Engine GT5.0 Intake vs. Edelbrock Performer RPM

Fox86

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Nov 9, 2020
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Hi together, I am new to this great place. I am from Germany and driving a 86GT and 69Mach1.

Currently I am thinking about changing from the original EFI intake to an Edelbrock Performer RPM. But I am not quite sure what the result will be.

My setup:

- Stock cam
- GT40 heads
- Stock intake
- 75 throttle
- PowerTrax No Slip Traction System
- Ring Gear 3,27:1
- T5 gearbox
- Centerforce clutch
- 24lbs injectors
- NO MAF

I am really interested in your opinion in which sections the RMP might be better. Car is mainly driven in street, but you know, from time you want to kick it as hell ;)

Looking forward to your ideas.
Best
Felix


IMG_8342.jpg
 
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Mustang5L5

Put lubricant all over the balls
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With GT40 heads, that stock 86 intake is definitely a restriction. It would definitely benefit you to upgrade the intake.

You'll gain power overall, but the peak will occur higher in the RPM range with the edelbrock.
 

Fox86

Member
Nov 9, 2020
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Thanks for the warm Welcome. Yes, the previous owner took good care of the car. The whole car is that clean.

You will lose low end torque and gain high end HP.

Uff, will the RPM really steal my low end torque and why? This is not what I expect from a Street car. I know there is no all in one solution, it is always an ‚or‘. My target would be to reach more power from zero, I think this is more interesting for a street or also a 1/4ml car. Maybe one day to add the MAF Sensor, and of course a blower would be a great add-on

Any recommendations for that wishes? RPM yes / no, or good alternatives?

thanks a Lot for you help!
 
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Dan02gt

10 Year Member
Mar 2, 2003
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You would be best served with a Cobra/GT40/Explorer intake (they are all almost exactly the same). They were designed for the GT40 heads and will allow you to get the most out of them while sacrificing very little torque on the low end.

The Performer RPM has shorter runners and was designed to make power in the upper RPM range by taking advantage of high flow heads. On your setup it would hurt your low end significantly and your heads don’t flow good enough to take advantage of the power it makes up top.

The Edelbrock Performer and Trick Flow Street heat would also be good choices for your heads.
 
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Noobz347

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The intake that's on there has obviously had a lot of work done to it. An equal amount of work would need to go into its replacement.

By the time/money that could have been done, you could add one of these and call it quits:

1604978172236.png


:shrug:


Yyyyep. Looks to me like it would fit in there quite nicely. :D
 
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Fox86

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The intake that's on there has obviously had a lot of work done to it. An equal amount of work would need to go into its replacement.

By the time/money that could have been done, you could add one of these and call it quits:

1604978172236.png


:shrug:


Yyyyep. Looks to me like it would fit in there quite nicely. :D

Yep, it would fit, especially for the requirements of the previous owner. I don´t need that "bling-bling" ;)
 

Fox86

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You would be best served with a Cobra/GT40/Explorer intake (they are all almost exactly the same). They were designed for the GT40 heads and will allow you to get the most out of them while sacrificing very little torque on the low end.

The Performer RPM has shorter runners and was designed to make power in the upper RPM range by taking advantage of high flow heads. On your setup it would hurt your low end significantly and your heads don’t flow good enough to take advantage of the power it makes up top.

The Edelbrock Performer and Trick Flow Street heat would also be good choices for your heads.

Thanks a lot for the feedback. You convinced me to forget the RPM - my interest was due to the fact that I could get a "cheap" one here in Germany, but I don´t like the expected result. So I will keep my eyes open for an Explorer intake. Only thing then is to drill the ACT sensor. Then I will have a nice little winter project and a bit more fun in spring time :)

By the way, concerning ACT sensor, does anybody know the bolt/thread size I have to make in the lower intake?

Thanks!
 

Mustang5L5

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It's 3/8" NPT.

The EGR coolant return hose line port at the rear of the intake manifold is also that size. You'll need to drill that. See this thread.

