Hi all, A question on cam selection and carburettor sizes. First the engine- '72 455 block standard bore TA 494 Stroker kit TA girdle Stud kit right thru 9.5-1 compression '74 heads TA roller rocker ass. Stg 1 valves Minor porting and port matching Custom sheetmetal tunnel ram Custom headers to suit car HEI dizzy Car weighs approx 1800kgs 2 speed glide 3500 stall 9" 3.5 gears I want a motor with looks that could kill with lump in the exhaust. Reasonable driveability. I was thinking 2 750 double pumpers atop the manifold. I posted a while back stating that I would go with a blower or a 525 Stroker kit. I had priced everything and came to approx. $12,000 AUS. I have a $20,000 budget for the whole car which needs a paint and interior so I have had to re think my strategy. With the 494 kit I am looking at $8-9,000 AUS. Any help with these questions much appreciated. Thanks, Slim
Have you thought about ditching the stroker and substtuting the new Al heads which is where the real power is. Some seem to feel they can make relatively the same power with less trouble without the stroking which is something you cannot see under the hood anyway. Look at Jim Weise's dyno number on combos with the new Al heads. Call Mike at TA and he could tell you about the trade offs. He is probably at the Norwalk event until Monday. Also unless you are doing it for the under the hood visual effect, have you considered ditching the 2 fours for one Holley 950 or 1250 Dominator. I suspect less troublesome set up while making the same or better power. Mike Tweedy on the Board who works at Year One has done a lot of work on blowers for 455 blocks. Suggest you ask him about the pros and cons.
Jim's right on the heads, lots of dyno runs & experience here to prove it! My vote is for the 1250 or a 1000 dominator... I figure you're probably flowing around 900 cfm at 90% VE?
Thanks for your comments guys. The reason I have looked at the stroker kit is because I plan to buy new pistons and rods anyway for the rebuild. I have considered the ally heads which will set me back $5,000 AUS which cuts into my machining costs a little. Been around drag racing for some years now and realise the benefits of ally heads. My father had a set of small-block chevy heads that flowed 330 cfm from George Santos. But anyway at the end of the day when all the s*#t has settled it comes down to money.
The Canadian dollar ain't much better. They're $3800+ up here not including taxes. I can buy a lot of port work up here for $1500 and get darn close on flow numbers. In the end I'd prefer the new STG-1's, but will have to wait and weenie the money out over the long term.
I ran an Offy dual hi rise years ago and topped it off with 2 Preditor carbs. Let me tell you, it was phenominal. Incredible crisp throttle response, and never over carbed at any time. They have variable venturis and flow from 600 to 930 CFM. If I were to do it over again, I would have the rectangular boxes again. Atop thier awesome performance, every was astounded at the performance a 2 barrel big block could do. And hardly nobody knew what they were sitting under that Mr Gasket street scoop. Just another option... Mike
Well, there's nothing wrong with extra cubic inches, is it really worth it if you don't have the heads to go with it ? Correct me if I'm wrong, but '74 heads aren't great to begin with and even with some porting, they'd be hard pressed to supprt 494 cubes. I know "no replacement for displacement", but it would be a shame to spend alll this money on a stroker kit and not be able to take full advantage of it. A custom sheet-metal tunnel-ram (and an extra carb) won't exactly be easy on your wallet either. Also, with '74 heads and 9.5:1 compression it seems a performer would be a better choice, but I guess those extra cubic inches make up for it some, so I can't really say whether or not it's a bad choice. Like someone said, if you're going for looks, go for the TR, but dollar-for-dollar you'd probably be better off with one the off-the shelf intakes. With 4000 lbs, a 'glide and 3.5 gears, the stroker would be a good investment, just make sure the rest of the engine is built to suit. just some food for thought. later
I am about to buy a business so I have to limit what I spend at the moment, hence the $9,000 on the engine. **** if I could, I would supercharge it with the new block and ally heads, but dreams are free. Imagine 1500+hp from a BUICK! Brien, I will have to take a foto of the heads as I think they may have larger valves than standard. But I know what you are saying bout the heads as they are real smoggers. The sheetmetal manifold is no problem as my old man makes them for any engine. Mike why don't you run that set up again? I have no experience with the predators. I remember when they were released in NZ and the interest was mixed and now you can get them relatively cheap I was told.
I guess the reason I am not doing it again is that I have so many things going on now, INCLUDING wife and kids, I do not have time to do it all. Of course, money doesn't help any. One thing about Preditors - There are only 3 adjustments made to them. 1) Air/Fuel mixture screw, which accounts only to 3500 RPM or so. 2) Idle adjustment 3) An internal metering cam that determins how "QUICK" it will open up. They are very simple carbs andin my opion, awesome for applications like you are doing... Mike
Predator carbs were big in the mid '80's on monster trucks. I thought they went out of business. I haven't heard anything about them since then. I wonder why more guys don't use them more often?
