I just got my car running and driveable a couple months ago, and am now looking for more things to do to it. I'm debating about throwing on a Performer RPM/ Performer RPM airgap. Do you guys think this would be worth the money for me combo...or if I would notice the difference?

COMBO

333cu in
Accel HEI dist
K&N air cleaner
600cfm edelbrock electric choke carb
Edel performer intake
Edel Performer rpm heads
crane cam 216 duration .454 lift 110LSA
roughly 10.5:1 comp
1.75" headers, 3" collector 2.5" exhaust flowmasters

I suppose the rest doesn't matter much.

I'm just wondering if you guys think this would be a noticeable difference on the car. Any input for a different intake, if worthwhile, would be good too.

car has a TH350 (2K stall...larger stall or 4 speed a.s.a.p.)and I will soon be re-doing my 10bolt with 3.73 or 3.90 gears, posi, different axles...not sure which..... & drag radials.


Any input would be appreciated. Or any ideas on how to pull some more power out of her somewhat cheap.

Thanks
-Ben

just my thoughts now but i believe a set 15/8s headers would do you more good than the intake.the difference in bottom end torke would probable be felt in the seat and would also yeild a quicker et

I think the rpm airgap would be the manifold of choice, especially with the capability of the heads. A little larger cam would also compliment the rest of the package say 230-235 degrees of duration at .050. The 10.5-1 compression would also like more cam I bet. JMO's here

Agree about the intake and the headers. Get an RPM on there and 1 5/8" headers. You may want a little more stall if you plan on keeping the TH350 - you don't have a lot of low-end torque. The gears will help in that dept also.
Good luck!

Thanks for the replies guys. I definetly need to get some new headers soon. What are 15/8s headers? I'm sure i'm displaying my ignorance here, but i've never heard of that. Would someone be so kind as to enlighten me? So the air gap is the way to go?

Thanks again for the replies

-Ben

he ment 1 and 5/8" headers graemlins/thumbsup.gif

ahhhhh well that makes more sense then. WILL DO! Do you guys recommend a certain brand of headers? I want something that's stainless and ceramic coated. Currently i'm having a lot of space problems with my headers. There's just no room to get a wrench in to get to spark plugs, not to mention burning/melting everything around it. Is there anyway I can find a set of headers that won't cause these problems? I mean I don't care if it's hard to get to the plugs or anything...that just goes with these cars, but i'm just sick of burning ignition wire boots and different wires to various things. I had to throw header wrap on these headers just to be able to use them. It's pretty rediculous.

Depends on how high you buzz it up. What rear gear do you have? If you generally don't go north of 5,500 rpm, I'd say stick with an Edelbrock Performer.

Mike

I wouldn't worry about the RPM manifold hurting low end at all. In my experience, these work well even on mild applications.

I has a 8.2:1, 204/214 cam 350 in a '70 Nova once. I went to 1.6 rockers and swapped the cast iron intake for a RPM Q-jet manifold (two changes at once, so it is hard to say which had the greater impact). The car felt better throughout the entire rev range (including low end with a stock tq converter), and picked up 4-5 mph in the 1/4! :eek:

Granted, your performer is better than my stock iron manifold, but IMO, the RPM should really help the midrange. Make 1 5/8" headers your first priority though.

As far as headers go, well, that's what you get more often than not. I've heard that higher dollar headers fit better, but I've never been able to afford a set. We have header wrap on ours, but what was really nice was buying those insulated plug boots. Those really stopped the problem of always burning wires on the headers. It was a worthwhile addition under the hood.

I'll let others recommend brands. I don't even remember what brand is on ours, but I think it's Dynomax. I do know that on plug on the passneger side is extremely hard to reach, and we have to use shorty spark plugs or it would be impossible to install one on that cylinder.

Sounds good. I suppose I could always ask the summit tech guys and see what they think. It would just be nice to be able to get to the spark plugs without having to remove a bunch of parts off my engine. OH WELL. What power differnece do you guys think there would be by switching to the 1 5/8" headers? Maybe 10hp or so? Just overall better flow being felt? Just curious.

