[Nyairguard]

Hi I have a orig 350ho and I benched the orig engine and had a 400ho engine built I am changing a couple of comp lifters for a quieter set anyway currently an 068 cam and wondering if its worth it to upgrade the cam got 3 on my list
crower 60916, 60242 or summit 2802
406 ci
4 speed
3.36 rear
10.06 compression
long tube headers
x pipe exhaust
12 int. 21 on dist 10 vac
750 street demon
roller 1.5 rockers
adjustable valve train
d port heads
16 inch vac @ idle
power brakes
76 cc heads
forged pistons

had 1.65 rockers on but the so called pontiac builder never clearenced for the pushrods

[pastry_chef]

Heads are unported?
Summit 2802 from your list.

[Nyairguard]

yes unported, i like the sound clips of the 2802 what is the hp increase 20 maybe?

[ponyakr]

The Summit cams are cheap. The Crower cams are High. Here's a few more choices that might work.

Lunati 10510312

https://www.lunatipower.com/street-m...8-276-286.html

Crane 283951

https://www.summitracing.com/parts/c...IaAusEEALw_wcB

Howards 410141-12

https://www.summitracing.com/parts/hrs-410141-12

If you wanna stay with the low lift, the Melling SPC-3 is supposed to be similar to the Pontiac 744. The Summit 2801 is similar to your 068, with more lift.

Sometimes the Melling cams are cheaper from an Ebay store, especially if you can find one that doesn't charge tax. Sometimes Auto Zone actually has the best total price.

https://www.ebay.com/itm/Engine-Cams...kAAOSwbFdfceWE

[steve25]

What year HO is it?

If it's a 69 then it should have the casting 48 heads with a small 66 CC chamber and the compression ratio provided by such heads can have a great impact on your Cam pick!

[ponyakr]

Originally Posted by steve25

What year HO is it?

If it's a 69 then it should have the casting 48 heads with a small 66 CC chamber and the compression ratio provided by such heads can have a great impact on your Cam pick!

"...I have a orig 350ho and I benched the orig engine..."

He mentioned that the heads on his 400 will have 76cc chambers. So, I assume that means that somebody measured the chambers.

"...76 cc heads..."

So, apparently, the original 350HO heads are still on the "benched" 350HO engine.

As most here know, by now, the static CR will also depend on deck height, as well as head gaskets & chamber volume.

He mentioned that his CR is 10.06. So apparently somebody did a calculation of it. If it was a guess, I assume it would have been rounded off to "around 10:1 ".

"...10.06 compression..."

Don't know exactly how accurate this calculator is. But it should be somewhere in the ball park.

http://www.wallaceracing.com/cr_test2.php

[Nyairguard]

#13 heads with large valves and 995 comp springs . At 1.700 height ss valves
Some of the specs from the build sheet yes my orig heads staying on my 350

[ponyakr]

Another high priced Crower cam that Cliff has mentioned some guys using in 400's is the #60243.

https://www.crower.com/pontiac-287-4...m-284-hdp.html

I suppose the next step up from that would be the Howards 410051-14, then the 041 clones. Lots of guys have been disappointed with the 041, in street 400's. Wouldn't even consider one without Rhoads lifters.

https://www.summitracing.com/parts/hrs-410051-14

[The Champ]

The 60243 is the one I went with after talking with Cliff for my 9.5 compression 462 with 2.5" RA exhaust maninfolds, #96 heads and a quadrajet. Happy with my results.

[Nyairguard]

The lunati specs look good I will have to look at the cam card, a lot of the cams are not in stock at a few places like JEGS and summit some are a month or so out ?? Only quick one is the summit 2802 only thing I don’t like is the lift seems kinda tall I think . 488 and the stiff springs from comp that we’re installed not sure if that’s too much or acceptable

[Steve C.]

If you have a verified 1.700" installed height and using the 995 springs do the math and look at the distance from coil bind with the Summit 2802 cam using a 1.5 rocker ratio !


.

[Nyairguard]

I did verify, never knew there was a calc for that .620 max lift thanks for the tip

[Steve C.]

Comps specification stating 0.620" max lift presumes a 0.060" safety margin.

https://www.hotrod.com/articles/how-...rance-is-safe/

.

[ponyakr]

"...lunati specs look good..."

You can contact Lunati to see if they have what you want, on the shelf, or when they could ship one. They ship direct.

Only $10 shipping charge. I assume they also charge tax.

Will cost more than twice the price of a Summit cam.

I bought a Summit 2802 a couple of years back. It's cheap alright. The main thing I didn't like about it was that the lobes were not nearly as wide as the Lunati lobes. I don't have a clue WHY the Lunati lobes are wider, OR if it makes ANY difference, at all.

