LB4 stock heads High swirl vane removal

[It's just a six]

Re: LB4 stock heads High swirl vane removal

Anyone have a P.N. for an intake gasket off hand?

Are these standard size ports? http://www.ebay.com/itm/FEL-PRO-120...its=Model:Syclone&hash=item53f7553e2c&vxp=mtr

Port Style:Stock

Port Height (in):2.050 in.

Port Width (in):1.110 in.

Thickness (in):0.060 in.

Thank you.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

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.

Here is my friends 36 Chevy w/the same cylinder head I have.
http://www.youtube.com/watch?v=S7rCGda4Ab8

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

Was looking @ the LB4 cyl head.

I noticed the divider on the intake ports does not go flush with the rest of the machined surface.

Are all these heads made this way?




If so, by filling up the gap would help in tuning, help idle, etc. . Basically engine would run smoother if that gap is filled up.

 

[dgoodhue]

Re: LB4 stock heads High swirl vane removal

My factory heads are like that. I think all the LB4 have the recessed divider between the adjacent intake ports.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

My factory heads are like that. I think all the LB4 have the recessed divider between the adjacent intake ports.

Thanks,
having the LB4 heads made this way is almost like having a Siamese head, & believe me Siamese heads are crappy.

I always hated my Siamese inline Chevy 6 cyl head, horrible design.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

Ok,
so my friend is cutting one chamber seats to fit larger intake & exhaust valves.

I had cut down a 2.08" valve down to a 2.0" valve for the intake.
That is the largest intake valve I ever planned on using for those stock /junk heads.
Don't think a 2.02" intake is really show any much gain over a 2.0" intake valve.
Plus a 2.02 really does not leave much material between the intake & exhaust valves, most likely will cause a crack.

The exhaust, just a standard 1.60"

I will do a little more porting after the seats & throats are cut. just to blend it all in.
Do a decent valve job.
Then just a do a decent valve job for the stock sized 1.94" in & 1.5" exhaust valves.

I will then have my friend flow test the stock sized valves & non ported cyl & see what it will flow then he will flow test the chamber w/the larger valves installed.

The thing that is really apparent is that the long turn radius bowls are huge as compared to a "normal" SBC head non high swirl vane type.

I am thinking I should see a gain in airflow, but if not, hey it's an experiment & only cost my time & my friends time, no biggie.
I had surgery on my torn rotator cuff & am recovering from that. Got some time to kill, but really cant do much, too much pain & little movement right now.
No parts were bought for this experiment.

So slowly moving along,

 

[Z SKI]

Re: LB4 stock heads High swirl vane removal

Cool experiment so far...

Slightly off topic here but why don't you come out to the next SyTy meet that we do the second Saturday of every month in Torrance.. It would be cool to finally meet you... Just saying...

Back on topic... If you see the flow increase that you are looking for will you finish these up and try to run them??

See ya,

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

I would like to come out & just hang . Just hard to find time to do other stuff other than stuff w/my family.
Thanks for the invite.

If I see a good flow increase I would most likely not use them since the L-35's are a bit better right out of the box & they would just bolt on also.

I always had my mind set to eventually get some L-35's, unless I find some Brodix-8 heads w/straight plugs.

For what I have done to them, for me it is not hard to do, just takes time & patience, I have a lot a patience.

Also having friends that do porting & valve jobs & build engines for a living helps out tremendously.

Just hanging out w/my friends you would tend to learn something.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

Just an update, (not much of an update) my friend (does the flow testing) went on vacation, so no real updates.

I am going to try a couple different valve seat angles to see if there in any difference in flow.

With these heads, (limited in the high lift flow) I am going to try & get better flow @ low lift rather than later in the higher lift range.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

My friend sent me a quick email on the head I removed the high swirl vane out.
Preliminary results.

Don't know the lift points. Will get them.

#1 #5 #3
Stock 3 Angle VJ Ported big valve
23.5 23.5 28
43.5 46 57.5
63 64.5 82.5
82.5 83 111.5
101 100 134.5
115 115 149
122 122 162
124 125.5 173
126 126 181.5
126 127 187
126.5 127 190
127.5 127 193

194.5

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

My friend sent me a quick email on the head I removed the high swirl vane out.
Preliminary results.

