NighTrain66....Im going to really try to get a hold of GTP than. I did spend a good chunck of change and a little intake port work would be all that I need....Ill report back as to what happens.

Ill try and get those numbers. Bret and I didnt talk about the numbers at length but Im pretty sure he mentioned the low and mid numbers were pretty decent.

 

If the #'s are

.200---130-135 or better
.300---190-195 or better
.400---230-235 or better
.500---250-255 or better

you might consider running em like they are.

This is of coarse MY opinion, Chuck or Phil may have some more #'s for you to use. You may want the #'s a lil higher than these but at these #'s you may niot have to go back through em.

NightTrain66

 

I think that once you get ahold of honest numbers, you really need to compare the entire flow range, and not just a peak number. Use the RMRE method Chuck posted earlier, it's quick and works well.

Using the AFR 195 LT4 "Competition" CNC port numbers on Nutek's site, and comparing it to a good handported LT1 head will show that a few people can actually make the LT1 outperform the big bad competition cnc LT4 by a sizeable margin. Who woulda' thunk

I like to see 200+ at .300 but anything over 190 is usually better than what most get. At .400" I'd want it over 240, and over 265 by .500.

I see the mention that the 21Xcfm exhaust may "make up for it".. and unfortunately, IMO that's incorrect. A terrible exhaust/intake ratio (at peak numbers anyway) out of a mediocre intake and gigantic exhaust is going to do anything but help you. Compare your huge exhaust flow numbers to a good exh that peaks in the 190's using the aforementioned area under the curve formula, I think you'll be surprised.

Good luck with it .

 

Thanks for the advice...you learn something new everyday. Ill defenitly post back...

 

Matt,

Your flow numbers are: (to kill 2 birds with one stone)

Exh w/ pipe (1st) and w/o pipe (2nd)

.100 75 70 70
.200 135 125 125
.300 189 180 173
.400 231 202 186
.500 258 212 192
.600 258 217 196
.650 252 217 196

The intake runners were 187cc
The exhaust runners were 71cc (I think that is from memory)
The cambers were 51-52cc

These heads along with your new cam on 3838 LT1 should be worth 480-500hp @ the flywheel, a better flowing intake would be worth 20more, and better heads (275cfm) would be worth another 10-15more.

SkarodoM,

I like the numbers your heads do. I'm also one of those guys who likes high exh flow, especially on a SBC (23 deg) head. It let mes use less exhaust duration and make more low end TQ and run a narrower LSA. I would rather use a 80%+ E/I % then one below 75%, then again I like to run big headers and still make more TQ than most guys.

BTW guys here is another set of heads from GTP,

exh w/o pipe

.100 81 74
.200 147 125
.300 198 160
.400 237 180
.500 258 183
.600 258 183

Couldn't get a volume on these heads because the seats on these heads are so shot they could not even hold solvent to cc the runners and chambers, even after I greased them up. After I get the seats and valve job done I will check them.

After seeing these numbers and the amount that these heads were purchased for I was shocked! A place that I recomend has numbers very similar to SkaradoM's numbers and are only slightly bigger in volume (but not too much) They also have very good exhaust numbers and they are cheap too. (BTW I am going to become a distributor for them soon, because I like the pricing/flow from their heads so much)

One other thing I noticed is that the valve seat and valve job that GTP uses does not last very long, that is something I hate to see. Durability is something I look for out of a valve seat so you can run some good spring pressure.

Bret

 

NightTrain66 from what you posted it looks like my heads fit your criteria so I guess they could be worse.....

Thanks Bret, I might look into those heads your talking about, Ill email you though.

 

Just for a little comparison, here are the flow numbers from my stage 3 TEA heads. The exhaust side was flowed with a pipe:

lift----intake----exhaust

.100----70.2----56.8
.200---149.7---115.0
.300---209.5---164.4
.400---250.9---201.5
.500---268.1---227.5
.550---270.4---239.8
.600---276.1---246.0



Nick

 

If you know some one that can do a cheep clean up on the heads ($100-$200) and get ya closer to Skarodoms #'s than it may be worth it. The #'s I posted are considering the peak of 258 at .600 lift is all I had as far as info on your heads. If they peak there than The #'s I posted were my guess on what the other #'s should look like. I agree with Skarodom on the better #'s at all lift points but already knowing the peak #'s I threw the other #'s out there for you to compare to and if yours were below these I would have em touched up for sure.

If you had stock heads on before and are going with these than you will be happy with the performance of the car and SOTP feel. If you are just after a lil more power than just bolt em on, If you are after a certain ET improvement or a certain dyno # than you may not be happy with the gains and therefore you might want to have em "cleaned up". It would probably consist of raising the roof a lil and straightening the long wall, widening the shortside a lil and slicking it all up. If you can help the .300 #'s maybe 5 cfm, the .400 #'s by 8-10 cfm, the .500 #'s by 10-15 cfm and the .600 #'s by 10-15 cfm for a $200 or so than it may be worth it. I doubt if you can do anything with the .200 or below #'s since the valve job has been done and any attept may result sinking the valve (hurting flow) and more $ for a new valve job.

It would be interesting to get the TEA head flowed on Stroker's bench and see compare them to the TEA #'s an dthe GTP #'s from that bench. TEA must use some kinda BAD *** pipe on the exhaust.

NightTrain66