LB4 stock heads High swirl vane removal

[It's just a six]

I went & picked up my friends stock Syclone head. The heads have been seasoning for a long time in his back yard.:rotf:

I started to see if the vane is solid or hollow.

So far it seems to be solid .

I did some removal of the vane & opened up the intake port some.

I took about an hr on one intake vane removal & intake porting,

Before removal:



After some removal:





Intake ports





Took the valve springs off & found this, umbrella seals, not stock correct? They also had the stock little o-ring seal on the valve stems.



The tool I use for porting is a Makita variable speed grinder.
I am not doing heavy removal as you can w/my friends heavy amp Milwaukies.

 

[Logan]

Re: LB4 stock heads High swirl vane removal

What's the goal?

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

What's the goal?

To see if I can get any significant gains over a stock head w/the high swirl vane removed.

Wanted to have a bolt on head that still uses an EGR valve for smog checks.

I do not have an L-35 head, so I am seeing how the stock LB4 head will work after modding.

 

[Don W.]

Re: LB4 stock heads High swirl vane removal

I'd have to look at my original heads, but is the port really that small? Looks tiny in the pics.

 

[atkonkler]

Re: LB4 stock heads High swirl vane removal

Good luck! Very interested to see if they can be an improvement over the stock setup! Keep this thread going!

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

I'd have to look at my original heads, but is the port really that small? Looks tiny in the pics.

Yes they are really that small & the reason these are the worst flowing SBC/V-6 heads ever made, A.F.A.I.K.

Good luck! Very interested to see if they can be an improvement over the stock setup! Keep this thread going!

I will keep it going. I am a bit surprised @ myself already getting into it.

My friend said he will help me out by flow testing the head.:tup:

Not sure exactly what a stock LB4 head intake flows, but roughly high 150's? Anyone??

 

[dgoodhue]

Re: LB4 stock heads High swirl vane removal

I have seen 158cfm for the intake on LB4's. if you have access to flow bench that would ideal for before and after so you can rule out flow bench variances.

 

[Logan]

Re: LB4 stock heads High swirl vane removal

This would be a very interesting experiment. I have a good #181 L35 if you can do anything with it or want it for testing purposes. PM me if you can do anything with it.

 

[Snoman002]

Re: LB4 stock heads High swirl vane removal

If you go to put these on the truck please please dyno before hand and after.

I know we discussed this before, but I am glad to see you moving forward with it. For a true power comparison though a before/after dyno would be the best as a flow bench only shows so much.

Good luck!

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

I have seen 158cfm for the intake on LB4's. if you have access to flow bench that would ideal for before and after so you can rule out flow bench variances.

I will flow test a stock unported port, then the modded port flow tested.:tup:

This would be a very interesting experiment. I have a good #181 L35 if you can do anything with it or want it for testing purposes. PM me if you can do anything with it.

I can do some porting on that head, lets see how this LB4 head works out first.
Thanks for the offer & will contact you later.

If you go to put these on the truck please please dyno before hand and after.

I know we discussed this before, but I am glad to see you moving forward with it. For a true power comparison though a before/after dyno would be the best as a flow bench only shows so much.

Good luck!

I totally agree, a flow bench is not an indication on how the cyl head will perform in the real world, installed on an actual vehicle.
Something that flows great does not mean it will work great for a daily driver.

Also, just because a cyl head does not show any significant gains on a flow bench does not mean it will not improve power in an actual vehicle.

Thank you.
From what I gathered here from the expert head porters is that removing the vane will cause the head to flow less, velocity will drop, of course it will I am opening up the cross sectional area.
Hence removing that big obstruction that's in the way for air/fuel to enter the combustion chamber.

When a naturally aspirated engine is really dependent on higher port velocity, you do not want to port too big as the velocity will drop, causing poor low speed power.
I am just thinking yes, it will lose some low end power, some, but I think the gains mid to upper RPM power will greatly increase..

I am not good @ explaining theory's or just explaining how things work.
Like I said from the beginning, this is just an experiment so we all can learn some from it.:tup:

Yes a dyno would be a good test for these heads also.

Unfortunately, my engine is still running good & really do not want to tear apart a perfectly good running engine just for dyno testing. Although, I have dynoed my Sy a couple of times so it would be a good candidate.

