I know a lot of you guys are running are used to run a Super Ram on your cars. SO I am hoping I can get some help here.

I've got an 89 Camaro with a 406 using a Super Ram intake. I had previously been running Dart Iron Eagle 200s with hooker long tubes.

I first used a cam with 224/228 duration. Car ran great, but of course wasn't enough. SO I swapped in the LPE219. When I did this I dropped about 15 in HP and 10 in TQ. I was running close to 12.1:1 compression ratio with both combos listed above.

That was fine for a while but then I started seeing some of you guys running the TPIS 700-701 I think it is, which ever one that has the 242/242 solid roller and were getting good results. Soooo, I called up my cam manufactuer and told them what I was looking at but wanted to stay hydraulic roller. So they hooked me up with a 240/246 duration and 540/550 lift (1.5rr) LSA112. Along with the new cam, I went ahead and went with a set of AFR 195s and SLP 1.75 (to gain back my ground clearance).

Now that everything is back together, I am about to dump a can of gas on it and light it up!

My problem is that I have to advance the timing at idle to about 25-30 degreeas advance to get ti to run. When that happens it runs good only on the revs, horrible on the decel and will never idle on its own.

So I talked to the guys where I got the cam from and now they are telling me that I have to much duration for my compression ratio is now about 11.5:1. Needless to say I am not happy with them at this moment. So I called up Comp to get some ideas and one guy says yewah I got to much duration and another says no I don't that I should be fine. Grrrr! I am no expert at this and I am just following what these manufactures recommend.

I had the car looked at by a shop that deals with my ECM, A Haltech E6GM. The shop went through and checked eveything with the Haltecha nd made sure that my igntion was working correctly. They say it was and they have told me that I need to go and look for something in the valve train.

I have degreed the cam the best I could and came up with the correct LSA, but thats as far as I had gotten. Sort of difficult with a hydraulic lifter in place. To me even if the cam was off slightly the advance of 25-30 degreea at idle should not be the casue.

Right now the only thing I can think off is the distributor....... and rotor phasing. I have heard about this but honestly do not know alot about it. IF the rotor is "out of phase" how does that happen and how can I get it back "in pahase"???

Thanks for reading and suggestions or thoughts.

Craig

 

Craig, I've got a friend with a 406 Super Ram Corvette I helped build the motor with. We had a Comp Cam 236/242 HR 112LSA, the comp was about 10.04:1. The car ran 12.00's first time out at 112mph. At the dyno it made 350rwhp and 500ftlbs of torque, I found it to be about 50HP down from what I thought it should be and decided to do a cranking compression test. I found that the engne had 140psi on all cylinders, very low for a strong street performance engine, should have 180-200psi. I told my friend he either had too much cam or not enough compression! I ordered a 219cam for him and while he took the old cam out, I told him to pull the heads off to double check on actual compression. His piston was .017" in the hole, he had a .055" thick stock type Fel-Pro gasket (1044?) and his AFR 190cc heads had a 70cc chamber, so his actual compression was 10.04:1 and with a intake closing point of about 63deg's his actual running comp was 7.5:1 too low. I got him a Cometic .027" gasket, along with the 219 cam,(which has a intake closing point of about 52deg's) this will bring up the comp to 10.7:1 and the running compression about 8.4:1. This should wake this motor up drastically (low-end/mid range) I expect at least a 50HP gain. The engine is being put back togehter and I 'll keep you posted once it's done. I'm not sure if this is your problem but it's something to keep in mind. Check your cranking compression, check your intake closing point and then check your running(dynamic) compression,should be about 8:1, this will tell you if your cam/comp choice are adequate. Super Ram intakes don't like big duration, I believe the best cam for this intake is the 219 and I'm sure lot's of people here on the forum would agree. The bigger 242/242 roller is really not that big when you consider it's a solid roller. By the time you equate the lash and the fact that rollers (solid) make more low end than their equal duration hydraulic counterparts the 242 will almost be equivalent to the 219! Check that Dynamic compression and of course don't overlook the basics! Good Luck! Juan. Hope I've been of some help?

 

Forget that rotor phasing stuff. If your engine will start and run there's nothing wrong with the "phasing". Yours is a TUNING problem.

I'll assume you don't have a vacuum leak and that all the sensors are working properly, TPS set, IAC working as it should, etc.,

You didn't mention what idle rpm is burned in the PROM. With the cam you're now running you'll need at least 900 RPMS, closed loop, idle, in gear (if you have an auto trans).

The timing you're reporting is partly based on the rpm it's measured at; I'd need that number. You posted 25-30, but at what RPM?

Most modified engines idling at 800/850 are running at 22/24 degrees of advance with the EST plugged in.

You are going to need a PROM re-burn to account for the longer duration cam in the engine now. Your PROM's fuel and timing maps will need to be changed. Not only are you now running a lot more duration, but you've also increased the overlap a lot.

Don't expect the engine to run anywhere near the same, down low, as the 219 or the 224; you've jumped about 4 cam sizes bigger. Higher compression ratio can bump up the low end to get back some of what you lose with the longer duration cam, but with the engine together and running, that doesn't seem like an option now.

Your power brakes are going to be marginal and MAY need a vaccum can to work reliably. You'll come to a traffic light and stop behind another car with no problem. Light turns green and the lead car pulls off but suddenly stops (for whatever reason) you try to stop and can't and rearend him. Why,? Not enough vacuum to refill the booster after the initial stop.

