Well It Finally Happened

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MiradaMegaCab said:
I used a PurpleShaft 509 lift , 292 duration, 108LSA cam on a blown 9:1cr 360.
The 174 blower was only able to put out 6PSI.... I was at max blower OD then went with a smaller blower pulley, exceeding B&M's max OD RPMs....This resulted in no additional PSI as the smaller pulley had less surface area and I was having belt slip issues....
With your additional CI the 174 blower might not be able to keep up while using a cam with a lot of overlap.
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Yeah I was thinking the same thing. It ran great on the 340 though. I also am running a smaller than normal snout pulley as well. Also cam profile and heads effect the boost. I loved my blower but I guess its time to go with a normally aspirated engine with the Fitech EFI
 
superchargeddrt said:
That's what I hear. I was really wanting that 416 but they are a lot more expensive than the 408 and I'm having trouble believing that there is that much difference in performance. Where did you get your 408? Did you build it yourself?
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Why are they a lot more expensive? The only difference in price is the block. With minimal patience, they come up quite often for 500-800 bucks. Even if you get a 360 block for free, in the whole scheme of things, that isnt much difference. For that small difference, i like the bigger bore and less friction in the bottom end.... plus it aint much, but 8 cubes is 8 cubes. If a 360 block costs you something, it tightens up the small difference even more.
 
B3422w5 said:
Why are they a lot more expensive? The only difference in price is the block. With minimal patience, they come up quite often for 500-800 bucks. Even if you get a 360 block for free, in the whole scheme of things, that isnt much difference. For that small difference, i like the bigger bore and less friction in the bottom end.... plus it aint much, but 8 cubes is 8 cubes. If a 360 block costs you something, it tightens up the small difference even more.
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Well as luck would have it, the 340 block that I had under my work bench (a friend gave it to me) turned out to be a virgin block. I still have to get a set of main caps as they are missing). I am taking it to the machine shop tomorrow to have them look at a couple of nick's in the number 2 cylinder. It looks like going 30 over will take them out but I want to make sure before I order the Scat kit, might have to go 40 over.
 
superchargeddrt said:
Well as luck would have it, the 340 block that I had under my work bench (a friend gave it to me) turned out to be a virgin block. I still have to get a set of main caps as they are missing). I am taking it to the machine shop tomorrow to have them look at a couple of nick's in the number 2 cylinder. It looks like going 30 over will take them out but I want to make sure before I order the Scat kit, might have to go 40 over.
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Lucky dog!! Hopefully you can stay at .030 over. The main cap deal is abeeotch. Wish I had some here I'd give them to you.
 
I have edelbrock heads and 10.2:1 compression and it runs just fine on 93 octane. If you plan on going with a roller cam setup, make sure the lifters don't come up out of the bores too far or they won't pump up properly. 340's are well known for having this issue. 360's not so much.
 
yellow rose said:
Lucky dog!! Hopefully you can stay at .030 over. The main cap deal is abeeotch. Wish I had some here I'd give them to you.
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THAT'S the beauty of FABO. If someone has something another member needs a lot of times they will just say pay the shipping and it's yours. I sent a brand new set of Chevy rocker panels still in the box to a member here.

Yeah it is a bit of a beeotch BUT, and you're not gonna believe this, I have another friend that's gonna give me another 340 short block. This one is already 40 over but the block and crank might be worth keeping. I will use the caps and just get my engine align bored.
 
You might not want to run a thick gasket to reduce compression. Not when you're boosting it. High compression also doesn't work with boost.

What the heck is going on here?

I must have fallen a sleep in class.
 
Yes you did LOL. He is going NA.

OP, look at Edelbrock performer RPM heads to see what flows will easily get you to 400 HP. So your needed flows will be above that. Camming up to get the cam to flow to match that larger head flow will be needed, so but you sounds like you don't mind an engine that is a bit rough at lower RPM's so that is all good.

Personally, I see only limited cases to put on a blower with 10:1 SCR and put in a lot of cam overlap. I bet it would just push the lower end of usable RPM range up, and make it a peaky, high RPM only engine and blow a lot of fuel out the exhaust at low RPM's. Might make sense for an all out drag racer and a big blower. This all relates back to the comments in post #50.

Leadfoot said:
I run a good solid 10:1(and change) with iron heads on 85 and have no problems. I'd like to hear some real numbers fro the guys at lower elevations. I'm at 5k feet and have never had so much as a knock or ping.
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FWIW, I have run 10+ on iron heads and with 87 had knocking at elevations typically in the 1000-2000 ft range. And I could not put all the timing advance in that some would like to do, even on 93. DCR was around 8.4. So your cam may be large enough to lower your DCR too, even at sea level.
 
nm9stheham said:
Yes you did LOL. He is going NA.

OP, look at Edelbrock performer RPM heads to see what flows will easily get you to 400 HP. So your needed flows will be above that. Camming up to get the cam to flow to match that larger head flow will be needed, so but you sounds like you don't mind an engine that is a bit rough at lower RPM's so that is all good.

Personally, I see only limited cases to put on a blower with 10:1 SCR and put in a lot of cam overlap. I bet it would just push the lower end of usable RPM range up, and make it a peaky, high RPM only engine and blow a lot of fuel out the exhaust at low RPM's. Might make sense for an all out drag racer and a big blower. This all relates back to the comments in post #50.

