Does anyone here have a Edelbrock intake manifold? if so what do you think of it? it seems to be one of the cheapest base's around for $355 bucks Thanks - Don

 

You'll find no differences between the Edelbrock, TPIS, and Accel lower intake manifolds. Only difference is price.

 

I'm not sure I agree. If you ask this question on corvetteforum.com, 99% of the guys will tell you that there is a significant difference between them. The TPIS is a ported edelbrock, where the accel base is a unique casting. The Accel base is supposed to flow just as well unported as the TPIS base flows (i.e. it flows as well as a ported edelbrock), and has plenty of room for additional porting.

If you give Rich at cruzinperformance.com a call, he'll give you a price on the accel that's not much more than the edelbrock. I bought some stuff from him and couldn't be happier.

I'd ask about the intakes on the corvette forum in the C4 tech section to see what they have to say.

 

If your planning on doing porting to the intake anyways it's sounds like your best with the edelbrock.

 

or port the accel and still be better off.

 

not to flame here, but they are all the same. I have had an accel, and an edelbrock. The Tpis big mouth is the same damn thing as the edelbrcok. The accel is the same in dimensions. Bang for buck is the edelbrock and the not the other high priced ones. I had my edelbrock ported and it flowed over 330cfm! If you want your intake ported e-mail me and we can talk 145.00 fully ported!

Drew

 

Very good point guys.

 

Not to flame here either but NOSFEDGTA, do you have actual documented flow figures to verify that the Accel is the same as the Edelbrock or are you simply going on dimensions? Dimensions don't mean anything to a flow bench. Did you also have your Accel manifold flow tested when you did the Edelbrock?

 

I had my edelbrock flowed, tpis, and the accell. Stock for stock the best flowing was the tpis by a few cfm "and I mean a few". But for the money it was not worth it. I had mine ported and matched to a super ram runner. Now lets look at another aspect. If you ahve nearly 300 cfm or more on an intake show me your cylinder heads that flow more>?< If your head flows more than 300 cfm then you should not be using a tpi anyway. Yes mine flowed 330, but that was not a goal it just happened that way. My head flowed 262 on the intake side. So I have enough air to supply the head and my intake was not a bottle neck. Another thing to look at here is port matching. If you port match everything from tb to the plenum-- the plenum to the runner-- the runner to the base-- the base to the head you will have the best results! for trial and error we did a friends and he gianed 4-5 ths in the 1/4 just port matching..

My 88 Trans am ws6 runs 3.92 all day with a one time dip to a 13.87 with the plenum matched to the runners, the walls in the plenum removed, the groove in the runners removed, a 2800 stall, flow master muffler, no air filter "at track only", no cat. That was done with a set of slicks, and oh ya 184k miles on it!

The most important thing to a car is enough air "for the motor"! and traction!

Drew

 

That's interesting. I bought both an Edelbrock and an Accel manifold and flow tested both. The Accel flowed 18cfm more right out of the box than the Edelbrock. I then "cleaned up" the Accel and picked up and additional 20cfm. I didn't bother doing anything with the Edelbrock and sent it back. Maybe it was just a "fluke" but in my test the Accel was better.
I agree on port matching and the "air for the motor". More doesn't necessarily mean faster if you don't need it or can't use it.

 

welcome to the world of casting flaws and the lackof quality control

Drew

 

where's the cheapest place to get an accel base from?? also i have a question, i bought a plennum off an 86 Iroc thats is polished i want to port it myself and get the SLP runners, would i benifit by putting this plennum and the SLP runners on my car with the stock base for now? BTW i already have the slp TB airfoil istalled Thanks -Don

 

Don, email Rich from Cruzin Perfomance for the best price on the accel base. I bought mine from him and he's a fantastic guy to deal with.

88, I've been told the same thing by the guys on the Corvette Forum. Those that have flow tested them have always found the accel to flow better.

