I got a gr8 deal on a xr288 cam for my 383 build, i didnt realize it had quite a bad rep? (https://www.thirdgen.org/forums/tech...oller-cam.html)

Im speccing a 383 build, i have a vortec roller block, 383 kit (eagle or scat), alu 200cc heads with 1.6/2.02 valves, aiming for about 10-10.5 static, tight squish, 373 rears in a 28" rear tire and 2004r.. just want a brutish street machine to push hard for short bursts on the empty backroads round here- this is in a 77 camaro..

I will prob get a 4 degree adv retard crank timing set to check where the cam is when assembled..

Any thoughts on this cam choice? I can always return it-

Edit:
I couldnt care less for how my car "lopes" at idle! I want bada$$ power!!

also - what tiing "could" work for this? 12-18 initial, 10 in the can, 32 max? ive always run around 12 initial and about 32 max but heard having more initial and light light springs will make a big difference? is the 20-22 initial including the 10 in the can?

 

That post is about the Thumpr cams, not the regular XR series. The XR288 wouldn't be too bad in a 383.

Ideal ignition timing will depend somewhat on the heads and your choice of fuel; but I'd guess, 16 -18° "static", 35 - 36° "total", plus 12 - 15° of vac adv, would be a good ballpark for going with that cam with pump premium.

Good luck getting that cam through smog check.

 

ok thanks, any idea why the cam isnt too bad? I followed it from the Ryan's combos specs and it showed 500/500 or there abouts.. I was thinking of experimenting with a 2 or 4 degree advance as well as single vs dual intake to see what runs nice..

 

I don't know about "bada$$" power. You'll make about 350 at the rear wheels - which on that chassis which is heavier than a third gen by a good bit, it will certainly be fun - it will get sideways. But I wouldn't call it terrifying.

GD

 

thanks - yes was just wondering if the cam was far out of spec or not-

 

Not quite sure how to answer that.

Or this either.

I've never run that particular cam, but I did run its next smaller brother, the XR282HR, in a 400, that just happened to be in my car (83 L69 Z28) when I moved to So Cal from another state. So I've kinda been down that road. I also had A BUNCH of 2nd Gen Camaros like yours, which were basically lead sleds, and had no traction. In fact I traded in a 79 Z28 4-spd to buy my 83.

While your car isn't a 3rd gen Camaro/Firebird (82 - 92) I'm doing you the courtesy of answering you anyway. Yours is heavier than a 3rd gen, meaning, "too much cam" will result in an even soggier bottom end in your car, than an otherwise equal setup in one of these. You don't really have enough compression for that much cam, in terms of optimum power output; and not really enough gear, unless you put in at least about a 3500 RPM converter. After all there's AHELLUVALOT MORE to making a car fast than just quoting some big HP number from somewhere.

An engine build needs a consistent, somewhat detailed, disciplined, orderly design method to succeed by any factor other than just pure dumb luck. Personally, I'm not seeing luck on your side, in this case. You're in CA, with a car that has to be smogged, and there's NO WAY IN HELL that what you're proposing will make that grade. You've got too much cam for a street car with the supporting mods you claim, and don't even know (or tell us, anyway) what heads are involved. I'm seeing a train wreck coming, and not because the XR288 is "bad" or "out of spec"; just, it's not the one you need for the situation you're REALLY in, that is, the world you're in when you're awake.

The 79 Z28 I traded in, BTW, still had its 350 in it; but by that time had 186 heads and 4.10 gears. Might have had some other goodies too but it's been ... over 35 yrs now, memory fades. I can't recall for sure but I think it had a Comp HE268 in it at that time. (not in CA). One of the reasons I traded it in was because that block had The Lifter Bore Problem, wherein the lifter bores don't point at the cam properly, and it EATS lifters and cam lobes. I think it went through 2 or 3 different cams in it over the 3 or 4 years that I had it The L69 305 83 car I bought would RUN CIRCLES around it in bone-stock trim. Not least because in spite of how bad the 3rd gens wheel-hop, it got better traction. It handled better, looked better, weighed less, was ALTOGETHER NICER inside, the air blew colder, it used about 40% less gas, ... I'm not going back to a 2nd gen.

 

Oh and I shouldn't forget that silly "string wrapped" steering wheel in those cars, that BREAKS YOUR THUMBS OFF. My late little bro had one of those in an old Chevelle with no power steering back in the late 70s for some reason, and it DID IN FACT break his thumb. These cars, that we here on this forum own, are just altogether BETTER cars. Why, I can even hit the highway in my 83, and the seat doesn't even make my wallet make my right leg go to sleep within 40 miles or so.

 

if the heads were worth while, it will make much more than 350 on a good 383. I’ve seen guys well over 400 whp with it. However 2.02 valved 200cc alum heads listed sound like some budget castings with mediocre flow profile. Probably right, mid 300’s may be more realistic.

i like the cam, it works well for a shelf grind. I’d like 11:1 comp and a better quality head that flows 280-300 like a afr 195, 210 or profiler 195-210, etc

 

thanks for the replies chaps - well i currently have a pretty darn fast and amazingly fast 350 in the car, blew my buddies 383 out of the water (ok it was really a dog ride anyway). My car is surprisingly comfy to drive, 3 cross country trips in it -

I still have the innards of the 350 i removed last month. This 383 is just something ive wanted to do for a while- The heads im experimenting with are chinese alu 1.6/2.02 ebay cheapos - 250 cfm intake flow and 190 exh iirc- they actually look pretty decent, maybe some light cleanup and basic port matching- ill be running about 10.5 static, and the vic jr intake.. I have about 3-4 vac sec holleys in the garage in various states, and just ordered a brawler 850 mec secondary for kicks to see how it works on the motor..

Im busy looking at 383 kits to order and probably get going on the build in 2 weeks or so.. I have elgin valves on the way and will make sure the valvetrain geometry is tight - 40 squish bla bla.

I havent really done 383/single plane build so this is a little bit new territory - but my 350 build came out real real fast imo- everyone i take a ride in loves the power.. but thats kinda irrelevant to this thread-