 

Fox86

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It's 3/8" NPT.

The EGR coolant return hose line port at the rear of the intake manifold is also that size. You'll need to drill that. See this thread.


Thats perfect, thanks a lot!
 

Noobz347

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Yep, it would fit, especially for the requirements of the previous owner. I don´t need that "bling-bling" ;)


What I mean is: Keep your intake. It's gorgeous. Add a supercharger, fuel injectors, fuel pump, and a tune instead.

Instead of replacing the intake, replace the CAI with a Supercharger! :rock:
 
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2000xp8

SN Certified Technician
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Looks like the heads are painted so I'd guess they are gt40 irons. The rpm is probably more intake than iron heads need.

With that said, it's a nice engine, pay up for a gt40 tubular and have it polished. It will be worth every cent.
 

Rdub6

So while I wait to figure out my rear end issues
Dec 29, 2017
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Hi together, I am new to this great place. I am from Germany and driving a 86GT and 69Mach1.

Currently I am thinking about changing from the original EFI intake to an Edelbrock Performer RPM. But I am not quite sure what the result will be.

My setup:

- Stock cam
- GT40 heads
- Stock intake
- 75 throttle
- PowerTrax No Slip Traction System
- Ring Gear 3,27:1
- T5 gearbox
- Centerforce clutch
- 24lbs injectors
- NO MAF

I am really interested in your opinion in which sections the RMP might be better. Car is mainly driven in street, but you know, from time you want to kick it as hell ;)

Looking forward to your ideas.
Best
Felix


IMG_8342.jpg
That’s beautiful!! You’re running the stock ‘86 block with those GT40’s?
You have more pics of those cars?
 

Fox86

Member
Nov 9, 2020
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What I mean is: Keep your intake. It's gorgeous. Add a supercharger, fuel injectors, fuel pump, and a tune instead.

Instead of replacing the intake, replace the CAI with a Supercharger! :rock:
That´s not that easy here in Germany. We have the Advantage that the cars are "historical", means older than 30 years. So you have cheaper insurance, taxes etc. In consequence the car need to be "original" or build from parts of the decade. I still have the supercharger in my mind, because I really would like that, but before there are some Things that Need to be clarified.

For the Moment I just bought an Explorer upper & lower ;)

Step 1 check
Now a A9l would be nice, but not that easy to find...
 

Fox86

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That’s beautiful!! You’re running the stock ‘86 block with those GT40’s?
You have more pics of those cars?
Yes, the GT40s on stock block. Runs great, but I´m sure there is some additional potential soon with the Explorer intake I decided for :)

Here just a quick pic, I have right now available..

Kisten.jpg
 
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7991LXnSHO

wanna catch the space herp
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I wonder if an expert porting the lower Explorer intake is an option in the EU? Having @tmoss port it is a good power and value option in the states. But UPS Ground can get expensive when an ocean is involved. I do not think the brown trucks float and they end up using airplanes. :shrug:

I’d still see if it was worth the shipping to keep the low end torque and open up peak flow.
 

marcelo

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hallo Felix .. bohh super clean !! sehr schoen...... wie alle schreiben .. Torque geht verloren in den unteren und mittleren Drehzahlen dafuer oben raus mehr .. ich hatte so ein teil drauf als ich meinen 92 bekam ..habe dann aber den Intake verkauft und ein original Tubular mit bearbeiteten kanaelen montiert ..der unterschied ist schon markant.. viel mehr Power in den mittleren drehzahlen ..und halt oben raus wird er ein bisschen lahm weil eben die Kanaele zu klein sind und einfach die Luft fehlt...da helfen dann auch die Nockenwelle und die AluKoepfe nicht mehr weiter ..die Bremse sind die kleinen Kanaele im unteren Ansaug ..schlimmer noch mit dem Stroker motor.. aber wenn du keine Rennen faehrst oder so ... alles nicht so schlimm...wenn du mehr Sprint willst .. dann besser ne andere uebersetzung 3.73 oder so .......