FWIW, I have run 10+ on iron heads and with 87 had knocking at elevations typically in the 1000-2000 ft range. And I could not put all the timing advance in that some would like to do, even on 93. DCR was around 8.4. So your cam may be large enough to lower your DCR too, even at sea level.
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Thanks for replying, I really appreciate the info. Hey what does everyone think about theses heads
.Shocker 185 Mopar CNC (Sold in Pairs) - PROMAXX Performance Products
 
I am at about 3000 feet here near Edmonton Alberta, my 408 is 10.1:1 compression and runs fine on pump premium with W2 iron heads. I have 24 initial and 34 total timing all in by 28-2900 and so far no signs of detonation on pump fuel. I have finally put some miles on it including a good long highway drive. This is my first stroker and I am amazed at its mild manners when driven easily. Best of both worlds, an animal when You get on it and very civilized when taking it easy.
 
A lot of detonation issues can be handled with good closed chamber heads, tight quench, and dished piston in a stroker. Additionally some of the new coatings help also. I am also running Evans waterless coolant in this engine. I have not really put it to test yet to verify it's claims, they say it can help fight detonation by preventing localized boiling in cylinder heads thus eliminating hot spots. I am very happy with my 408 so far.
 
cpearce said:
I am at about 3000 feet here near Edmonton Alberta, my 408 is 10.1:1 compression and runs fine on pump premium with W2 iron heads. I have 24 initial and 34 total timing all in by 28-2900 and so far no signs of detonation on pump fuel. I have finally put some miles on it including a good long highway drive. This is my first stroker and I am amazed at its mild manners when driven easily. Best of both worlds, an animal when You get on it and very civilized when taking it easy.
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Can you tell us your cam? That has quite an impact on the DCR and thus any tendency to detonate.
 
nm9stheham said:
Can you tell us your cam? That has quite an impact on the DCR and thus any tendency to detonate.
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20170924_125152.jpg
 
cpearce said:
I am at about 3000 feet here near Edmonton Alberta, my 408 is 10.1:1 compression and runs fine on pump premium with W2 iron heads. I have 24 initial and 34 total timing all in by 28-2900 and so far no signs of detonation on pump fuel. I have finally put some miles on it including a good long highway drive. This is my first stroker and I am amazed at its mild manners when driven easily. Best of both worlds, an animal when You get on it and very civilized when taking it easy.
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Wow, I can't wait. Yours seems like a great package, thanks for the info!
 
superchargeddrt said:
Wow, I can't wait. Yours seems like a great package, thanks for the info!
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If you search my posts my entire build is listed including dyno numbers, might provide you with some insight. Good luck with your project!!!
 
OK, thanks. Just curious on this one. One has to just guess on the Hughes cams' advertised durations since they don't give the numbers. Guessing 48* longer than .050" lift duration, your DCR works out to around 8.0 at sea level but drops to 7.4-7.5 at 3000' of elevation. So that is a significant drop in DCR, and is helping you stay away from detonation-land.
 
nm9stheham said:
OK, thanks. Just curious on this one. One has to just guess on the Hughes cams' advertised durations since they don't give the numbers. Guessing 48* longer than .050" lift duration, your DCR works out to around 8.0 at sea level but drops to 7.4-7.5 at 3000' of elevation. So that is a significant drop in DCR, and is helping you stay away from detonation-land.
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That is why the 106 degree lobe separation angle, to fool it into thinking it has more compression at this elevation. It is very responsive to throttle input even at lower rpm.
 
i would absolutely build another smaller displacement supercharged engine. I was lucky to stumble on my original B&M blower kit for a SBM, so when they day comes I will build a supercharged 372 using the older 3.79 stroker cranks.
 
cpearce said:
I think it's called w2 408 build
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Wow! 544 @ 5400RPM! Thoroughly impressed! I haven't decided on a cam but here's some of what I was thinking.
Scat forged rotating assy. I am ordering it unbalanced because my machinist is going to balance it anyway.

Edlebrock Victor CNC ported heads. I am ordering them bare and having my machinist go over them and Install 2.05 intake valves, and check the valve guides (I want to be safe here), I won't have the money to do it again.
I am using my existing comp solid roller lifters and my Crane gold roller rockers.
Intake I was thinking about going with the Victor.
Compassion I was looking to be close to 10.5 :1 to 11:1.
I will fill in the cam when I research it a little more. In the end I am looking to use the car pretty much like you are going to use yours. I am going to finish reading your thread. Thanks for you help.
 
superchargeddrt said:
Wow! 544 @ 5400RPM! Thoroughly impressed! I haven't decided on a cam but here's some of what I was thinking.
Scat forged rotating assy. I am ordering it unbalanced because my machinist is going to balance it anyway.

Edlebrock Victor CNC ported heads. I am ordering them bare and having my machinist go over them and Install 2.05 intake valves, and check the valve guides (I want to be safe here), I won't have the money to do it again.
I am using my existing comp solid roller lifters and my Crane gold roller rockers.
Intake I was thinking about going with the Victor.
Compassion I was looking to be close to 10.5 :1 to 11:1.
I will fill in the cam when I research it a little more. In the end I am looking to use the car pretty much like you are going to use yours. I am going to finish reading your thread. Thanks for you help.
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Those Victor heads look like very nice pieces. You should have no problem making big power with that set up.
 
cpearce said:
Those Victor heads look like very nice pieces. You should have no problem making big power with that set up.
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Yeah I'm scraping the money together for them. I won't be able to dyno the engine because I'm using FiTech EFI and I would have to remove all of the wiring to do it.
 
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