 

SLP runners are ****. Dont waste your money. I dont care if you siamese the base and all that crap. Not worth the money. Im sure most people would agree. My car slowed down after putting them on. The first 2 passes were good but then it slowed down. The reason is heat soak! the do no cool as good. I swapped back to the stock runners and pickup my 2 tenths I lost with the slp's.

Drew

 

not that i dont belive you NOSFEDGTA but does anyone else have opinion's on SLP runners? i was really leaning toward them since they are just under $300 bucks in summit

 

Actually, most people don't agree. The SLP runners are by far the most popular runners on this site, and with a car that's upgraded properly, they won't slow you down. I doubt seriously that they have any sort of effect on the incoming air temperature. Sure, they are a thick casting, but the entire intake system gets right up to engine temp after a while anyway. If you port match your plenum to the runners and the runners to the base, you'll see noticable gains. Some of the Corvette guys have done dyno tests with just runner swaps with port-matched plenums and picked up 8-10 hp. With an accel base & slp runners, their average gains seemed to hover around 15-20hp.

 

Actually most corvett owners will tell you they suck. Have you ever heard of Lester Hawkins ?? his car is in the Year One Next Generation The teal 92 z28. He has had every runner out there known to man. accel, edelbrock,slp, and TPIS. He is a good friend of mine. My other friend owns a Dyno and he will tell you the same thing. The only runner worth a **** to me is the TPIS runners or a Super Ram Setup, or a Stealth Ram. They are very pricey though. Dave Emanuel from Random Technology will also tell you the are no good. If you do not know who he is, he is the Author of the book on how to modify small block chevys, and probably has more written articles on 3rd gen cars than anyone else and on TPI vettes. The reason they are most popular is because they are the cheapest. If I had to put them in orders from best to worst it would be TPIS, Edelbrock, Accel, and SLP.
My edlbrock runners were better than my stock ones much and better than the slps. I have had the edelbrocks,slp, Super Ram, and now I have Stealth Ram. Every person I know has had nothing but bad luck with slp runners. Now I do not know every person who owns a 3rdgen, but I do know alot.

Drew

 

Apparently you know different corvette owners than me. Most of them will agree that the Accel or AS&M large tubes are the best flowing out there, but don't flow well enough to be worth 2x what the SLP runners cost. 10 minutes with a die grinder gets the SLPs 99% as good as the large tubes.

 

Speaking of AS&M large tubes, they flow EXCELLENTLY and i actually have a set for sale..... $300 shipped to your door......

 

Incase you did not know as&m makes the long tubes for tpis. So there is no gain in power over the tpis cause they are the same thing. No matter what you do to slps they will not work better. They may flow a little more or the same, but the main problem still lies in the heat problem. The single tube design cools 3 times faster than a siamese version. All that heat in the runner slows the car down.....

The runners that are for sale in the post below is a great buy some should ****** those up quick!!!

Drew

 

That's why I only mentioned the AS&M along with the accels and not the overpriced TPIS repackaged units.

I understand the heat issue, but I just don't agree. Unless you've got some fancy way of measuring combustion chamber temps, I don't see how you can substantiate your opinion. I don't see how the SLP runners can average more than a couple degrees warmer than the AS&M or stock units even in a worst-case scenario.

Now you've got me wondering. I've got an optical temp gun, and I'm going to do some experimenting with the GTA and the IROC after I get the IROC on the road again. It's not to prove anybody wrong, but hopefully all of us will gain a little knowledge.

 

its all about the knowledge the heat gun is a good idea. run the cars for the same time. then messure the temps right after and then 20min later.. That would prob give you the best results

Drew

 

FWIW....checking the external temperature of the runners will only give you an indication of the surface temperature of them. I think a simpler way of evaluating the air temp is to monitor the MAT sensor that is located in the plenum. This will give you the actual air temperature of the intake charge which is what you really should be concerned with as opposed to what the external temperature of the runners is. I realize that the MAT is located before the runners, however I seriously doubt that given the volume and velocity of the airflow as it passes through the runners that the air temperature would be raised sufficiently enough to have much effect on the performance.
I've spent enough $ on bags of ice to know that icing the plenum and runners in the staging lanes will help lower the e.t.'s slightly but I'm with you Jim in that I really doubt that the difference in the temperatures of the different brands of runners will have any measureable effect.
Now if anyone can figure out a way of easily cooling down the intake manifold base itself between passes, I'd love to hear it. (and please don't say to spray it with nitrous because I've already tried that too