You are correct about the 80's and Monster trucks. It was the 80's when I built mine and I was at a Mud Bog - Monster Truck event that I saw Big Foot running 3 of them on a 540 motor, and I said " my Buick is going to have 2 of them bad boyz..." Of course, I had already planned and purchased the dual quad intake. I do not understand why more do not use them either. I was VERY happy with them. Actually there is a long story about how I can prove their performance if anyone is interested in it... Mike
Sorry it took a while to reply, I have been pretty busy this time of year... Years ago, while I was in the Navy, I had purchased my first Buick. It was a 1972 Skylark, 350 - 2bbl car that I was the second owner of. Shortly afer purchasing, I picked up an Olds 3.23 geared 12 bolt posi for it an dropped a stock 4 - bbl intake and quadrajet, and was loving it. I went on a cruise and decided to start my big block build and ended up spending between 2 and 3 grand on parts. Now in 1987-88, that money went a little longer way than today, and was a lot of money for an E4 to be spending... Needless to say, I was building a partly massive maching, and not doing some things that would have been real helpful. I purchased the KB Mark3H cam which was like 540/540 lift with 320/320 duration, I believe. In my Navy squadron ( The mighty Fighting Warhorses of VA-55, if anyone knows of them - probably not, LOL ), we had a mega motorhead officer that I became very good friends with. He was advising me to go with a larger cam like I did and run Rhoads lifters, as they were able to give you 2 cams in one, see thier advertising. I had another mentor that suggested that I run a dual quad intake, and knowing how Buicks loved air - I figured that should hit the spot well. Then, as I was building the motor, I was at a mud bog/monster truck event, I saw Big Foot there running 3 preditators. That is when I decided what carbs I was going to run. Now 1 mistake I made was using stock compression which I think I was at 8.5:1. But I did have a machine shop balance all internal components, along with mic-ing all assembled components before assembly. I had main studs installed also, but not head studs, and was also running non-stage heads. We assembled the motor and sat it in the car and cut the hole in the hood for the Mr Gasket street scoop to stick through the hood. Which the lower of the scoop was directly level with hood and looked nice. I will attach a pic as soon as I get it scanned. OK, it came time to fire it up and begin break-in. After 3 attempts, we had fire and had her running for a good 15 minutes to break in the cam. I drove it around the town where I built it for 2 days and was off to my duty station in Virginia Beach, oh yeah - I built it at my buddies fathers house and garage, he was a big chevy man that owned a Big A auto parts store that I had ability to purchase many items at cost. Needless to say at 6 MPG on the highway, it took me 2 entire tanks of gas to get 200 miles there. I drove it for another month and was loving it. Then out of nowhere, I was having a problem that was keeping me from revving above 3100 RPM's. It would act like there was a rev limiter and would break up bad. I had thought that I did not have the carbs in sync, although the plugs all looked to be burning great an equal. I decided to go from the dual quad intake to a single and traded off, as I was definately low on funds. I lost throttle response considerably with only 1 Predator. Then I thought it had to be the Predator, and went to a Holley 750 double pumper and lost even more throttle response. I was getting quite frustrated at this point. Then someone told me it was the Rhoads lifters that I had in becouse I could not adjust them with my stock rocker shafts. So I ordered a set of Hi-Rev TRW lifters and swapped them out. Now this was my biggest mistake as not only did I lose my ability to idle, I had basically no vacuum and lost almost all low end torque I had. I was really bumming. People kept telling me to check my ignition. I was running a stock distributor with an Accell SuperCoil. I replaced the points at this time on at least 3 different occasions with Blue Streak points and did not help at all. I had to park the car and find me another daily driver. Yes I said daily driver, another mistake I made was that I did not have another car to drive regularly. It came a time that I had to fix the problem and I went back to it. Just before trading this motor off for a very strong small block, I fixed the problem. I put a STOCK coil in place of the Super Coil and SHAZAAM, revving to 6500 with no problems. I found out that the secondaries on the super junk coil had went out. Probably less than 1500 miles on it. Man was I pissed off. So the motor was actually blown up by the guy that I traded it off to after revving it up to 8500 RPM in nuetral for the 3rd time in a row. He was running it un-capped at the header and with the stock compression, it was popping around 6500 RPM's. Let me tell you, I took this motor to 7200RPM's all the time and it was still pulling. It was awesome power all the way through. Each time I tried something to fix the motor, I made it worse, and lost power. When the 2 Predators were on with the Rhoads lifters, it was phenominal. Head snapping and crisp throttle response that was without a doubt as crisp a fuel injection if not better. So, that is my story, and if I were to do it over again, I would run that cam/lifter combo, intake/carb combo and go with at least 10:1 compression, balance/blueprint again, main stud and head stud for insurance, and would NOT - and I say NOT run any Accell product, but a MSD distributor setup. I know that I would still have a sweet street machine even today with this combo. Actually my buddy in VA Beach still has my cam in his toolbox that he got from the guy that blew up the motor.
cam Hi Slim,I would recomend a nice roller cam around 550 -580 lift and a 1050 dominator... :Brow: :TU:
Cool story Mike. Have not heard of those lifters before. I went to TA site but they only have them for the 350-400 buick. Will a roller cam be alright on the street? I want to run 2 carbies.
Poston has the Rhoads lifters listed as the same part for thr 350 and 455. A roller cam should be just fine on the street. The idea of a roller cam is to reduce friction in the valve train, I believe.
The otehr significant benefit of roller cams is that they can be built with faster ramp speeds, or how quickly they open the valve. Since the lifter is rolling along the cam lobe, the opening and closing ramps can be steeper. The advantage is that you can run significantly higher lifts without nearly the amount of over lap, so you get a big boost in driveabliity. You can run relatively high lifts as compared to flat tappet cams, and still maintain a lot of vacuum and idle now and low, and run smoothly at lower RPM.
The reason I ask all these q's is I am previously a SBC man but have now been converted so I am not to knowledgble on the buick as to cam selection etc.
There are a lot of differences between a SBC motor and a Buick motor. I would reccommend doing a considerable amount of research before jumping in to build one up. Differences like Buicks love air, intake and exhaust. And our motors do not oil as well as SBCs do, we need to do some minor mods to the block to ensure adequate oiling for performance motors. But there is an incredible amount of power to be had if they are done right. I am sure you will appreciate them. Mike