In the meantime all you can do is bump your initial timing to 10 degrees to try to get the engine to idle and adjust the Throttle Body minimum air flow screw to raise the airflow through the TB at idle.

Jake

 

Hey thanks for the replies. There's some stuff there I would never of thought of.

The one thing the bothers me the most is that the car will run. Yeah it takes a lot of advance but it ran, and once it did it was about 1100 RPMs. The engine would cough alot and sound like its starting but once it caught I had to be on the throttle to keep it running. That border line of running or stopping was 1100 RPMs give or take a 100. The vac was pretty good I thought. I had 12 inches at 1200.

In my ECM program (there is no PROM to burn) I had the target idle set to 850 at first but then when I was starting to have these problems I had set for 1200 to see if that would help. Made no difference.

All sensors do work and I did come across one vac leak in the break booster line coming off from the manifold but that was obviously replaced.

The intial timing is what I am trying to set and what I am having to advance so far to get the motor to run.

It's no big deal right now. I have the cam out and trying to decide what to put back in there other than the LPE219. I know it's a great cam but I had better results (track wise) with something that had a little more duration and less lift.

 

But you had better track results because? It sounds like you're throwing parts together and then hammering it without tuning or paying attention to fuel delivery. As it's been stated, the longer duration will really hurt your drivability and the 219 might have performed less than ideally because of tuning issues (or the lack of tuning).

You may want to try to dial in the 219 and see where you're at first, especially if this is a daily driver.

 

OOO, no, no, I have had both combos tuned and dyno by the same tuner.

 

If you've got the cam out, i'd recommend finding something in between the 219 and the monster cam you have. I had the SR on my 406 with a big cam (TPIS 701, but mine is actually 246/246) and while it wasn't as bad as yours, the idle was very weak. Here are a few things that helped. You may have to open you TB a little more. I closed my IAC and opened the TB til it would idle around 900 on it's own. Having 20-30 deg of timing with the ESC plugged in is about right. If i unplugged my ESC, i would have to open the TB even more to keep it running. I also had a problem when it went into closed loop...it would surge up and down until it stalled. I found a small vacuum leak and installed a heated O2 and one of those solved the surge problem. It idled well at 900, but still very weak in that if i blipped the throttle it would sometimes stall or start surging again. And if the idle dropped below about 800, it would just stall. It was drivable tho and ran strong at the track. In fact it had too much low end torque, and i switched to a single plane intake. Oddly enough, the SP, while more choppy, will idle down to about 400 rpms and not stall....a much stronger idle.

however, like i said, if you have the cam out, get something smaller. With 10.5:1, i'd shoot for something in the 225-230 range with as much lift as i could find on a 112 lsa or just stay with the 219. Good luck

 

I had a distributer that was out of phase. When the timing was advanced beyond a certain point the spark would jump to the next terminal. With a timing light hooked up you could see the timing change jump a huge amout at that point. To check the phase I drilled a 1 inch hole in an old cap between the #1 terminal and coil, painted a white line on the rotor. You can see where the rotor is pointing while firing using the timing light.

 

I cant add much cause I wont put my 406/SR on the road till Saturday .

But, my cam grinder said that an equivelant to the TPIS 701 cam (242/242) would be 233/233 which is what I bought. I guess some have a 246/246 too.

Mine has idled nice from the get-go, no issues.

I have 10.97:1 CR with AFR 210's.

 

In dealing with these kinds of problems, one has to make certain basic assumptions, like the engine is screwed together correctly and none of the settings is DRASTICALLY away from what's generally accepted to be the norm.

Sure, it's POSSIBLE, but who would ever think that someone would be dialing in so much initial base timing to cause that to happen!? If base timing is set anywhere near the stock recommended setting, (from about 12 degrees BTDC on down to 6) phasing isn't any issue.

Of course, if you are trying to dial in 20 degrees of base, who knows what would happen, other than the engine being very hard to start: Groan, pause, Groan, pause, Groan then maybe catch and fire.

In the BB race engines I use to build, the timing was locked in, 38/40 degrees fron start up to redline. So we had to have a separate starter button and a separate ignition switch. Push the starter button and hold it until the engine is spinning over freey and oil pressure rises, then flip the ignition switch which fires the engine.

Jake

 

sorry to get off topic, but quick question:

Larry, how did you match up the base to the 210s?

 

OlRJ, (master welder) welded more material onto the runner areas, you can't even tell it was done! The 1206 Felpro fit very nicely!

 

You have, and everyone else who responded. Thank you very much.

Can you explain this a little better about the 242 solid almost requating to the LPE219?

Thanks again,

Craig

 

A solid lifter cam is generally considered to be one step smaller than a hydraulic cam of the same duration spec, in the way it actually performs in the engine.

A step is generally considered to be 6 degress in duration.

So if you subscribe to that rule of thumb, a 224/230 hydraulic roller cam is about equal to a 230/236 mechanical roller.

Looking at it another way, if both cams have the same duration, say 224/230, the solid cam will perform like a 218/224 hydraulic once it's up and running in the engine.

Generally speaking.

Jake

 

And the reason for this is because a hyd cam has zero lash. so as soon as the lifter starts to rise, the valve opens. With a solid, the lash has to be made up before the valve starts to open.

 

Thanks, that explains a lot and something I never knew. Cam I got now is totaly wrong for sure.

Thanks again!!