76Cutlass_442

Hello Everybody, I was wondering what would be a better Application for my 76 442 Equipped with a Performer IntaKe, Quick Fuel 600 cfm Slayer, Hedman Long Tube Headers, with X Pipe to Flowmaster 50s..

What i want to do is make the Car a Low 14s Car. 0-60 in Sub 7 Second Range.

Its a 75 Engine (Early 76 Car) wouldn't that have 14 CC Pistons that i wouldn't have to change out? The Car is getting 3.42 Posi. ALSO Edelbrock Heads over Stock Irons? Rpm Intake Or Perfomer?


Please Help!

cut123

I would skip the performer. The rpm would be better with your gearing and give you room to grow.

coppercutlass

since he already has it no need to get rid of it for his goals. I went 13.86 with the performer & 3.73 gears.

cut123

Very true.

captjim

I did a test between the 2 years ago, the data got lost in an ROP crash. On a 9 to 1 355, 210/216 cam, mild head work, 1 5/8" headers, 3.42 gear, 2600 converter in a heavy car, it was quicker with the Performer, revved faster, and was noticeably more responsive at part throttle. Ran high 13s, shifted at 4600 rpm.

76Cutlass_442

Thanks Alot everyone for the responses! so Keep the Performer? Would running a 1" Spacer help at all?

olds 307 and 403

Jim did a nice real world example. I know another racer has seen gains going to the rpm even on stock Vin 9 307's. Of course that racer runs Qjet carbs on nearly everything. A spacer sure shouldn't hurt anything but back to back runs will see if it truly gains anything.

1BOSS83

Jim I don't understand- The car was quicker with the performer compared to what?

Seff

Compared to the Performer RPM, I assume.

captjim

Yes, as was the title of the thread, in that combo the Performer was a tenth quicker in the 1/4 mile, revved faster (shift points were closer together), and had noticeably better throttle response versus the RPM.

wr1970

Jim the reason for that is the performer intake was working at it's advertised performance RPM range!The performer rpm intake didn't achieve total optimum performance range because the engine was not capable of reaching the rpm for that to happen.Your engine was done at around 5300 rpm. I would venture to say you didn't cross the line at 5500 rpm. This is not saying that you didn't have a good engine. It just wasn't up to the performance level of what is required to use a rpm intake. To the op the performer is a very good choice for a mild engine.

captjim

Fair enough. But, the Performer is often mentioned as nothing but an aluminum stock replacement. IMO, not true. My contention is that the Performer is under rated and a better choice for a lot of street engines in the 9 to 1 cr/300 HP neighborhood. Olds engines (unless heavily modified) perform best at low and mid-range RPMs. I used a 100 HP shot of nitrous and ran 12.7 shifting at 4800. Yes, 4800. Again, keep in kind that this combo was far from stock. Porting, headers, larger cam, converter, gear, etc. Yet it still performed better with the Performer than it did with the RPM. I did a BUNCH of track testing, best ETs were obtained shifting at 4600.

wr1970, have you ever done a real life comparison of a Performer and a Performer RPM manifold on a mild/hot small block Oldsmobile engine or are you basing your statements on info from the manufacturer or other information?

The RPM advertises itself as far as rpm range goes 1500-6500 rpm. I promise you that the VAST majority of street driven Olds engines will perform better below 3,000 rpms with the Performer than with the RPM, which is where the engine (on a street car) spends most of it's time.

cutlassefi

One thing all of you may not understand, when manifold companies list a usable rpm range, that's for the whole group of engines listed. For example, a 330 will have a higher rpm range than a 403 with the same intake, all else being equal.
And have you ever looked at the runners on an rpm? They're still tiny by most standards.

captjim

That really isn't a sentence. My point is a LOT of guys spout stuff without any real world experience, reiterating anecdotes or manufacturers claims. I am not saying a Performer in "better" than an RPM, I AM saying on my combo (9 to 1 355, mild cam, headers, converter, gear), the car was quicker with the Performer. I do not care about runner size or anything else, all that mattered to me was how the car ran and how much fun it was to drive.

