Hey Weasy

[Weasy2k]

Yea the 5vz-fe is like that as well...stock lift is around .330" and i now have them sitting at .370" coil bind aint far off. The guys who make the valve springs are amazed people are not killing their engines because of how soft the springs are.

The new valve springs have a much greater coil bind level and increase in pressure as well for all sorts of engine builds

As for flow rates...I agree that if you port and polish the hell out of the head and keep the stock lift/duration cams you will not see a gain as the cam truley is the doorway into the combustion chamber and if you do not allow enough time for the air to get in or out then whats the point of having that huge highway for the air to flow when there is a tiny doorway Hence why i notice a large improvment with these engines (the VZ's mostley) when just a simple cam upgrade is put in. NOW the test i would love to see is at a greater lift and stock ports vs mild port that is what i hope to test in the future.

As for the valves, i agree 100% that going with a larger head will not yield good results at all plus it would be very risky to have the head cut for those larger valves anyway. That is why i decided to bring out the high flo line as the valve is the stock size but just the area above the head is reshaped to allow for a greater airflow and it has worked very well with the 2jz crowd as well. I will be doing more tests with the valves in the future but i cant see how these cannot benefit most users, we shall see! I am building a stock block 5vz-fe with my modified valves, cams & valve springs to see what kind of power i can get N/A with stock intake manifold.

As for the 5vz-fe builds i do here..the only current "porting" is just a simple clean up

[4v6]

Originally Posted by Weasy2k

Yea the 5vz-fe is like that as well...stock lift is around .330" and i now have them sitting at .370" coil bind aint far off. The guys who make the valve springs are amazed people are not killing their engines because of how soft the springs are.

Yeah theyre pretty softly sprung on these ( and the 1uz too) but it helps to keep from loading the cams and helps make power by virtue of mechanical losses being lower.

Originally Posted by Weasy2k

The new valve springs have a much greater coil bind level and increase in pressure as well for all sorts of engine builds

Cant remember what the exhaust springs are rated at now...One other thing i noticed was the point of coil bind appears very close to the valve caps touching the stem seals. A modification of the guide bore locations could help get us a higher lift if the new cams make the engine respond to a lift increase.

Originally Posted by Weasy2k

As for flow rates...I agree that if you port and polish the hell out of the head and keep the stock lift/duration cams you will not see a gain as the cam truley is the doorway into the combustion chamber and if you do not allow enough time for the air to get in or out then whats the point of having that huge highway for the air to flow when there is a tiny doorway Hence why i notice a large improvment with these engines (the VZ's mostley) when just a simple cam upgrade is put in. NOW the test i would love to see is at a greater lift and stock ports vs mild port that is what i hope to test in the future.

Deffo one to be investigated.

Originally Posted by Weasy2k

As for the valves, i agree 100% that going with a larger head will not yield good results at all plus it would be very risky to have the head cut for those larger valves anyway. That is why i decided to bring out the high flo line as the valve is the stock size but just the area above the head is reshaped to allow for a greater airflow and it has worked very well with the 2jz crowd as well. I will be doing more tests with the valves in the future but i cant see how these cannot benefit most users, we shall see! I am building a stock block 5vz-fe with my modified valves, cams & valve springs to see what kind of power i can get N/A with stock intake manifold.

Should do well with it Johnny. How much to ship a 5vz block (bare) and heads to me?

Originally Posted by Weasy2k

As for the 5vz-fe builds i do here..the only current "porting" is just a simple clean up

Nice one matey, you clearly have a good grasp of the subject!

One thing i was thinking about was the exhaust valve sizes. I havent crunched the numbers yet as it depends on the exhaust port flows vs intakes and what the ratio comes out as.
AId hazard a guess that a turbo app would likely benefit from a larger pair of exhausts if these are undersized, which if we check the intake valve vs ex % comes out as :29mm/34mm= 0.85 (85%)
We could go as high as 0.9 (90%) but we'll have to see what we get on the flow figures first and see if we can derive a benefit from going a little larger there.

