243 head question... larger valves or more compression
04-24-2017, 07:27 AM
#22
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[QUOTE=JakeFusion;19601406]That's not how you look at velocity. You look at coefficient of discharge.
See this post for more information on it: https://ls1tech.com/forums/generatio...l#post19592368
The TEA Stage 2 heads are the ones with the larger valves. Stage 1 is the stock valves like AI.
What would I do? Well since I had the same dilemma back in 2013 when I bought my heads, I did TEA Stage 2. And would do them again, everyday of the week. They've made 520rwhp on a 346 with a 234 duration cam. And over 550 on a 408 with a pretty mild cam... think 239 duration. But more importantly, they are fast as hell at the track. The flow numbers don't mean jack. They make real power and run fast. Flycut your pistons and run as much compression as you can. Aim for 8.7:1 DCR.
Btw, the valve job they do is the same ones TEA cuts into their TFS heads. And that's where most of the power is. QUOTE///
This is exactly why I went with TEA stage 2 243's. They always perform well from mild to big cams from 346-400+ ci. Should have mine at the track in the next few weeks. Expecting some quick times!
See this post for more information on it: https://ls1tech.com/forums/generatio...l#post19592368
The TEA Stage 2 heads are the ones with the larger valves. Stage 1 is the stock valves like AI.
What would I do? Well since I had the same dilemma back in 2013 when I bought my heads, I did TEA Stage 2. And would do them again, everyday of the week. They've made 520rwhp on a 346 with a 234 duration cam. And over 550 on a 408 with a pretty mild cam... think 239 duration. But more importantly, they are fast as hell at the track. The flow numbers don't mean jack. They make real power and run fast. Flycut your pistons and run as much compression as you can. Aim for 8.7:1 DCR.
Btw, the valve job they do is the same ones TEA cuts into their TFS heads. And that's where most of the power is. QUOTE///
This is exactly why I went with TEA stage 2 243's. They always perform well from mild to big cams from 346-400+ ci. Should have mine at the track in the next few weeks. Expecting some quick times!
Last edited by sillysspeed; 04-24-2017 at 07:33 AM.
04-24-2017, 11:24 AM
#23
While I will probably go with Land Speedon my current 416 build, I have used TEA on two previous projects.
99 TA 224 XE-R cam, old TEA Stage 2 5.3 heads = 418hp @ wheels the TEA heads have 128,000+ miles on the heads with the XE-R cam, ~15 years is pretty impressive quality to hold together. Had valve springs etc, with new valve seals this old package uses 1 quart of oil every 4,000 miles
91 RS 383 LS1 229/229 Morgan Motorsports v2.1 cam from back in 2001 one, TEA LS6 Stage 2.5 hand finished with NOS exhaust port, with TPIS LS6 intake 465 whp - I'm sure with a big cam they would make big numbers.
99 TA 224 XE-R cam, old TEA Stage 2 5.3 heads = 418hp @ wheels the TEA heads have 128,000+ miles on the heads with the XE-R cam, ~15 years is pretty impressive quality to hold together. Had valve springs etc, with new valve seals this old package uses 1 quart of oil every 4,000 miles
91 RS 383 LS1 229/229 Morgan Motorsports v2.1 cam from back in 2001 one, TEA LS6 Stage 2.5 hand finished with NOS exhaust port, with TPIS LS6 intake 465 whp - I'm sure with a big cam they would make big numbers.
04-24-2017, 09:51 PM
#27
I had my stock 243's from my Gen4 LMG 5.3 ported and milled by TSP-PRC, I went with the Stage 1 and had them milled roughly 0.010" which is 63cc chambers. Going from stock valves (2.00/1.55) to what PRC offers (2.02/1.575) would only gain 3-5 HP above 5k RPM on a sub 4" Bore engine that is mildly modded, according to TSP.
Not worth the extra $200 in my opinion. I found some "New" LS6 Hollow Stem/Sodium Filled valves and dropped those in instead. If you are going for a max effort engine, then the larger valves will gain you a few extra ponies.
More Compression will benefit the entire rpm range and will yield more power and torque.
Not worth the extra $200 in my opinion. I found some "New" LS6 Hollow Stem/Sodium Filled valves and dropped those in instead. If you are going for a max effort engine, then the larger valves will gain you a few extra ponies.
More Compression will benefit the entire rpm range and will yield more power and torque.
04-26-2017, 12:43 PM
#33
FWIW,
PRC Doesn't Polish the chambers. I purchased their stg. 2.5 LQ9 heads with new heads. While their website clearly shows Polished chambers and is misleading, my heads were 100% untouched. I asked about it and they said that it's not included with the As-is price.
