primarily track car with some street use. Its not a DD or anything like that.

 

It wont gain enough all around if I keep the same cam. With very very similar set ups and cams in the range Im looking at, cars are going mid 10s at 125mph plus. My cam is to small for a strip/street car IMO.

 

Give up torque gains due to going up 10 degrees on the cam? I'll gladly give up 40 ft lbs at 3000 rpm for another 10 ft lbs at 6500 rpm Trust me he will gain EVERYWHERE with the 383 if he keeps the compression up, especially with the 4000+ converter.

240/252 107lsa made 400 rwtq at 2800rpm and 450rwtq from 4200-5200rpm in my last 383 through a 6 speed. How much low end do you need

 

Yeah Im not worried about anything below 4k lol I just wanna go single digits any time I want!!! On spray of course

 

I think by swapping to an Auto with that stall and your engine change you could see half a second easily off your current PB.

 

Ya I think it will run 10s all day on motor and run 9s on the bottle. The car had a lot more in it than the 11.6 just didnt have enough time to dial it all in.

 

The 383 Stroker is a great engine to give you the seat of the pants Grunt power more so than the 350 Chevy. This motor can develop huge torque similar to the Big Block Engines.

Not unusual for these to go from 0 to 60 in 3.9 seconds. The 350s are capable of doing it in about 4.5 seconds. These engines can easily get 450+ HP and develop 460lbs of Torque. The car can really launch with this setup. Again matching it up with the right Transmission and Clutch among other upgrades is a must.

 

Everything will be matched for the set up. Now I just wish it wasnt freezing out side.

 

Lloyd got me some cam specs today. What do you guys think?
244/.252 .640/.640 110 LSA

 

Tight lobe separations, such as 108° or shorter, will cause the peak torque to build earlier in the RPM range and peak-out in a short amount of time. Broader lobe separations, such as 112°, will start making that torque peak later in the RPM range, but this allows the torque to build over a wider RPM range. Broader separation angles produce increased idle vacuum for more stable, cleaner, idles and better low end performance. They allow for easier tuning, as well !
You have to match the cam according to what you are going to be using the car the most.
Operating under the assumption that most people want to maximize the performance of their vehicle (as opposed to just operating the engine at as high an RPM as possible), the tire size, combined with the final drive ratio, will determine the engine speed required. For instance, a vehicle with a final drive of 3.42:1 and a tire diameter of 26” will only see about 5400 – 5600 RPM through the lights in high gear in a quarter mile run. Selecting a cam that will make maximum power in the 2500 – 5600 RPM range will provide the best ET. MPH might be higher with a bigger cam, but ET will suffer. This is because MPH is related to peak horsepower, but ET is related to best average torque in the RPM range. Heavier vehicles require a cam with more low end torque than lighter vehicles because it is much more difficult to get a heavier vehicle moving. Automatic transmission vehicles require a camshaft that has idle and low RPM characteristics compatible with the torque converter to be used.
I recommend that you don’t exceed 600 lbs. of open pressure and limit valve spring seat pressure to 240 lbs. on bracket racing applications and 220 lbs. for street applications.