I hope so cause I can't wait to see what that car is going to do once it's right. I got a car that I'm finishing that I want to compare something to, much smaller motor.

South Holland

Your probably not 5 miles from there. If you see the Chevelle tell him Skinny said "hello". He's (Andy) a very approachable guy. They're heading to a track in Indiana at the beginning of the month for a little test and tune. The Chevelle is low 12's (with no launch) and should go mid 11's once he get's a decent 60'.

Can't wait to see some big changes from this car and see the owner get the timeslips it was built for. I'm guessing we'll see the first 11 seconed timeslip on page 5.

I can't remeber, did antone cover the fuel system and whether or not it was enough? Pull plugs ? Just fishing? I had a friend go from 11.70's to 12.20's in 1 week by changing to a fuel pump that happened to be clogged with debree.

I had thoughts of bad rings when the car first lost power after about 500 miles on the motor when I was breaking in the motor. Right at that 500 mile mark of babying the motr, I know significant power loss and thought the rings were bad then, but the shop that built my motor said he didn't think so. I took the car to another mechanic friend's of his shop and they all said the motor was good. It seems like I am getting way too much crankcase pressure and it will blow oil out of my front or rear instake seals after I get about 5 or 6k on the rpms. I posted my compression test and was wondering does anyone else think this could also be the problem that was at the beginning. I changed cams, springs and installed new heads, had the carb cleaned and rebuilt and headers and power still seems down. Before I could give it half throttle and spin the tires very easily now itg is now so easy.

I was saying imo that I thought you had a problem with your motor other than those little things. Your compression numbers say you may have a problem with #6 and #8. The oil blowby could be from some cracked rings or bent valves and if so then beating on it at the track just made the problem worse. If the rings were installed too tight then they could have butted which could have caused some to crack. That or blowby from the exhaust valves. At this point it seems that the motor is lossing power and getting worse. Do a leakdown test and that will tell you if it's time to get dirty.

Will be purchasing a leakdown tester this week and see what that says.

In your testing, it would be a good idea to do a wet compression test as well. A few squirts of engine oil into the test cylinder will help provide a better seal on the rings. If the cylinder pressure goes up substantially, then it may indicate that the rings aren't sealing as they should.
There's also the possibibly with a flat tappet cam of a lobe or two going away. ( I speak from experience on that one!)
What engine oil do you use?

I just ripped the motor out and will be taking it back to the shop that built it in Joliet, IL. I am pretty sure that the problem is with the rings. This loss of power on this engine has been a problem since after break-in. It also ran hot during break-in from my fan belt popped off and I think this may have damaged the rings and it was during the 500 mile break-in period, I have changed heads, exhaust, stall converter, cam/lifters and had the carb rebuilt. None of these seemed to solve the engine.

Brad Penn Racing oil. I think that oil replaced the Kendall racing oil. Use that brand for the high amount of zinc for flat tappet cams.

Don't they recommend using high zinc content oil as well as a special lube on the cam before installing it?...Or maybe im making stuff up....

Ouch!

[quote=BadaPwned;4222028]Don't they recommend using high zinc content oil as well as a special lube on the cam before installing it?..QUOTE]

From what I understand the racing oils have a high zinc content.
And I would only hope that the proper break in lube would have been used during assembly as well as the necessary precautions and procedures for flat tappet cam break in.

Yes, the cam comes with a special lube that you use on the cam and lifters for a flat tappet cam setup and then you run the engine at around 2500 rpms for 30 minutes, then drain the oil and change the filter and then add new racing oil. I have never lost a cam lobe this way and have change flat tappet cams alot. You can also use the racing oil along with a bottle of GM EOS, but not neccessary with every oil change, but it does not hurt if you do use the GM EOS with every oil change. Mainly use EOS with the new engine break-in.

So what were the results of the leakdown test that made you pull the engine?

Cylinders 6 and 8 were down to 60 percent and pressure going out to the crankcase.

Well since you are pulling the motor out, NOW would be a good time to change to a solid roller cam. That way you don't have to think about zinc and other things that is needed for a flat tappet cam. There are plenty of great off the shelf cams that will give you much more hp and trq with way better low end than what you have with that flat cam. I hope they get down to the bottom of your motor problems soon. If not you can bring it to me and I'll get you straight. Lol

Big Dog, What cam do you recommend or should I just call a cam manufacturer and see what they recommend?

Excellent info.

mcbchild, i would suggest calling the camshaft manufacturer for the camshaft selection. give somebody like bullet racing cams a call...there's a handful of people on this board running their camshafts all with ABOVE AVERAGE results...

