[Tom Vaught]

I think that you are right on track with the duration and lift with your combination. Being a roller camshaft will also make the camshaft much more drivable. A 428 will eat that camshaft like it is nothing.

Tom Vaught

[72LuxuryLeMansLa.]

Originally Posted by Tom Vaught

I think that you are right on track with the duration and lift with your combination. Being a roller camshaft will also make the camshaft much more drivable. A 428 will eat that camshaft like it is nothing.

Tom Vaught

Cool! Now if you could just tell me WHY I chose that cam....

[72LuxuryLeMansLa.]

Originally Posted by amcmike

To be honest, I thought your original hyd roller cam choice for that combination engine size and gearing for your goals was spot on.

Plus, with that SCR, you should be able to run on 87 Octane intead of requiring premium which will save you money at the pump.

See my answer to Tom's post below

[65WJ]

Originally Posted by HWYSTR455

Yes. If you choose a cam with more lift that the head can use, like for example, in general, factory iron d-ports kind of max out on flow at about .469 . You can go a little higher than that, which allows it to be over .469 for a longer period of time, but 'technically', it doesn't flow expodentially more above that.

You can also choose duration that favors RPMs over 5500, but the heads won't flow much above that RPM. They kind of hit a 'wall' at around 5250. You can doctor them and get more, but then you wouldn't be doing a 'mileage/cruiser' build. Most factory cams slope off above 4800.

Here's a list of factory cams on Wallace Racing site:

http://www.wallaceracing.com/camcode1.htm

Here's flow info I picked up somewhere way back:

(attached)

.

very nice thank you.
Looks like an 068 ho cam and 1.65 rockers for me. (turbo 400, trans go kit, cont. 10 converter and ford 9in with 3.50 ratio)

patrick

[72LuxuryLeMansLa.]

Originally Posted by bobzdar

All these guys wondering why their pontiacs get such poor mileage need look no further than that massive power sapping th400 with non lockup converter and their distributor and carb tune. I picked up 4mpg swapping a th350 for a 4 speed, no other changes. Th400 would be even worse.

Since I need an automatic; would the th350 handle power and torque on the order of 450/450 ? I planned on using a continental torque converter.

[Evil Stu]

Originally Posted by 72LuxuryLeMansLa.

I planned on using a continental torque converter.

Good choice. Drives like a regular converter; you don't need to rev excessively to move the car, it just creeps in gear like it should. No slip at hwy speed but when you want get on it then it is Jekyll and Hyde. I got mine from Cliff R, I'd recommend calling him.

Stu

[bobzdar]

Originally Posted by Evil Stu

Good choice. Drives like a regular converter; you don't need to rev excessively to move the car, it just creeps in gear like it should. No slip at hwy speed but when you want get on it then it is Jekyll and Hyde. I got mine from Cliff R, I'd recommend calling him.

Stu

If it's not a lockup, it will slip on the highway. It might be less slip than a 'looser' converter, but it will still slip and that's lost efficiency.

[bobzdar]

Originally Posted by 72LuxuryLeMansLa.

Since I need an automatic; would the th350 handle power and torque on the order of 450/450 ? I planned on using a continental torque converter.

If it's in good shape and you don't run slicks it should be ok. If you plan to do a lot of drag work you might want to think about upgrading some of the internals.

I should add I don't have a ton of experience with autos, at least not in terms of racing as I stick with manuals. But, I've seen th350's live behind well running 455's without issue for tens of thousands of miles. They were usually rebuilt with a mild shift kit, which as I understand it helps them a bit due to higher line pressures and less slip in the clutches. Too firm of shifts and it shocks the internals too much which can break them.

A buddy ran a th350 for 20-30k miles behind a 455 running high 12's at 108mph without issue before he sold the car. I'm sure he was in that 450/450 ballpark, but he did not run slicks.

[Evil Stu]

Originally Posted by bobzdar

If it's not a lockup, it will slip on the highway. It might be less slip than a 'looser' converter, but it will still slip and that's lost efficiency.

Fair ball and quite right. What I should have said is that it behaves like the original converter without the excess slip associated with some performance converters.

Stu

[bobzdar]

Originally Posted by rohrt

The posts are scattered all over on the pro-touring site and on the ls1 site, but here is one that was decent.

http://www.ls1tech.com/forums/conver...o-ls1-mpg.html

I would sure like to see what that (Dur@.050 222/230 Lift@1.5 560/560 LC 112) roller cam woud do in the 428

I didn't see any over 24mpg except for the guy with a newer thunderbird (ie good aero). This is certainly achievable with a Pontiac, I think the OPs suggested 428 will be capable if the rest of the car matches and it is properly tuned.

[rohrt]

Originally Posted by bobzdar

I didn't see any over 24mpg except for the guy with a newer thunderbird (ie good aero). This is certainly achievable with a Pontiac, I think the OPs suggested 428 will be capable if the rest of the car matches and it is properly tuned.

