Which heads for this combo?
Thread Starter
Pro
Joined: Jun 2015
Posts: 551
Likes: 102
From: Madison WI
Which heads for this combo?
Please share your thoughts, experience, expertise, etc. I am open minded and want to cover as many angles as possible as I finish the final touches to my C5. 
My current setup:
Stock LS6 short block
FAST92 Intake & LS2 Throttle body (CNC ported)
MS4 Texas Speed cam w/ valve train
Long tubes w/o cats
LS7 clutch
HP Tuners (tuned by myself, WOT will be hired dyno tune)
It is time to finally pick a set of heads to go with this combo and finish it off. Texas Speed recommended these two options:
227cc: http://www.texas-speed.com/p-1163-pr...der-heads.aspx
225cc: http://www.texas-speed.com/p-3515-pr...ral-heads.aspx
Biggest concern is valve clearance but was told by Texas Speed if I go with the stock size chambers (62cc) it should be fine.
Now for the details... I drive this C5 basically daily (35k miles w/ MS4) and enjoy it. I tune it myself and the FAST92 & TB have helped smooth things out which was nice.
I am hoping to get close to 500rwhp N/A - probably end up just shy but I don't want to go conservative. I went with FAST92 instead of 102 because Texas Speed said there wasn't much to gain without more displacement considering the extra cost of fuel rails and TB. Plus the 92 gives a bit more low end torque which helps with the MS4 cam.
My current setup:
Stock LS6 short block
FAST92 Intake & LS2 Throttle body (CNC ported)
MS4 Texas Speed cam w/ valve train
Long tubes w/o cats
LS7 clutch
HP Tuners (tuned by myself, WOT will be hired dyno tune)
It is time to finally pick a set of heads to go with this combo and finish it off. Texas Speed recommended these two options:
227cc: http://www.texas-speed.com/p-1163-pr...der-heads.aspx
225cc: http://www.texas-speed.com/p-3515-pr...ral-heads.aspx
Biggest concern is valve clearance but was told by Texas Speed if I go with the stock size chambers (62cc) it should be fine.
Now for the details... I drive this C5 basically daily (35k miles w/ MS4) and enjoy it. I tune it myself and the FAST92 & TB have helped smooth things out which was nice.
I am hoping to get close to 500rwhp N/A - probably end up just shy but I don't want to go conservative. I went with FAST92 instead of 102 because Texas Speed said there wasn't much to gain without more displacement considering the extra cost of fuel rails and TB. Plus the 92 gives a bit more low end torque which helps with the MS4 cam.
Pro
Joined: Dec 2015
Posts: 661
Likes: 182
From: Knoxville TN
If your wanting 500whp you can’t cut corners and have to pay attention to detail it’s the small things that add up
I would skip the tsp heads and go with something like a tea ported tfs 215, your going to need compression and going to have to flycut to get every last hp, if you have 93 octane then would do 58-59cc with .040 head gasket, pm valve guides
you would be better off with the fast 102 over the 92, low end tq will be a non issue with heads and more compression since it will raise it across the board, if your using the ls7 flywheel then it’s heavier and will cost a few hp, ls2 throttle body is fine, good luck in your build!
I would skip the tsp heads and go with something like a tea ported tfs 215, your going to need compression and going to have to flycut to get every last hp, if you have 93 octane then would do 58-59cc with .040 head gasket, pm valve guides
you would be better off with the fast 102 over the 92, low end tq will be a non issue with heads and more compression since it will raise it across the board, if your using the ls7 flywheel then it’s heavier and will cost a few hp, ls2 throttle body is fine, good luck in your build!
Race Director
Joined: Sep 2005
Posts: 11,060
Likes: 291
From: Pasco WA
Another vote for Trickflow based heads. Get them from Brian Tooley Racing, and he'll give you the proper advice to achieve your goals. Mine made 483/432 SAE with only a 228/232 cam several years ago. 61cc heads and 92 octane with zero KR. I had mine tuned by Wong's Performance. Brian worked at TEA at the time, and was very helpful.