Thanks
-Ben

If your going to go with the Edelbrock RPM, go for the Air Gap for sure. 1500 to 6500 RPM advertised usage and make sure it will fit under your hood.

Sounds good. I'll be going with the airgap when I get a new manifold. I'm pretty sure it'll it under my hood. I actually have some good clearance. *thank God*

Thanks again
-Ben

come on guys 1 3/4 hooker super comps the best bar none... from mild to wild with room to improve top end stuff like cam , lifters , porting higher stall speed later in the performance game ... i without a doubt would throw that 600 eldebrock carb directly in the dumpster get a holley 3310 (750cfm) vacume secondary along with the rpm air gap manifold eldebrock makes excellent stuff but they should stay out of the carb buisness. ya ever been to the track and seen more than 1 outa a 1,000 cars thers a reason for that ...my 2 cents

I'm assuming that 333ci is a bored and stroked 307ci right? Reason most everybody is recommending the 1 5/8" primaries is becasue they'll help that smaller motor out by giving it better bottom end/torque...whereas if you go with the 1 3/4" primaries, you motor will run out of breath in the high rpm ranges. Almost like putting a dual 3" exhaust system on a bone stock 283ci. Sure it'll "sound kool", but it won't do diddly squat for your performance. Now here's another thing....what are your plans for the car/motor in the future? Do you plan on going with a 350? 383? bigger? Or are you planning on keeping it a street car with some decent "umph"? If you're planning on going with a bigger motor, I'd say save your money for the bigger motor. Although you could probably bolt on those 1 3/4" headers onto your 333ci, who's to say you don't change your mind about a motor, and go with something else instead? Like a BB?
If it's a daily driver and nothing else, you can't go wrong with 1 5/8" headers. But ultimatly it's up to you.

im assuming his 333 is realy a 331 wich is a 327 .030 over and 1 3/4 headers are fine for that combo a little on the big side but not that much at all and gives plenty of room for future mods why buy 1 5/8 to throw them out in a year . again my 2 cents

Originally posted by 71chevy0192:
ahhhhh well that makes more sense then. WILL DO! Do you guys recommend a certain brand of headers? I want something that's stainless and ceramic coated. Currently i'm having a lot of space problems with my headers. There's just no room to get a wrench in to get to spark plugs, not to mention burning/melting everything around it. i just switched from an older mr gasket 1 5/8 header to dynomax ceramic coated ones this year. a custom exhaust shop recommended them saying they were the best for the money. i have to admit i am very happy with them. they look great with that coating and i definely have more room with these to get to the bolts and plugs. that was an added bonus because the old ones had a couple of bolts that were a real nightmare to get a wrench on. i also would advise staying with a 1 5/8 header with that engine, i suspect you would loose torque with bigger ones JMHO. p.s. make sure to use a good anti-seize on the bolts when you change them out.

First of all, it is a .040" 327. Technically a 333 cu in. I plan on keeping it a street car with some get up and go to it. Currently, with an educated guess, i'd say it's a low 14/high 13 car right now. It ran a 14.5 1/4 with a bunch less done to the old motor....everything else the same. Unless this motor destroys itself, i'll be sticking with it. It's a good running engine and has a good amount of kick to it. Basically if I can pull 450hp (flexplate) out of it, that will be good enough. Shouldn't be a problem really. ANYWAY..... =^D So there's some controversy on the 1 5/8" headers now. How much of an improvement do you guys think there would be by switching from the 1 3/4" to the 1 5/8"? I mean why would it be better to switch to smaller tube headers? Torque? Just curious.

Last question.

What do you guys think the combo I have would run with the following changes.

Performer RPM Airgap
3K stall or M22
redone 10bolt with 3.90/4.10 and posi

I'm thinking low 13's. Just curious as to what you guys think. It's really not that important though, and I know it's a general question. Basically I just intend for the car to be a fun street car. The only thing I might do later would be to throw a nitrous kit on, running a 100 shot or so....if everything else goes good.