Maybe some of you experts can explain the pros & cons of lobe width.

[1968GTO421]

Originally Posted by ponyakr

"...lunati specs look good..."

You can contact Lunati to see if they have what you want, on the shelf, or when they could ship one. They ship direct.

Only $10 shipping charge. I assume they also charge tax.

Will cost more than twice the price of a Summit cam.

I bought a Summit 2802 a couple of years back. It's cheap alright. The main thing I didn't like about it was that the lobes were not nearly as wide as the Lunati lobes. I don't have a clue WHY the Lunati lobes are wider, OR if it makes ANY difference, at all.

Maybe some of you experts can explain the pros & cons of lobe width.

Not an expert but I guess the important thing is whether the lobe is at least as wide as the lifter (for lifter spin and wear considerations). In that instance i woiuld think that wider (to a point) is better than narrower.

[Nyairguard]

was on the Lunati site ,,they are like 60 bucks cheaper than summit on the 10510312LK
cam and lifters 216.66 that's a fair price beats the others even after a Military discount. any ideas of the same lift lobes better or worse than a cam with exhaust a bit larger ?

[ponyakr]

"...any ideas of the same lift lobes better or worse than a cam with exhaust a bit larger ?"


Yeah, I assume you mean a "single pattern" vs a "dual pattern" cam.

Most all Pontiac cams have at least 6° more duration on the exhaust lobe. Many have 10° or even more.

There are some applications in which a single pattern cam is OK. I've read that when the exhaust ports have been ported to flow a lot more than stock, then a single pattern will work just fine.

That doesn't mean that the engine won't run with a single pattern cam. There have been lots of engines built using a single pattern cam. But, many of those engines would have run a little better if the correct dual pattern cam had been used.

Every time I post cam info, somebody will chime in about how they used a certain part that didn't work well for others, but worked GREAT for them, for many years.

Cam threads are notorious for having recommendations from wild to mild & everything in between. A few usually get into an argument about the LSA. Some say a street cam needs 112°-114° LSA, for good street manners. Others will say a 110° or less is better.

So, I'll just say that I'd run a dual pattern with at least 6° more exhaust duration & a 112° or more LSA.

[steve25]

Here's the recommendation for Cams that was provided to Hot Rod magazine in 1974 in a article that HO racing did for them.

If you stick close to there duration @ .050 numbers and rear gear recommendations you will be fine, but note that if you do not have the needed rear gear to run the Cam spec's listed in the hP column that Rhodes lifters will get you around that issue for the most part.

[Cliff R]

I would buy the cam separately then source out a set of genuine USA made Johnson or Hylift Johnson Pontiac lifters. Risky using anything else with a flat cam set-up.....IMHO

[ponyakr]

"...cam and lifters 216.66..."


There have been many threads here about HFT lifters.

It seems there were lots of cam failures a few years back. Many think those were caused by inferior quality lifters which were made outside the USA. You never know at any given time who made the lifters a cam company might sell, with their name on the box. Cam companies don't make lifters.

From what I've been able to find out, there are only 2 companies that make Pontiac HFT lifters, in the USA. These companies are Hylift Johnson & Delphi. I think most of the Eaton lifters sold here are made in Mexico. And I assume there are some Chinese made lifters.

Here's a description of Delphi lifters I copied from a lifter article.

"... Delphi flat tappet hydraulic lifters are available from several suppliers. These lifters are easily identified by the hardened foot on the base of the lifter body..."

I bought some Jegs lifters, because they were cheap & advertised to be made in the USA. So, I figured they had to be either Hylift Johnson or Delphi. They were Delphi. They have a groove just above the bottom, where the foot is joined to the main body.

The Jegs part number is 555-20702. The picture shown is not what came in the box I got.

https://www.jegs.com/i/JEGS/555/20702/10002/-1

I prefer real snap rings to the wire retainers. So, I bought some 5/8" internal snap rings, at Fastenal, & replaced the wire retainers.

The picture of these Melling JB-951 lifters show Delphi lifters, with the low groove. Don't know if that's what you'd get in the box, or not.

https://www.ebay.com/itm/Melling-JB-...8AAOSwk25alwJ7

Many here recommend the Hylift Johnson "R" lifters. I assume they cost a bit over $100. Don't know. They sell cheaper lifters, without the "R" in the part number.

http://toplineauto.com/wp-content/up...on-Catalog.pdf

Member here, Paul Knippen sells 'em.

https://www.facebook.com/PaulKnippensMuscleMotors/

Note: Johnson lifters & Hylift Johnson lifters are made by 2 completely different companies. Johnson does not make Pontiac/Olds HFT lifters. If they sell Pont/Olds HFT lifters, they are made by some other company, probably in Mexico or China.