They were thin as cast.
Is 426ci 360 a small block?
- Thread starter IQ52
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They were thin as cast.
Timing, valve lash, fuel mixture, but mostly another 600 rpm. Trying to get this Super Victor to work. This is the first time I've had so much intake for an engine that adding the 2" Super Sucker didn't help. With or without it the two curves look exactly the same.
Have been running with the $136 Summit 1-5/8 headers and will now switch to TTI 1-5/8 to 1-3/4 step headers.
Good looking engine.
Switching to the TTI headers gained us 12 HP peak and 1 lb-ft and 1 hp average gain from 3000-6000 rpm. And they only cost an additional $520.
So we switched carbs from the 850 Mighty Demon (column 1) to 1050 RS Race Demon (column 2) and then the last pull of the day w/ 2" spacer (column 3).
RPM...........(1) TQ/HP............(2) TQ/HP...........(3) TQ/HP
3000.............434/248...............456/260.............450/257
3200.............447/273...............466/284.............466/284
3400.............442/286...............477/307.............480/311
3600.............453/310...............491/336.............490/336
3800.............451/327...............484/350.............496/359
4000.............454/346...............494/376.............499/380
4200.............494/394...............511/409.............518/414
4400.............511/428...............536/449.............532/446
4600.............529/463...............547/479.............546/478
4800.............538/491...............547/500.............554/507
5000.............543/517...............549/522.............557/530
5200.............536/531...............547/541.............543/538
5400.............530/545...............533/548.............535/550
5600.............517/551...............530/565.............528/563
5800.............512/556...............514/567.............519/573
6000.............506/578...............504/575.............510/582
6100.............499/579...............501/582.............504/585
6200.............487/574...............491/579.............497/587
6300.............485/582...............593/591.............497/596
6400.............481/586...............480/585.............486/592
6500.............470/581...............470/582.............477/590
6600.............463/582...............462/580.............466/586
6700.............443/564...............455/581.............457/583
I call it a 426 because it sounds better, but is actually 4.042" bore by 4.125 stroke for 423.5 ci, The dog is now only making 1.41 hp/ci on 91 octane.
So we switched carbs from the 850 Mighty Demon (column 1) to 1050 RS Race Demon (column 2) and then the last pull of the day w/ 2" spacer (column 3).
RPM...........(1) TQ/HP............(2) TQ/HP...........(3) TQ/HP
3000.............434/248...............456/260.............450/257
3200.............447/273...............466/284.............466/284
3400.............442/286...............477/307.............480/311
3600.............453/310...............491/336.............490/336
3800.............451/327...............484/350.............496/359
4000.............454/346...............494/376.............499/380
4200.............494/394...............511/409.............518/414
4400.............511/428...............536/449.............532/446
4600.............529/463...............547/479.............546/478
4800.............538/491...............547/500.............554/507
5000.............543/517...............549/522.............557/530
5200.............536/531...............547/541.............543/538
5400.............530/545...............533/548.............535/550
5600.............517/551...............530/565.............528/563
5800.............512/556...............514/567.............519/573
6000.............506/578...............504/575.............510/582
6100.............499/579...............501/582.............504/585
6200.............487/574...............491/579.............497/587
6300.............485/582...............593/591.............497/596
6400.............481/586...............480/585.............486/592
6500.............470/581...............470/582.............477/590
6600.............463/582...............462/580.............466/586
6700.............443/564...............455/581.............457/583
I call it a 426 because it sounds better, but is actually 4.042" bore by 4.125 stroke for 423.5 ci, The dog is now only making 1.41 hp/ci on 91 octane.
What was the size of the first carb?
Is the 1050RS a Dom. Flange?
Cam description/specs?
Is the 1050RS a Dom. Flange?
Cam description/specs?
The 850 Mighty Demon, is, well, an 850 cfm 4150. The Replaceable Sleeve Race Demon is the RS Race Demon with the large silver venturi sleeves for 1050 cfm and is also a 4150.
The cam is our design Comp street solid roller that makes 165 psi cylinder pressure @ 5000' elevation with 10.9:1 compression.
pishta
I know I'm right....
sure, the block is as small as a 273's. Displacement is through the roof though...whats life of one of these with that radical rod angle?
Well, the stroker never did dyno more than 601 HP but the '67 Dart has been on the road for over a year now. He just tied into his first 707 HP Hellcat. Said the poor Challenger didn't stand a chance.
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..................426 is the magical number, great work Jim,as usual...............kim.......
Well the owner has some supercharged Corvette he would like to beat. The car is back for some transmission work, a switch from 3.23 gears to 3.91, subframe connectors and power steering box change. We'll go through the engine and swap the out the ported ProComp/Streetmaster aluminum heads for our ported LAX iron heads we have laying around on the shelf. At least that is the present plan.
Put it in a Gremlin. Then give it back to him.
Okay I guess. But what about an AMC Pacer?
I think our LAX heads will out flow the ProComps. I plan on doing back-to-back flow tests on the same day.
racerhog
RacerHog likes his Mopars
Nice big small block.... 