I started my own thread to get more info on the MPG with LS motors.

To change (back) to the subject a little.

The cam the poster selected Dur@.050 222/230 Lift@1.5 560/560 LC 112 how would the area of the lobe compare say to the RAIV cam?

With the shorter duration, people might think much less power but with the higher lift would you have close to the same lobe area? Or maybe even more power if in fact you have more lobe area, just at a lower RPM due to the short duration? If so then here is where the KRE heads would allow you to take advantage of the rollers higher lift, where an iron head might choke the higer lift out.

This is all my thoery, would like to hear input from someone with more hands on dyno experience in this area.

[72LuxuryLeMansLa.]

Originally Posted by 72LuxuryLeMansLa.

What is the best way to determine the duration and LSA needed for a desired RPM range?

I have a 1972 Luxury LeMans with A/C. The car is a daily driver. I would like to keep it looking as stock as possible. This means that the stock tires and rims will remain on the car. I will convert the peg leg 2.73:1 rear end to a posi unit with gears that will keep the mileage and manners consistent with a highway cruiser. I will probably never race the car. I am wavering back and forth on using a 200-4r overdrive tranny or a th400(economy being the concern). Now that you know how I will use the car I will move on to my engine plans.

I am going to stroke a 400, probably .030" over, using PPR's 428 stroker kit (3" main, 4" stroke crank, 6.625" forged rods and 5.5cc valve relief flat top forged pistons). I will square and zero deck the block also. I am now leaning towards 85cc KRE D-Ports over SD prepped iron heads. I calculate the SCR to be 9.86:1 using the 85cc KRE's. The exhaust I am planning on is the Rare 2.5" headers with my existing 2.5" H-Pipe and magnaflow system.

Now on to the cam. I DO NOT want a rough idle. I would like a broad flat power curve and peak HP is irrelevant! I also want to use a roller cam. How do I choose what intake duration to use and also what lobe separation is appropriate? Making a w.a.g. I have chosen the:

PPR Tomahawk Hydraulic Roller Cam 270/278

Dur@.050 222/230 Lift@1.5 560/560 LC 112

#TC-01-HR Overlap 50

Any help on how to choose an appropriate cam for my goals will be appreciated.

If I milled the 85cc KRE's down to 79cc for an scr of 10.51:1 would the same cam work?

[Retlt0123]

To those familiar with flow numbers. does anyone know the flow numbers for 1969 number 47 heads they arent listed on Ron's page. are they the same as the # 46 ' s ?

[BVR421]

"A set of 250cfm iron from SD will cost at least $1680.00 while a set of KRE D-ports complete unported that will flow as much and have plenty upside, will cost $2037.01 shipped for a whopping $357 more!"

Better check your homework on that one. KRE Dports are excellent heads but nowhere near 260cfm more like 220 and several $100s more to get to 260

On the cam choice, my 428 has a Summit flat tappet 2802 that is nearly exact spec as the roller you look at.
Nice 700rpm idle, just a slight rump in the idle and is still ripping way beyond any prudent shift point.
I could live with a smaller 2801 but I dont think Id want a bigger cam as my Bonneville is supposed to be a street car like you say you want.. You may have a different tolerance. Of course mine is only about 375hp and there again I wouldnt really want more in a cruiser.

On the subject of cams, all these posts for cam ideas are tons of fun and we learn a lot (usually) by discussing them but when it comes time to buy one personally I call someone who specs out cams for customers on a daily basis. Ace, Dude, Butler, Spotty, Cliff, Bullet, P-Body, SD, et al. Pick one to trust and then dont be second guessing the expert! My opinion is when it comes time to get out the credit card, the cam recommended by and bought from, one of the respected Pontiac vendors, is going to be a lot closer to what you really need plus the other parts, valve springs etc will be right LOL If there is a big problem who ya gonna call? Summit? Hows that gonna work out?
After all we well meaning "internet experts" wont have to live with a problem, you will, and by extension the guy you buy it from, so hopefully that vendor is going to be very careful in advising you.

[72LuxuryLeMansLa.]

Originally Posted by BVR421

"A set of 250cfm iron from SD will cost at least $1680.00 while a set of KRE D-ports complete unported that will flow as much and have plenty upside, will cost $2037.01 shipped for a whopping $357 more!"

Better check your homework on that one. KRE Dports are excellent heads but nowhere near 260cfm more like 220 and several $100s more to get to 260

This is from the thread on Edelbrock D-ports: http://forums.maxperformanceinc.com/...numbers&page=3



11-01-2010, 09:44 PM
Rocky Rotella
Ultimate Warrior


Quote:
Originally Posted by Nicks67GTO View Post
Do you have any side by side results you could post?


Nick, peak intake airflow on my SF-110 was:

KRE D-port- 258 cfm
Perf D-port- 272 cfm


I'd say 258cfm is fairly close to the advertised 260cfm! Do you have any flow bench numbers on these KREs? Was Rocky Rotella wrong?

