I was just wondering what would be a good cam choice for the fiero 3.4 swap.I was wanting something somewhat aggressive with a nice rumble to it yet retain the lifters,etc,of the 3.4....thanks again for alll the helpful advice
You need to install new lifters with a new cam. Regardless of what it is.
With that said, I believe the Crane H260 (.427/.454, I/E lift) is about the biggest thing you'll be able to install without any machine work on the heads. Still probably need to replace the springs. I would also get the Comp 1.52 roller-tip rockers, too. They're not terribly expensive, are more precise than the stockers, and will save on valve stem wear.
------------------ Raydar 88 Formula IMSA Fastback. 4.9, NVG T550 Praise the Lowered!
Yeah, the Fiero uses flat-tappet lifters. They must be replaced when you replace the camshaft. But most new camshafts will come with a set of new lifters.
As for which camshaft to use, you'll get varying opinions on that. The Edelbrock and the Crane H260 are both similar, but the Edelbrock is less expensive. You'll get a mild performance increase (better mid-range torque), and a slightly more aggressive sound. The Crane H272 will give you a bigger performance boost and a more aggressive sound, but will require aftermarket valve springs and possibly some head work.
IMO, if you're going to keep stock Fiero intake and exhaust, then go with a milder camshaft. Because it'll be a waste to have a high-performance cam with the stock manifolds. On the other hand, if you're using headers and a better flowing intake, then the higher performance camshaft would make more sense. At least, that's my opinion.
Basically agree with Blacktree but to elaborate on his last point; realize that a free breathing cam on a 3.4L using the restrictive 2.8L intake can only to go so far. At the very least port the intake and exhaust system. Another way to overcome the breathing limitations is to bolt on a turbo. Pressurized compressed air greatly increases its volume and therefore overcomes much of the shortcomings of the Fiero intake system. If you go turbo then its advisable to use a turbo cam and keep the compression at 8.5:1. First decide how much power you wish to make then plan accordingly.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
i used the edelbrock cam/lifters with stock heads on my 3.4 camaro engine I swaped into a isuzu trooper. I can tell you it was a good upgrade. but.... like others have said the intake is the weak link. on the isuzu i was using a tbi intake that I ported the crap out of.
Originally posted by Blacktree: ... IMO, if you're going to keep stock Fiero intake and exhaust, then go with a milder camshaft. Because it'll be a waste to have a high-performance cam with the stock manifolds. On the other hand, if you're using headers and a better flowing intake, then the higher performance camshaft would make more sense. At least, that's my opinion.
I agree with this as well. The stock intake manifold will choke the 3.4 at ~5000 RPM. Any porting that you do will be worthwhile. Check out the cut/weld job that "dawg" did on his intake. You need to at least do something similar, and go with a larger throttle body. If you're going for maximum power with the 3.4, port the heads and lower intake as well. Headers will be useful. If you're going to the expense of porting the heads, have the valve spring pockets machined for spring clearance, and install a Crane H272 (or similar) cam. (I did "all of the above" with my 3.4. It ran like a striped ape, but it was sure expensive to do. I had over $800, just in the heads. Unless you are after a stock look, there are probably better "bang for the buck" options.)
[This message has been edited by Raydar (edited 08-18-2015).]
for starters,i didint ask for a smartass response,secondly i am a d d,so if you have nothing else better to do,i suggest you keep your thought to yourself and third,im learning
Delta makes a good 260 equivalent cam. going higher to a 272 will give you more of the loping sound but have to be careful about clearance and likely would need a machine shop to help you. 260 there is no worries. If you have spare change there are a number of things you can do to give it a bit more umph. do a search for Dawg's intake modification. porting the exhaust headers, bigger TB from Steve Monroe. it does start to add up depending how much you can do yourself. just keep re-reading what you find. it makes more sense once the motor is sitting on the garage floor.
If you're just looking for a mild improvement over stock and a slightly more aggressive sound, you could keep the stock cam and get a set of 1.6:1 rocker arms. Then you won't need to mess with the cam, lifters, or valve springs. The stock camshaft with 1.6:1 rocker arms will be roughly equivalent to the Crane H260 camshaft with stock rockers. The Comp Cams 1.6:1 roller-tip rockers cost about $130 for a set.
Also, most replacement cams for this engine use hydraulic flat-tappet lifters. I would suggest sticking with that, unless you're building a racing engine. Because a roller valvetrain can get pretty pricey. In addition to a roller cam and lifters, you'll also need custom-length pushrods. Oh, and don't forget the full-roller rocker arms. Of course, the full-roller rockers will require special rocker studs. And you may need spacers under the valve covers to clear the full-roller rocker arms.
[This message has been edited by Blacktree (edited 08-28-2015).]