Wish I would have known this prior to purchasing because I would have paid to have them polished up and or smooth out the rough casting surface.
Hope I didn't miss out on anything by not having this done ...
I'd go with the TEA if I were in your shoes now.
PRC Doesn't Polish the chambers. I purchased their stg. 2.5 LQ9 heads with new heads. While their website clearly shows Polished chambers and is misleading, my heads were 100% untouched. I asked about it and they said that it's not included with the As-is price.
Wish I would have known this prior to purchasing because I would have paid to have them polished up and or smooth out the rough casting surface.
Hope I didn't miss out on anything by not having this done ...
I'd go with the TEA if I were in your shoes now.
Last edited by BlwnLs1GTO; 04-26-2017 at 12:49 PM.
04-26-2017, 01:36 PM
#34
TEA CNC'd the chambers on mine, creating a new chamber shape and quench area. The softening does the same thing - to change how the flame front travels and to alter the quench area/shape. TEA does it with the CNC - but for like another $100 or so they will go back and hand finish and create a mirror polish on the chamber which takes it to another level.
04-27-2017, 02:03 PM
#36
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have you compared all the flow #'s vs $$$? last i checked awhile ago texas speed stage 2.5 were the best bang for buck for a 400 hp or better ls1. just my one cent.
04-27-2017, 02:24 PM
#37
PRC are probably the best bang for the buck. TEA stage 1 looks to have better velocity in the middle, and can be upgraded to TEA stage 2 later on. As far as the numbers are concerned, for a cathedral port 226cc and lower, TEA stage 2 beats just about everything... even aftermarket castings
04-27-2017, 02:29 PM
#38
If you are solely talking flow numbers of the tsp 2.5 ls6 head, the trick flow 220 as cast flows more than it does at mult points and has a better valve angle. We have the trick flows with a .650 titanium spring kit for $100 more than the stock ported tsp castings. And the trick flows are on a 3.9 bore and the 2.5 ls6s are on a 3.910 so cannot make a direct comparison but close enough.
The only issue is trick flow wont mill the heads in house So you are "stuck" with a 64cc chamber. The chamber is cncd but the runners are cast...which means there is ALOT of upgrades you can still do to them. You do have an option of a 2.04 or 2.055 intake valve for the same price though. The 2.055 valved head is considered an "ls2" head and as such is flowed on a 4inch bore. it doesnt show a change in exhaust flow...which is actually odd and possibly a typo or formatting issue. I can find out on that though. But you do get a brand nee head, brand new casting, new guides, etc. They are bronze, but we do also have the pm guides available pretty cheap to have installed if you dont want to shim your stockers or use roller rockers. They are also new stainless valves as well. Out of the box they are a good head. With some attention from the right people they are a GREAT head.
Another option that was huge a while back, but has been looked over lately.
Ive been over all of the tips, tricks, and info on about 5 different cyl heads out there comparing stock ported castings to aftermarkets, and in the end, we have sold 5 sets of trick flows in different iterations.
The only issue is trick flow wont mill the heads in house So you are "stuck" with a 64cc chamber. The chamber is cncd but the runners are cast...which means there is ALOT of upgrades you can still do to them. You do have an option of a 2.04 or 2.055 intake valve for the same price though. The 2.055 valved head is considered an "ls2" head and as such is flowed on a 4inch bore. it doesnt show a change in exhaust flow...which is actually odd and possibly a typo or formatting issue. I can find out on that though. But you do get a brand nee head, brand new casting, new guides, etc. They are bronze, but we do also have the pm guides available pretty cheap to have installed if you dont want to shim your stockers or use roller rockers. They are also new stainless valves as well. Out of the box they are a good head. With some attention from the right people they are a GREAT head.
Another option that was huge a while back, but has been looked over lately.
Ive been over all of the tips, tricks, and info on about 5 different cyl heads out there comparing stock ported castings to aftermarkets, and in the end, we have sold 5 sets of trick flows in different iterations.
04-27-2017, 02:38 PM
#39
That seemed very one sided so i will say the tsp head is a vert good budget head. They have new machines and programs and have changed quite a bit since moving. They are working their way up in cam design also. The stock castings that tsp cncs are a good budget setup, the only reason those customers went with tfs is the ability to upgrade later on with the same head and the marginal cost difference. If a customer wants a tsp head, we will sell it to them! If they want a full rundown comparison of comparable heads, they will get that also! We aim to please and to inform to the best of our ability.