Thanks
-Ben

Well if it's going to be more of a street car, I wouldn't recommend going with a 3K stall converter....then again, I have heard others that do run a 2800-3000 stall and "have no problems." The main concern with a stall that high, especially in a street car is "cooking the tranny." If you have the tranny, or access to stick, I'd go that route. I don't want to be one who "rains on your parade", although I can be obviously wrong here, but I kinda think your expectations of it running low 13s are slightly high. Definatly not impossible tho, but I think it would be a sold mid 13.50-13.20 car for sure. How heavy is that car right now? Have you taken anything out? Do you plan to? How much do you weigh?...although it's not really important for us to know how much you weigh, but it does play a role.

I feel, if you want a solid low 13 sec car, you'd be better off going with a solid cam, possibly in the .520" lift range, and if your going automatic, a stall around 3K, posi with 4.11s out back and definatly putting that car on a diet. I'm no profesional here, just another gearhead who's trying to pass some honest advice that was given to me. If I'm wrong anywhere, please feel free to help me out and educate me as well as others.

The thing about the header primary size...it was put to me this way...
dual 3" exhaust systems are for motors producing over 500hp....1 5/8" headers are for motors that are producing roughly 350-400hp, and 1 3/4" primaries are for motors putting out 400hp+ ....again, it's not written in stone...something that was just explained to me. The thing about going with a smaller primary is so that you benefit from the extra backpressure, which is basically torque. I know this is another argument all together, but, I believe that torque is what moves your car, and gives you that "in the seat of your pants" feeling. Along with the smaller primary, your motor won't be running out of breath in the upper rpm ranges. Sure you can buy 1 3/4" primary headers, but you'll be loosing out on that top end. Yes you did mention the use of nitrous, which the 1 3/4" headers can benefit from, BUT! you're not gonna be using nitrous every time you drive the car. You said it yourself, you plan on keeping it a street car with some get up and go to it. Well, that get up and go is torque. My intentions are not to make this post an "all out war" of who's right, wrong, or whatever. We're all a bunch of gear heads looking to help another gear head out. We've all been somewhere, and we've all done something. It'll ultimately come down to what you know, what you've learned, and what you feel most comfortable with. graemlins/thumbsup.gif

graemlins/thumbsup.gif tip of the hat to LXS above, one of the most sensible posts i have seen on here and i have seen some good ones. my own experience tells me that if you are building a hipo engine with small cubes it needs to go into a VERY light car and you should max your rpm capability cuz that is going to be how you make your horsepower (absent cubic inces). i also think a four opr five speed is far superior to an automatic in this application. a great small cube performance example was the '68 or '69 Z28. just look at the elements of that entire package and that will give you some good guidance on what you need to do.

p.s. my comment on going with smaller headers was based on the premise that you were staying with a more modest build on that 327. if you are building to 450+ hp then that may be entirely different.

Point well made guys. I appreciate the sensible, non attacking posts. lol Yeah, I definetly want to go with a manual transmission, but i'm still figureing out which one. The 3k (or somewhere around there) stall was just going to be something I would throw in to get it rocking and rolling a little better before I throw a manual trans in. I hope this doesn't start another one of those lengthy debates about auto vs. manual. I just think manual is a lot more fun, and that's what i'm building the car for. With half a tank of gas the car weighs almost exactly 3400 lbs. It has bucket seats. The seats aren't stock, and are VERY LIGHT. The back seat is all foam, covered in cloth, and can't weigh more than 25lbs. A good portion of the parts under the hood are obviously aluminum. I will be getting aluminum rims, and an aluminum driveshaft sometime in the near future, so that will help also. Currently I have steel rally's and what I believe is probably a stock driveshaft....either way, it's not aluminum. I suppose i'll just have to get these things done, and then post my 1/4 mile times.

I kind of based my engine off of the Performer RPM package engine that Edelbrock did some time ago. I believe it made 465hp. I realize that throwing an engine together with the same parts as this will not necessarily produce the same results. I'm hopeing that my engine is currently close to 400hp. It may get a larger roller cam later on also.

What would you guys think this engine is putting out for hp and tq right now? j/w I can post all other specs if needed.

