383 rebuild - old dyno results & new cam ideas

Drew,

The cam card you posted for the Crower 00471S, is the same cam I'm using in my SBC 400 for the TBucket, except it has a small base circle.

Again I've included a couple of other curves to compare the new camshaft with. The two custom grinds you posted on page 2 don't have enough info for me to create a cam file for Dynomation 6.

Custom grind #1: ADV DUR: 295/302
INT/EXH - Dur @ .050” Lift: 239°/246° RR: 1.5/1.5Gross Lift: .562”/.562” LSA: 109°

Custom grind #2: ADV DUR: 296/296
INT/EXH - Dur @ .050” Lift: 237°/237° RR: 1.6/1.6Gross Lift: .585”/.585” LSA: 108°

Where do you want to go next Drew???

DPSim05_CrowerHR00471.JPG
 
Rick,

Thanks again for the simulations!! At the moment I don't have any other ideas or recommendations for camshafts to use in the simulation software, I am waiting for a recommendation from Lunati though. If you don't mind we could input their recommendation and see how the power is affected, but I am thinking cams in the 235-240 @.050 range are going to have similar results.

How do you like the 00471 in your 400?
 
When your locked in with an advertised or @.050 spec camshaft profile as often here to stay in safe zone rpm for Street cruising a Powerfull tool is different LCA Lobe centerline angles and ground in or advanced / retarted Intake Centeline installed and checkef with a cam degree wheel.
Working in a typical street range 110-112 .
Race it's 99 degrees -108 & High Boost power adder 114-124 degrees range.
 
Rick,

Thanks again for the simulations!! At the moment I don't have any other ideas or recommendations for camshafts to use in the simulation software, I am waiting for a recommendation from Lunati though. If you don't mind we could input their recommendation and see how the power is affected, but I am thinking cams in the 235-240 @.050 range are going to have similar results.

How do you like the 00471 in your 400?

Sure, just let me know when you get the Lunati info and we can run another Sim.

I love it, it works great in my 1800 lb TBucket. Idles about 850 rpm and has a nice lope to it. Pulls
hard from about 3200 to 6200 rpm. It behaves nicely on the street with my 2800 stall converter.
But I think it would be even better with a 3200 stall converter, but concerns for the fluid temp will
increase with the higher stall when the ambient temps rise above 90°F in traffic. I have a passively
cooled Derale trans cooler. Plate-Type, Aluminum, Black, 19-Row, -8 AN, 7.438 in. x 13 in. x 2 in.

https://www.summitracing.com/parts/der-51908

FP01_CoolerLines_6173.jpg

But there will be differences in our experiences with the same camshaft. I'm only trying to get 1800 lbs
moving with a 2.73 low gear, where you accelerating 3300 lbs with 2.48 low gear. I would like to try that
Crower 00422, but there is always a snowball effect when you change just one thing. Would have to think
it thru and see just what would have to change. On the surface I can see the TC would have to change,
then a better trans cooler. Would it work with my compression ratio and not have clearance issues. Then
there is .......

But first would come a set of SS headers that I would design, been thinking about them for several years now.
 
short answer, yes head flow and torque are closely related

your gentlemen might want to read this and play with calculators
http://garage.grumpysperformance.com/index.php?threads/port-speeds-and-area.333/#post-72826


related info
USE THE CALCULATORS to match port size to intended rpm levels... but keep in mind valve lift and port flow limitations[/color]
http://www.wallaceracing.com/runnertorquecalc.php
http://www.wallaceracing.com/ca-calc.php
http://www.wallaceracing.com/area-under-curve.php
http://www.wallaceracing.com/chokepoint.php
http://www.wallaceracing.com/header_length.php


keep in mind
properly matching,
cam timing,
engine displacement,
compression,
and header design
has a huge effect on intake port flow efficiency
pistonposition2a.jpg


EXFLOWZ4.jpg

exhaustpressure.jpg

volumetric.gif

Grumpy, you have posted those diagrams hundreds? of times. This time I actually studied them. Now I see.
 
Grumpy, you have posted those diagrams hundreds? of times. This time I actually studied them. Now I see.
NHRA Super Stock Racing Mike .
But Grumpy's Rules allow Head Porting & cylinder head aftermarket swaps.

With 592 Hp I had in the last T/A build engine I calculated the world record holder 1969 RAIV Trans Am that runs 9.90 ET all steel body with bone stock unported cast iron RAIV Heads also.
He has 590-620 HP.
I was right in the ballpark.
Man the Trans Am was Super Powerfull last time I Street Raced It & I knew it just did not know how much Hp !
 
