Can a 400BBM w/cheap aluminum heads compete/dominate against the street LS?

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cojohnso said:
My 451 is close to thous numbers. I believe a little less compression. (Block was not decked to build. Thus pistons are a tick in the hole.) I'm guessing around 12.5:1. Running to a 1050 E-85 metered Holley 4150 style carb. (E-85 to accommodate the higher compression.)

The jury is still out on my thoughts of E-85? Does go thru more fuel. And needs flushing more frequent. Smells a little funny? Lol. But in Minnesota? ALOT cheaper than race gas.
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Do you use it out of the pump or can.
 
Absolutely can be done. The question is how much money you got honey ?9 second 383 Mopar turbocharged really isn't that hard. I would think a 300 shot on an all forged 400 would kick a lot of LS chubys in the face. One of my sons friends had a pretty badass trans am late model LS drag radials headers and some bolt on stuff it was pretty damn quick for what it was and on my way to work one morning lo and behold there he was waiting at the light I really had no choice he knew me any new my son who drives an SRT Challenger I snapped him at the light and gave that old 340 everything she had I could hear him but I could never see him I let off at about 90 because we were coming into town I guess I just got lucky LOL
 
greymouser7 said:
76 Aspen R/T,
400BBM block, speedmaster heads,
3 speed manual
1974 police 9 1/4 axle, am going to change gears-not selected
I have front and rear sway bars for it, and subframe connectors, 5 leaf-leaf springs,
Polyurethane bushings
...blank canvas, just wondering if building a street machine would be competitive.
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OK, here is my catch. What is competitive in your neck of the woods?
Would piston replacement be on the table?
Is a stroker kit on the table?
Or are we just working with a stock stroke low compression 400?
 
IQ52 said:
Well I've built 383 Chevies and 347 Fords but never a LS engine, so..............having no experience to fall back on I should stay out of this discussion.


Oh, and...........I've never built a 361, not in 2011......not ever. Now my Dad did build one in 1959, ran over 150 mph at Bonneville that year.
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What was the BBM that you built for the engine masters competition where they ran your engine without coolant? I thought that was a 361 based block., sir.
 
rumblefish360 said:
OK, here is my catch. What is competitive in your neck of the woods?

Competitive in my neck of the woods mostly includes late model mustangs, some vets, old muscle cars, and LS swap’s, and small block Chevy builds.

Would piston replacement be on the table?
Is a stroker kit on the table?
Or are we just working with a stock stroke low compression 400?
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Competitive in my neck of the woods is late model mustangs, Camaros, some vettes, small block Chevy‘s, LS swaps and classic big block cars.



Definitely pistons, appropriate machining,

only considering low compression with turbos-but again it seems like $$ pressure management $$ is computer controlled expensive;


It sounds ignorant, but I have heard on multiple occasions that the BBM make so much torque that they can break the block (especially large strokers),

a 451 or 470 seem awesome, also like a rabbit hole of upgrades and expenses (I have never found a machine shop with mopar torque plates;

and then stud girdle, aftermarket caps, torque plates, I am not sure what else, plus a few more things and I probably only know the beginnings of a high output engine.
 
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This...

seems like $$ pressure management $$ is computer controlled expensive;
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Is incorrect since, 1, you don’t need high pressure, 2. You don’t need a computer to control boost levels, 3. You can still use a carb. While a custom made boost friendly carb is pricey, there easily rebuilt way down the road vs a fuel injection set up.

Also your description of what I asked about what is competitive was more directed to an ET or known power FACTUAL level of the competition. Not what there driving.
 
rumblefish360 said:
Follow 4 out of 7, 7 C rules and you can get it done pretty OK.

Carb
Cam
Converter
Cog’s (gear ratio)
Cubic inches
Compression
Cylinder head

I’m not sure where you stand with the cylinder heads.
A Torque Storm super charger is not to expensive. But the upgraded fuel and ignition costs can be difficult to add on top when the bottom line is a concern. Gap your rings to suite and keep it under 10lbs. Oh! You’ll make power! And then what RRR said, a light car.
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Right before the r/b mopar splits between the cam and crank---------
 
greymouser7 said:
Yeah 500ci’s is an answer, but for the track. It would be hard to pass 8 gas stations with 500ci’s and a 3 speed auto
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Mine is better than a stock 69 coronet/440/4 speed was >but it is fuel injected . The problem is keeping my foot out of it mostly.
 
greymouser7 said:
What was the BBM that you built for the engine masters competition where they ran your engine without coolant? I thought that was a 361 based block., sir.
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500" 440.........Scroll down to La Roy Engines.

The 2011 AMSOIL/Mopar Muscle Engine Challenge, Part 2 - Mopar Muscle Magazine

Oh heck...check out the HP Engines entry on the same page. It is a 406ci 400 that made 608 HP. Forgot all about the Hollis Page entry.

If you can also get to the 9 pictures, the broken rocker shaft belongs to the 'Prism Racing' 400 block entry. They were winding it to 8,000 rpm while I was standing next to Billy Godbold of Comp Cams and he said, "You hear that? The valvetrain is screaming in agony!"

Aaaaaand boom...........

I think they still won the contest though.
 
