Anyone know what a stock 401 dynos at the rear wheels? I'm guessing it's somewhere around 220-240? Also, I'd like to get my 65 GS 4-speed up to above 300 hp at the wheels - is this easily attainable without a major rebuild of the engine? Head work is doable (assuming, of course, I have the $$), and I also got my hands on some forged aluminum 11:1 pistons, but am not really planning on using them if not necessary due to pump-gas problems. The engine I have runs great right now (only about 40k orig. miles), but would like to add a little power without tearing it completely apart. Any input is greatly appreciated. Thanks, Brett
Brett cheapest and most easily done are changing to a q jet manifold and a 800 CFM early 70's Buick BB carb and getting the right advance curve in the distributor. 24 degrees of mechanical all in at 23-2400 RPM. You can find the manifolds on ebay. They were a one year only deal. 1966......IF you are doing a lot of road driving and want some better mileage hook up the vacuum advance but limit it to about 6 degrees, otherwise leave it disconnected. This combination of changes is very noticeable. Mike
I don't put too much faith in dyno numbers as a measure of performance. My Vette only dynos 334 RWHP/338 RWTQ and I spank '03 and '04 Mustang Slowbras that have dynoed 490+ RWHP. The dyno is just a tool for tuning, I'll have my 66 on a dyno soon so I will have a baseline for my mod plan. Artie
Brett, Bill S has had his Electra on the chassis dyno a few times...see if has it posted at Buickstreet.com. I believe he was in the 220 hp range... And as Mike suggested....a Q-jet and a quicker timing curve will do wonders. A free-flowing air cleaner is highly recommended....Stock exhaust manifolds are said to work pretty well....I don't know of much cam testing being done, so I can't say if that is worthwhile...The next step would be porting the heads, which may be more than you want to do right now... I'd love to buy those 11:1 pistons, if you'd consider selling them.:Brow: :Brow:
Brett, My 425 made 220 at the rear wheels. I have a mild cam and heavier valve springs...... that's all. I should add that after the run I noticed my fan clutch was locked up tight (seized bearing) so that must have taken away some power. Also it was running rich when wide open. I only got 2 runs so maybe next time I'll see what effect changes I make will have on the power.:bglasses:
