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I'm sorry to ask this, but what do you mean by 'a slippery slope'.
I searched the idiom on the internet. It says:
"A course of action likely to lead to something bad or disastrous."
Do you mean that the chances are bigger that something bad will happen to the engine?
Or do you mean ones I go down the Roller cam road it will be costly?
Sorry It is probably an american hot rod idiom:
HP is a slippery slope.
Once you get into the mindset that the HR cam is only $1200, and it's worth it....
Then you may as well add on roller rockers, and then taller valve covers, and a better breathing intake, and, and.... etc.etc.
There is no end to that black hole of mods, except for the size of your wallet!
HP is costly.
How much do you want? And how much do you want to spend?
HP rule #1.... There is always some guy with more....
If you have a spare $200,000 lying around, you may as well go buy a new 1069HP ZR1 that does a 9 sec qtr mile and 215mph!
They look like a fighter jet to me. But they are hard to beat at any $. And come with a warranty.
But a C3 is still one of the most curvaceous and beautiful cars on the road!
It has never been beat in the looks department, even after half a century.
no! Arp bolts are not an overkill. They are required. Never use stock head bolts on aluminum heads, ever.
The arps bolts have a built-in washer head plus another washer & lube to make sure the head of the bolt does not gouge the soft aluminum.
They are pricey. And that is why it's part of the "hidden cost" when switching to aluminum heads.
Sorry It is probably an american hot rod idiom:
HP is a slippery slope.
Once you get into the mindset that the HR cam is only $1200, and it's worth it....
Then you may as well add on roller rockers, and then taller valve covers, and a better breathing intake, and, and.... etc.etc.
There is no end to that black hole of mods, except for the size of your wallet!
HP is costly.
How much do you want? And how much do you want to spend?
HP rule #1.... There is always some guy with more....
If you have a spare $200,000 lying around, you may as well go buy a new 1069HP ZR1 that does a 9 sec qtr mile and 215mph!
They look like a fighter jet to me. But they are hard to beat at any $. And come with a warranty.
But a C3 is still one of the most curvaceous and beautiful cars on the road!
It has never been beat in the looks department, even after half a century.
Hm my max. $$$ for the engine project would be: € 3000-3200. (With € 3200 being really the maximum.)
When I calculated the totals I was amazed about the total price of the Roller cam. option... I find it very expensive, and I feel that option won't give that much HP/torque+ when comparing Hydr. roller versus Hydr. flat tapped.
I do about 800 miles a year with the car (An combination of 'chill cruising' & 'sporty driving'). Are the rollers really worth it for the miles I do?
Last edited by Novusuhu; Aug 18, 2024 at 12:12 PM.
The thing is, I think a lot of people overlook the importance of a reliable and stable valvetrain. Falling short of achieving this and you'll not extract the potential from your heads and incur many more expenses chasing the problem. If the heads are good flowing and you paid for that then that's $$$ wasted if the valve train cannot deliver the flow to the head.
Make it a good, stable, reliable valvetrain. Then you will not have to worry about it or treat it like it's glass to keep it going. 3/8" rocker studs are fine for low perf cams and low spring pressures. So for stock or near stock flat tappet they are fine, Beyond that you'll want 7/16" for stability. Using a flat tappet high intensity, extreme energy etc, cam I would also use 7/16" studs.
The number of degrees between the advertised duration and the @.050 duration gives you an idea of the intensity. The lower the number the higher the intensity. The one you have selected as flat tappet is 44*. That's very intense for a flat tappet. For reference my ROLLER cam has an intensity of 51* and it took 7/16" studs to get that under control. Those rocker studs flex a lot more than you would believe.
Steel roller rockers can be used with stock valve covers, it's what I use. Or aluminum ones can be used with spacers to lift the valve cover a bit higher to clear the rockers.
It took me a few iterations on my engine to get it where it needed to be and is now. And extra money spent to do it. Crappy heads will bite you every time. Poor valvetrain stability will as well. I got both first go at it.
It's just very hard once you've spent the money to incur a failure because of something that could have been better, but the $$$ dictated the quality or robustness of the components. Many folks throw in the towel at that point, or just sell the vehicle, or park it forever believing someday they'll get back to it and never do.
Time spent researching all of this is time well spent.
Whether roller vs flat tappet is worth it to you or not is your decision. Research, get the pros and cons and decide.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
My last build was $10k the first time.....then those Mahle bearings delaminated.....runs incredibly now and it's solid flat tappet....
Lots of ARP stuff, head studs, crank main studs, etc...
Ok so now we have a budget.
And it is the "combo" that counts, not any one item.
Budget:
And let's try to stay away from the HR cam, for $ reasons.
Stay away from all the ARP bling, except the head bolts, those are a good idea.
Heads:
Your stock 882 heads do not flow well, have small valves, and large 76cc chambers. Maybe 8:1 CR.
The Eddys should bring your CR to low 9s. More power and a lot crisper throttle.
OK but you could still do better.