Things still to test, but now we are getting somewhere.
Latest flow tests......2.05 intake/1.625 exhaust on both heads. Exhaust with 1-3/4" tube.
...........ProComp/Racemaster.................LAX................OOTB LAX
Lift................IN/EX...............................IN/EX..................IN/
.100............71/57...............................71/58..................57/52
.200..........143/122...........................143/124...............124/105
.300..........200/184...........................204/176...............184/143
.400..........248/221...........................250/214...............230/191
.450..........267/230...........................271/226
.500..........281/240...........................290/236...............255/187?
.550..........283/246...........................301/242
.600..........285/252...........................304/248...............257/201
.650.............N/A................................301/253
Latest flow tests......2.05 intake/1.625 exhaust on both heads. Exhaust with 1-3/4" tube.
...........ProComp/Racemaster.................LAX................OOTB LAX
Lift................IN/EX...............................IN/EX..................IN/
.100............71/57...............................71/58..................57/52
.200..........143/122...........................143/124...............124/105
.300..........200/184...........................204/176...............184/143
.400..........248/221...........................250/214...............230/191
.450..........267/230...........................271/226
.500..........281/240...........................290/236...............255/187?
.550..........283/246...........................301/242
.600..........285/252...........................304/248...............257/201
.650.............N/A................................301/253
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stixx
Well-Known Member
Impressive...
Hey now! Dontchoo be Makin fun of my Gremlin-driving-days! I GREMLINIZED plenty of 5.0 fox bodies!
Nice work Jim !!
So are are both sets max ported ?
Looks like the exhaust side flows a bit more on the pro comps .
Do you think you can get more out of the pro comps ?
Do edelbrocks and pro comps flow about the same ?
Or is one better ?
As always thanks for taking the time to compare and share results !!
Jim
So are are both sets max ported ?
Looks like the exhaust side flows a bit more on the pro comps .
Do you think you can get more out of the pro comps ?
Do edelbrocks and pro comps flow about the same ?
Or is one better ?
As always thanks for taking the time to compare and share results !!
Jim
pishta
I know I'm right....
yes, it still has small block heads...
I don't think there is anything such as max ported. I think you can always get more out of a cylinder head if you can just figure it out. I believe that there is more flow in both the LAX and the ProComp heads. I still believe that the Edelbrock is a better quality head. Flow wise, I couldn't honestly say.
So, balancing the cc's in the combustion chambers today and getting ready to assemble the engine and put it on the dyno. No pictures or technical data, as this is hopefully just a failure. I'd like to prevent dealing with the crap RAMM and others have to wade through presently.
RAMM
Well-Known Member
It's spring and I have a whole yard of dog crap to wade through--It gets surprisingly easy after some practice. J.Rob
So j-dot-rob, because of you, continuing to post, having practiced wading through the back yard. I was ashamed and thought I might try following your good example. Therefor..........
Once upon a time you could buy these LAX heads with no intake pushrod holes in them. When we entered the contest in 2010 they wouldn't let you use those heads so I never bought any. Now trying to make these heads from 2010 work on the stroker I had to figure out some way to get the cross sectional area up some.
The trouble is, you still can't open the top of the pushrod pinch/port roof as wide as the middle, because you end up grinding right out under the valve cover. We already have the non-offset Chevy 1.5 rocker arms from 2010, so we decided to do the best we could with what we have.
I did figure out that we could machine the top of the head above the pushrod hole and into the port and press in a solid bar with an oval button head, machine in a pushrod hole farther away from the intake port, use an offset rocker and open these heads so there was no pushrod pinch. As all this engine has to do is make as much horsepower as it did the last time, I think we are going to be okay with the set up in the pictures.
And before I go through all that other work, I think I'm going to go for the BPE cylinder heads.
Still, it's going to be interesting to see if these iron heads will make more power than the aluminum heads, as the iron heads have a slightly larger minimum cross section and the flow bench says a lot more air flow up top.
Once upon a time you could buy these LAX heads with no intake pushrod holes in them. When we entered the contest in 2010 they wouldn't let you use those heads so I never bought any. Now trying to make these heads from 2010 work on the stroker I had to figure out some way to get the cross sectional area up some.
The trouble is, you still can't open the top of the pushrod pinch/port roof as wide as the middle, because you end up grinding right out under the valve cover. We already have the non-offset Chevy 1.5 rocker arms from 2010, so we decided to do the best we could with what we have.
I did figure out that we could machine the top of the head above the pushrod hole and into the port and press in a solid bar with an oval button head, machine in a pushrod hole farther away from the intake port, use an offset rocker and open these heads so there was no pushrod pinch. As all this engine has to do is make as much horsepower as it did the last time, I think we are going to be okay with the set up in the pictures.
And before I go through all that other work, I think I'm going to go for the BPE cylinder heads.
Still, it's going to be interesting to see if these iron heads will make more power than the aluminum heads, as the iron heads have a slightly larger minimum cross section and the flow bench says a lot more air flow up top.
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