Camshaft Question

[celticsam]

I am looking at a Comp Cams Hi-energy cam (42-221-4) or a Voodoo (256/262) cam from Lunati. Can either of these cams be used with the stock (non-adjustable) rockers and pushrods? If not, then what is the cheapest way to make a better cam work with a 69 Olds 350? The last engine that I built, I used roller tip rockers from a big block Ford (I think...it was 10 odd years ago...) which worked well. Open to suggestions or comments. Looking for 300 to 350hp from the engine in a most day driven street car with occasional track use, so nothing huge... transmission will be a turbo 350 for now until I can find a decent 200-4r to swap in.

 

[oldsofb]

There's a thread about the Roller Rockers:

http://gbodyforum.com/viewtopic.php?p=360169

4th reply down

I run harland sharp (1.7). Part # 5017.
They are a true Olds designed rocker.
There is a Harland Sharp Ford rocker (5003) that works with Olds, but the geometry isn't perfect.
Call Bill at BTR, he always has them in stock.

http://www.btrperformance.com/products.html

A few Olds vendors have this rocker in stock. I hope this helps.

Hutch

 

[GT_80]

I have had good luck with roller tip rockers and full rollers. The caveat to roller tips is that they are not made to run with high pressure valve springs. I had 2 of the rollers fall out at the dragstrip - luckily the pins did not get into my engine, and I was able to put hem back together and peen them. After that I bought full rollers (ProForm Brand) and they worked great- They are the best bet though, gains are supposedly up to 30hp over stamped rockers with balls.

The rollers can be a bit tricky to adjust with a hydraulic cam IMO. Comp cams has very detailed instructions for adjusting them cold which work well.

I have been told that Aluminum roller tip rockers are not meant for street driven vehicles and you should use Steel roller rockers, but I had the ProForm ones in my C10 for about 4 years with no negative impact, and the rockers were still mint when I pulled them out a few weeks ago.

 

[celticsam]

So these http://www.ebay.com/itm/COMP-OLDSMO...Parts_Accessories&hash=item20ce810e04&vxp=mtr would work with no machining? I'd prefer not to pull the heads...if I do, I know me. I'll end up sinking a chunk into head work This was supposed to be a budget build...of course this was supposed to be a "drop in a good running engine and be done" deal as well...

 

[celticsam]

Interesting read, BTW...I will have to look into Harland Sharps as well...

 

[DoubleV]

Either of those cams AFAIK should work just fine with the stock non-adjustable rockers. Out of those 2 cams, the Voodoo should be the better cam, so don't go with the Comp. As far as swapping over to an adjustable valve train, the Comp roller tips are very popular for Olds; http://www.summitracing.com/parts/cca-1 ... oldsmobile

Whatever you go with, understand that 300-350 hp is going to involve more than swapping in a mild cam ( unless you go by the BS gross HP rating method ). Your going to have to put some money into your heads among other things.

 

[oldsofb]

Budget Build?? What is this mythical creature you speak of? Is it related to Bigfoot or Chessie? When you find this "budget build", take a pic of it. We would love to see one. 😀

 

[celticsam]

300 to 350 gross horsepower...goal is 250+ at the rear wheels. I gotcha on the budget. There's an 87 403 Olds running around here that was my last project (sold to a guy in Conn...who resold it). The engine started as a warm rebuild...ended up with around 5500 in the engine alone. If I do that again, I think I will no longer be married. Between the cam and intake, I should be around 325hp gross (the 4bbl engine was rated at 310hp) or slightly more. That would give me around 265 at the wheels. All give or take...all hypothetical. I'd love to have this built and driving by Fall Carslile... (for those who know what that is). Done and probably overbudget... :shock:

 

[oldsofb]

Still rockin the left over sun burn from the Spring Carlisle show. Bought a set of tall Olds valve covers. I walked for hours and only saw two Olds venders. Fusick and some other guy right next to them. GM Nationals are coming soon!

Hutch

 

[DoubleV]

300 to 350 gross horsepower...goal is 250+ at the rear wheels. I gotcha on the budget. There's an 87 403 Olds running around here that was my last project (sold to a guy in Conn...who resold it). The engine started as a warm rebuild...ended up with around 5500 in the engine alone. If I do that again, I think I will no longer be married. Between the cam and intake, I should be around 325hp gross (the 4bbl engine was rated at 310hp) or slightly more. That would give me around 265 at the wheels. All give or take...all hypothetical. I'd love to have this built and driving by Fall Carslile... (for those who know what that is). Done and probably overbudget... :shock:

You really should think of things in terms of net HP ratings as that is how they've all been rated since 72. The older gross HP are so misleading as to be outright impossible to really judge. If you were to rate that 69 Olds 350 with the much more realistic net HP ( which almost everyone goes by when talking HP ), your 350 would only be about 220 with a stock dual exhaust system. That's only roughly 175 or so at the wheels ( just a rough guess ). Adding that Voodoo would be about 30 more net HP. Don't recall you mentioning which intake you were planning on using, but a regular Edelbrock Performer won't do you a lick of good. The RPM would though. Maybe about 15 HP with your combo. Do that and you're looking at around 265 net HP with a stockish style dual exhaust off the manifolds. At this point, it would appear you have a bit more to go to reach your goal. Headers along with a good multi angle valve job and a little bowl work on the heads could give you a nice little boost and should get you much closer to your goals.

With all this said, don't feel bad if you don't reach your HP numbers. They're just numbers. Peak HP doesn't really mean squat anyway. It's just for bragging rights. It's more about torque and average HP in your RPM range that really matters.

What are you expecting your car to run in the 1/4? Gears and stall could be your savior or your downfall here.