Hi, I’m in the process of building a 408 stroker (360) with the aim of 500hp. The cam I have is from Hughes SEH4652AL-6 which they put together with stroker kit. This is mainly a street car which is a B body and I was after some advice on the intake choice and is there anybody running this cam on the street? Cheers
408 build
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stixx
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Most important: what cylinder heads are you going to use? Stock or aftermarket?
360duster
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what kind of compression and rear gears are you running? Streetable for sure with the right gears / converter….but don´t expect it to be tame and idling at 750 rpm at the stoplight.
Michael
Michael
stixx
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^This. What he says... you need more gear and a higher stall
converter with that cam.
dragfish
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I run the hughes 3842 solid in my car with 3200 converter and 3.55 gears edelbrock rpm intake 750 HP holley I updated my springs with beehives and run PRW stainless rockers car has a lope and runs real good.Motor is 40 over 360 9.5 compression.
You're going to need to do some work to those Edlebrock heads to hit the 500 hp mark. The heads are a limiting factor. Here's my build thread...
408 Build Thread
408 Build Thread
I know gear choice recommendations can be all over the map, but I originally went with 3.73's on my 410 stroker van, as a compromise, and is a good choice for street/strip, very streetable and best of both worlds but as I'm doing more strip than street now just went ahead with a 4.10 swap. I don't do burnouts on the street anymore at all as all it takes for that is a sneeze and its a stupid long burnout until i let off....but I now run low psi drag radials and do rolling acceleration runs. The pull is phenomenal with all that traction and 4.10's. And cruising at 65-70 mph max isn't bad at all, IMO. I'd recommend doing calculations with rear gears, tire diameter and each trans gear and compare the numbers to best match your intentions.
What I would do.....
Port match a RPM intake to the heads which should also be ported. Zero deck the pistons and run a gasket thinner than .050. Use a 1-3/4 header tube into a 2-1/2 exhaust pipe at a min.
3.23 gears?!?! Ummmm, no....
3.55’s? Maybe
Use a first class converter.
If you're goal is 500hp you'll have to give low end torque to get that peak hp at a higher RPM. With a 3.23, it will drive like a pig at low rpm's on the street even with a high stall converter. Ask me how I know.
autoxcuda
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What tire diameters/sizes are you guys running that are suggesting rear end ratios?
1stgen, What octane of gas are you planning to run. Not sure 10.9:1 is going to run off pump 91 octane.
Notice dragfish runs 9.5:1
1stgen, What octane of gas are you planning to run. Not sure 10.9:1 is going to run off pump 91 octane.
Notice dragfish runs 9.5:1
A408Cuda
Well-Known Member
Would a smaller cam make it more street-able? If so how do you determine the cam size, I've often been confused about the real difference between say the OP's .573 and .590 and say .566 and .583 does it really make that much difference? seems like such a small change.
Increasing camshaft lift has the effect as increasing duration, except doesn't change the opening and closing points on the lobe
MOPAROFFICIAL
Oogliboogli
You're gonna have some decent cylinder pressure closing the intake valve @45 or earlier if they used the usual suspects when it comes to piston choice. If the heads are made to work right, it'll make some good torque. I would consider better exhaust valves when the dynamic is high on pump gas.
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nm9stheham
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Gas octane in the UK and Europe is Research Octane Number (RON), not the average of Research and Motor Octane Numbers that we use in the US, which gives us our lower-appearing octane numbers. 1stgen's octane of 95 is similar to 90-91 octane in the US, and if he can get 98 octane, that is similar to 93 octane in the US.
Just running some numbers on the Dynamic CR, starting with a 10.9 static CR and making an educated guess on the advertised duration of the Hughes cam being around 298* (which is the .050" duration + 52 degrees) gives a DCR of 8.2-8.3..... With his AL heads, I think that is manageable, but needs proper attention to tuning. I have run iron heads, with quench, at 8.3 DCR on 93 US octane, but had to limit total timing some.
Hopefully, he has set up the gasket selection and piston deck height to get some quench, which will help. Maybe he can share that info.
nm9stheham
Well-Known Member
Hey MO. What would you consider to be 'better exhaust valves', and what is the particular reason to change them under these circumstances?
Once again thanks for the reply’s, this is a big learning curve for me The pistons Hughes specified are icon forged -13cc dishes piston at zero deck with a fel pro race head gasket 4.180” x 0.39” also giving a cylinder pressure of 186psi
Cheers Mark
Cheers Mark
dragfish
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I have no highway time yet have a 255 tire non drag radial on it and spins rather easily.I have 275's on my Cuda and 3.55's and 70 is no problem cruising.
MOPAROFFICIAL
Oogliboogli
Get super alloy Ferrea valves on the exhaust side.
Lift has a direct impact on HP. Not so much torque. The idea of lifting the valve high is to take advantage of the heads high flowing capabilities. If it has them.
Duration is where the rpm band is determined and yes a smaller cam lowers the rpm band in which it operates in. You have to be careful because a small cam has the timing events closer together and this can cause cylinder pressure to sky rocket. Thus making pump gas impossible to run.
Most cam manufacturers will list an operating rpm range where the cam should perform in. Crane goes as far as to even list the cruise rpm band in which there cam will perform in.
Most other companies will list the cams power band range. Hughesengines has a listing in there tech pages on where a cam should be making power T a min and max if you follow there suggested parts to work with the cam being used.
Without getting into cam talk, because it can get deep quick & be a little confusing, just follow the suggested parts list that the cam works with best. Cam manufacturers can play with the cams timing and ramps to come up with some pretty slick results. Unless you understand this kind of stuff, I suggest the K.I.S.S. Method.
(That would be, Keep It Super Simple)
Otherwise, you’ll end up on the phone with Comp or Crane or ..... talking about everything and then some more about the whole deal for the cam. They will want to know EVERYTHING about the whole deal. So be prepared to have every little detail about your car, trans, rear gear and tires & and wht you want to do or expect from it.
If your well prepped and spend the time on the phone, chance is, your going to be REAL happy with the custom grind your going to get.
nm9stheham
Well-Known Member
Comes out at 10.8 SCR so that part agrees with the earlier data.
Is the 186 psi cranking pressure computed or measured?
You do have a decent quench gap with that setup; that is good.
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