Edelbrock EFI Intakes: Performer vs. Performer RPM

[90mustangGT]

How would one effect the powerband differently from the other. The lower's are the same, but what kind of differences does the two different uppers make? Pro's and Con's.




I have the Edelbrock Performer now. I am just wondering what difference I would get with the RPM.

 

[Jkstang78]

Here is what it says on the edelbrock website

Performer RPM 5.0 (1500-6500 rpm)

Designed for 1986-95 Ford Mustangs with 5.0L V8, the Performer RPM 5.0 EFI manifold is for nitrous, supercharged and bracket racing applications. It uses the same base as the Performer 5.0 manifold but the upper plenum has shorter runners with a larger cross section for more power in the 5000+ rpm range.

 

[FiveLtrRiceEatr]

it really depends on your mods, what are you going to do to your stang? I saw in a previous thread you were looking at TFS or AFR's, if so you should definitely go with the RPM or the RPM II (if you want a little more mid range power). RPM beats the RPM II on the low, but dominates in the mid, so it really depends on your combo! and yes the power is 1500-6500 RPM. So there is a difference, go with the rpm or rpm II

 

[stang2841]

I got the replica RPM intake... and from seeing my buddys RPM intake... its a nice piece.


if your going with AFR's I'd say RPM II

 

[90mustangGT]

From what I have understood, the RPM is a little shorter and has a larger chamber area in the back, but if that would make a reasonable difference I don't know. The RPM upper is $300, the RPMII is similar but it all has to be replaced so I'm looking at $600 there, but is much larger. Maby the smart thing for me to do would be to re-use the Performer and maby make that decision later if it starts choking anything.

 

[Grn92LX]

Depends on the camshaft choice. I would definatly use the RPM though, unless low end torque is your MAIN concern then keep the performer. You use a comp 270xe cam, right? My friend had an afr/rpm/fti car and his car pulled higher than mine but also his low end torque was still fine.

How fast do you wanna go? Goals? I still say stroke it since the engines out

 

[90mustangGT]

I will build this engine with priority towards the track. Maby I should just sell the performer and get a RPM II. Becauses the RPM upper is $300, a new intake is $500, if I got $300 for my intake the RPM would cost the same. Since I plan on getting a cam from them anyways, I think I will call FTI and ask them what I should do. They have recomended the regular performer before to mainly street applications.

 

[Grn92LX]

For a primarilly track car with say 11 second goals, use the RPM II (be sure to open up the inlet for a 75mm TB at least) I asked Ed a similar question and his recommendation was holley or RPM II. That should work nice with the 165's you have planned. I would suggest the 185's though. I can tell you my buddy had a 306 with 185's and on average he is about .5 faster than most afr/fti guys on here and that was before he dialed it in. 185's, RPM II and a fti or jay allen cam and hello mid 11's with ease. The 185's are the same price and they are also ok for a mild stroker as well

 

[5spd GT]

Yep I have the Performer on my street application...Ed recommended it to me over the RPM because of a more useable powerband...and torque wasn't my main concern as I told him...just that I drive it everyday and didn't want that to suffer...it seems to flow well at the upper rpms... and I have the AFR's that help a little I guess

A guy on here said he went to the upper RPM and gained mph but lost some E.T. or something like that...

Just ask Ed or any of those associated with working with the Edelbrock products and see what they suggest for you...

 

[5spd GT]

I can tell you my buddy had a 306 with 185's and on average he is about .5 faster than most afr/fti guys on here and that was before he dialed it in. 185's, RPM II and a fti or jay allen cam and hello mid 11's with ease. The 185's are the same price and they are also ok for a mild stroker as well

Well your buddy is probably a better driver than half on here also...as well with the highend power and fresh bottomend that helps...

With ease?

 

[Grn92LX]

His mph was better as well for an untuned car. That engine is going into my other friends car so i'll be tweeking that one once it goes in. I'm not going to give that combo away over the net though, it does have afr 185's though.

With ease if he can hook I mean I definatly set him on with a mid 11 potential combo.

 

[90mustangGT]

Thanks for the input. I see what you mean. I race the 1/8th a lot, maby stick with the regular performer. I guess I will just make a phone call or two. Honestly, I don't see where I could loose, any which way I go, except my wallet.

