oldzy

Doubt I will go headers, weld the exh. divider, etc. (at least not right now). With that in mind... 3.42 gears, dual exh., ~9-9.5:1 CR, summer daily use with some very occasional drag racing... and an otherwise stock engine... what 'flat' tappet cam below would be the better choice? I know I am going to hear the' custom grind' is the best from Mark though thx


-Comp Cams-




-Engle-




-Lunati-

doubleclutch

I'm building a 403 for my '79 Trans Am. I have been scouring the net for a good all around cam. I have settled on the XE262, unless someone can convince me otherwise.

Shizzy

I'm kind of confused by your "stock 9-9.5 : 1 " stock is only 8.5:1, if you have changed that then its not stock.

oldzy

Other than a new cam, as well as pistons/gaskets to get ~9.0:1 - 9.5:1 CR, the block/heads/exhaust will be stock.

71 Cutlass

I'm using the Comp Cam XE262h, so it's either that or one you did not list...the Lunati cam just below the 318A3, which is the 318A2. With no head work, something "Bigger" won't mean much. I hope by "stock" exhaust you are at least talking about duals.

Double Clutch: If you have compression in the 9's or low 10's and have gears in the 3:23 and up range, along with some head work on your 403 I would go up one notch in the cam you've chosen. Since I do not know what's been done to your engine, ignore the suggestion if it does not match your combo.

cutlassefi

I still don't understand why you guys are hell bent on running fast ramp cams on stock iron headed application with ample compression.

Knowing what I know, I just don't understand.

oldzy

to annoy you

Fakser

Even though I know a lot of people are not favorable towards Mondellos, this is the cam I purchased from them.

Part #
(Hydraulic)Intake
LiftExhaust
LiftAdv. Int/Exh
DurationIntake
@.050Exhaust
@.050Lobe
SeparationRPM
RangeNeed help?
Call us!
(805)
237-8808Camshaft
ApplicationLiftersSpring Kit
ShallowSpring Kit
DeepTiming
Chain SetRocker Arm
KitSpring Pres
@Seat (lbs)Spring Pres
Open (lbs)JM-18-200.4880.496260°/266°216°226°112°1000-5000
$149.00 StreetHL-230
555-H
555-HCRSK-247-SPSK-245-DTR-252
TR-499ARK
SAR110-140290-340

If it irks you that much to do business with Mondellos the same cam can be purchased from Engle racing since it is made by them.

However I do not have the same build as your engine I have a tad more in being .030 over flat top pistons, roller tip rockers, Edelbrock performer RPM intake, mild polish on the heads (means I did it myself as best I could) 600 cfm #1405 edelbrock carb, double roller timing chain. All sitting in boxes waiting for me to get some vacation time to put it together.

Fakser

the format didnt copy the same but it is the JM 18-20

cutlassefi

Point taken.

Based on our conversations, and basing it on the fact that you were just looking for something a little better than stock, other than the one I recommended from me I'd go with the Engle.

doubleclutch

I'm still building a parts cache, because I like to do the homework on the front end. This will be my first build since college, so I'm not claiming to be any kind of expert, but I do glean a lot sifting through the babble on these forums. My plans are as such:

Q-Jet Stage I, electric choke (already on car)
RPM manifold with WFO air cleaner base
Ram Air Resto factory "headers"
#7 heads with 403 valves w/ adjustable valvetrain installed (cores n hand)
factory deep dish pistons
Comp XE 262 (with 80% certainty)

I may have the deck block zeroed, depending on how things look. I've got a good Olds guy in my neck of the woods (Atlanta). Since I'm a good six-months from doing anything at all, right now I just read the arguments over camshafts. Both entertaining and enlightening.

I'm still driving the anemic thing around with a 2.41. The car has 107K on it, but I do believe the motor has been out before, because it has a little bit of a lope to it, and some dumbass painted the engine gold. I just rebuilt the front suspension, and in July I'm replacing the frame rails, floor pans, and changing the rear gears to 3.42s. I'm seriously considering a 200R4 transmission as well.

oldzy

I think in my case... I am going to take my heads to the machine shop FIRST... b/c those are the things that will/can be changed the most. I will listen to the machinist, see what he has to say. Who knows... I might end up getting bigger valves, porting, welding of the center exh. area, etc.

Once the heads are done (either just cleaned up and/or modded), THEN I will know for sure what cam to get, whether I want a custom flat tappet, off the shelf, or a custom Chinamen roller cam. They might even say the 4/7 firing order swap is the greatest mostest thing.

doubleclutch

Yeah, we're kind of in the same boat, maybe a Chinaman boat . Like you, I'm trying to formulate a strategy while remaining flexible to new information.

What is the 4/7 firing order swap? I've not come across that yet.

oldzy

cutlassefi will prb answer, as I only heard bout it recently from him. Apparently, you get a 4/7 cam... then it is a simple change of the firing order by swapping spark plug wires. No mo 1-8-4-3-6-5-7-2. It becomes 1-8-7-3-6-5-4-2 or something.

