327/365 cam

[bossvette]

The "30-30" and LT-1 cams were designed for optimum power with production ram's horn exhaust manifolds, and the exhausts open a bit earlier as a result, to help with the exhaust port flow restriction and the stock manifolds. The 1st-design "-140" service cam for the 302, on the other hand, was designed for use with headers and open exhaust (as were the L-88 and ZL-1 cams) with a later closing exhaust valve, and that's what the '69 Trans-Am Camaros used (it was legal for '69 SCCA, as it was available over-the-counter). The "second design" 302 service cam was even nastier, but it compromised torque to the point where nobody used it - the ultimate example of "too much cam", even for a race car.

that brings back memories, I had a 1960 Vette with a 68 302 short block running that same cam a holley 3 barrel on a modified Z-28 intake 4:56 rear; after it I had a 69 Z-28 with the headers,chambered exhaust, 4:11's with the service cam. The thing I remember most about them is they were like a 6 cyl untill you hit 3000 then all h**l broke loose

 

[65stinger]

Well, I ordered the cam and lifters from O'Reilly's auto parts using the GM #'s you specified (LT-1 cam). It come to a total of $189. I plan on installing this weekend using John's procedure.......Man, I hope it works...not that I would ever doubt John's expertise, it's just I've never set solid lifters cold.....it's like someone lifting a 18 wheeler off my foot.



thanks a bunch.

 

[66427-450]

......I plan on installing this weekend .........

Remember, completely coat each lobe and lifter face with cam lube, oil the bearing journals (use white grease if you have it), then slide it in carefully. I'd stop by a GM dealer/parts dept and get a small can of EOS, and dump it over the lifters,cam,and rockers as well (if you going with new rockers/pushrods) before you put the intake/valve covers on.

also, don't let it idle AT ALL for the first ~30 minutes.... a good rule is 2500rpm for 25-30 minutes. then change oil/filter to get the cam lube out
(it'll plug up your oil filter). and I hate to say it, but most guys do not recommend synthetic oil for solid lifter cars, go with something with hi zinc content like Kendall GT-1.

 

[Hib Halverson]

Just a question isn't running unleaded gas in an older car hard on the soft valve seats, I was under the impression that when they took the lead out of the gas, manufacturers went to hard valve seats to compensate or is that an "old wives tale"?

Hib will you be attending Cruise-Fest 2004 ?

PS remember high test at 31.9

Can't do the Cruisefest, unfortunately. I just got back from driving a car we bought from PA to CA. My travel budget is exhausted.

As for unleaded fuel on non-hardened seats. IMO, this is a gray area issue. Reality is that, for engines with heads not having induction-hardened valve seats which see sustained high loads, there will be a problem with valve seat recession. For passenger cars driven in normal duty cycles, there is valve seat recession, but the rate of it is pretty slow. With a fresh valve job you'd have to drive 35000-50000 thousand miles of normal stree use to see a problem, I'd think.

Nevertheless, there is an easy solution to unleaded gas, nonhardened seats and valve seat recession. Use a product from Red Line Oil called "Lead Substitute". It's a gas additive designed to replace tetraethyl lead's lubricity and improve valve seat durability.

 

[Hib Halverson]

[QUOTE='63split]Thanks Hib,

I have a friend who has access to AVGAS that he said is rated at about 130 octane. He pumps it into 10 gallon cans. I'm not hard on the car since both the car and I are showing our age. I'm mainly a cruiser now, so a lighter mixture of 4:1 or 5:1 should be sufficient.

Mike[/QUOTE]

There are actually several types of AVGAS. The most common are AVGAS 80/87 and AVGAS 100LL. There also is AVGAS 100/130.

AVGAS 100 LL is blue and has 2g lead per gallon
AVGAS 100/130 is green and has 4g lead per gallon and is increasingly hard to find.

If you use 100/130, you can use less. Keep in mind that leaded fuel brings shortened spark plug life so use only enough leaded gasoline to keep the engine out of detonation.