Many times this has been asked. What intake manifold do you all think is the better of the three that I know of. Accel/LPE,TPIs or Edelbrock? I think that I heard somewhere that the TPIs Big Mouth and the Edelbrock are the same intakes but modded. Which one is better in your opinion?
Same goes for the AFPR. Which is best for clearance of the plenum? Adjustablity? Longivity?

 

opinions if you will.

 

As for the intakes, I think they are all the same, wait, they have different names in vary in price like $150, so they must be different!!! I would get the edelbrock unless a used one is found for less. As for the AFPR, I used a Holley for a while, it worked so I was happy. Again, there are like 10 diff ones on the market all the same, all diff prices depending on whose name is on it. As you may well imagine, the aftermaket namebrands don't impress me much!!!

 

On the intakes I might say yes, but the AFPR there has to be a difference. The BBK doesn't wprk for some people. Some have the clearance issue. Stuff like that. From what I hear the Holley one is the better one of all the AFPR's. Still don't know which intake is the better one of the big three. I know the TPIs and Edle are the same only ported or so but I wonder about the LPE/Accel one.

 

With the intakes, I would bet real money that you can't notice a difference between the three. Well maybe in your pocket!!! They all market them to work with stock runners and stock equipment so that limits the range of what they can "engineer" into it.

Yeah, I remember reading, now that you mention it, about some clearance issures some have had with AFPR and the upper plenum. I think most of the guys just filled the adjustment bolt some or dimpled their plenum. I don't know, I was lucky I guess, mine was a true "bolt on"...

 

And what AFPR was that? I need a AFPR now that I have a bigger cam and some heads. Been thinking about the FASTInjection too. $999 I could see myself buying that thing!

 

I am not going to try to talk you out of an aftermarket computer, great devices, but I have a great fondness for tuning PROMs instead. My list of pluses are cheaper, requires lots of learning and experimention to get used to, and I think more rewarding in the long run. Now, if I had the money to lay down for an aftermarket computer, I would probably go that route, but then again, I like be able to tell people I tune my own chips. I guess it all comes to preference with that one.

I used to run the Holley AFPR when I still had TPI, now I have an HSR, Holley Stealth Ram in case you are not familar with it...

Talk later, I going to bed!!!!

 

I meant the TPI style First stuff. I want a new chip but no means of doing it myself.

 

The Holley AFPR offers the best clearance issues of the adjustable type, mainly because instead of a bolt coming out the top the entire top plate is rotatable for adjustment. This by does not mean you won't have clearance issues. I had a problem with mine had to grind the rear plenum slightly. I also adjusted the **** in a bit to make it fit. Still operates within the range I need but it limited me on how far I can thread it out. Also there are about three different plenum designs depending on year, some people had no issues. I think also if you are running aftermarket runners the heights these place your plenum at may vary just slightly. So go Holley best chance, worst case scenario you have to do some grinding to make it fit as many of us had to.

On the intake it really doesn't matter which one you buy. Go with the Edelbrock based on price. I can say this do not expect to buy any aftermarket base and not expect to need to port the openings. You can install them without doing it but you would be cheating yourself out of alot of money. The Edelbrock openings are stock size to match stock runners as stated in there advertising, the inner ports however are much larger and all that is required is grinding the openings to match your runners. I took all my ports to 1.75" and siamesed my plenum. Here is a pic of the difference between stock and ported aftermarket, keep in mind the only porting I did to the base was the openings.

Stock port:

 

Edelbrock ports:

 

I was wondering the same question. After researching, I came up with the following concusion: If a person already owns a stock base, it could be sent off and have it extruded and ported for around $460.00. If you bought a aftermarket like Edelbrock you would still have to have it ported. In the long run it seems to me that you would end up with the same product and possibly at a lesser cost. Although the aftermarket runners could be extruded and ported while the stock can't. The plentum can also be Extruded and ported. All in all, I believe this would be the way to go. Afterwards I plan on sending them off and have them Coated. If I'm wrong about this please let me know and explain why as that I like to understand why and what I'm doing.

Bill

 

In my opinion, the cheapest way to go about retaining TPI and having max. flow would be to siamese port your stock base and then buy some good runners and then port your plenum. Anyone with a die grinder and some time, provided they take the time to learn what has to be done can accomplish this task over the weekend. Granted, it may be a long weekend depending on how fast you work, but it could be done. Then really the only expenses you would have would be the runners and a gasket set. If you already own a die grinder and the appropriate burs and sanding cylinders. I assume most of us have a die grinder of some sort because who hasn't had to manipulate something into place...

 

First the term extruded typically refers to the manufacutring process. An extrusion is something formed by pressing material through a die to create a certain shape. Think of the Play-Doh kits as kids when we would stick a ball of dough into one of those gimmicks that you would pull a handle and the play doh would come out in shapes or look like spaghetti. Thats extruding as I know it. Unless your talking of extrude-honing thats a different thing. Which is just polishing up and taking out the imperfections of a casting or extrusion.

As far as porting, look closer at the two pictures above notice that on the stock base theres just no material there to port out to match the Edelbrock unit. You have to start with a thicker casting to allow you to make your ports larger. There is no way to get the same flow from the stock base as can be achieved from an aftermarket base.

 

Yes, I was refering to extrude-honing. My understanding is it also "opens up" the area too. I checked your pics out again. I thought they were before and after After reading your last post I rechecked the pics. I clearly see your point. I noticed the golf ball, was that used as a sort of guide to determine the size? Also would the Edelbrocks need to be Siamesed as well or just ported?

I've ported heads before, so I wouldn't have a problem doing the porting myself.

One last question. The TPI unit I have is a 85 w/ cold start valve. since I'll be doing away with that Shouldn't I be able to go to the later style Edelbrock base & runners and still use the stock 85 plentum?

Looking at everything it seems that porting the Edelbrock base/runners and the stock plentum would be the best way to go.

Thanks for the info, I'm greatful
Bill

 

When you say will the Edelbrock need siamesing, are you refering to the base, I wouldn't do that. Some claim to siamese there stock bases for more flow. I don't know about this practice not sure theres any gains and quite possibly some problems. After all this is a "Tuned Port Engine" Siamesing basically takes out the ports and creates a larger opening. Ok to do a bit up at the plenum and top of runners (this basically enlarges the volume of air in the plenum, and shortens the runner length).

As far as dropping your cold start, physically yes you could bolt that together. I just can't remember off the top of my head what effect it will have on the rest of your system. The cold start is there because the injectors do not fire immediatly on our cars. You may end up with a tough starting problem unless you also changed the parameters of your ECM so it wasn't trying to utilize the cold start injector. There is a switch on teh intake manifold up front right next to your CTS. This switch tells the ECM to fire the cold start. You would probably have to do something with this also. Start another post with that specific question. You will get replies from people who have direct knowledge of this process, I can't help much because I never messed with it.

 

Thanks for the info. Wasn't sure about the base, some were talking about siamesing the base and I wasn't sure if they were including the aftermarket stuff.

Should have mentioned, as this is a retro, I'll be using a SD 730 or another type of ECM/PCM which doesn't use a cold start valve. I was wondering if the different styles would bolt together. And you answered that.

Thats again for the info!!!
Bill