No updates with new cam suggestions but I did have a chance to start looking at the damage closer. So far I've removed the oil pan, intake, and upper valve train. Luckily the cam lobes, and more importantly the lifters, don't seem to have any abnormal wear. One of my major concerns was the lobes also failing and tearing up the lifters.

The only issue I've noted so far is one of the exhaust ports (cylinder 5) looks different than the others. All the exhaust ports but cylinder 5 have a flat black (sooty) look to them on both the head and valve; cylinder 5 has a more glossy appearance on the head and the valve looks cleaner than the others. The port is not wet or oily it just has a shinier appearance. Any idea what would cause this? Below are a few pictures of some of the exhaust ports.

Ports 3 and 5:
20190520_211106.jpg

Close-up of 5:
20190520_211154.jpg

Port 1:
20190520_211120.jpg

Port 7:
20190520_211136.jpg
 
if you pull the head, check the valve too seat seal carefully with some alcohol
you may find its leaking, or the cylinders miss firing, if you don,t pull the head remove that valves rocker,
and squirt 30 or so cc of alcohol in the exhaust port, watch if it drains over 10 minutes or so,
and remove the spark plug and see if the liquid drains past the valve seat/seal,
into the cylinder, obviously if it does the head comes off for relapping or repair

http://garage.grumpysperformance.com/index.php?threads/valve-seat-runout.15104/#post-86003
 
Cylinder 5 is not firing or mis-firing. The un-ignited liquid fuel has cleaned that valve. And the port walls are black wet.
Pull the head. You can then clean or replace those rusty head bolts.:rolleyes:
 
Good evening,

First - A huge thank you to all that responded, provided input/advice, and simulations for my project. I appreciate it.

Due to life throwing some unexpected curve balls my way I put my project on hold, and for much longer than anticipated. I worked on the engine when I could, but have been able to dedicate more time recently. I'll hopefully have the car back together and driving soon. Primarily waiting on my transmission to be rebuilt now. The engine is mostly complete, just need to install the intake and oil pan.

Originally I considered rolling in new rod and main bearings, and replacing the cam, without completely disassembling the engine to get it up and running quicker. I decided against that and did a complete teardown instead. I didn't want any contamination from the previous failure creating any issues.

I'm glad I chose to tear everything down. The heads were substantially corroded around a few of the water ports and had to be repaired. If I left everything together I would have had a leak sooner than later. My machinist sent them to be welded, then he re-drilled the port openings and milled the deck surface. I could hardly tell they were repaired when I got them back. While they were at the shop I had them check the valve seat sealing, everything was good.

I talked to every cam manufacturer I could think of (except COMP) to get their recommendations, they were all fairly close to each other. None of them suggested the large duration gap between intake and exhaust that COMP did. I chose a Bullet hydraulic roller ground on a billet core with a pressed on iron distributor gear. The specs are: 240 @ .050 intake, 245 @ .050 exhaust, .570 lift on both with 1.5 rocker, with a 108 LSA.

Unfortunately, I won't have any new dyno numbers for this rebuild. The shop that I went to originally no longer has a dyno, and everyone else with a flywheel dyno in my area will only dyno engines built by them. My primary reason for returning to the dyno was for the controlled break-in to help the rings seat, make sure nothing leaks (especially the rear main seal), and to be able to get a baseline tune before putting it in the car. For me, the power numbers were just an added bonus.
 
thanks for the update, good luck , let us know about further progress
 
Wow, it has been awhile since you last posted. I still have your sim files, so if you can post your cam card I will run another sim.
 
IMG_20230409_120907.jpg

Rick,

Here's a pic of the cam card for the new cam. Thank you for the offer, I'm interested is seeing how this one will look on the simulator.
 
keep in mind the crower cam RICKS T-bucket combo uses was selected to maximize the engine durability,
and provide very good street drivability, and provide decent power & torque in a street rod ,
that cam was not selected to maximize the engines peak power,
(a mistake almost everyone makes in cam selection, on the first few engine builds)
he should easily run very low 11 seconds to maybe high 10 seconds in the 1/4 mile with the correct traction and launch techniques
yet still be able to drive the car on several hundred mile trips without over heating or other issues in stop and go, traffic,
something in low rpm drive characteristics ,that a significantly longer duration cam might not provide.
the secret to building a decent combo is matching the parts selection and drive train gear ratios and cars weight, to the intended use,
while maximizing the long term durability and maximizing the useful torque curve in the rpm range the car will see under 90% plus of its life span.
 