 

[Grn92LX]

When your racing your wallet theres no way your gonna win that race I'm not sure how to set up an 1/8 mile car. Do you street race at all? Since your doing a 306, shoot for like 11:1 compression with the proper piston that will allow for lots of clearance. Use the afr 185's, RPM II intake (or rpm if you feel the II is too much) talk with ed or jay for a cam and tell him how fast you wanna go. Use a 1 5/8" LT header and whatever gear is needed and shift at 6500

 

[90mustangGT]

When your racing your wallet theres no way your gonna win that race I'm not sure how to set up an 1/8 mile car. Do you street race at all? Since your doing a 306, shoot for like 11:1 compression with the proper piston that will allow for lots of clearance. Use the afr 185's, RPM II intake (or rpm if you feel the II is too much) talk with ed or jay for a cam and tell him how fast you wanna go. Use a 1 5/8" LT header and whatever gear is needed and shift at 6500

That is kind of what I want to do. I am planning on selling my Cobra R's and getting a set of Welds and running a 28" tall DR, either MT or BFG and probally 4.30+ gears. 4.30's on a 28" tall tire would be similar to a 4.10 on a 26" tall tire, somewhat closer to 3.90's though. If I build a 306, it's going to need to revv and make plenty of power up top. 185's and a RPM II would probally make the top end power and maby with a steep gear like that I can benifit from that kind of combo. Also, with 185's, I would have more room to grow if I wanted to do a 331-347, but I think I'd rather do a 408, well, that will be another thread wayyyyy in the future. Thanks.

 

[5spd GT]

I can tell you my buddy had a 306 with 185's and on average he is about .5 faster than most afr/fti guys on here and that was before he dialed it in. 185's, RPM II and a fti or jay allen cam and hello mid 11's with ease. The 185's are the same price and they are also ok for a mild stroker as well

Besides the heads helping to change the compression...I'm guessing that the 306 in question is of higher compression right? 10:5?

 

[Grn92LX]

That is kind of what I want to do. I am planning on selling my Cobra R's and getting a set of Welds and running a 28" tall DR, either MT or BFG and probally 4.30+ gears. 4.30's on a 28" tall tire would be similar to a 4.10 on a 26" tall tire, somewhat closer to 3.90's though. If I build a 306, it's going to need to revv and make plenty of power up top. 185's and a RPM II would probally make the top end power and maby with a steep gear like that I can benifit from that kind of combo. Also, with 185's, I would have more room to grow if I wanted to do a 331-347, but I think I'd rather do a 408, well, that will be another thread wayyyyy in the future. Thanks.

I could have sworn you said money was a concern? Now your talking a 408? I would go with the 26" tire/410 combo unless you'll be running the slicks on the street as well? 185's would work nice on a mild 302 based stroker(400rwhp range) I still say since the engine is apart just spend a little more and do a 342/347. You wont have to rev it as high to make power and if you chose to rev it higher it will make even more. Afr 185's, TFS R intake 75-90mm tb, 1 3/4" lt's and custom cam will do 400+. Just another possible route Balance it to 50oz to save money.

David, my friends old 306 was somewhere in the 10-10.5:1 range. This engine is going in my good friends car soon and i'll be helping him choose parts for it(inj,tb,maf,intake manifold) and dial it in. I'd like him to swap the cam in it for a custom but theres that money factor again

 

[90mustangGT]

Money is an issue, that's why I said it would be way in the future. The truth is, I really can't afford what's going on in the first place. I have credit, but won't use that to build my car. I'm still recovering form the TKO I had to buy last summer. My idea, 11's on motor, maby later 10's on spray. I'd love a 347. I am going to wait until I get the motor torn down to make that decision. If I need to turn the crank, and do too much prep to the stock components, I'm going to definatly stroke it. I have a Romac balancer that I could sell and get somthing for to take away the bite. To me, it's all about HP:$$.

 

[tmoss]

The Performer/RPM lower intake needs porting to really let the potential of the AFR/TW heads loose. Using the Performer or RPM upper will just shift the power band up some - all else being held equal. I thionk the Performer would have better under-the curve numbers if worked professionally due to the longer runners - more average torque/HP.

You could prove me right or wrong by doing the Performer you have, and then making a switch later to see what happens and sell the intake(s) for close to what you have in them.