BEFORE ANYONE FLAMES ME...
I did a search but to many returns came back.

I was looking to purchase a base manifold later, but I wanted to know which one has more "meat" for me to port. TPIS, Accel, Edelbrock, etc.

TIA

 

I dont know for sure, but I think that they are all very close. Any will do. If I had to pick one, I would go with the TPIS manifold.

 

Well, consideirng that they are all the same casting...

 

Buy the cheapest one, they're all the same.

 

I went home and was reading about that TPIS manifold in the TPIS catalog. Apperantly it is hand ported to stock size. It says that gains up 22hp can be seem with porting. Well duh, why would you want stock and then port it out, I can do that at home. I guess that I will purchase the cheapest one, anybody know of any "group purchases" or cheap places to get one that is larger than stock?

TIA

 

Ask this question here and everybody will tell you they're exactly the same. Ask this on the corvette forum and you'll get a very different answer. Over there there are guys that have flowed them and found that the TPIS is simply a ported Edelbrock, and that that the accel flows as well as the TPIS and outflows the Edelbrock. It's also generally agreed that the Accel has the most meat for additional porting.

I don't have access to all 3, so I have no direct opinion, but I simply wanted to comment that you may want to search the Corvette forum, because a lot of those guys have flowed them and have some very different results than all of the visual inspectors over here.

 

Thanks, I will.

 

You know what. Jim's right. For some reason i was thinking that someone had offerered proof on all 3 being the same, but it was just dementia creeping in on me. I just did a few quick searches and found a couple of the posts i was thinking of to verify. The TPIS base is the same casting as edelcrock, but the accel is it's own animal.

 

A little secret: Edelbrock casts all of the TPI bases- TPIS, Accel... All they do is put a different name on the casting and sell it to whoever is going to resell it as their own. I used to be one of the engineers there. Given Edelbrock's production capability, these companies found it more economical to buy it from them rather than manufacture their own.

BTW, they also cast Scoggin-Dickey's Vortec TPI base- I designed it for them. When combined with Vortec heads it really does blow the conventional TPI/iron head or even TPI/Vette head combos out of the water.

The old TPI bases were made by porting a factory manifold and then pulling mold plugs out of those ports for reproduction in the new casting. However, for manufacturability, the pattern maker had to add draft and other features which, unfortunately takes a little bit away from the original design. The new Vortec manifold was designed in the 3D CAD software, Pro-Engineer, and included all of the manufacturing features in it. It then went through testing and production with no further alterations- so nothing was compromised. Together with the inherently better Vortec port design, the manifold is quite a bit improved over the previous generation.

 

Please tell that to the foundry in Ohio that is casting the Accel bases. I'm sure they would be interested in knowing that they are part of Edelbrock. This isn't meant to flame you, but the Accel bases are NOT cast by Edelbrock.

 

I guess they changed.

This was about 4-5 years ago when I noticed Accel and TPIS logos on TPI bases in the machine shop. I was suprised because I hadn't know that was the case until then. Who knows, maybe TPIS is even casting them somewhere else now? I left Edelbrock a few years ago, so I may not be completely up to date.

Hey, when I'm wrong, I'm wrong! ;-)

 

Is it possible that Edelbrock just had those bases there for testing?

 

Well whatever is right...

Thanks for everyones post, I ordered the TPIS because it was cheaper. Wow, I never thought that I would have said that aobut TPIS!! Anyway, I will port and match it to the ported SuperRam runners.

THANKS