408 Magnum stroker HEAD HELP!

[273]

It says the port length for the intake is shorter than exhaust, that doesn't seem right ? 4.50" vs 4.75"

 

[CDN68]

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[CDN68]

Im Not sure if you guys are included in the free shipping during the Black Friday sale or not. That’s a real arm twister.

I shared a picture of what i used for my comparison of the trick flow 190 heads ...... not sure about the black friday thing not a parts seller

 

[273]

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That's a 25-35 cfm difference in the meat of the curve .300-.500" probably at least a 50 hp difference on a decent engine. The SM aren't to bad for the level of head they are, like to see more .300" on them though, still probably make a decent 450-475 hp engine depending on the build.

 

[CDN68]

That's a 25-35 cfm difference in the meat of the curve .300-.500" probably at least a 50 hp difference on a decent engine. The SM aren't to bad for the level of head they are, like to see more .300" on them though, still probably make a decent 450-475 hp engine depending on the build.

Ya i was wondering how much of a difference that cfm would make but i thought it was close enough should have done more research . at least the heads are still bare could always spend more money and have them worked over i guess

 

[CDN68]

That's a 25-35 cfm difference in the meat of the curve .300-.500" probably at least a 50 hp difference on a decent engine. The SM aren't to bad for the level of head they are, like to see more .300" on them though, still probably make a decent 450-475 hp engine depending on the build.

Right now i remember i looked at the SM heads briefly but was looking at the CC's of the heads and didnt go further and i should have my fault

 

[273]

Ya i was wondering how much of a difference that cfm would make but i thought it was close enough should have done more research . at least the heads are still bare could always spend more money and have them worked over i guess

Most healthy built street engines seem to make around 1.8 - 1.9 hp per cfm at peak cam lift. 2-2.5 is possible.

 

[273]

Right now i remember i looked at the SM heads briefly but was looking at the CC's of the heads and didnt go further and i should have my fault

It's only a problem if your goal was 500 hp and or more. Your gonna need a little more flow and or cam/cr.
You probably can pick up some cfm with good valve job and a bit of bowl work and maybe some chamber de shrouding some of the head experts can help you there.

 

[CDN68]

It's only a problem if your goal was 500 hp and or more. Your gonna need a little more flow and or cam/cr.
You probably can pick up some cfm with good valve job and a bit of bowl work and maybe some chamber de shrouding some of the head experts can help you there.

Yes that was the hopes 500hp the compression ratio is going to be around 11.3:1 with a lunati solid roller .237@50 intake and [email protected] exhaust .566 lift intake with1.5 on intake and .578 on exhaust

 

[pittsburghracer]

It's only a problem if your goal was 500 hp and or more. Your gonna need a little more flow and or cam/cr.
You probably can pick up some cfm with good valve job and a bit of bowl work and maybe some chamber de shrouding some of the head experts can help you there.

I’ve never done it but probably should try it sometime is take a bare set of Speedmaster heads and open the pinch up to 1.0-1.010 and give the intake side a nice 70-60-45-30-15 valve job for a 2.055 valve.

 

[CDN68]

I’ve never done it but probably should try it sometime is take a bare set of Speedmaster heads and open the pinch up to 1.0-1.010 and give the intake side a nice 70-60-45-30-15 valve job for a 2.055 valve.

I asked about getting bare SM heads from the guys here in calgary and they said no complete only ..... maybe a canada issue or just that parts store ?

 

[273]

Yes that was the hopes 500hp the compression ratio is going to be around 11.3:1 with a lunati solid roller .237@50 intake and [email protected] exhaust .566 lift intake with1.5 on intake and .578 on exhaust

I'm definitely no expert but my guess is you'll probably just fall a little short of 500 hp, depends on how important hitting 500 hp is to you ? Is possibly being 25 hp or so short that big of deal to you.

 

[273]

I’ve never done it but probably should try it sometime is take a bare set of Speedmaster heads and open the pinch up to 1.0-1.010 and give the intake side a nice 70-60-45-30-15 valve job for a 2.055 valve.

That would be cool, if it gave a decent increase would be an easy mod the average guy could get done.

 

[CDN68]

I'm definitely no expert but my guess is you'll probably just fall a little short of 500 hp, depends on how important hitting 500 hp is to you ? Is possibly being 25 hp or so short that big of deal to you.

I would rather do the work while everything is clean and apart . If that makes sense.

 

[pittsburghracer]

I asked about getting bare SM heads from the guys here in calgary and they said no complete only ..... maybe a canada issue or just that parts store ?

40% off from this place on Black Friday and free shipping.

Mopar Chrysler SB 318 340 360 170cc 65cc Aluminum Bare Cylinder Head

 

[CDN68]

40% off from this place on Black Friday and free shipping.

Mopar Chrysler SB 318 340 360 170cc 65cc Aluminum Bare Cylinder Head

Ahhh man well thank you for sharing and guess it sucks to be me for taking thier info at face value

 

[273]

Ahhh man well thank you for sharing and guess it sucks to be me for taking thier info at face value

I found out if you handle the duties yourself you can save the brokerage fees a lot of shipping companies charge. But it's a bit of work, calling, faxing, going to closest place you can pay duties probably airport.

 

[pittsburghracer]

That would be cool, if it gave a decent increase would be an easy mod the average guy could get done.

Where’s @Earlie A at. We have more tests for him. Lol

 

[273]

He’s our R&D team

 

[Earlie A]

I’ve never done it but probably should try it sometime is take a bare set of Speedmaster heads and open the pinch up to 1.0-1.010 and give the intake side a nice 70-60-45-30-15 valve job for a 2.055 valve.

What are you thinking here? Trying to get some gains without professional head porting costs?

 

[pittsburghracer]

What are you thinking here? Trying to get some gains without professional head porting costs?

Well my thinking is especially with guys that want to buy their own valves is a 2.02 and a 2.055 cost the same right? The throat is already on the large size right? The valve job on Edelbrock and Speedmaster heads kinda suck from the factory right? Most guys what a local shop to check their heads out so I’m thinking for about the cost of a competition valve job if they could possibly pick up 15cfm would it be worthwhile. Is 15cfm there to grab. Just thinking outside da box.

 

[Earlie A]

Well my thinking is especially with guys that want to buy their own valves is a 2.02 and a 2.055 cost the same right? The throat is already on the large size right? The valve job on Edelbrock and Speedmaster heads kinda suck from the factory right? Most guys what a local shop to check their heads out so I’m thinking for about the cost of a competition valve job if they could possibly pick up 15cfm would it be worthwhile. Is 15cfm there to grab. Just thinking outside da box.

I could get on board with this. I’ll start a new post so we don’t hijack this one any further.