Custom ground camshaft, low power

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I just read a bunch of info on solid lifter cams and think I might be up for it. The xs282s thats been mentioned says its rpm range is 2500 - 6500. Right now I make peak power at 5500 and have a rev limiter set at 6000. Would I be safe reving my motor to 6500?
Another question. Why do almost all calamity have more lift/duration on the exhulaust side? Isn't the intake more important. Id think it would need to be the same or bigger on the intake. Id like to get as much lift as I can fit. Particularly on the intake.
 
They (should) design the cams for the heads, compression, exhaust, intake, vehicle weight, gears and trans type.
If you contact Clay Smith they will want all of that info to give you the best cam for your set-up.
Generally speaking, upping the lift and/or duration on the exhaust side helps the heads flow better because the exhaust side is generally lacking.
Ideally, as a rule of thumb, you want a intake/exhaust flow ratio of 100/75 on your head flow.
Most heads do not achieve this so they cheat it with the cam profile.
This is where split lift/split duration cams came from.
 
I didn't address your first question...revving to 6500...I'd say yes. The question is, do you need to?
 
mopar340dave said:
They (should) design the cams for the heads, compression, exhaust, intake, vehicle weight, gears and trans type.
If you contact Clay Smith they will want all of that info to give you the best cam for your set-up.
Generally speaking, upping the lift and/or duration on the exhaust side helps the heads flow better because the exhaust side is generally lacking.
Ideally, as a rule of thumb, you want a intake/exhaust flow ratio of 100/75 on your head flow.
Most heads do not achieve this so they cheat it with the cam profile.
This is where split lift/split duration cams came from.
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I'll contact clay smith this week and see what his recomendations are. I'm going to try and get my vehicle weighed this week. I'll probably wait till then to talk to him.
 
805moparkid said:
the piston needs to be at TDC or a valve could be open... (probably not at half way though lol)
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its a good thing you didn't read my post and do your leak down test correctly so you have accurate numbers to work with...
 
sbh126 said:
I'll contact clay smith this week and see what his recomendations are. I'm going to try and get my vehicle weighed this week. I'll probably wait till then to talk to him.
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I'm not convinced the Erson cam you have in the engine is the problem,but if you want to swap cams call Tim @ Bullet cams if you want an upgrade.
 
Forget the chassis dyno numbers. The numbers will vary a lot from dyno to dyno. Even how tightly the car is cinched down will have an effect. The dyno is for tuning and testing parts, not for telling you exactly how fast your car will be. Take the car to the track and see how it runs. There is more than one 11 second car out there that makes "only 310 hp" at the rear wheels. I would say your biggest component issue is those damned puny headers, not the cam.
 
Looks like I lied about header size. I went and measured the circumference of my pipes and the outer diameter is 2.14" So I'm guessing I have 2" pipes. I'm not sure why I was thinking I had 1 5/8 pipes. I have Pro Parts headers that I bought through schumachers. Are these healthy enough for the numbers I'm looking to get?

I did another leakdown test. I didn't calibrate it correctly the first time. I had 20% leakdown on a cold engine. I was told not to pull plugs out of hot aluminum heads or I'd do the test hot. Is there any truth to this? According to the gauge I can have up to 40% leakage and still be in the mild range. 40-60% being moderate, and beyond that extreame. So I should be safe.
 
I emailed clay smith, hughes, and about 5 other cam companies the same email with all my specs asking for recomendations. I'm interested to see the differences in opinions. I'll post again when I get some replies.
 
