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decipha
11-08-2009, 02:39 AM
here are pics of the heads off my 91 titanium auto supercoupe

the engine was overheated big time, all 3 cylinders were blown on the driver side and cylinders 2 & 3 were blown on the driver side, so effectively it was a 1 cylinder lol but it was so warped that I had to shave 15 thousandths off just to get her flat again

anyway, i pulled the heads with the intentions of just resurfacing them and slapping on mls gaskets....

well after i was done sand blasting them and cleaning them up good, i pressure checked the valves and all 12 were leaking BADLY.

So i started disassembling them, when i pulled the first valve i checked the guide and it was so loose that I had about 20 thousandths worth of play :eek: Needless to say all of the guides were worn extensively.

so since it needed to be sleeved i figured i might as well go with larger valves. Well it didn't stop there, once the valves were done it just didn't make sense not to port the heads ;)

so heres the final outcome. They haven't been flowed yet but i know it flows alot better than before, hoping to use a friends flow bench to find out the truth.

http://c4.ac-images.myspacecdn.com/images02/95/l_7ea07528547e4fd68449dbb9ce58f91f.jpg

http://c1.ac-images.myspacecdn.com/images02/101/l_e82bfbbbe2af49f98accb8e7b761fc48.jpg

http://c3.ac-images.myspacecdn.com/images02/48/l_3e7bd260b76f4b2fb75357c4251725ba.jpg

http://c1.ac-images.myspacecdn.com/images02/95/l_fde6f9fc3af9456e917c0b548b7ac244.jpg

http://c3.ac-images.myspacecdn.com/images02/93/l_a5558d4244444344b7bdbca4c7d0b58e.jpg

http://c3.ac-images.myspacecdn.com/images02/45/l_c648381ac9de4d13922ee0f97a63d416.jpg

http://c4.ac-images.myspacecdn.com/images02/9/l_e7c1d81c1bac4314afdedfd0064f1723.jpg

http://c1.ac-images.myspacecdn.com/images02/58/l_47550e1e71ab4448aef607d6dcd5afe4.jpg

http://c2.ac-images.myspacecdn.com/images02/64/l_107c225c0b00460dbd46f8fe8be63d7d.jpg

http://c4.ac-images.myspacecdn.com/images02/5/l_e201f9a1c6bf408994984e0c0e2fa2ef.jpg

anyway my main point was that if this combo does prove to give some substantial gains there just may be a few more sets done

but first i want to see what kind of power these things make, i may throw them on my bone stock 94 5spd and throw it on the dyno, its completely unmolested so it would be a great test specimen. However unfortunately I do not have any prior dyno pulls from the car so it wouldn't be quite exact but enough to get an idea.

if anyones interested shoot me a PM

NEEDaSCbad
11-08-2009, 03:40 AM
Pm sent......

thirdbird
11-08-2009, 02:56 PM
Those exhaust ports look fantastic! (all parts of those heads do:))
That's what I shot for with my porting. I see the bump and a slight radius like in my own.
Nice.

decipha
11-13-2009, 09:14 PM
what you see there is whats known as a 5 angle valve job

scxr7
11-15-2009, 04:25 PM
price please

decipha
11-15-2009, 10:59 PM
no idea as of yet since these heads still haven't been flowed, we've been slammed at the machine shop so as the saying goes... work before play

decipha
11-26-2009, 01:15 AM
dropped the heads off to get flowed... awaiting the results, I'll post back with the numbers

scxr7
11-26-2009, 11:36 AM
If you decide to do more heads and keep the price competative I'll take a set. how large are the valves you plan to put in those heads?

rbrown
11-28-2009, 11:54 AM
Awaiting the flow numbers.

David Neibert
11-28-2009, 10:57 PM
What size valves are you using ?

David

thirdbird
11-28-2009, 11:39 PM
what you see there is whats known as a 5 angle valve job

5 angle is overkill IMO...

dcjrcode1
12-04-2009, 02:44 PM
any idea of a price yet, flow numbers and what valve sizes are

decipha
12-04-2009, 08:55 PM
these are the gm valves which are recommended around here to be the ideal large valve replacement

the heads have been flowed and showed nice improvements at .1-.4 lift but maxed out at .5 and didn't flow any more at .6

this is on par because the intake side was barely kissed, we wanted to flow it first to have something to compare to, the exhaust side was cleaned up so we expect the exhaust to show big improvements, won't know until the exhaust is flowed, hoping to have those results within the next week.