I am hesitant, as I don't want to explain to every/any shop/dealership I go to to get work done that the firing order is not stock. And although I have done it before, I don't really want to custom cut a few plug wires to fit better either. I might even go back to points, stock/orig type plug wires, etc.

cutlassefi

The only U.S. made Olds roller cores available right now are only offered in the 4-7 swap, all others are made abroad.
Personally I don't see a problem, certainly no less than all the 4-7 swap cams Comp has produced and sold could create, just take a look at their catalog, they have a bunch. But everyone is entitled to their opinion no doubt.

Just know that in choosing a fast ramp cam, Engle, Comp Xtreme, and Lunati Voodoo, they can be on the noisy side sometimes. See below;
http://72.22.90.30/phpBB2/viewtopic.php?t=76623

Something you'd probably want to know going in.

oldzy

Also... if I get the 4-7 done, drop dead the next day... the new owners will have a hell of a time figuring out WTF is wrong if they pulled the spark plug wires w/o looking where they went first.

I would almost need to put a note under the hood somewhere w/ pic/diagram even... but that would look gayy of course. Techs prob still would not look at it though. Reminds me of posing a multi-question email to someone, and they vaguely answer just the FIRST question... or ordering from a certain repro co... I tell them many times to send via Fedex taxes/brokerage incl. with a tracking#.. and of course they do neither (even though I have ordered from them a dozen times at least). Oh but I get the tracking # after I already received the package and after sending 12 emails.

oldzy

Maybe a roller is overkill for my setup anyway? ie. b/c of likely stock heads, exh man. etc.

The 'fast ramp', 'off the seat time' lingo is Greek to me. I am assuming you could order (equiv to the 4/7 roller) a custom Erson (can't find anything Olds cam related on their website, nothing bout reto-fit Olds roller lifters, etc.) flat tappet that is geared specifically towards stock iron heads, and will not be noisy? Only benefit to me is saving some $$$.

Hopefully, I can get to the machine shop this week and get their input... then I can decide whether to get a custom roller from BTR, a custom Erson flat tappet, or one of these Engle/Lunati Voodoo cams.

captjim

http://www.realoldspower.com/phpBB2/...ic.php?t=28012

My 9 to 1 355 with a 16-18 cam. Spend the extra $350 for a street port job, IMHO well worth it.

oldzy

Thx. Never heard of the Classic Cams option. Found it in their catalog. Seems a little big for my basically stock engine though? Will be running stock int/exh. manifolds (dual exh. though), stock heads, and aiming for 9-9.5:1 CR.

bccan

Just a few more cents thrown in here, take it FWIW. If you are collecting parts for a build to be done down the road, even if it is only a few months, I think it makes sense to spend the extra money & go w/ a hydraulic roller cam. Arguably better specs & performance, greatly reduced friction, no oil issues. Yes it does cost more & to do it right takes one machining operation (not absolutely necessary) but for the short & long term isn't it worth spending an extra grand to have the advantages? Many do not think so, but there are plenty who do, you might guess that I'm one of them.

Oldzy - Be very careful not to over cam that engine! The 3.42 helps things but your engine combo is going to be pretty mild - doesn't mean it can't accelerate very respectably or lay down some nice rubber but you want to optimize it for the operating environment most encountered - 1800-3000 rpm at which I'm ASSuming it will operate 90% of the time. Look @ Engle RH 6-14 or as a stretch RH 14-22 or some roughly equivalent sticks from another mfg. or maybe...Mark could spec one, or someone else who deals w/ a lot of custom cams, roller or not. Roller is not necessarily overkill, they were designed for efficiency & an evolving world of engines, it just has to be sized & spec'd correctly. I have and/or deal w/ a number of small block cars & see one in particular that is overcammed, believe me you're better off missing just a little low than a little high.

As far as your head work - Fill the crossovers, light port and/or big valves. Weld the divider now despite manifolds because odds are once you get some nice acceleration out of that car, the "fever" will probably grip you & you are going to be typing away doing header research. I think my kid's car w/ manifolds is actually louder out the tailpipes @ idle/low speed than my car, both have same exhaust after the manifold/headers. He just brought up headers the other day, coincidently 2 weeks after his first time @ the track where he put down some 14.6@95ish runs.

I can give you some examples of cam sizing if you wanna hear more, but look @ CaptJim's build & see what has been used & what it can do. My kid's red car in sig has an engine very similar to what you are doing. Compare the cams you are looking at w/ the blue car build in my sig, I didn't build to get dyno #'s or track times, built for great driving manners that can coincidently put down good #'s on track rental day.

Doubleclutch - I think you can use the "bigger" example due to displacement once you "gear that rear" but all the same parameters still apply. But my opinion is to generally add lift, not duration to these cams if they are doing primarily pleasure driving duty. They'll go decent enough in the upper end but to me, more important is the initial acceleration off the light & low/mid range snap for fun & passing!