What was your motivation to continue looking at other camshafts? This is only simulation software and only shows a small decline in performance, I've no doubt you will be pleased with the Bullet camshaft!

Average HP/TQ from 3000 to 6600 RPM is
Sim07 = 422/463
Sim08 = 410/451

DPSim07_Lunati_vs_Sim08_Bullet.jpg


Installing the Bullet cam dot-to-dot will be 4° advanced and will give you a DCR of 7.69. What octane gasoline are you planning on using?

DCR_BulletCamshaft.jpg

I took your cam card and brightened it up and reduced it's screen size. You can right-click on the image , select "Copy Image". Then you can Right-Click in the folder of your choice on your computer and select Paste if you want your own copy.

Bullet_HR_CHS299-304-08HR_570_570.jpg
.
 
Rick,

Thank you for providing more simulator info! I appreciate it.

I forgot to mention in my earlier post that the machine shop had to mill a little extra off the heads when they were reworked. The combustion chambers are now 68 cc's and should bring the static compression to slightly over 10.5. I previously ran 93 octane and plan to run it again.

I initially got a few recommendations but didn't order anything until much later. I later talked to a few more manufacturers to get a broader opinion before deciding. On the intake side the recommendations ranged from 236 - 244 with anywhere from 0 to 8 degrees of extra exhaust duration, lifts ranged between .550 and .575, LSA's were between 108 and 110.
 
Also,

The cam card said to degree the intake lobe to 104. I don't have my notes any longer but installed straight up the cam was off that number. I advanced the crank gear and got the correct 104 intake centerline. If I'm not mistaken, the gentlemen at Bullet mentioned not grinding any advance into the camshaft. Not sure why.

I hope I didn't end up over advancing the cam.
 
I forgot to mention in my earlier post that the machine shop had to mill a little extra off the heads when they were reworked. The combustion chambers are now 68 cc's and should bring the static compression to slightly over 10.5. I previously ran 93 octane and plan to run it again.
The corrected DCR is 7.85 with 68cc combustion chambers. You might be able to run 87 octane. If you are using 93 your DCR could be higher, like around 8.1. But keep in mind that 93 octane is not available everywhere, so if you go out of state 91 octane might be all you can get. All I can get in Oklahoma is 91 octane.

DCR_BulletCamshaf_Corrected68ccChamberst.jpg

The cam card said to degree the intake lobe to 104. I don't have my notes any longer but installed straight up the cam was off that number. I advanced the crank gear and got the correct 104 intake centerline.
If you installed the Intake Centerline at 104°, then the Exhaust Centerline is 112°, therefore the cam is installed 4° advanced. This would be the same as installing "dot-to-dot", that is what meant by having 4° advanced ground into the camshaft. What Centerline did you install the Bullet cam on? Was that dot-to-dot?

Installing the cam "Straight Up" is the same as "Split Overlap". The intake centerline and the exhaust centerline equal each other. This is zero degrees advance.

Some people get confused when they see the LCA = 108°, but the ECA and the ICA when added together = 216°. That is because the LCA is the number of degrees between the intake and exhaust lobes and is measured in Cam Degrees. The ECA and ICA are measured in Crankshaft Degrees. The crank rotates twice for every one rotation of the cam, therefore 216° / 2 = 108° = ECA = ICA = Cam @ 0° Advance

Bullet_TimingDiagram.jpg
.
 
installing the cam strait up or even 2-3 degrees retarded ,
(what Id do, but of course you have a myriad of options)
might make more sense as it will move the whole power curve up about 150-200 rpm,
and significantly reduce any tendency toward detonation
why not try it both ways and see what you prefer:like:

as its only going to take you a hour or two to change, to either advance or retarded or strait up,index

related threads
http://www.jegs.com sells this KIT
Comp Cams #249-4796
http://www.jegs.com/i/Comp Cams/249/4796/10002/-1

and you can buy these

MOR-62191 $44 (wheel)

MOR-61755 $47 (SBC)
MOR-61756 $47.(BBC)crank sockets

SUM-900188 $17 (piston stop, head off)
SUM-900189 $6.95(piston stop, head on)

TFS-90000 $94.95 (degree kit)

youll also want two flat tappet solid lifters and two weak check springs

pro-66838_w.jpg


http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-66838&N=700+115&autoview=sku

http://www.totalengineairflow.com/tools

http://www.summitracing.com/parts/cca-4760

cca-4760.jpg





you could buy these from summit racing or similar parts from jegs
scan0001.gif
 
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