im currently talking with dave dalke to get his insight. I'll post back with my findings.

overall i'm very excited with the results, im hoping we can get some more done to it and send them off to dave dalke for his approval.

shall see soon but i want everyone to remember, this is all being done after hours when we get free time. Once there done and the gains are known these will become the template and we'll be doing many sets of them.

stay tuned :cool:

scxr7
12-04-2009, 10:48 PM
hells yeah.

decipha
12-05-2009, 08:14 PM
gm 305 intake valve
intake - 1.84
exhaust 1.56

actual flow numbers from bench non ported just big valves
.100 - 69.3 +26% :eek:
.200 - 122 +24%
.300 - 161 +23%
.400 - 182 +13% :(
.500 - 189 +9% :mad:
.600 - 189 +4% :confused:

stock
.100 - 55
.200 - 98
.300 - 130
.400 - 160
.500 - 172
.600 - 181

typical big valve
.100 - 58
.200 - 108
.300 - 156
.400 - 192
.500 - 208
.600 - 204

ported big valve
.100 - 68
.200 - 130
.300 - 177
.400 - 208
.500 - 211
.600 - 215

rbrown
12-05-2009, 08:24 PM
These are intake numbers?

decipha
12-06-2009, 02:08 PM
yes sir we flowed the intake, the top numbers are the exact numbers from the flow bench

the remaining numbers and scenarios were given to me by dave dalke

rbrown
12-06-2009, 04:09 PM
K. Thanks.
Would like to see those exhaust numbers.

I have a set of heads on the floor that have been worked and would like to see comparisons.
I also have a set I have to pull that I am going to have flowed to see what someone elses work did.

decipha
12-06-2009, 11:35 PM
sounds like a plan i have to commandeer a set of stock sc exhaust manifolds to flow the exhaust side though

don't know where im going to source any just yet

rbrown
12-07-2009, 12:04 AM
sounds like a plan i have to commandeer a set of stock sc exhaust manifolds to flow the exhaust side though

don't know where im going to source any just yet

Why? Most flow them through a pipe attached. Straightens out the flow and gets a better flow number. Is standard practice.

decipha
12-09-2009, 12:32 AM
but thats not accurate, im sure that would look good on paper but just not practical in real world use

dropped off a stock manifold today, lead machinist at the speed shop is going to be at the annual swap meet in Florida till next weekend.

so doesn't look like anything is going to get done.

rbrown
12-09-2009, 01:16 AM
but thats not accurate, im sure that would look good on paper but just not practical in real world use

dropped off a stock manifold today, lead machinist at the speed shop is going to be at the annual swap meet in Florida till next weekend.

so doesn't look like anything is going to get done.

So you're saying those intake numbers are with the intake manifold on?

rbrown
03-04-2010, 10:38 AM
Did we ever get exhaust numbers?

90blkbrd
03-04-2010, 12:43 PM
Has these heads been field tested yet?

decipha
03-05-2010, 01:40 AM
lol no the heads were flowed without the intake manifold mated to it, i figured using a stock exhaust manifold would be ideal for repeatability purposes, since not everyone uses the same length or diameter pipe, that way anyone that gets heads flowed could compare there's to these directly and it would be a very practical comparison since you have a standard for reference, may be overkill but I figured, why not?

no the exhaust was never flowed, after come consideration we decided against this setup because the valve-train weight was so great.


we discovered by punching in some new guides using the 7mm GM 5.3 valves and ls6 springs were able to cut down the weight significantly, this is a HUGE improvement over the gm 305 valves. A weight savings of 28 grams (approx 1 ounce) :eek: You don't even have to know what an engine is to figure out that's a huge difference and will dramatically improve engine response.


Using the ls6 springs with these valves increases the seat pressure from stock 80# to 120#, when checking the 5.3 valves in the seats already cut on these OP heads for the 1.84 gm305 valves, it was a beautiful fit.

I talked to Dave earlier this week and he said this is the same setup that supersixmotorsports utilizes for their heads, I wish I would have known this before hand, oh well live and learn.

the new valve-train is on order awaiting arrival, once we get the heads back together we'll get them flowed again, this time the exhaust will be done as well, so only time will tell.

It seems like you 'gents are really interested, if i knew there was a market out there for some high performance heads that wouldn't break the bank im sure that would help streamline the process. ;)

anyone with a serious interest feel free to chime in and post your .02