Well it all depends on the engine car combo. I had a very radical 273. I even tried porting and opened to the max the stock manifolds, ran 2 1/4 pipes and muffs back in the day. Then I went to fenderwells I picked up 55 hp at 7500 rpm and about 4500 power was up 22 hp.
Now I run a 416 that is very stout, I can not even imagine making that think choked up with stock ex. I run the TTIs and 3" pipes. What comes i nmust get out, and you can not flow that much air on those stockers. It is a waste of $$ after you have custom head work, large intake, carb et. It was a bottle neck for me.
I will tell ya, is was a mother #%#%@ to put them on. I also had an issue that they guys at TTI said they had not hear. You can not get the top trans bolt in to the trans on the driver side that comes in from the front, the larger 7/16" bolt. When it is in the starter housing hits it. I have moved in every direction the clock on the starter and there just is not enough room.
I even milled the head of the bolt thiner, tried a pan head, hex head bolt and tried best I could to mill the face of the block to allow the bolt to sit farther in away from the starter. it is a no go!
If you have the engine on the stand I could have shaved a 1/4" from the block and it would have made it.
Now maybe it is a combo of 2 things?
1. My block is very think on the casting, I looked at the ol 273 and a 318 and this 340 is much thcker on the block for both side front trans bolts.
2. I also run a 727 not a 904. There is about no room at all.
I had to make an access panel in the floor board to hook the kinkage, trans lines etc. Routing of the floor shifter cable wa very tuff too. I made it removable so that the carpet can be pulled back for service etc.
Lastly, they supply a stud/thin nut for the top starter bolt. You have to somehow get the nut started with the starter part way over the stud, then gradually work the starter back as you tighten. Well this took about 5 hrs and I had to turn an 1/8 at a time, once from under the car, the on top, then under etc. you get the pic. All this with the steering and master still out of the car to allow some access from top.
Worst headers I have every seen to put on. Bottom line, there is no room in a 64 with a 727 and power steering. Looks bitchen, works great once in, but man you need a lot of beer.. .the Beer was more than the heasders LOL..
So to your point, well I guess some body needs to take a 500 + hp stroker and put it on a dyno with stcok ex to test the power diff VS the TTIs.
Anyway great point you made..