cutlassefi

I understand that. But just thinking, is there a possibility that it would've run faster with an RPM shifting at a higher rpm? Hmmmmmmm

wr1970

Jim i base my opinion on real world track results of how a performer worked for me. I used a performer for several years on one of my race cars. This isn't a slam on you or your build. The performer rpm on the right build is very good how do i know seen one on a buddy's car at the track. But he still didn't take full advantage he wouldn't push his beyond 6200.He was running around 11.78/11.84 with a 461 ci. He said he was shifting at 5700 but lagged a little so his engine may not have had enough grunt. Maybe a convert would have helped him more 3600 stall was what he used. I think 4500 or 5000 may have had a benefit. Carry on guys.

captjim

Now you are talking big block? Apples and oranges, not the same at all. The BBO Performer is more like a SBO RPM. Also, we are not talking about race cars.

wr1970

They both are street driven. My best et with a performer is 12.50.

captjim

Not on my combo. The ETs were very close, like .10 quicker with the Performer. I tried, making many more runs with the RPM than with the Performer, best ETs were shifting at 4800, once I got over 5,000, ETs dropped off. More gear would have probably made a difference. It just took too long getting there.I think that at a little bit higher performance level (a bit more compression, cam, head work) the RPM would be a better choice. My build was right on the line between the two, I was as surprised as anyone by the results. My point is that the Performer, IMO is a better choice in most instances for mild, street driven, SBO builds.

captjim

Big block or small block, they are completely different animals.

captjim

13.9 n/a, 12.7 with a 100 shot. In both cases, best ET was shifting at 4600.

coppercutlass

I edited that out as i was confused. But i found when i was running high 13's with the performer the power fell at 5k but i also had a small cam. Right now the car runs the fastest shifting at 6k. i have not bothered bumping the shift point any higher.

wr1970

Think what you want! A pump is a pump big or small everything depends on what you put in them for best result. In your case jim i agree the performer was the best choice.

coppercutlass

I may add im running the performer rpm at the moment and the power is still strong at 6k. but shifting at 6k im trapping right under 6k rpm

captjim

That is an absurd statement. The extra 100+ cubes and 150 ft/lbs of torque that go along with it changes everything. It makes up for anything you lose down low on the smaller engine.

captjim

Once again, not an apt comparison. Let's stick to the parameters of the original post; a low compression 350 in a heavy car, not a 461, not a high comp 355 with a big cam.

coppercutlass

It was fwiw comment. I posted what my little low comp 350 did and for what it was it ran damn strong.

captjim

I think most everyone will agree that on a high comp 355 with a big cam and gears, the RPM is a better choice, but that is not what we are discussing, so why bring it up? Why not add that so and so is running high 10s with a Victor. Oh, BTW, it has 11.8 to 1 cr, a .650 cam and 4.88 gears.

coppercutlass

Maybe the Op needs to know why the performer rpm isnt the best choice. it all leads to a touch of topics where people will learn why., and not just be told what to run.


Just as a side note. Im running 10 to 1 compression, and i found out it will run on 91 octane and last 2 times i drove well over 100 miles round trip to the track and back so . still a street car. great manners on the street. so my car still rides a fine line where its completely streetable.


i agree its a little unrealted but im on the other end of the spectrum where it can be used to find out that fine balance in between a low compression or high compression engine. I had a 9 to 1 350 that ran 13.86 now i have a 10 to 1 355 that runs 12.80 .

captjim

How do you know it is not detonating? They don't call it the "silent killer" for nothing.

coppercutlass

Didnt run it on 91 all weekend. Got stuck pumping it at a little gas station in the middle of no where. considering my timing is on the conservative side its safe to say im ok. we will find out when i take it all apart this winter to inspect it all. I wanna see how its all holding up.

wr1970

Why are you always so sarcastic Jim. Didn't Copper and i agree that the op needed the performer intake with his combo! You also thought that that was the best choice.I don't think i disagreed with you.The discussion got off track a little but the question was answered.

s i 442

Whats a mild cam, converter and gears?

captjim

I clarified that in post #5 in this thread.

76Cutlass_442

Thank you everyone for the very helpful Information! The Performer will stay on the car with the build, Thank you!