When the plugs are installed, you should be using a dab of antiseize onb the threads. Some plugs have some sort of coating now to keep them from pulling threads, but I always use antiseize. You have to do the leakdown test hot. Same thing with any compression or cylinder pressure testing or it is inaccurate. 20% leakdown sucks. With a fresh and healthy engine, at running temp, and standard gapped top rings, should be less than 10%. With gapless, that can drop to less than 2%. Think about it... If you really had 20% (I dont think you do because you did it cold) where you might have 160psi for pressure with than amount of leaking by you might only have 130. That is a big difference, and means the engine will feel lazy. The leakdown tests ring and valve sealing. Compression tests test the pressure peak. The compression test should be done hot, with all the plugs out... It part of the joy of an RB A body...lol.
 
bad news. I had similar results with a hot engine. Right around 20%. I couldn't tell before but when I did the test this time it was at night and alot cooler and I could see quite a bit of steam coming out of the carb when I would put pressure to the cylinder. I had the same results on the #1 and #2 cylinders. I still couldn't really notice anything on the exhaust side. When I pullud the cap on the coolant to look for air bubbles I noticed a few drops of oil in the radiator. I think I'm gunna pull the motor and run through it again and check everything out. Hopefully I just need some head gaskets. I'm going to go ahead and do the test on all cylinders so i know where I'm at before I pull it out. Is it a possability my rings aren't gaped right? What could cause my intake valves to leak but not the exhaust.
 
If you have leaking could be your rings or gaskets arent sealing correctly maybe
 
sbh126 said:
bad news. I had similar results with a hot engine. Right around 20%. I couldn't tell before but when I did the test this time it was at night and alot cooler and I could see quite a bit of steam coming out of the carb when I would put pressure to the cylinder. I had the same results on the #1 and #2 cylinders. I still couldn't really notice anything on the exhaust side. When I pullud the cap on the coolant to look for air bubbles I noticed a few drops of oil in the radiator. I think I'm gunna pull the motor and run through it again and check everything out. Hopefully I just need some head gaskets. I'm going to go ahead and do the test on all cylinders so i know where I'm at before I pull it out. Is it a possability my rings aren't gaped right? What could cause my intake valves to leak but not the exhaust.
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Just a thought but you mentioned you have stealth heads on the engine,did you bolt them on out of the box?,if you did theres probaly light showing between the valve and seat.I have yet to see a set of aluminum heads (anybodys) that does not need a valve job to be correct,I have seen them run but with piss poor results (leakdown/power) such as yours.
 
As for oil in the radiator, does your radiator have an auto trans. cooler built in? I've seen them leak causing that far more than an engine problem. I don't believe leaking head gaskets would put oil in the radiator as there is only the one oil port going up through the block to the rocker arms and it's quite a ways away from any coolant passage.
 
moper said:
Can you list the rest of the engine specs? Who ground the cam? Was it degreed? What kind of power numbers are we talking about?
Larger duration vs actual lift is not a big deal, but other factors amy make any cam not work as intended. If the engine in a place where you can get some cylinder pressure readings? (is it in your car?)
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the part # said high flow i'm betting it's a sig erson cam from the late seventies
 
lead69 said:
Just a thought but you mentioned you have stealth heads on the engine,did you bolt them on out of the box?,if you did theres probaly light showing between the valve and seat.I have yet to see a set of aluminum heads (anybodys) that does not need a valve job to be correct,I have seen them run but with piss poor results (leakdown/power) such as yours.
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I had my machine shop look them over when I recieved them and they said they were good to go. Maybe they didn't look very hard.
 
fishy68 said:
As for oil in the radiator, does your radiator have an auto trans. cooler built in? I've seen them leak causing that far more than an engine problem. I don't believe leaking head gaskets would put oil in the radiator as there is only the one oil port going up through the block to the rocker arms and it's quite a ways away from any coolant passage.
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No trans cooler. Its a 4 speed car. I also have a decent amount of water coming out the exhaust when I first start up.
 
Oil in the radiator isnt a big deal if it's just a sheen of it. Bad amounts of oil in the coolant will cause the coolant to change colors and foam. In a fresh engine or replacend parts I'd expect to see some oil in there. If it's big floating droplets, even that's not a huge deal unless it is an ever increasing amount. Liquid water out of the the exhaust is all condensation unless it's accompanied by steam. Lots of steam. Like can't see the neighbor's house and wont stop steam. Liquid water out the tailpipe when the engine is warming up, or in a car that isnt driven. Not a problem.
 
sbh126 said:
I had my machine shop look them over when I recieved them and they said they were good to go. Maybe they didn't look very hard.
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Do a good leak down test and see if theres any air coming up through the carb.
 
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