TU or FWD ported exhaust manifold?

[xf69fs]

I am rebuilding my van and a 86 CS daytona for a friend. Hes funding me to build the car

Whats better? The TU or FWD manifold?

Ryan

[tryingbe]

They're not going to be that much difference between them.

[firebaron90]

I havent seen one of Cindy's, But i have one of MPG mikes, who I belive does them for TU. Very nice!

Joe

[johnturbotron]

I am running a Forward Motion ported manifold I think there all about the same.

[86Tona]

I have one of MPGMike's ported exhaust manifolds. The ONLY difference in what I got and what may be available (and I'm not 100% on this) is that mine is a custom.

I mean I told Mike that I didn't want 300HP but I did want around 200HP. The other thing that was important is my desire to increase economy. There IS a difference in porting when it comes to power and economy. The compromise is in the porting.

If you want to see the process of this porting job check out this link where Mike has published an article on my manifold.

Holler: Porting A Turbo Exhaust Manifold

[xf69fs]

Would spending the extra money for a 3 inch SV be worth it as well? Using the stock garret turbo, ported manifold, ic and some cleaning up on the head/gasket maching. Or use the stock 2.25 and go 3inch after that??

Ryan

[86Tona]

IMHO 3" is over kill. I plan to use a 2.5" system. If you checked the link there are links to the turbo rebuild he did for my car. The stock swing valve was opened up to about 2.5". This was perfect because of the plan for this engine. Since the actual outlet size is VERY much smaller than 3" and since the swing valve is shaped more or less like a horn, the opening at the pipe should be somewhat larger then the largest opening of the swing valve.

Check out that link and then click on the turbo link. In there he talks about the 'porting' of the swing valve and the wastegate opening as well as why he felt these were important.

[tkelly27]

No. 3" exhaust is a proven power maker over a 2.5" one, ported or not. Even if you're not after more power than a 3" will handle, it will spool up quicker.

[86Tona]

Quote:

Originally Posted by tkelly27 No. 3" exhaust is a proven power maker over a 2.5" one, ported or not. Even if you're not after more power than a 3" will handle, it will spool up quicker.

Yes but to what extent. The 2.5" will make power up to 250HP or so just like the 3" will. It sounds like with the mods he's doing he's not talking about trying to make this a killer power maker. After all he is using the '86 internals unless I missed a post. I don't think that the '86 internals would handle much more than 250 or so anyway so why bother with the larger pipe? The cost of the 3" swing valve just to be able to install 3" pipes would not necessarily be a good use of funds IMHO. But by simply opening the stock swing valve and using a 2.5" pipe will handle what this build will throw at it.

[tkelly27]

Well he's also asking about ported heads and custom intake manifolds, so he could very well be exceeding the limit of non-CB internals. Even if he's not, all the 3" setups I've heard sound better, there is a very noticeable deacrease in spool up time, and should he ever upgrade his internals and turbo, he'll be limited by his exhaust.

To go to 2.5" he's got to get a complete exhaust system, even if he ports the stock swing valve. Wasn't the 3" worth 15hp over the stocker? There were dyno charts, I forgot where they are.
*edit*
turbos
they claim 5hp over the 2.5" and more with the 2.25".

2.5' is a cheap and capeable alternative, but if you're you're not on a budget, go for the 3". There is also the middle of the road, 2.5" down pipe that bolts to the stock piece and then a 3" exhaust system. That's what I did with my van, wish I had had the $$ to go full 3" though

[xf69fs]

Well there is the 2.2 non cb in the car right now, condition, unkown. I may drop a 2.5 into it later cause they are easy to score from the vans. Everything I do to the 2.2 I want to be able to carry over to the 2.5 if there is a failure.

The car is a 86 CS daytona. The rods you say only do 250hp? Well we will see how much we can make...

Ryan

[xf69fs]

Well I jsut read the article about porting the stock SV. I always wondered about that. Looks like that will be my best option, cas I already have the stock SV.

Ryan

[glhman]

Quote:

Originally Posted by xf69fs Well I jsut read the article about porting the stock SV. I always wondered about that. Looks like that will be my best option, cas I already have the stock SV. Ryan

Dead thread, I know, but does anyone have a link to porting the SV?

[The Pope]

porting the SV is pointless. The gain is the volume, which doesn't change by any real %. HP is not real effected and unless you have a larger turbo your going to spool a stock 89 type Garret quikly without the 3" SV with a 3" DP.

Porting the exhaust manifold is a no brainer, match it to the turbine, the head gasket and open the hole between the turning and the #3 port. Then polish with sand paper roles, pretty easy. I like to go farther by sanding them at the head to flatten them, they get warped and don't seal as well. Then I like the 2,000 + degree ceramic to protect and reduce the heat on the outside.

[Ondonti]

Quote:

Originally Posted by firebaron90 I havent seen one of Cindy's, But i have one of MPG mikes, who I belive does them for TU. Very nice! Joe

No.
Moparzrulez does TU's manifolds.

I would say they are all pretty much the same though I know the individuals who make them would disgree and then say "blah blah flowbench numbers that I did on my own product"