Don't know the lift points. Will get them.

#1 #5 #3
Stock 3 Angle VJ Ported big valve 2.0"
23.5 23.5 28
43.5 46 57.5
63 64.5 82.5
82.5 83 111.5
101 100 134.5
115 115 149
122 122 162
124 125.5 173
126 126 181.5
126 127 187
126.5 127 190
127.5 127 193

194.5

for some reason , cant post the graph correct

 

[sytyguy]

Re: LB4 stock heads High swirl vane removal

 

[QWERTYphoon]

Re: LB4 stock heads High swirl vane removal

wow, are those numbers correct? That is a pretty big gains. How much time did it take? Still worth it you think? You gonna do a complete set?

 

[Damian]

Re: LB4 stock heads High swirl vane removal

Might have to do this to my L35s that are sitting in my garage.

 

[atomicmecha]

Re: LB4 stock heads High swirl vane removal

Anyone remember what L35's ran ported and un ported? They were pushing about 200 right? and the LB6 (2nd gen vortecs) were well into the 200's if I remember correctly?

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

Thanks Michael.:tup:

This was the exhaust flowed w/a 1.60" valve.

The chart starts @ .050" & in increments of .050"

28 is @ 0.050

194.5 is @ 0.650

If you could add that in the chart would be much appreciated.

Thanks again.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

wow, are those numbers correct? That is a pretty big gains. How much time did it take? Still worth it you think? You gonna do a complete set?

Yes those numbers are correct.

What took the longest was removing the high swirl vane, approx. 30 minutes taking my time.

The porting, I did not take a lot of time & I did not remove a lot of material.
The feedback I was getting on doing this mod was pretty negative, anything from, it will flow worse, why waste your time, we did this back in 92 & did not work then & it still is not going to work now. & so-on. So, in receiving what seemed to be so negative response's I hap hardily ported the cyl head..
I got the head free, my time, free?, & flow tested for free, just to see the outcome is all I wanted to see because my friend that works @ a cyl head shop told me years ago a customer did this mod & it really helped his cause & his was a N/A engine, so on a turbo engine I figured it will make a big improvement.

The flow numbers are not great, but I opened up the size of the port window so it has to really help on a turbo or supercharged engine.

I just wanted to see this mod done & flow tested to see if there was a gain.

As far as being worth it?
That all depends if you have some time to do the work yourself. I am sure a shop doing it is going to cost you. But, IMO, it is not that hard to remove the vane, porting,, there are things you need to know about, because you can cause a head to flow worse if ported incorrectly.

I have not planned on doing a complete set.
If I was to do a complete set, I will do it to a pair of L-35 heads.

Might have to do this to my L35s that are sitting in my garage.

I think it would be worth it, but a word of caution, my friend has heard some of the vanes are solid, & some are not.
In this particular case, this was a stock LB4 Syclone head.

Anyone remember what L35's ran ported and un ported? They were pushing about 200 right? and the LB6 (2nd gen vortecs) were well into the 200's if I remember correctly?

I seem to recall a stock head should flow about 145-152 ish cfm, note: my friends bench flow testing shows the head flows less than that.

The 1996 & newer Vortec heads can flow IIRC, up to 250 CFM, but @ that CFM level, the heads are getting really thin & that is done w/a 2.02" intake valve, my cyl head has a 2.0" intake valve.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal


Sorry guys, the numbers posted are for the exhaust.

My friend has not flowed the intake side yet.

He had emailed me the results but I did not see the numbers were for the exhaust.

Kinda makes more sense because the flow numbers were pretty low.

So when he flows the intakes, I will post those numbers.

 

[QWERTYphoon]

Re: LB4 stock heads High swirl vane removal

Stock Lb4 exhaust ports flow better than Stock L35's exhaust ports, I believe. I thought I saw a flow chart proving that. Just thought I would share that. If I am wrong please be gentile.

 

[It's just a six]

Re: LB4 stock heads High swirl vane removal

I'd have to look it up, not sure . The lb4 head I did work on , the larger exhaust valve I had installed is a 1.6" IIRC. The head is at my friends house where he dose the flow testing & porting. If the Cyl head flows good on the intake would anyone be interested in doing this mod to those LB4 or L35 heads? My friend does excellent porting work.