Thanks for you guys help. I'll keep you all posted when I get my engine back and installed.

Changing to a solid roller is a few hundread dollar upgrade. Your car is capable of ten second timeslips with the cam your running. And if you broke it in properly which is sounds like you did, you shouldn't have a problem wiping lobes. Also if you change the profile of your cam to something with a longer duration your going to require a higher stall 8 inch race converter which will set you back $800.00+.

Well you could go with a custom grind or save a few bucks and get a good off the shelf grind set up for about $450-$500 from Competion Products. I ran some different grinds on your motor combo on the laptop and the Comp Cams 12-771-8 did very well overall. Made more hp and torque will have a much better idle and WAY more torque down low (works well with current TC). The car should be 4 to 5 tenths quicker than with your currrent cam and will last without having to add baby oil or worry about pulling the motor again cause you took out a lobe. IMO

Brodix says their Track 1 heads like to operate in the 3500-7000 rpm range on 350 to 400 cubes. Where does that take you in your cam selection?
They still keep flowing up to .700" inch lift so you have a pretty big cam to consider.
They also recommend 11.5:1 SCR to suit the large profile. If I remember you have almost a full point to make up.

With the comp cam I was talking about he should have .600+ lift with the 1.6 rockers. As far as the flow of the heads he could put a big A** cam in but then he'll have to start buying of stuff to make the combo work. If it was me I would change that cam out after he gets the motor fixed then put it back in the car, dyno tune it then dial it in at the track before the season is over. With THAT combo that car Should run 10.6-10.8s once it's dialed in and be good on street. IMO

Well if the cam I have will put me in the 10s or very close, then I will not be changing out my cam. I will continue to use the same cam since it is already broken in. As far as compression goes, I will just use a thinner head gasket and that should get me close to the 11.5:1 compression needed for these heads.

That cam you have should be good for 125 mph! Keep it

I don't suppose you had the chance to measure the cam ICL before you handed it over to the machine shop (or ask them to double check it). It would have been an interesting bit of information to have.
As far as cams go, obviously if the cam you have will help you achieve your goal ( and the price is right )then it makes sense to use it.
The suggestions on the other cams are all very good. You always have the option of an upgrade later. It wasn't until I wiped out my flat tappet cam (I didn't have the info then that I do now about oils and supplements) that I went to the hydraulic roller. Certainly never regretted it and the more aggresive profile (not that it's very big) made a huge difference in performance.

Just curious what the SCR has to do with the "larger profile"??. As a normal engine would have higher perf. with increased compression naturally, are you stating he will gain up and beyond the natural increase just because they are a "larger profile" Brodix head??

Or are you saying up the SCR because they suggest it? Kind of like AutoCAD suggests a 750 gig HD even though you don't need it? lol...

Hopefully this made sense....

Big cams need more static compression to help build cylinder pressure. That's where dynamic compression ratio comes into play.
Brodix makes those heads to flow a lot of cfm at some very large lift values (up to .700" in their charts.) That typically means a cam with longer duration as well. If the static ratio isn't increased to suit the "larger profile" then you're leaving horsepower on the table. Cylinder pressure will be low and torque production will be down. That means reduced power across the board.
Like the 750 gig hard drive, you don't have to a huge cam however if you're going to get the MOST out those heads that's what's recommended.

I will ask him to check the ICL and post it here probably by next week. Also, I will stick with the cam I have now and once I get everything running correctly with the setup I have, I will think about upgrading internals later. Right now I don't have the full 11.5:1 compression recommended for the heads anyway, but with the thinner hg gaskets I'll install when I get the shortblock back should get me close to that goal and bring up my DCR.

Ahhhh, Its relative to the cam profile. Makes sense. Now, say he had a roller cam, would their still be an issue? The cam would be much more aggressive possibly reducing valve overlap....or maybe I just made that up lol

One of the advantages of a roller is being able to achieve higher lift numbers without having too much duration (and overlap as you suggest) for the rest of the combo.

So basically, for the cost of a roller setup is not really worth it for me just to gain 2 or 4 tenths?

Lol, I would ask yourself that question. Do you have money burning a hole in your pocket? If so, then I would say do it now while the motor is apart. Or, use what you have and be happy you saved a few hundred dollars. You never know what may happen, your fridge could be on its last leg lol...(Ill stop, its getting off topic lol)

$1,000 for 4 tenths would make me a happy person!! but i doubt you would pick up that much just from flat tappet to roller. however you should pick up much more than 4 tenths just by making your car run right. i still would have liked to seen a chassis dyno sheet when the car wasnt right.... but maybe when you get it back in the car everything will fall into place.

