I think that a turbo should be next on the list of mods. :grin: Obviously the head flow is something that can be overcome because of the added boost. Many turbocharged combinations run using a mild cam and heads for driveability and the boost takes care of the higher rpm's.
Cason, Did you get the printouts from the pull? Could you email them to me? Something is not right with those numbers. You're losing hp somewhere and it might not be the engine.
I would be happy to email them to you, but I haven't gotten them yet myself. The are supposed to be emailed to me. These runs were made on a different dyno, and the guy said that it read 5-10 HP lower than his old unit. I did lockup the converter this time, previously I did not.
Check out this cam! http://store.summitracing.com/partdetail.asp?part=LUN-33203&autoview=sku I am impressed with it because it seems to have a mild amount of duration, but a very health amount of lift, especially with 1.65 rockers. That would compliment all my high flow goodies nicely. Seeing this cam is making me lean towards a cam swap, and the $300 for a cam swap versus over $3000 for turbos helps too.
I have a lunati cam almost exactly like that one in my 72 skylark 224/234 112lsa 5 deg overlap that i bracket race. It runs 12.50's 1/4 mile on 8.5:1 compression. My plan is to get another one for the turbo skymaro. Yours will be 10 deg overlap that should still work for when you get turbo's. I assume you are still wanting turbo's eventually righto No: Anyway I really like the lunati cam I have. It seems to lend itself really well to street/strip.
Personally I'd like to see you going for more duration at 0.050" also. The cam you linked to was very similar to a Crane cam I stuffed into my mom's '79 Chevy van when she lost a cam lobe. It idled like stock, and pulled fine through a completely smogger stock, low compression 350; single exhaust, catalytic converter and all. I think all the work you've already done you will really appreciate more duration, which will move your power band up slightly to take advantage of the flow up there. Without it, the cam is getting ready to quit when the heads and intake have just gotten started. It would be nice to see the additional overlap helping to fill the cylinders better when you're spinning it up. Just my $0.02. Devon
Thanks for the replies guys. See my concern with these cams is fuel economy. I still drive this car everyday at home and college. How far can I go without ruining the mileage?
What are your mileage results at present? If performance and mileage were on opposite ends of a spectrum, then I'd say with the single plane you've got on top, you've already crossed over the halfway mark well into the performance range. Even with a 200-4R. In my estimation, until the Skylark is ready to be more of a street/strip cruiser rather than a daily, I'd stick with a stock or alum. dual plane and the 212 you've got in there now. With ported heads, more cam, and a single plane, you're pushing your power band out of daily driver status -- unless you went straight to turbos, which would compensate for the lost low-RPM low-end. Anyways, just my 2 cents, again. Regardless of which direction you go, I've still enjoyed watching your build-up, Cason! :TU:
+2. With the 850 carb and the single plane intake, I think that line's already been crossed, and the naturally aspirated combo is begging for cam timing and perhaps a compression ratio increase. Devon
I'm getting about the same mileage that I got when it was bone stock. When it comes to the carb, it's all in the tune. After I got the tune semi-close to perfect on the 850, I was getting the same mileage as an Osborne built Q-Jet. To make the tune even better I am going to pull some jet out of the primaries and add a higher power valve to tackle a lean under slight load problem.
That may help. I tune the primaries just shy of a lean stumble, relying on the power valve for a bit more when needed. I run my secondaries a bit on the rich side for WOT compensation. I'd do it differently for a track-only car, but that it is not. Forgive me, I don't remember...was the q-jet tuned with the single plane intake in mind? Devon
That's how I'm tuning. The Q-Jet had problems on the stock intake too. The Holley runs circles around it for ease of tuneability and reliability. I know, I know many people have had good success with other carbs, but I guess I have had better luck with the Holley.:beers2:
If you want to improve your economy, and upgrade your cam etc., you could start an entire other thread that can go on and on. Don't forget Obama says keep air in your tires. My suggestion is learn to tune your carb (whatever kind you use) and tune it so it flows like it's fuel injected. http://www.carcraft.com/howto/ccrp_0507_carb_tuning_tips_tricks/index.html You CAN have performance and economy within reason. Traditionally, your Holley 850 DP is a THIRSTY beast. http://www.holleytv.com/featured_landing.php?reset=true Good luck, ElectraJim
Damn, I used to have an old book titled "Performance with Economy" by David Vizard, who also wrote on the subjects of blueprinting and N2O. I can't find it at the moment. It examined the relationship between port volume and shape and how they affect flow velocity, which is the key. If you can find that book I think you'd really enjoy it. It was from the old S-A-Design series of paperbacks. Devon
How to Build & Power Tune Holley Carburetors http://books.google.com/books?id=oVZrJgUAlRYC&printsec=frontcover&dq=holley+carburetor#PPA6,M1 ElectraJim
