dohc

I would say epoxy the Fast ports and shape it to match.

I wouldn't call it a band-aid at all. There is epoxy specifically design to go into intake ports. Port epoxy was designed to add material to intake ports where needed. Back in the sixties, thats how GM refined there port shapes (tech. book I read that in was printed in the 70's). Probably still do today (along with computer aided design). Once someone comes up with some epoxy that will standup in the exhaust port, then we'll probably see the OE's using it during developement (right now only welding in material seems to work).

Also, most of the air flow in a port actually follows the floor. Heavier fuel vapour tends to follow the roof more. In a design where the injector is aimed at the intake valve (like most passenger cars) the roof of the port is less important then the floor.

A carbed motor, TPI, or a high rpm motor (where the injectors are a further upstream of the valve) the roof of the ports need more consideration.

Sean Collins

Well the Fast port is to big for even a fully ported stock head on most apps. Tough to just port match them without epoxy.

As for you unique problem it looks like the head have been milled a good 30-50 thousandths. As you mill the heads they move father away lowering the port floor creating misteps and alignment issues. you only resolution is to epoxy the port and match or send the heads back the TSP and have them weld the decks up and put them at the stock chamber volume and or replace the overmilld heads. Classic SBC problem.

redtail2426

iTrader: (10)

the epoxy thing is exactly as you say,a sixties and seventies thing.In this day and age with such precise machining capabilities,there should be no need for any epoxy fixes,especially on a set of cylinder heads that cost 1800 and change..And His heads being milled helped his problem,didnt make it worse..The intake port on the head is to high,and milling will move it down,to create a better match.On the classic small blocks milling the heads will make the intake ports on the heads lower then the manifold ports,but thats not the case here...I know Edelbrock designed these heads, and they did a **** poor job,plain and simple.Just look at the shape at the bottom of head ports and intake ports.As you can clearly see the manifold ports are mostly squared off as they should be,thats how all ls1,ls6 manifolds and head ports have always been.But the designer of these $1800 heads decided to make the bottom of his ports rounded,not just a little rounded,but a full round,as you can see in the pics above.Just a plain and simple poorly designed cylinder head..

I dont mean to sound like a dick,i just hate to see people spend that kind of money for a product and have fitment issues as bad as this one,its just not fair and the customer should be the one who gets the shaft..I really hope they take care of this problem for this guy and he ends up happy.

Sean Collins

do me a favor mill a junk head and see what happens. The deck is to thin now. when you mill the heads the heads move away from the intake. As the heads get farther away they manifold they sit lower on the ports becuase the wedge of cheese your trying to stuff in there is the same width but the hole thats there to fill is wider. On a SBC usually you have to mill down the china wall surface on the intake to get the intake manifold closer to the port and then you have to face cut the intake and report match the floor of the head in extreme cases.

Is the head on the block ??? i wouldn;t check fit without it being on the block with a gasket on the manifold. The mismatch most likely isn;t that bad. I don;t think TSP is welding up the lower portion of the intake runner.

N4cer

iTrader: (11)

That's the original port design. And honestly, it probably won't matter much. But I can't see any customer being okay with that, and I would expect to be warned ahead of time when purchasing them. That's not a little something that you just ignore. But being on the bottom, it probably isn't as bad as we're making it out to be. Just too nasty looking to sell.

What did the guys at TSP have to say? Are they on vacation? They're usually pretty quick to respond to threads about their products.

prplhaz

Is this an issue w/ any other aftermarket heads?

vader99

iTrader: (4)

Any news on this yet? Some sales of these heads might be lost soon if there is no good resolution to this issue. I might have to go back to the AFR heads as my first choice once again.

redtail2426

iTrader: (10)

all i was saying is that milling didnt make this guys problem worse then it would have been if he didnt mill.

1LSWON

iTrader: (8)

Well man you get what you pay for and imo 1800.00 is on the cheap side for heads. I'm sure you will get it worked out though.


Thomas

S1LV3R

iTrader: (5)

If TSP buys the "porters versions" and runs their own program on them, how can you blame Edelbrock?

redtail2426

iTrader: (10)

.I am pretty sure you are right on that,i just looked at the tsp website and it sayd there built off of an edelbrock casting.So yeah i was wrong blaming edelbrock,TSP is the one that needs to chime in here.

dohc

I agree, I don't like the port shape either. I was actually considering these heads, but now they aren't even in the running.

Anyway, working as an engineer, I wear several hats. As a consumer I would be pissed too, but as an engineer, I can't come up with a design that will satisfy every possible combination out there. The head was probably designed to work with a stock manifold. All I'm saying is sometimes the customers need to be prepared to do modifications for their particular combination.

Also, since milling a head on a 90 degree V engine doesn't just lower the ports, it moves them toward the centre of the block. At some point, the intake mani bolt holes won't line up anymore

Epoxy is still a valid fix for mismatched parts. Unless an intake, exhaust, and head were designed at a package, your always gonna have problems like this.

Jason 98 TA

iTrader: (4)

Guys that port has been dyno tested time & time again. The dyno results speak for themselves...

I've discussed the mismatch that occurs with the fast intake with the porter & he will be tweaking the small runner port to help eliminate this lip at the bottom of the port. While I'm not sure it will change power output any, I will still be updating the port so it will be more fast intake friendly.

vader99

iTrader: (4)

So, by your comment, do the intake ports on these heads line up better with the ls6 intake than the fast?

caseys103

I just happen to know the guy that designed that port. For those concerned with the large radiuses in the floor I will have you know that is the same radius size found on AFR and ET performance cylinder heads, It looks rounder because the entrance in narrow. That port was designed to have a slight mismatch at the floor with a stock mainfold, The degree of mismatch on the FAST I would agree is excessive but really not any problem to correct. A small amount of epoxy could be used or the port could be gasket matched. As Jason stated the port will be adapted to line up better with the FAST intake. Which in reality takes a few minutes of port work then the head (original) just has to be re-digitized. BTW the difference in power will be minimal. Just so everone knows how I feel about that head..I believe it is among the finest heads you can buy. There is technology in the port designs (and chamber)that has proven to make big power.

Casey Snyder
Cylinder Head Instructor
School of Automotive Machinists

caseys103

If you guys think I am biased, well your right.

WeathermanShawn

iTrader: (1)

Running TSP 200cc Heads for two months. On LS6 Intake.

Zero problems. Great on dyno, great on street. Very pleased.
Hitting 400TQ by 3500rpm's.

Can't address Fast 90/90 situation...just letting you know, working good out here in Mile High Country..on LS6 Intake..

N4cer

iTrader: (11)

Link to your graph, please.

Mcduffys

iTrader: (2)

Casey and Jason

I happen to be helping lilbuddy with this project and have a couple questions?
Is it neccessary to use epoxy and build the FAST up to the intake ports on the heads? or will it be fine leaving it as shown in the picture ?

Also being that the FAST intake ports match up pretty well to the intake ports on the head as it sit. Would there be any gain port matching the FAST intake ports to the heads ?

Thanks for your help.

caseys103

There are several way you could go about that project. I know several people on this thread were opposed to the use of epoxy.But, I have successfully used Z-Spar 788 Splash Zone (green death) epoxy for years. If it were me that is what I would do. Or you can gasket Match the heads to fit the manifold. I would be glad to help in either case.