[j69shep]

I need a solution to this problem, any suggestions would be greatly appreciated. I have a 71 Lemans convt, with a 71 455 freshly rebuilt. It has the #15 heads. My plan was to use PY's ram air exhaust manifolds to taste up the exhaust system. I rec'd them and noticed there aren't enough mounting holes in the head to securely mount the exhaut manifolds. I can get 3 bolts on the pass side and only 2 on the drivers side. Not enough in my opinion. The end holes on each side head closest to the firewall are not drilled and tapped. Are there any retro fit kits out there that will allow these heads to be used with ram air exhaust? or do I take the heads off and get them drilled and tapped? Or should I go find some original 71 455 logs and put those on? Any suggestions would be greatly appreciated. Thanks j69

[pggto]

I would drill and tap the heads personally. I think the extra work would be worth the performance gain. I beleive even the stock logs were prone to exhaust leaks with fewer bolts.

[runningbwdog]

Hi,
I have #15 cast heads on my 455. I had 1.77" exh valves installed and the holes drilled and tapped for the exhaust manifolds.
I have 1968 stock logs on it now going into a 2.5" Pypes x-tube exhaust system. The logs and the RAM AIR manifolds are difference shapes and the angles of the downpipes are different. Same goes for the 68 and 70/71 logs.
Mine runs okay, but then I never get much above 5000 rpm. Logs will probably reduce your high rpm exhaust flow.
Mike

[steve]

how much did the machine work cost to get those heads done ???

[runningbwdog]

HI,
I checked my bill for my complete engine rebuild. Can't find where I was separately charged for that work. Looks like it was included in all of the other head work I had done. I would guess $75-100.
Mike

[steve]

thats not too bad....a while ago i sold a set instead of having the work done. maybe i should have looked into it.