The roller could worth a lot more than a few tenths. It would depend on the cam.
Remember, you have great cylinder heads with lots of potential.
However if you were to compare apples to apples, a roller with similar duration numbers as your current flat tappet may give just the 2 to 4 tenths you're talking about.
As was suggested, you may get that (2 to 4 tenths) out of your current cam once it's been degreed correctly and you bring the SCR in line to what's needed (if it's not already).
We're all car guys (or girls). Swapping in a new roller is an afternoon spent in the garage if and when the time comes.

To do a roller setup dsn't cost $1,000 don't believe the hype. You can get a custom cam cut for $250 the lifters for $200 and if the springs are not up to par, some new springs. Done it. I'll be suprised if he gets that car to run high tens with his current setup even with a fixed motor, I bet you he ends up buying more or doing more to do it. Low 11s yes but tens he 's going to need well over 440 rwhp to do it and he has to get off that line, we'll see. And yes you can pick up 4 tenths and more going from a flat tappet to roller cam seen it many times. You have less limitations with a roller profile than with a flat tappet profile which allows you to build way more cylinder pressure and keep the valves open longer so more air/fuel can enter the cylinder. Better idle more AVERAGE and peak hp/trq no need for a 4000 plus TC and 4.10s to get off the line which slips more on the top end. Faster more efficient car lower et higher mph. IMO

I must say all the stuff you have posted regarding roller against flat tappett is dead on accurate.

But this stuff above is just discouraging. I made 373 RWHP and only 355 RWTQ. My car will run 124 MPH all day long in heat and went 125 mph frying 1st gear as well.

I will put my info in my signature but if his car runs to potential than there's no reason it shouldn't run a 123 mph in the 1/4. Forget the E.T. His weight and combination has been 10 second power since post #1.
As I stated before he will need more converter and a good tire as do I to run an actual 10.XX.

The heads came with solid roller cam springs and just had the shop remove the inner springs and verify that the pressure now will work with a flat tappet and the springs open is around 475 lbs and closed I believe it was at 150 lbs. I also will be using a 150 hp shot of NOS once the car is dialed in corectly, so 10s should be within reach. At least I hope so.

Well duh (lol) 10s should be easy with spray. You could just add more spray till you get there. And FastLs1 what is your race weight. Your combo with THAT cam is more balanced than mcbchilds motor/cam combo. Don't get me wrong guys his car is going to FLY but I'm a lil greedy when it comes to this stuff because I race for money. So if I can do something that will make me faster or knock off 5 tenths then I'm going to do it. It's no fun losing a couple hundred $$$ buy a half of fender cause you picked the wrong part. Been there lol.

I just thougth I would post up my combo and times. You should be beating my time by quite a bit. I hope you get it figured out.

I would swap over to roller if I were you also.

Good luck, My times an combo is in my sig. Thats at 3400 lbs with me an 1/2 tank of gas.

oh yeah, mine is a stock bore/pistons/rods L98.

I'm not sure what my weight is. But it is a full car with glass hood and welds. It has full interior with PW,PL,PS,PM, and full dual exhaust and tubular T/A with Cross member.
My guess is 3350 with 1/2 tank of gas and myself. I weigh 168.

Fast, good times but @ 124 mph you are making more than 375rwhp and 355 rwtrq lol you know that. That dyno must have been on strike that day.lol!

nice... whats your 1/8 mph?
my LS1 car went 92-93ish when it made 376 rwhp. full weight 6 speed car. i guess probably around 3500 or something with me in it.

Several of the on-line horsepower calculators say that 3350lb vehicle needs 500hp to go 11 flat at 124mph. Take 20% away for the drivetrain and you're not too far off 400rwhp.

Yeah true, but after you factor in wind, temp, humid, and traction the hp needed goes up. But that shouldn't be a problem cause he has the juice

Hey Mcbchild did you get that motor straighten out yet? What did you find out? Let us know.

Will getting the motor back from the shop tomorrow. Nothing was found to be bad in the short block itself. He thinks maybe the piston rings lost tension and discovered that one of the pistons had a burn mark on the side of the piston like something got hot or detonation, but piston is not damaged. He is also decking the block since he thinks even with my heads milled down to 63cc and I have 11 to 1 pistons, that I am only getting around 9.7 to 1 compression and the decking will bring my compression back up closer to 11 to 1.