Originally Posted by
velociabstract
I haven't looked at out cam profile so I'm assuming a lot. However, since I made no real power it's obvious to me we have no overlap to speak of. Impressive flames didn't shoot out of the open headers at the end of the dyno run. No overlap. Have a real detailed talk with the header designer, show him my photos and tell him my results is all I'm saying, before getting too far into this venture. Have him take a look at out cam profiles. If after all that he's sure, go for it and I'll rub a rabbits foot for success. All I want to know is how in the world are the E55 guys getting 70 hp from headers. (thats what sold me BTW)
Les
The M113 4.3L V8 is the exact same as the M112 3.2L but with 2 extra cylinders. This site is saying that the 430 has 78 degrees overlap. Not sure on accuracy.
http://www.marcusfitzhugh.com/CLK/DIY/camspecs.html
The E55 guys and the random NA V8's here and there making tons of power from this is why I am doing it as well. I forget the numbers but an R230 SL500 made 35-40whp throughout his entire curve and the company was saying the system was designed for torque! It was like 50-60 ft-lbs or something.
Originally Posted by
oledoc2u
Well, I knew Les would chime in, since he has been there done that. Just so you know, about 45 min from me is a shop who have been building headers since the early 60's, from monster truck to some of the best drag racers in the world. Our problem is not just the fact we are not going to get a big return, but the room to even think long tubes. Their quote to me, and I love their work, was 2500 bucks. I would have done it for half that, but for that, I am doing a gear change in the rear end. As for shields, not even room to place your fingers in there let alone a wrench. So clearances are a huge issue, that is why I stated the heat issue as you are very close to everything trying to get down to where the collector will be. Once you are at the collector, then it is muffler shop time....no biggy there...
I will add this...in all my old days of muscle cars, headers were usually in the mix of mods we all did. They were always a pain from the burns we all had working around them, but they did add some HP....but 70 is ridiculous... Everyone car manufacturer in world would put headers on their performance cars if this were true. Think about that for a second. 20-30 is and always was max in our day...and I can't see that changing today with computers no less....
The thing about it is my welder is a great welder, single, has a rig in his garage and will damn near do anything for a friend with a 12 pack lol.
We will deffinately have some playing around to do with fitting but I am worried about heat too. S**t my underhood temps shot at minimum 50 degrees when I put the V8 in.
The 55K's really are making that though. Someone did some serious homework on it that is for sure.