CR is your #1 tool for HP for the buck.
I would still look around hard for some 57cc heads. That would give you high 9s.
Another excellent choice is AFR heads. They might be 64cc but they flow better than anything else (HP)
Make sure you check Summit, they are the single largest stocking distributor for this stuff.
FT Cams:
For low 9 CR the old school Comp 268H was dead near perfect. It built as much cyl pressure as possible.
It has 218* dur @ .050" that's a good upper limit before the lower rpm cyl psi starts to die off.
And this old school cam has 50* hydraulic intensity (spread between advertised and .050) which lives much better & easier than the fast-ramp XE cam that was mentioned..
I do not like fast ramp flat tappet cams. They have high lobe failure rates. Leave that trick for the rollers.
One way to almost guarantee the lobes will live is to use Jebbysans detailed break-in procedure.
Another is to use Howard Cams Guaranteed warranteed not to fail combos.
They are the only co in the industry to do this, and they choose 50+* ramp cams (surprise) and Comp has had some issues with their XE cams and other cams. Their 213* dur cam has 54* ramps and is close to the Comp 268H, but warranteed against failure.
If you want a tiny bit more cam/HP they have one in their regular listings.
The 215* Street Force 2 fits the bill. And should build low end cyl pressure, and come on strong right off idle, 1200rpm up.
Done and I bet you can "afford" the AFR heads, and stay under budget, and make more HP.
Last edited by leigh1322; Aug 18, 2024 at 03:25 PM.
In defense of Comp Cams I have been running the Extreme Energy flat tappet for several yrs without any issues whatsoever except for one:
I pulled the lifters back in July for an inspection. One lifter refused bleed off due to debris inside. clack-clack-clack.
My fault, I let shop towel fragments get in the oil orifice during a Intake upgrade.
My fault. No fault on behalf of Comp Cams.
I was amazed at every single lifters base and cam lobe. Looked like new, zero signs of wear.
I will encourage use of Comps XE cams any day.
That is about what I paid for my heads, fully loaded a few yrs back.
In case you haven't noticed, price for just about everything skyrocketed in the last four years. So yeah, what ever you paid for anything "a few years back" is pretty much irrelevant today.
In case you haven't noticed, price for just about everything skyrocketed in the last four years. So yeah, what ever you paid for anything "a few years back" is pretty much irrelevant today.
After porting, I bought the valves,shims seals,guides and springs and it with $100 machine work to recut the exhaust valves to better work with my valves it was still about $700 total cost... YMMV and I know AFR uses 8mm valve stems and does their own likely better valve job so its up to the consumer to determine if thats worth the cost. I think even for $1200 they are a good value. I seem to remember they were about $1200 a pair 4 years back when I looked also but I could be wrong.
I dont disagree that a lot of things have gone up dramatically in cost but not everything.
The AFR heads are worth a small premium over others, if you can handle the cost as-landed.
As mentioned before the guy that stocks & imports heads in your country will likely have a $ advantage.
Talk to him, maybe he can do the AFRs also.
What ever heads you buy, match the springs to the cam.
Those are HR springs and slightly stiffer than you would need for a flat tappet.
You want as light a spring as you can get with a flat to increase your likellihood of no lobe failure.
Those are PAC springs which are very very good ones.
Trick Flow sells a 56cc cyl head, it uses 1.94" and 1.50" valves which would not be a detriment to your cause. The intake runners are 175cc and are perfect for a 350 with a small cam. I would use a single pattern cam such as an Isky 264 MegaCam or the bigger Comp 268HE. $.02
The 57cc Trick Flow heads gets your CR into the mid-high 9s.
The valves are big enough for ~300-340ish HP.
The intake ports are perfect for a 330HP 350.
Both the CR and the high port velocity of the 175s will make your throttle much crisper.
The AFR might flow a tad better, but the CR increase may well likely be worth the trade-off.
The AFR heads are worth a small premium over others, if you can handle the cost as-landed.
As mentioned before the guy that stocks & imports heads in your country will likely have a $ advantage.
Talk to him, maybe he can do the AFRs also.
What ever heads you buy, match the springs to the cam.
Those are HR springs and slightly stiffer than you would need for a flat tappet.
You want as light a spring as you can get with a flat to increase your likellihood of no lobe failure.
Those are PAC springs which are very very good ones.
It should be pointed out that the AFR enforcers mentioned in this thread are likely available under other brand names in Europe and direct from china as they are not actually AFR castings like AFR's other heads. With the Enforcer line the castings used are a chinese knock off of the dart pro one head design that AFR just recuts the valve seats and installs 8mm guides in and sells as their budget line.
They are the same chinese heads a half a dozen other people have also been selling as other brands of heads and Eric Weingartner has done a number of you tube videos on these showing they are a pretty good value. These are also the same heads skip white sold as the NKB heads until they started just reselling the enforcers themselves.
If he runs the AFR heads with a thin head gasket, would that put him closer to achieving his goal as well?
Both heads sound like he will be in the ball park.