If my engine has a problem like the engine smokes @ start-up then I could see me tearing it apart, but do not think that will happen soon.

Here are some more updated pics. Done some more porting. Cleaned up the head also.
Sorry if some pics are blurry. Old camera.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

The short side/turn radius does not seem to be any worse than my SBC 441 heads on the intake side.
The exhaust sort turn looks to be better.

Going from memory.

I need to dig out my 441 SBC heads.

Here is my awesome cylinder head. for an inline 250 6 Chevy.

Just to break it up a bit.:rotf:
It has a 2.08" intake valve & flows 320 CFM @ .600" lift.

 

[Don W.]

Re: LB4 stock heads High swirl vane removal

There is a beautiful Chev 6 hot rod around here that has been extensively modded. You might like it. I don't know the exact models but some Chev 6's have a head bolt casting right through the Siamese intake ports. He's removed that and uses a short stud that just comes up to the bottom of the port. Opens it up quite a bit.

12 port heads are just cool.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

There is a beautiful Chev 6 hot rod around here that has been extensively modded. You might like it. I don't know the exact models but some Chev 6's have a head bolt casting right through the Siamese intake ports. He's removed that and uses a short stud that just comes up to the bottom of the port. Opens it up quite a bit.

12 port heads are just cool.

Yes all 194-292 inline Chevy sixes are Siamese ports.

Here is the hot ticket when removing the intake bosses.

http://www.12bolt.com/250292_products/bolt_in_lump_kits

I had made a inline Siamease port Chevy flow better than stock, but made it too big because the port velocity went to low/slow. This testing were done many many years ago on those siamese port heads.
The aftermarket head is the way to go!
I made this intake for my 12 port head

 

[syclone0209]

Re: LB4 stock heads High swirl vane removal

Ported vortec for comparison.

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[TYTILIDIE]

Re: LB4 stock heads High swirl vane removal

Interesting. Looks like a lot of work tough. :lol:

 

[Don W.]

Re: LB4 stock heads High swirl vane removal

A "lump" kit? The local guy has a manifold he made himself, also uses fuel injection. FAST I think. He's also running a belt driven centrifugal supercharger. The thing runs in the low 14's. Not bad for a fully built shoebox. IE nothing removed from the car. Basically a cruiser.

Beautiful manifold. I would love to see that together. I like oddball setups, different from the norm. Maybe that's why I like the Syclone.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

A "lump" kit? The local guy has a manifold he made himself, also uses fuel injection. FAST I think. He's also running a belt driven centrifugal supercharger. The thing runs in the low 14's. Not bad for a fully built shoebox. IE nothing removed from the car. Basically a cruiser.

Beautiful manifold. I would love to see that together. I like oddball setups, different from the norm. Maybe that's why I like the Syclone.

Yep, a lump kit for the inline Chevy 6.
Thanks for the compliment on the manifold.

I got out my 441 SBC head for comparison to our LB4 head.

After looking @ the bowl area around the valve guide, the LB4 head looks to be a lot bigger, so I am thinking with this larger bowl area, it will possibly give a better chance for the airflow to change direction , which is a good thing.:tup:

Just looking @ the LB4 intake port now, it has to flow more air.:tup:

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

I need an intake manifold gasket so I can match the intake port.

What is the stock sized port Felpro P.N. & also a next size larger port Felpro gasket?

Anyone have one to donate to the cause? A used one is fine.

Thank you.

 

[Snoman002]

Re: LB4 stock heads High swirl vane removal

I need an intake manifold gasket so I can match the intake port.

What is the stock sized port Felpro P.N. & also a next size larger port Felpro gasket?

Anyone have one to donate to the cause? A used is fine.

Thank you.

Don't match the gasket, match the intake.

The gaskets are typically larger than the port, and the problem is if you match the gasket on both the manifold and head it can create an area with a larger cross section than the port upstream and downstream. This change in cross section causes the air to slow, then try and speed back up again and this is harmful to performance.

Match the intake and head together and try and keep the cross section consistent.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

Thanks for the tip.

The main thing I wanted to see if there is any mismatch going on.
I have an intake manifold to compare.

I hardly ever match the intake gasket to the entrance of the intake port itself. Usually the entrance of the cyl head intake port is too big anyways. I concentrate further into the port where it narrows down the most.
Unless it is a full out race engine. Then you would do a lot more detail to the intake port.