Is hydralic roller cam worth $700 extra over hydralic flat tappet
(extra cost in Sweden)?!

I speaked with Comp cams yesterday and they have at least a month backlog for HR-lifters? HFT can I have on my desk tomorrow.

 

The import duty THAT hign??? find a freind here to send it to you, declare it as toothpaste or whatever....I bought what I thought was overpriced cam the ZZ9 from TPIS, but heard it was good, at the time...5 years ago...and it sure is...giving great performance, better than I"d have thought...but at your prices I"d stick with something cheaper too....gotta be a way around that....

GENE

 

What are you going to do with it? If you're drag racing for money, and putting $5k worth of high-end components into your engine, a roller cam/lifter set up just might make enough difference to win back its price, or more.

If you're just going to drive around the street, maybe a little auto-cross, etc., it's hard to justify the extra cost. For a stock or slightly modified engine, the roller set up reduces friction somewhat, giving you slightly better gas mileage and less wear on the valve train. And you'll notice a HP difference - but there are a lot cheaper ways to get that difference. If it were me (and it is, since we're rebuilding our 350 right now), I'd stick with the hydraulic flat tappet system.

Good luck :cheers:

 

I'm running a 500 horsepower big block engine and just couldn't justify the cost of the Hydraulic/Solid roller setups. Dollar for dollar you can't beat a solid flat tappet cam shaft.

 

A roller cam will make 40-50hp more than a flat tappet cam. That's about $15 per HP. Significant power gains don't come much cheaper than that.

 

Yes, A roller cam is worth more power. John Lingenfelter did a comparison on a 496 chevy (back in late 80's) flat vs roller.The roller cam made 54 more horse power. Make sure you use good springs. Comp Cams sometimes has two springs for there roller cams use the one with the highest spring pressure. Big Block HYD Rollers are heavy,and if they don't have enough spring pressure you will get valve float and loose power. Good luck! :)

 

Yeah, I read that article too. But you have to remember that that engine was set up for performance. You're not going to get that much gain from a stock engine because its other components aren't set up to take full advantage of the extra airflow from a roller. You'll surely get some, but if you're just rebuilding a stock engine, you can get ~40-ish horsepower with the right cam change, or with headers, or with several other things, for significantly less than $700. To really take advantage of a roller, you're going to have to spend more $$$ on other components to maximize it's capabilities.

I have nothing against roller cams/lifters - they make a significant difference in performance engines, and that's why racers et al use them. But if you just want to liven up your stocker, there're simpler, cheaper ways to do so.

Just my 0.00000002 megabucks :cheers:

 

Some hardcore engine builders I know they would surely go with the flat just because of the high rpm capability, remember that H.R. are very heavy and most of the time they'll fade in at around 5500-6000 rpms so I think that using a flat cam with lifters and some cheap roller rocker arms you would have a nice combo...
But if you would like to get those rollers for cheap, just choose a set from an american catalog and I'll ship them to you, no problems. Thats what we're here for, right?
Paul

 

I haven't rebuild any engine before, so I appriciate all the facts I can get. Thank U all, for the advices.

I gave Comp Cams my setup 2 times, and asked for a hydralic roller cam, anyhow (but I haven't choosed yet):

Size: 460 cui
Original Stroke and Bore +.030
Comp ratio 9.5-10.0
1.7 roller rocker arms
Holley 850DP (modified, without choke-thorn)
Edelbrock Torker manifold ( Will maybe be changed)
GM Hi Perf rectangular iron heads #6272990 (118cc, IP 325cc) Ported and machined for larger springs.
Original valve sizes.
Pistons ?
4 speed manual with 3.55 rearend, 26" wheel
Standard fuel 92 octan US (~European standard 98)
Hooker 2" headers, dual 3" exhaust
3500 lbs
2000-6000 rpm
Application: Weekend HP street machine.

And they gave me two different suggestions:

XR282HR 2200-5800, 282/288, 230/236@.050 .510 lift
280HR 2000-5500, 280/280, 224/224@.050 .566 lift

What do you think, dual pattern or not? My heads E/I @.400 are 75 %. Does it mean, good exhaust/intake relationship ??! and should I go with singel pattern then? It has alot more lift too. http://www.chevyhiperformance.com/ed...2218&sidebar=1

Or shall I go with hydralic flat tappet :confused:

 

If you are only revving < 6500 then you are within the hydraulic rollers RPM limitations, so that is not going to be a disadvantage.

Those cam specs they gave you for the XR282HR are wrong, it has a lot more than .510 lift. The small block XR282HR has .510 lift on the intake, more on the exhaust. I'm sure the big block version has even more lift than the 280HR.

AFR heads have one of the highest E:I ratios of aftermarket cylinder heads, and according to them, their heads run better with split duration (larger exhaust) cams, so I'm not convinced of the E:I and split/single pattern relationship. At the least, other factors like compression, exhaust efficiency must come into play.

I think if the extra money is worth it or not depends on how much money is worth to you! You'll make more power and run more efficiently (better gas mileage) with a properly sized roller vs a flat tappet. If I were you, I would call a few other cam companies, Crane, Crower, Lunati and see what their recommendations are. And if you do go with roller, do a lot of research on the lifters and go with a brand with a good reputation. With your beautiful vette I would not skimp on anything, but that said, you may have better uses for that $700.

Those headers sound a little on the big side, don't you think?

Rob