 

When you say the cooling of the intake only helped you a little how much is a little? It helped me by 2-3 tenths and 2.4mph. Its the fact the runners stay so hot the air passing through them will heat up. The stay much hotter than asm large tube"tpis" think about it. A large siamesed thick runner versus an individual thin walled aluminum tube??? not rocket science.

All I am am saying in my opinion is that me and 3 other people I knew slowed down with these runners. Me, Lester Hawkins, Sean frank, Jimmy Coombs are the ones I am talking about. You can even call Dave Emanuel at Random tech and he will tell you to not use them

As for cooling it down the best I always have to bags of ice I use. I lay them sideways accros the intake so the get the plenum and runners. If I only have one bag I lay it on the plenum, and then with my coolant bottle "like a bug spray bottle from walmart" I spray the runners off about 3 -4 times with cold water.

Drew

 

You guys know what Mike Davis's NA 355 TPI LTR set up that ran high 11's used for runners dont ya? IN FACT, He uses the exact same set pictured up there (i know cause i bought them from him!)

 

Drew, I have also picked up about 2 tenths by cooling the plenum and runners so that is a given fact that it does help. Here is something else to think about and it's not rocket science either. A thicker casting will take longer to heat up than a thinner one. If for example, both the thicker runner and the thinner runner are cooled to the same temperature, the thinner runner is going to heat up quicker and transfer that heat to the air charge sooner than the thicker runner. I realize it's going to take longer to cool the thicker casting and if multiple, back to back passes are being made in a short period of time, the thinner runner will have the advantage because it can be cooled quicker than a thicker one.

Here is also something to think about and it is what I addressed in my last statement but I think the point was missed. There is an additional 8 inches of runner length contained in the intake manifold base. If anyone has figured out a way to lower the temperature of the manifold base between passes, I like to hear it because whether thick runners or thin ones are being used, there is even more to be gained if that additional runner length can be cooled also.

Just for the record, I'm not endorsing SLP runners. I personally have a set of Accels that have been ported and I'm pleased with the results.

This thread has gotten quite aways off track from the original question posted and if it continues really should be given a life of it's own.

 

[Here is also something to think about and it is what I addressed in my last statement but I think the point was missed. There is an additional 8 inches of runner length contained in the intake manifold base. If anyone has figured out a way to lower the temperature of the manifold base between passes, I like to hear it because whether thick runners or thin ones are being used, there is even more to be gained if that additional runner length can be cooled also.


Well I did do a small trick here too. Not sure if it helped very much though. I took sandwich bags filled them with water only a little, maybe almost half full. I then froze them overnight before I went to the track. once at the track after a pass I would just tear the plastic bag off them " kept them in a cooler" the looked like little 1-2 in thick ice hot dogs I then stuck them under the plenum.. on the lower base..

Drew

 

http://vette383.tripod.com/ go here and see what this friend of mine did to his vette and maybe some questions will be answered!! I saw the 11.39 pass. He raced my other friend who went 11.34 with almost the same engine combo. The faster vette has 3.07 rear gear, edelbrock intake and stock converter. Both cars naturally aspirated.!! These cars are why I think and Lt1 intake swap is a waste of time. LTR cars can run!!!http://members.tripod.com/~Vette383/1987-CORVETTE.html. And both have ASM runners!

 

notice the lack of slp runners........................



Drew

 

All of this discussion makes me want to get an LT1 manifold

 

thats exactly what i was thinking....

 

I think the lt1 intake is a good intake. I just cant go to one due to the 4in of runner length you get. I need my minimum of 8in to be happy I like a little on the bottom end My old Super Ram setup was making 487rw-ft-lbs by 2850rpm

Drew