When checking the throttle opening, you simply check visually that the blades are open fully and look at the tps in the software. It starts at 0 and if tps says 89% and you have checked that 89% is complete blade opening, then you have max opening. Lokar cable system is easy to adjust and check. 0 resets every time that the ignition starts. Checked and verified that throttle opening is max opening.
When good is not enough, Camshaft time again.
- Thread starter Kent mosby
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I would take the car for a hard romp. Hook up a vacuum gauge and hammer it. Note vacuum reading at full throttle, top of RPM window in each gear, especially high gear.
I recall us chatting about the combo and my first reaction to the lift on the cam was that it was small for a bigger inch engine. I'd have something in the 600+ area in it.
I compare what you are doing to a marathoner running while breathing through a straw. They won't perform best when struggling for oxygen. Cam lift is a choke point, EFI body may be another.
I recall us chatting about the combo and my first reaction to the lift on the cam was that it was small for a bigger inch engine. I'd have something in the 600+ area in it.
I compare what you are doing to a marathoner running while breathing through a straw. They won't perform best when struggling for oxygen. Cam lift is a choke point, EFI body may be another.
TT5.9mag
Two atmospheres are better than one
Yup that’s about the gist of it. But in all the efi instructions I’ve read, and systems I’ve set up, the first thing they tell you to do is verify that the pedal opens the blade(s) completely. Next is to do the tps sync. Almost all of the “wizards” are the same. So if a person follows the directions and does the tps sync correctly then the pedal corrolates to throttle opening. You actually want to test it (and do the sync) with the pedal, not the linkage.
Interesting enough the Mopar Performance crate 505 ci RB with the 509/292 hydraulic cam with 9:1 (Stage V heads) made 500hp. This is according to Frank Adkins publication, which also states that the 10.25:1 set up with stage IV heads, equipped with 2.14/1.81 valves produced 545hp utilizing the same camshaft.
PRH
Well-Known Member
I seem to recall hearing reports of independent dyno tests of the MP 500” crate motors where they didn’t quite live up to the advertised numbers.
I’ve don’t a fair amount of work on stage 6 heads, and the ootb flow numbers are quite poor(less than 260).
I guess what I’m saying is I’d have been pretty surprised if one of those actually made 545hp on the dyno here.
(Edit- my 2001 MP catalog shows the P4876692 crate engine to have 11.25:1cr, and made 575hp/625tq).
That being said, I suspect if Kent’s motor was plucked from his car as it sits, and set up on an engine dyno……..I don’t see how it wouldn’t be in that 545hp range.
As for the 292 cam vs Kent’s……..the Hyd @248@.050 would have a longer timing event at the valve than the solid @244@.050, and the lash for that solid would use up any net valve lift advantage it shows on paper.
Ignoring any criteria that isn’t about making more power………I’d be looking at a cam with about 20* more duration than the current piece.
Of course, that wouldn’t really fit in with the rest of the program.
I’ve don’t a fair amount of work on stage 6 heads, and the ootb flow numbers are quite poor(less than 260).
I guess what I’m saying is I’d have been pretty surprised if one of those actually made 545hp on the dyno here.
(Edit- my 2001 MP catalog shows the P4876692 crate engine to have 11.25:1cr, and made 575hp/625tq).
That being said, I suspect if Kent’s motor was plucked from his car as it sits, and set up on an engine dyno……..I don’t see how it wouldn’t be in that 545hp range.
As for the 292 cam vs Kent’s……..the Hyd @248@.050 would have a longer timing event at the valve than the solid @244@.050, and the lash for that solid would use up any net valve lift advantage it shows on paper.
Ignoring any criteria that isn’t about making more power………I’d be looking at a cam with about 20* more duration than the current piece.
Of course, that wouldn’t really fit in with the rest of the program.
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Well, I made some headway, progress but nothing conclusive.
1. All cylinders were heating up, no dead cylinders
2. Compression was 180 on 1 and 190-192 on the rest, Can't reach 4 and 6 without pulling headers off which involves removing motor mounts and lifting the motor.