[Weasy2k]

Yeah theyre pretty softly sprung on these ( and the 1uz too) but it helps to keep from loading the cams and helps make power by virtue of mechanical losses being lower.

Thats very true, I just hope people dont think they can run those springs hard and expect them to hold for a long time as they will be surprised!

Cant remember what the exhaust springs are rated at now...One other thing i noticed was the point of coil bind appears very close to the valve caps touching the stem seals. A modification of the guide bore locations could help get us a higher lift if the new cams make the engine respond to a lift increase.

According to the tests done here int and exhaust were the same rate. At least the 5vz one. Also the part numbers in the pars catalog (toyota) showed them as being the same thing as well. You bring up a great point about how close we are getting to the valve stem seal....DANG i wonder what that number is as i have some serious cams that are going to go into my big 5vz-fe build here. I can also just get valves made that are longer which raises the retainer up by a bit.

Should do well with it Johnny. How much to ship a 5vz block (bare) and heads to me?

The shipping will cost as much as the dang engine is to buy, but if you are interested let me know via email and i can figure something out for yea.

Nice one matey, you clearly have a good grasp of the subject!

One thing i was thinking about was the exhaust valve sizes. I havent crunched the numbers yet as it depends on the exhaust port flows vs intakes and what the ratio comes out as.
AId hazard a guess that a turbo app would likely benefit from a larger pair of exhausts if these are undersized, which if we check the intake valve vs ex % comes out as :29mm/34mm= 0.85 (85%)
We could go as high as 0.9 (90%) but we'll have to see what we get on the flow figures first and see if we can derive a benefit from going a little larger there.

Another thing to look into for sure as i would love to provide a perfect matchup for people to buy stock size intake with a oversized exhaust. Something to look at as well, what i currently do is run a tad longer duration and lift to the exhaust cam for people who are running forced induction, this has seen GREAT results on my trd s/c 5vz tests (25whp vs 15whp gain with standard same duration cams)



I personally am just planning for N/A builds so my "specs' are going to be different then most of those FI guys

[4v6]

Few quick measurements later.....

Spring free length=41mm
Spring length at zero lift=34mm
Seat pressure=40psi

Compressed length (coil bound) 22.4mm
Pressure to compress to coil bind=105psi

Spring seat shim dimension =0.6mm

Valve guide height (intake)=12mm (exhausts)= 9mm

Stem seal to spring seat height ( no shim) ( intakes)=16.30mm (exhausts)=13.3mm

Any use to you matey?

[Weasy2k]

Hrmm defiantly can be helpful i am always looking around at different things.

I do know that the mz's benefit flow wise by the valve stem size reduction from 6mm in the vz's to 5.5mm in the mzs. The guide is also almost 1/2 the size as the vz's guides which can see helping keep the flow less turbulent.

On this V6 build here i am actually converting to a 5.5mm guide (for other reasons) and stem valve (high flow design that i have) i wish i had the flow bench now so i can really see if there is a difference

[4v6]

Itll probably improve by a couple of cfm Johnny rather than give a huge gain, thats what ive found so far, lots of little things adding up.
Waisted stems deffo should make an improvement- ill put one in the lathe and turn a little off the o/d and let you know how it stacks up.

[Weasy2k]

Did you want some reduced valve guides? I am making several sets of smaller ID guides so if you need a set let me know and i can addon to it.

[4v6]

What material are they made from Johnny? Ideally id like to use phosphor bronze rather than the present cast iron items.

[Weasy2k]

Yep thats what they are going to be

[4v6]

(ears pricking up with interest).

Got a few things to finish this end before i go balls out on the 1mz, needless to say, ill have all my "good parts" from yourself when i start a playin.

[4v6]

(ears pricking up with interest).

Got a few things to finish this end before i go balls out on the 1mz, needless to say, ill have all my "good parts" from yourself when i start a playin.

Oh btw, the stud set is A1 matey. Did a check and dont even need to reduce the stud length to clear the cam gears, got about 5mm clearance, fits like they were made for it.

[Weasy2k]

Dang you are lucky! I dont think the 5vz guys have that luck...i have to check...