My 70 GS has a 71 TR code in it. I got it off a guy in Conn. from this board. I was told the engine had 10,000 miles on the rebuild. The oil was very clean when I got it and I have kept it that way. Whoever has heard the engine run has told me that it must "have a cam in it". It has an Edlebrock Performer intake, rebuilt Rochester, Stage 1 fuel pump, MSD 6AL ignition, and Poston headers thru a 3" x-pipe. As is the car ran a 13.37 with the 3.64 rear and 13.42 with the 3.08 rear. With the 3.08 rear I did the lower lift bars, adj. uppers, and air bags. These times are with sticky tires of course. OK, now here's my problem-I need to go faster!!! So, my question is; will the Stage 1 aluminum heads get me a second?? Next question; can you put those heads on a lower compression engine (like the 71 TR 8.5 to 1 compression engine). Third question; what combo of intake, carb and cam should I run? The engine runs real strong as is, so I was thinking that I could just freshen up the top end? OK, give me your opinions, expertise and any other info that will help me go FASTER!!!! Thanks!
I believe there is a thread here that talks about the aluminum heads. If I remember, they will basically between the weight savings and added HP knock about .3 to .4 off your ET.
Johnno, I think those aluminum heads would knock alot more than 3 or 4 tenths off your ET. I think you would at least be in the mid 12 with them. It depends on alot of things though. Aluminum dissipates heat alot faster than cast iron, so aluminum will tolerate a higher compression ratio. You could probably get close to 11:1 on pump gas if it was set up right. Heads are the key to increased power, but it's the combination of parts is important also. Bolting those heads on may show a deficiency somewhere else in your combination. If your compression is lower, you'll lose thermal efficiency right off the bat. If your induction, and exhaust aren't up to the task, you won't gain as much. Looks like your exhaust is fine. I'd say you would have a fair amount of tuning to do to get to where you want to go. THe compression is the big question mark. See you in Salem.
It's tough not knowing what it has for a cam. My 71 GS455, with a stock long block (although fresh) had just a reground cam, performer, stock Qjet with bigger jets and a high flow needle/seat, TA headers and 2.5" exhaust (not crossed over) and a 3.42 posi. It went 13.42 - not that far off from what you're turning. It could be that it doesn't have that much of a cam in it and if adding the aluminum heads could use even more. I think mid 12's should be quite possible. What's the story on your torque converter? That could also give you a couple of tenths.
What was your 60ft and MPH? That will give a clue as to where the car is and where it can go with just more traction, and no other changes to engine or trans. You might be able to gain some more ET here. As for engine: carb jetting and ignition timing adjustments will give you some more ET and MPH. Also, think about the air cleaner and air inlet into the carb. So far, so good (and inexpensive). Next, if you can, figure out the cam specs by degreeing the cam. Then give that and the rest of your combo to a reputable trans shop or Buick vendor to figure out the best convertor. Also, put in a shift-kit for quicker shifts. Other upgrades, before bolting on heads would be a high quality carb or performance rebuild, a B4B or TA SP1 intake. Depending on where you're at now in MPH and 60ft, I wonder if you can't knock a whole second off with the above, without resorting to new heads (yet). I wanna get a set of alum. heads too though, forgetting all the unglamourous stuff I mentioned above!!!
My best 60' time is 1.912 and usually 1.9 3,4,5 etc. Best mph is 100 and usually 99,98 etc. As far as traction I put a foot on the brakes and gas it up to 1800-2000 rpm's and at the green I slamm it to the boards and it always hooks real good. I mean I don't have enough power to have to worry about wheelspin,and just picked up a set of taller Hoosier's. I've heard that these stock or mostly stock GS's can do 1.8 for a 60' time? Will it come out of the hole better if I hold it at 2500 rpm? I was gonna try that next. Oh ya I do have a B&M shift kit, and I think the converter is a 2800???
By the sounds of it, looks like it might be tough to squeeze a full second out of it with just my suggestions. Rule of thumb is that every 0.1 improvement in 60ft. equals 0.15 at the top end. If you could get 1.71 out of it, chances are you'd ET in the 13.1 range, which is about right for your MPH. Maybe intake, carb, and cam changes are your answer without resorting to the alum. heads.
Thanks for the info everybody! Geez, what do I have to do; building a race engine is not in the budget right now. Maybe I'll pray to the Buick gods and play some scratch tickets today.
If motor won't stumble and traction is good enough, try lowering the launch rpm some, it will slow your reaction time but converter will flash to higher rpm and might help 60ft. with my car I foot brake it and leave at about 1300 rpm, the suspension seems to hit tires harder than standing on brakes real hard and trying to hold it to 2000 rpm or whatever, just a thought. Tom