Thread Starter
Pro
Joined: Jun 2015
Posts: 551
Likes: 102
From: Madison WI
Going to give Brian Tooley Racing a call today and see what they have to say. I really prefer not to fly cut the pistons, that may land me in the 480-490ish HP range but I can live with that.
Thanks for the advice so far
Thanks for the advice so far
Thread Starter
Pro
Joined: Jun 2015
Posts: 551
Likes: 102
From: Madison WI
So BTR recommended their TEA heads in 64cc size to match 243 head size and avoid fly cutting.
215cc: https://www.briantooleyracing.com/tf...ads-33098.html
225cc: https://www.briantooleyracing.com/tf...der-heads.html
They said if I had 430rwhp before the FAST92 & TB that the 225cc heads would put me pretty close to 500rwhp.
Also recommended their valve blending job ($75), 50* exhaust valve job, and the PM guides ($80) to get the most out of the those heads.
They asked if I was willing to swap the MS4 cam but they were not sure if stepping down on the cam and going smaller combustion size to get more CR if it would make up the difference and come out ahead enough to make it worth it.
I took another look at fly cutting but I don't have anyone local who could do it and taking the pistons out seems like I am again getting into the area where the HP per $ is getting pretty expensive.
I guess its pretty clear I am fine with 490whp vs 500whp
215cc: https://www.briantooleyracing.com/tf...ads-33098.html
225cc: https://www.briantooleyracing.com/tf...der-heads.html
They said if I had 430rwhp before the FAST92 & TB that the 225cc heads would put me pretty close to 500rwhp.
Also recommended their valve blending job ($75), 50* exhaust valve job, and the PM guides ($80) to get the most out of the those heads.
They asked if I was willing to swap the MS4 cam but they were not sure if stepping down on the cam and going smaller combustion size to get more CR if it would make up the difference and come out ahead enough to make it worth it.
I took another look at fly cutting but I don't have anyone local who could do it and taking the pistons out seems like I am again getting into the area where the HP per $ is getting pretty expensive.
I guess its pretty clear I am fine with 490whp vs 500whp
Race Director
Joined: Sep 2005
Posts: 11,060
Likes: 291
From: Pasco WA
Yeah with that big ol' donkey dick cam, it's a tight squeeze for 243 based heads. The TFs give you a smidge more clearance because they use a different valve angle, but If you're happy with the drivability you can just keep that MS4. I'll bet it sure sounds badass at idle. 
If it were me; I'd switch cams to one Brian recommends. Also, get the bowls blended, which is what he did on my 215s. I don't think the 225s are really superior with stock displacement, but my experience is almost a decade old.
Just remembered something... I home ported my FAST 90 with instructions I found on the forum, and I also had a %25 UD pulley, and an electric water pump, which could all have contributed to my numbers with a fairly small cam.
If it were me; I'd switch cams to one Brian recommends. Also, get the bowls blended, which is what he did on my 215s. I don't think the 225s are really superior with stock displacement, but my experience is almost a decade old.
Just remembered something... I home ported my FAST 90 with instructions I found on the forum, and I also had a %25 UD pulley, and an electric water pump, which could all have contributed to my numbers with a fairly small cam.
Last edited by zeevette; Mar 19, 2018 at 04:57 PM.
Thread Starter
Pro
Joined: Jun 2015
Posts: 551
Likes: 102
From: Madison WI
Yeah the idle turns a lot of heads and I get a lot of comments. Here is a short video:
It does drive pretty well once the tune is dialed in really well, mail order tune wasn't close and a $500 pro dyno tune didn't do much better - learned to tune myself and spent the time tuning and made a world of difference.
I am considering the 25%UD - stock pulley could use replacing before it fails anyways.
It does drive pretty well once the tune is dialed in really well, mail order tune wasn't close and a $500 pro dyno tune didn't do much better - learned to tune myself and spent the time tuning and made a world of difference.
I am considering the 25%UD - stock pulley could use replacing before it fails anyways.