3. Plugs a bit rich but I just lost an 02 sensor and the only running was 5 minutes to check the temps of the headers.
4. Rockers (440 source 1.6RR) show some wear on the shaft on the right side. They will be replaced with 1.5 RR
5. All lifters look the same, no unusual wear patterns, Cam looks great but I have not pulled it. I suspect if the lifters are all great that the cam will look good as well.
No time to drain the radiator and remove the front of the motor today to access the cam directly. That will be Friday or Saturday.
1. All cylinders were heating up, no dead cylinders
2. Compression was 180 on 1 and 190-192 on the rest, Can't reach 4 and 6 without pulling headers off which involves removing motor mounts and lifting the motor.
3. Plugs a bit rich but I just lost an 02 sensor and the only running was 5 minutes to check the temps of the headers.
4. Rockers (440 source 1.6RR) show some wear on the shaft on the right side. They will be replaced with 1.5 RR
5. All lifters look the same, no unusual wear patterns, Cam looks great but I have not pulled it. I suspect if the lifters are all great that the cam will look good as well.
No time to drain the radiator and remove the front of the motor today to access the cam directly. That will be Friday or Saturday.
If all the lifters looked good to me, like this one, would you resurface them? Buy new? Or use as is (just kidding)? These were from Oregon cams when I bought the cam. About 2000 miles and 80 trips down the 1/4 mile.
Plugs have been running pig rich for a while.
Agree, this happened after the O2 sensor went bad. Prior to the last races, they were fine. Was checked back in August.
TT5.9mag
Two atmospheres are better than one
If you’re running a new FT cam you have two options. Buy new lifters and have them refaced. Or reface the old lifters you already have. As always IMO and if you ask me I’m always right.
The Howards EDM lifter is a good option if your going .600+ on the lift, and/or increasing the open pressure to handle a more aggressive lobe profile.
Good luck with your project, Sir.
Realizing that you have access to a flow bench and dyno, would you spec anything less than .600 at the valve to get the heads into their potential?
FWIW: there is a Green 68 Cornet out of Idaho with a stroked RB that runs very well every year in thin air 6500da+. Speaking with him, I believe he runs the P4349268 Purple Shaft 324/324-620-112. I don't believe he is a 540ci, but that car lifts the left front off the ground constantly, and he is low 6 second 1/8 mile car.
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PRH
Well-Known Member
How I approach street/strip combos is to make a list of the priorities influencing the cam choice, in order of importance.
In Kent’s situation, I put compatibility with his EFI system at the top of the list.
I’m not any kind of EFI tuning wizard, and I don’t know how radical of a cam his system will tolerate before it gets outside of the parameters it can easily deal with.
So, that being the main criteria I’m concerned with, I wouldn’t be looking at the types of cams that would allow the motor to realize the “full potential” of the TF240 heads.
AndyF made over 700hp with those heads, so we know they’re capable of that.
I don’t see Kent’s motor even getting close to that.
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A light resurface on the cam lifter face will bring back the proper convex shape to the crown.
Your good used lifters are mated to the cam you have now, so you want a fresh proper surface to mate to the next cam that is going in.
☆☆☆☆☆
I'd keep them matched to the cam and buy new lifters, and have Oregon cams resurface the new lifters as well before using.
Unfortunately, I have removed them and when I got off the lift, I forgot which way they went. Coin flip. New cam ordered. Today I hope to check lift, duration and degreeing again on the existing cam before removal.they are very smooth. There is a layer of oil on them. So the pic is not as clear as what they actually are.
Great question, something I need to consider. I will check today. (4 am here so not in the shop, yet).
Plugs are ngk zfr6f-11g heat range 6. These were selected long ago and I am not familiar with the importance of heat range. Trick flow heads recommend autolite 3924 which says heat range 9. What is the significance of the heat range?
Those appear to be EDM lifters with the little oil hole in the center. That's a good thing! I think only Comp and Howards sell those - one uses a larger hole in the center (iirc Howards has the larger hole). I use the Comp versions in the avatar.
mayhem
Well-Known Member
Those look like some good quality EDM lifters. Send them to Ken at OCG for resurfacing and use with the new cam.
Solid roller.
That will have to wait until next year. I want to see how this goes first. The TC is on the list of options for upgrades.
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