PRC LS6 CNC Cylinder Heads W/ MS3
#23
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From: Hackettstown, NJ
how much pv clearence do i need? and is there any write that would explain valves..... i notice one size vales will give you more clearence am i correct? and what is better abotu one size or antoher? thanks again
#24
Originally Posted by 35thls1ss19
how much pv clearence do i need? and is there any write that would explain valves..... i notice one size vales will give you more clearence am i correct? and what is better abotu one size or antoher? thanks again
A larger valve (to some extent) will help the head flow better. A larger valve however will hurt P/V clearence.
There is a point where you can have too large of a valve. On the stock cubic inch LS1 most head companies dont go over a 2.055 valve, and I dont see any suggesting a 2.10 or bigger valve. This of course if the intake valve I am talking about.
Companies like AFR/ETP will use a 2.08 valve in their 225 heads but you need the right cam now to take advantage of the heads.
A 224/224 cam setup has no reason to use a 2.08 valve. That is where the AFR 205 or ETP 215 head is a better setup.
I am only using AFR and ETP as examples as they have consistance heads, where as other companies have a stage 1/stage 1.5/stage 2/stage 2.5/stage 3/stage 4 etc. The different stages aren't consistant from head company to head company so it is just easier to use AFR and ETP as examples.
Most suggest between .060-.080 clearence to be safe. You can get away with less but why take the risk?
As far as one size valve better then another?
That depends on the heads. Many companies use specific valve sizes as they feel that is the best valve size for their head design.
If you look at the "budget" heads thay typicially use stock valves. The porter knows stock valves are going to be used and therefore the goals is making the best port for stock valves.
Now you take a budget head and throw a larger aftermarket valve in there with the correct valve job and it will probally produce better flow numbers, but now it isn't a budget head.................
#25
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From: Hackettstown, NJ
so am i guess a valve job is not cheap? haha I was also considerin goin with a smaller cam and a budget head like u suggested in my last thread... but i am nto sure what cam would get me my goal of 450ish.... any sugestions anyone?
#27
Originally Posted by 35thls1ss19
so am i guess a valve job is not cheap? haha I was also considerin goin with a smaller cam and a budget head like u suggested in my last thread... but i am nto sure what cam would get me my goal of 450ish.... any sugestions anyone?
#30
LSxGuy widda 9sec Mustang
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From: Texas and Qatar
Originally Posted by ynkssws6
what was termin8or running? stock heads? Cause he has a HUGE shot and MS3, it would be nice if he chimes in
On PtoV, I have run as little as .045" on intake side, and .060" on exhaust, but I wouldn't recommend it for sane people, nor build one that tight for customers. My Daily driver has about .060"I/.075"E and I'm happy with that, no clearance problems with my .610" lift cam, 6800 rev limiter and 59,900 mile comp 918's, lmao.
#32
Here are the intake number on my PRC 2.5's. I run a 230-236 XE-R .595-.610 112 lsa with a ported FAST and LS2 TB. All work including SD tune done by ProStreet MotorSports (Phil99vette). We're at 460-470RWHP and I can drive it in bumper to bumper DC traffic.
300 205
.360 230
.420 260
.480 280
.540 295
.600 306
The fax cam through poorly so I couldn't read the exhaust for posting. These heads work.
300 205
.360 230
.420 260
.480 280
.540 295
.600 306
The fax cam through poorly so I couldn't read the exhaust for posting. These heads work.
#33
LSxGuy widda 9sec Mustang
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From: Texas and Qatar
Originally Posted by JoeyGC5
Ya'll living on the edge in Lubbock
Got any shirts in yet?
Got any shirts in yet?
I do carry a few spares and necessary tools for when mine finally break. My brothers 98 T/A broke a 918 at 3000 miles with the same cam as mine. They 'should' make it just long enough until my head swap which I'll have the PRC springs on.
I think there are a few white T-shirts left.
#34
Originally Posted by -Joseph-
I do carry a few spares and necessary tools for when mine finally break. My brothers 98 T/A broke a 918 at 3000 miles with the same cam as mine. They 'should' make it just long enough until my head swap which I'll have the PRC springs on.
I think there are a few white T-shirts left.
I think there are a few white T-shirts left.
#35
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From: Hackettstown, NJ
i am goin to call jason at TSP before i order.... but i am think i am goin to go with the Torquer v.2 Camshaft which is a tad smaller and then i will go witht he PRC 2.5 5.3 heads. Will this smaller cam give me enought pv clearnece to spary and will i put down some good numbers? thanks for all the replys guys
#36
This is the PM I received today from Jason regarding a set of heads for my Magic Stick cam and nitrous.
Originally Posted by Jason 98 TA
Matt the PRC CNC ported version of the dart is what I prefer honestly. That head works really well & has good p/v. The 5.3l ms3 friendly heads I stopped doing. The LS6 & dart work so well that I dont really do the 5.3 anymore!
#38
I called up Jason at TSP today as well and was told the same thing. I ordered my Dart 225CC heads with the MS3!! I can't wait to put it in and finally have some #'s people can go off of. Jason told me the cam will clear with flycutting as well.
#39
Sorry I'm slow jumping into the thread guys! We've been running around like fools lately!!
The LS6 cylinder head is really really hard to beat for the money. I would take the LS6 style head over the 5.3l head now that we finally finished the new LS6 port. With stock valves it flows better than the bigger valve 5.3l head & for less than the price of the 5.3l stage 2.5 head you can get a stage 2.5 LS6 head with 2.04 intake & 1.60" exhaust valves for 320+cfm flow @ .600! The other great option is the new cnc programs we have going together for the Dart heads, the Dart heads will allow for better p/v & big air flow. This cylinder head will be designed for guys looking to run huge camshafts & run larger valves.
Jason
Texas Speed
www.texas-speed.com
806.866.0734
The LS6 cylinder head is really really hard to beat for the money. I would take the LS6 style head over the 5.3l head now that we finally finished the new LS6 port. With stock valves it flows better than the bigger valve 5.3l head & for less than the price of the 5.3l stage 2.5 head you can get a stage 2.5 LS6 head with 2.04 intake & 1.60" exhaust valves for 320+cfm flow @ .600! The other great option is the new cnc programs we have going together for the Dart heads, the Dart heads will allow for better p/v & big air flow. This cylinder head will be designed for guys looking to run huge camshafts & run larger valves.
Jason
Texas Speed
www.texas-speed.com
806.866.0734
__________________
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
#40
Jason thanks for adding your input here, can you explain why the Dart head give meore P/V clearence please?
I must have missed that in all my reading.
Also what is the cost for your ported dart version heads?
Thanks
I must have missed that in all my reading.
Also what is the cost for your ported dart version heads?
Thanks