Thanks again for the posts and advice

- Ben

Forgot to mention....I only weigh 160lb's or so......not too much extra weight for it to move. lol

I'm not very good at guessing hp/torque...but I'd guess roughly between 330-350hp. Could be wrong though...and that's not a first tongue.gif I would love to go stick in my Velle, but I don't have the funds for a "major" project like that. It's bad/hard enough just keeping up with the rent and bills, let alone throwing money at my car. Looks like, to me, you've got a really light Chevelle there....sniff sniff, I'm jealous lol :D I have no idea what mine weighs, but I'd guess roughly 3800lbs...without me graemlins/clonk.gif I've got a lot of tools and junk in my trunk, so that's why I'm guessing that much. I weigh too much right now as it is...roughly 2 of you, minus about 20-30lbs, and you got me. I was 40-50lbs lighter, but after pretty much sitting around doing nothing, due to my back injury, I "couldn't help" but gain weight tongue.gif :D
As for that Performer RPM package your baseing you motor on...wasn't the motor a 350? Correct me if I'm wrong, but I do believe that the cam it had was around .525" lift? Give or take some lift. According to your specs, your cam is almost .100" smaller, and you stated that your using a Performer intake. Good pieces, but not enough to make 465hp, or 400hp IMO...but I could be wrong. Again, not trying to rain on your parade, just going on what knowledge I currently have. As for going with a bigger roller cam, that's always a good idea. While your at it, you might want to invest in a Performer RPM intake along with some 1.5 or 1.6 roller rockers. I feel that if you really want to go above 400hp without putting too much strain on your motor, your best bet would be going with a 350 or bigger. Again, not that it can't be done with that 333ci of yours, but it's well known that the more hp you try to make out of a smaller motor, the more radical and stress it is going to have to be and indure. Keep us posted, and keep the questions rolling in...we're more then happy to help out graemlins/thumbsup.gif

LXS - Sorry to hear about the back injury. Yeah, that edelbrock package was done on a 350. I only mention it because eventually I will be throwing in a similar cam, and going with the performer rpm intake. The new cam will probably be a hydraulic roller cam though. I neglected to mention it, but I already have 1.5" roller rockers on it....not that it matters much. After everything is said and done it will be a very similar engine, except it will be a 333 instead of a 350. After talking with a bunch of people on this site, the majority felt that the engine could handle up to 600hp. The bottom end is fully balanced, forged crank, ARP rod bolts, stock rods (wish I would have put some others in, but these should be fine), forged pistons, 2 bolt ( I know, but it's what I had). I'll be happy with 400hp (off juice) 500hp (on juice). It should make for a fun car. 330hp - 350hp is roughly what the guy who put my engine together thought it might be putting out. I REALLY want to get her on a dyno. It would be awesome to have it tuned properly, and not have to guess on hp.

How do you like the 388 in your 71'? I almost did a 383 instead of this 333. Sounds like you have some pretty crazy/badass rides there.

-Ben

Thanks Ben. My 388 is fun, but I never got into the "process" of tunning my carb. I always ran it as is. For what it is, I feel it's pretty quick, but now I'm starting to tune my carb. I know that it's not running the way it should, but after tunning the carb, experimenting witht the jets, etc., I'm believeing that I'll have a "brand new" car after everything is said and done. I'm hoping that by roughly this time next year, I'll have all the bugs worked out, and a good 150 shot to play with at the track :D I'm not a hard core fan of nitrous, but hey, 150hp at the press of a button sure sounds good to me graemlins/thumbsup.gif

LXS - Understood. Carb tunning is something I also definetly have to do. I know what you mean about the nitrous. I'm currently debating about whether or not I want to throw on a nitrous kit in the distant future. It would be nice to have the extra power available if I wanted it, but then again, there can be a lot of problems that come with nitrous. Speaking of carb tunning and all this I have another question. I believe all my fuel lines are 3/8". Is this too small for my combo? Would I benefit from running large gas lines? Just curious. This is something I haven't looked into much yet. I think this might be the next issue to take care of for my car.