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famous bob said:
Agree, were sucking hind tit , compared to the availability of G M stuff, anybody can make a G M run !
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I think Mopar does ok on engine options. It's body panels and support modules. You can literally build a 55-57 Chevy from all new parts. Ground up. Pretty much true for 66-70 Camaros and Chevelles.
 
IQ52 said:
500" 440.........Scroll down to La Roy Engines.

The 2011 AMSOIL/Mopar Muscle Engine Challenge, Part 2 - Mopar Muscle Magazine

Oh heck...check out the HP Engines entry on the same page. It is a 406ci 400 that made 608 HP. Forgot all about the Hollis Page entry.

If you can also get to the 9 pictures, the broken rocker shaft belongs to the 'Prism Racing' 400 block entry. They were winding it to 8,000 rpm while I was standing next to Billy Godbold of Comp Cams and he said, "You hear that? The valvetrain is screaming in agony!"

Aaaaaand boom...........

I think they still won the contest though.
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Jim, (based off the article provided, 340 cfm)

do your ported 906 heads flow better than basic aluminum heads then?
 
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Your questions are to my thought processes......well.........frustrating.

OOTB or ported.....potentially yes and then again no.

How many aluminum heads are out there? How is it possible to answer for all of them? The iron heads we have ported can be out flowed by any big block aluminum head we have ported. We have unwelded and non-epoxied RPM and Stealth test ports that flow 350 cfm.
 
LO23M8B said:
Yes they can. How do you test and adjust for it?
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I stay with one source so far. So its been consistent. But I believe weather conditions can affect E-85 more than gas. Higher humidity seems to like more jet on the carb. Cool crisp air less. (Actually the while motor likes cool crisp. And less everything? E-85 likes advanced timing. Cool crisp air doesn't seem to need as much timing.) If too cool? Then getting engine up to temp can be more challenging with E-85. Just what I have been seeing.
 
I never ran E-85 in my cars but have been thinking about it. But in our area it is very inconsistent. I've been looking at it on my tech2 on my x suburban and I've seen it from 50% to 90%. I haven't priced it in a can yet.
 
rumblefish360 said:
This...


Is incorrect since, 1, you don’t need high pressure, 2. You don’t need a computer to control boost levels, 3. You can still use a carb. While a custom made boost friendly carb is pricey, there easily rebuilt way down the road vs a fuel injection set up.

Also your description of what I asked about what is competitive was more directed to an ET or known power FACTUAL level of the competition. Not what there driving.
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Ignorance. (Mine)
I just don’t know ET’s. Though we have a track on the East in of town, which is an hour away from me in this metropolis.
 
LO23M8B said:
I never ran E-85 in my cars but have been thinking about it. But in our area it is very inconsistent. I've been looking at it on my tech2 on my x suburban and I've seen it from 50% to 90%. I haven't priced it in a can yet.
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Yeah E-85 with maybe some AVgas would be great, and affordable, but like you said inconsistent (we found it to be very dirty (perhaps less refined or filtered) in South East Georgia.
But 108 octane would cushion against detonation on a high end build.
I wonder if it would separate if mixed with AVgas while sitting-needing a binding agent?
 
cojohnso said:
My 451 is close to thous numbers. I believe a little less compression. (Block was not decked to build. Thus pistons are a tick in the hole.) I'm guessing around 12.5:1. Running to a 1050 E-85 metered Holley 4150 style carb. (E-85 to accommodate the higher compression.)

The jury is still out on my thoughts of E-85? Does go thru more fuel. And needs flushing more frequent. Smells a little funny? Lol. But in Minnesota? ALOT cheaper than race gas.
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Will you be taking your car to MITP? They have a race category, I have always thought about taking the Cuda but it is just not pretty, just functional.
 
John, just keep in mind this.....Remember those cheap heads will cost in the long run to make them right. Cleaning the ports and entire heads up from nasty casting and any port work you may want done. Making sure there are good springs and hardware installed. "Cheap" heads are well known for having parts that are less than standard for HP applications, so that's possibly more money outlay. Also the valve guides and seats and valve job in general needs going over.....just everything you'd normally do with any aftermarket head. It'snot just a "bolt on and go" kinda deal. The last thing you want is buying "cheap heads" and them ruining your entire build.

Look at what you've said. You want a Jim Laroy type build.....and cheap heads. Cheap up front, but possibly very expensive out back. Think about that.

Just some friendly advice from an old friend.
 
greymouser7 said:
Yeah E-85 with maybe some AVgas would be great, and affordable, but like you said inconsistent (we found it to be very dirty (perhaps less refined or filtered) in South East Georgia.
But 108 octane would cushion against detonation on a high end build.
I wonder if it would separate if mixed with AVgas while sitting-needing a binding agent?
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Ya I don't know. I just use 110 out of the can. The way I figure it's good insurance and if I do have to put some pump gas in it I don't have to worry. It's just not that big a deal for the amount of street miles driven. Pump premium is like $3.20 a gal. and 110 is about 65 - $70 for 5 so if you run it 50/50 it comes out to approx. $8.50 a gal. Not to bad for a tank of race fuel. The first tank full is the killer after that it's not to bad.
 
Sublime one said:
Will you be taking your car to MITP? They have a race category, I have always thought about taking the Cuda but it is just not pretty, just functional.
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Who cares how it looks. This way you can get some base line numbers and have a fun day out.
 
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