Joesw31 - I think that cam would be big in either of these cars - I'm thinkin you are a manual trans guy.

oldzy

Thanks for the info.

I am going to be getting Speed Pro 2321 6cc dish pistons, then appropriate head gaskets to get the desired 9-9.5:1 CR.

I was going to go the hyd roller cam route, but too expensive. I could afford just that and roller lifters and springs, but that is about it right now. I want to get a few more things like the exhaust pipes/mufflers. Plus I don't know how much the machine shop is ultimately going to charge in the end for degreasing, boring, installing springs, etc.

Other than new pistons... the engine/heads/manifolds will be otherwise bone stock. I highly doubt I will have the crossover filled, divider welded. Reason is that if that was done, I would/should run headers... which defeats my 'external originality' goal. I have a 3.42 posi, but I am still undecided on rebuilding my blown TH350, or getting a Muncie M20.

cutlassefi

You have more cam than he is thinking about, that makes a difference. Having a 4 speed helps too.

I'd keep it around 9.5, jmo.

Run to Rund

If you check the Comp lobe catalog you will see that their smaller extreme energy, etc. cams have less aggressive ramps than their big ones. The less aggressive valve motion gives cams that tend to be quieter and last longer given the problems today in getting good additives for your engine oil.

cutlassefi

An example? I see virtually the same adv to @ .050 spread for all Xtreme lobes.
Also it's an assymetrical closing ramp that can add to the noise.

oldzy

So does this mean roller cams will be really noisy b/c they are more 'aggressive'?

mikey g

Ok so for a stock 72 350 supreme what cam and lifter set would require no other mods aside gaskets?

cutlassefi

Over aggressive yes, aggressive no.

For a stock application lifts should stay around .500 or less, and aggressiveness should be kept to a minimum when using stock springs.
Otherwise duration will be determiend by engine/vehicle mods.

Jharken

IMHO I like fast ramps because you can keep seat timing short and still get more rpm with less compression.

That's why solid flat tap and roller rule for hp.

It is more of what the purpose of the build is than anything.Street manners and longevity are you're friend with old school ramps.
Jim

cutlassefi

Jmo but not sure you thought this one thru J.

Jharken

Example:you use a 268@.006 hydraulic flat tappet slower ramps you get 220 @.050 about 5250rpm peak hp with 350 cubes and duration at .200 lift about 130. and 48 intake lobe intensity.

268 solid flat tappet valve lash .020 239 @.050 - 10 degrees for lash= 229@.050 if compared to a hydraulic cam which would be 450 rpm more with the same seat timing not to mention more .200 lift were the valve spends more time. I meant if cams are equal at the seat with same compression.not low compression oops.

Jharken

Also no were did I say hydraulic roller.

cutlassefi

I disagree J.
If I understand you correctly you're comparing two different cams. A hyd with 220@.050, vs. a solid with what you believe to be 229@.050, 9 degrees will make a difference. As you mentioned the solids' "advertised" duration is taken at .020 tappet lift, not .006 like most hydraulics. So by doing that the solid will automatically "look" faster because of the narrower advertised, vs. @ .050 than the hydraulic given.

The best way to verify this one way or another would be to take the same cam and run it with hyd lifters then solids. Most of the generic stuff (204/214, 214/224 etc) have lash ramps on them. Maybe someone who has one of those could do the comparison. I believe the solid will rpm higher/faster but I'd be hard pressed to believe the power would be anything other than virtually the same.

Thanks, jmo.

Bunser

Where the hell were you guys when I was having my engine built...
Oh yeah, I wasn;t a member yet...damn it all anyway. Live and learn.

1968 cutlass

My machinist actually recommended the next 1 on the list 42-223-4, and i just spoke with a guy at Comp Cams, and he actually recommended the next 1 after that 42-224-4, said it would perform well on the street good cam for standard transmision and would have that noticeable lope sound and have have nice performace as well... anyone with experience with either of these 2 cams

cutlassefi

Imo neither one. I still don't know why people insist on putting fast ramp cams in stock headed 9.0:1+ American V8's.

1968 cutlass

well, I'm all ears, b4 i spend money in the wrong direction. I have a sbc currently installed that has that nice lope sounds (assuming that is from the cam) have no idea what it is... but would like the same sound and performance in the olds 350 that I'm building. Every forum has such varying opinions...

cutlassefi

O.K I guess I'd have to ask what's more omportant, the lope or do you really want to make some power? And do yourself a favor, unless they're ported don't compare your Olds heads to the Chevys.

1968 cutlass

of course power would be the goal not just sound, but I'm not interested in anything that will not be reasonable as a cruiser either... I can get #5 heads for 75 a piece, and since i don't have the valves for my 7a heads, the new valves alone would run me that amount... but no one will answer whether I will definitely need to have the seat replaced with hardened seats... all of this of course is strictly about the heads, just 1 of the daunting decisions i have to make... what would you suggest i do to match the sound that fast ramp cam would provide with power as well... I'd actually prefer speaking with you in person if you don't mind, i can give you my # or how can i send it privately