Originally Posted by ap72
I agree a roller is better, but adv. duration tells you absolutely nothing, especially on cams like these. Also you state it will drive like a big cam but will fall flat? meaning you have no idea what it'll do? Then go on to suggest a bigger cam but with a wider LSA- to help make it more driveable?
Truth be told this cam will idle just like in the videos and produce a torque peak right around 4,000 rpm, peak power on a 383 will probably come in at about 5300rpm-ish. This cam is probably about the best "cheap cam" for mid range torque and a rough idle.
218º is NOT a big cam- not by any means.
I would not be surprised at all is this combo produced over 450ftlb on your 383 but only about 400hp peak(flywheel)- the torque is going to kick in hard right after your stall locks in.
Properly chosen roller can help alot in this case. But i usally suggest flat tappets.
The cam i herd on the video had a very clear lope as it went off idle. That will happen in gear and cause the problem he is trying to solve. Smooth low rpm will only come from less overlap. At 106 lobe center its going to be aLmost as ruff as what he has just more violent when it bumps in gear with more low rpm torque. Current cam is tight lobe center as well. Its going to have many of the same idle and more importantly off idle problems. Maybe some one can explain lobe center a little better its not only about duration. Longer duration with a 110 lobe center could run very smooth and still run off good numbers at the track. i am not making suggestions as this could be a tuff one to get right. Rather than throw out WAG's.
FYI i love big cams i would keep it and change out the trans to work with the gears. I am not a trans guy but i think the th700r4 can have 1.1 or better final ratio and support the correct gears. The ratios can be changed to allow it to run the 1/4 in the first three and drop low rpm in fourth. But may still bump and chunk at 55 mph if you go to far. You can also get a lock up clutch that can help with the change to high at street legal speeds.
Thats my 2 cents. Best of both worlds always cost the most. Lol its the hotrod equation. Mo money...