[P@blo]

Originally Posted by 72LuxuryLeMansLa.

I'd say 258cfm is fairly close to the advertised 260cfm! Do you have any flow bench numbers on these KREs? Was Rocky Rotella wrong?

This is old news, BRV421 hasn't said anything new. The fact that HPP didn't compare the KRE d-port to the Edelbrock aluminum head and instead chose the iron head speaks volumes. If they did the cat would be out of the bag.

Increase of 20cc runner volume for 10-12 cfm if that? Keep your iron head cores or at least buy the new Edelbrock d-port with no ambiguity in the flow numbers. Remember how magazines pay their bills, they are not going to bit a hand that feeds them.

Jim Hand tried the KRE heads and off they came so that should tell you something as well (he's into is marketing knowledge not product).

[Rocky Rotella]

Originally Posted by P@blo

This is old news, BRV421 hasn't said anything new. The fact that HPP didn't compare the KRE d-port to the Edelbrock aluminum head and instead chose the iron head speaks volumes. If they did the cat would be out of the bag.

Increase of 20cc runner volume for 10-12 cfm if that? Keep your iron head cores or at least buy the new Edelbrock d-port with no ambiguity in the flow numbers. Remember how magazines pay their bills, they are not going to bit a hand that feeds them.

Jim Hand tried the KRE heads and off they came so that should tell you something as well (he's into is marketing knowledge not product).

Pablo, I'm not sure which article you're referencing when you state that HPP compared the KRE D-port to an iron casting and not an Edelbrock D-port, but if it was the one where Cliff Ruggles was involved, the Edelbrock D-ports weren't even in development at that point. That article was published in the mid 2000's. The prototype Edelbrock D-port (read: first made) wasn't produced until late summer 2010.

I stand by the flow bench number I obtain using my bench. I will say with absolute certainty that the KRE d-port castings I have flowed on my bench (at least three different castings at different times) have ALL flowed near 260 cfm. I'm not saying that all KRE D-ports flow 260. The reports suggest that some lesser flowing castings had got out, and I admit that my testing is limited, but it's not correct to make a blanket statement saying that KRE D-ports don't flow as advertised.

As for Jim Hand not using them, he can explain more if he chooses, but his decision was based on port volume and not actual airflow. For the record, his flowed around 260 cfm too.

[P@blo]

My mistake Rocky, it was Carcraft not HPP. In the article they did find 40 horse on the 20 cfm increase though but wonder how a Edelbrock RPM head would have fared.

http://www.carcraft.com/techarticles...low_chart.html

AIRFLOW CHART
VALVE IRON 7K3 KRE ALUMINUM
OPENING INT EXT INT EXT
0.050 38 24 33 26
0.100 80 51 67 55
0.200 143 96 148 100
0.300 180 125 198 134
0.400 201 142 227 154
0.500 211 162 235 170
0.600 215 168 236 180
0.700 219 171 234 183

[Rocky Rotella]

No problem. I just wanted to keep the record straight.

I will tell you this, the Edelbrock D-ports are VERY nice!

[rohrt]

Originally Posted by HWYSTR455

Well, for me, it's been experience, no science at all to it. I'm a hobbyist, not an automotive engineer. I know what a factory 350 2bbl 68-72 LeMans runs like, and about every flavor of 400, 428, 455 in those years too, and use the way they were cammed from the factory as a reference. I've also used about every off the shelf aftermarket cam known to man in the search for one that worked for me, was like an entire summer I changed cams almost every weekend, no kidding. All my stuff was for a car I not only would horse around with on the street, but used as transportation too, so it had to idle, etc. With that in mind, I've found that LSAs less than 110 tend to 'dump fuel' as you call it, at lower RPMs. They also had more choppy idle. I use durations in the range of 225-235 on 400s, with LSAs in the 112 - 114 range, and was always able to drive them anywhere. With more cubes, you can add 10 degrees. You can also review popular builds, and you will get expected results. The 400 you speak of has been done many times in many ways, doesn't have to be redesigned.

.

This was my favorite answer to the whole thread.

Originally Posted by HWYSTR455

Oh, and just to say, my current driver, the 71 LeMans, has a 400-based 461 e-head stroker, with a 4L80E, and 373 gears. It was based off a 550hp build, and probably makes 575+, has A/C, and I can drive it anywhere. It can sit in traffic or idle in the driveway for days, in 100+ weather, and I knock back 21-23 mpg in it. I had to check it multiple times, so know it's accurate. I have other board members that can verify that too by the way, it's not BS.

.

I want more detail on your build.

Originally Posted by bobzdar

I didn't see any over 24mpg except for the guy with a newer thunderbird (ie good aero). This is certainly achievable with a Pontiac, I think the OPs suggested 428 will be capable if the rest of the car matches and it is properly tuned.

I started my own post

http://www.pro-touring.com/showthrea...-your-LS-motor