-Ben

Well you'll get a whoooooooole new "topic" of responses regarding fuel line sizes....believe you me!!! I asked a while back, and I had soo many guys telling me; go bigger, stay with what you have, go smaller(well not really smaller, it just looked like it "completed" the statement tongue.gif ). Well, unfortunatly my car is an original 307 car, so that means I've got 5/16" fuel lines. Some guys told me I'd be perfectly fine with 5/16". Others told me 3/8" is what I want and that it's the perfect size....and that their original BB cars came with them, and that's what's best. And very few told me that I'd be better off going with a 1/2" line..."You want volume over pressure." Basically, the smaller the line, the more pressure there is, but it is still volnurable to starvation, whereas with a bigger line, there's always volume, and you never have to worry.
My suggestion would be, if you plan on going with an all out street/strip big block later on, then you'd be better off going to a 1/2" line. If your plans are only to keep the 327/333 you have now, and don't intend to build it up, then your better off staying with the 3/8" line. As for myself, I plan on going with a big block.....as for when.....who knows??? But those are my plans, therefore I'm planning on swapping over to a 1/2" fuel line from tank to carb. Right now I've got the stock 5/16" line from the tank to the pump, then rubber 3/8" line from the pump to the fuel reg to my carb. I have a friend who has the "hook ups" to get me a really good deal on steel braid hoses and fittings, so before he leaves that job, I'm gonna get some 1/2" steel braid to replace all the 3/8" rubber line. Then later on, not sure how I'm gonna do this, but I'm gonna try to install 1/2" line from the tank to the pump.
If anything, if/when you plan on installing a nitrous kit...you could always keep your 3/8" line, and install an electric fuel pump and separate fuel line just for when you use the nitrous. That's something I'm thinking of doing if/when the time comes. smile.gif

All good points. I just realized that the line I was checking was only from the pump to the carb. I still need to measure the line from the tank to the pump. If it's 3/8", and that's not terrible?, then I guess i'll just stick with that for now. Is it hard to replace all that line? I've never done it before. Pretty much just running hard line (mostly straight) from the tank to the pump, and then probably soft from pump to carb right? Having smaller line than recommended won't hurt anything will it?

Thanks again
-Ben

Originally posted by 71chevy0192:
Having smaller line than recommended won't hurt anything will it? What do you mean by that? Did the guy who you bought your parts from, or who built your motor say to go bigger? Or did another gearhead say to go bigger? Regardless, I believe that 3/8" fuel line is more then suitable for your current motor and your intentions towards it.
As for changing the whole fuel line from tank to pump....I've never done it. I've heard that it can be challenging tho. The only hard part that I've heard of is outline on the tank itself. If I understood/remember right you have to baffle/vent your gas tank so that you can either replace/take out the stock "outlet" and somehow make it bigger and weld in the new bigger outlet. Don't quote me on that, but it's something along those lines. When the time comes to do mine, I'll either try to really do my homework on it, or just say the heck with it and pay someone to do it. Either that or I'll just dump the tank completely and bolt up a fuel cell :D

if that thing runs high 13's with the parts you say it has, i'd be afraid to change anything on it, for fear of slowing it down. you aren't going to get an honest 450hp out of a 327 without dramatically increasing your rpm range upward. it cracks me up the way guys say your headers are too big and won't make any torque, then suggest that you go with a bigger intake and a cam that's over .500 lift. you'll lose more torque that way than by keeping your 1 3/4" headers, which i take are already on the car, right?

m71 - actually i'm not really too concerned about running the 1 3/4" headers. But yes, they are currently on there. What you might not have noticed was that the cam and intake will/may be done after throwing in higher gears (numerically). If I go with that change, then I will be throwing on nitrous also. AGAIN IF I do put in a different cam and intake, then my plans will have changed from a fun street car, to a semi serious drag car. The changes at that point being....

Larger cam
RPM AIR gap intake
larger carb, lines, and fuel pump
nitrous kit
3.90 or 4.10 gears
5 or 6 speed....looking toward a new T56


still working on figureing out what I plan on doing with the car.