Hey, I need a little help. I have no knowledge of cams whatsoever.

I've been lookin through the summit catalo, and I found a comp cam competition cams K-Kits? Anyway, the cam I'm looking at (Summit part number CCA-K12-206-2) says RPM range 1,200-5,200. Duration@ .50" Int is 212 degrees, and Exh. is 212 degrees. Lift Int. is .440" and Exh. is .440"

Ok, so my motor. It is a 1988 350. Bottom end rebuilt. 305 TPI heads, headers, full exhaust, Weiand Stealth dual plane manifold, Carter AFB competition series carb. I put all the numbers into the desktop dyno, and this is what I came up with. I know this is power at the flywheel, and don't know how accurate it is...

 

Sorry, forgot something. It's either, with that combo (intake and cam) or I'm thinkinmg Edelbrock Performer RPB manifold with the cam that's supposedly dyno matched for it (accordin to summit). The cam has a lift Int. of .488 and Exh. .510 Duration Int. 234 degrees, Exh. 244 degrees

That actually, to me, seems like a better setup. But, with the heads I have now, who knows.

Also, if it matters, my car is a 5 speed, with whatever gears came stock I guess, 3.08's? Non G92 car...It's a convertible.

 

The Edelbrock performer RPM cam won;t work well with a 3.08 rear gear. Either increase the rear gar ratio or select a smaller duration cam.
With a 3.08 I would keep the duration under 218@.050"

You could/ should remove your heads and port them with larger 350 sized valves (2.02 x1.60).
They respond very well to this.
Then you'd get the top end your looking for from the edelbrock cam from a smaller more flexible cam choice.
Just adding a big cam is not going to give you the results you're looking for.
Everything has to work together.

 

I called a few machine shops and the lowest estimate I ot to port/polish the heads was just below $600. I just don't have that kind of money right now, with all the other money I dumped into this engine. With that said, what cam and intake would you recommend for my setup? also, any idea how much power it should be making?

 

Alright, here's the deal. There's a guy on here selling ported/polished 305 heads for $200. If I get those, is the edelbrock cam and intake a good choice? I really need to know. I want to order everything I need Monday morning so I can start putting the engine together.

 

What is the maximum lift those heads can take with a factory installed height?

I have the ZZ4 intake and Xe256 cam in my LG4 and it works real well. No need to ditch the Stealth just yet.

 

The edelbrock cam is crap, it is total trash, don't run it think or even think about. It's a big old baddly designed cam that will kill all power.

 

Oh yeah since you have a roller block get a roller cam, anything else is a waste of the block. An LT1 cam would work good and are really cheap $50.

 

I can't read your graph, so I don't know what it says; make the bottom half fill the screen, and the left half of that, and you'll have something useful.

Don't use the RPM cam, it's terrible. It may "run good" as far as that goes, and people will probably pipe up and tell you "I have it and it runs good"; it's just that something else will run a helluvalot better, and in adition most likely be alot cheaper and easier to drive.

The Comp cam you are asking about is an OK cam, but again, can be beat, especially when used with stock heads, for essentially the same money.

Find out if your motor is roller-equipped, or at least, has the provisions for it. If it is, get a roller cam. IMO the LT1 cam is too small and too compromised for fuel injection, to be the ideal choice for a carb motor; but will work OK for very cheap. If your block came from a truck or Caprice, i.e. a TBI motor, it may not have the provisions for the roller setup; but if it does, it's cheap HP to use it.

You need a cam with a bigger exhaust lobe than intake, because stock heads have better intake than exhaust flow, especially after porting. The bigger exhaust lobe helps equal things out. You can't jam more into the cyl unless you can get the spent gases out. A single-pattern grind like the old 260H you mentioned isn't the best choice because of that. Look at Comp's XE series, the XE262 specifically; or a similar design from Crane, Lunati, Crower, etc. In short, a top-tier cam grinder with a R&D department. Look at grinds that give 215° - 220° duration @ .050" on the intake, and about 10° more than that on the exhaust; all the lift you can get; and the lowest "advertised" (seat timing) you can find, subject to the variation among mfrs in how they measure that particular property of their cams.

Stick with people that do actual cam R&D, either in their own facility or by supplying professional race teams that count on their cams to be better than the guy in the other lane; and grind their own designs in-house, unlike Edelbrock, which simply re-boxes the same ancient generic grinds that you've been able to buy for the last 30 or 40 years. That "RPM" grind (and all the other grinds they sell too, for that matter) is available from every bottom-tier cam supplier on the planet that just copies and re-boxes for less money than Edelbrock charges, anyway. We've learned a little bit about how to make cars work better in all those years.

 

Sorry about the graph, it is really full screen but I have two monitors so when I press print screen, it combines the two. It doesn't really matter, I've been reading up on Desktop dyno and pretty much I've ot the assumtion that it's pointless to use because it's so inaccurate.

Anyway, I've been looking through my summit catalo for a cam with the specs. you suggested, and this is what In found...
A Crane cam RPM rane 2500-5500, Duration 222 derees/234 degrees, Lift Int. .467, exh. .494. What do you think?

Oh yeah, my motor is out of an '88 GMC van, It was TBI so I don't know if it has the provisions for a roller cam yet.

 

DD is well know to be hugely optimistic; but it is useful to see what changes as you adjust different parts. It's great for seeing the effects of changes even though the raw numbers it puts out aren't always very real world. The farther you get from a pure race car, i.e. the more of a street car it is, the higher its estimates tend to be.

That cam is the right sort of thing; maybe a step large, but in the right range. BTW, I would discount the "RPM range" thing, unless they give some kind of specs for what happens at those RPM extremes..... does the torque at those RPMs fall below 80% of peak? 50%? 25%? Do they merely mean that the motor will run? Do they mean you should gear the car such that you shift at the high one and come down to the lower one after shifting? And so on..... Without knowing what the numbers actually represent, take them with a grain of salt.

A van motor almost certainly won't have the roller provisions fully machined, although the casting will include them. It's possible but not very practical to DIY them in. Bummer.

 

So woiuld that cam be a decent choice or do you think I could do better? I filled out Crane Cams form on their website for a cam recommendation just to see what they have to say, but a lot of the information they asked, I don't know, so we'll see.

There is another cam they offer that I'm looking at, because you say the cam miht be to big. It is another Crane Cam, RPM Range (know you said it wasn't important) is 2,000-5,000, Duration 216/228, Lift .454/.480

Whaddaya think?

 

That's about the perfect one, out of their product line. The other would be OK but this one I believe would be better.

 

DD2000 or 2003 offer their best estimates when you enter the most accurate info you can and then subtract 5 or 10%. It will not be very far off at all when done like this and almost certainly won't be overestimating either hp or torque. But it is hp and torque measured at the flywheel with NO accessories running. To compensate for this you should minus about 30 hp and you will be really close to the actual numbers as a major manufacturer like GM would rate them

 

I have an engine out of an 88 pickup. Those aren't equipped with a roller cam but the block is a roller block. The trouble is, there are some holes that need to be drilled and tapped in the lifter valley and at the front of the block to accept the hardware needed to hold the roller cam and components in place.
It might be a PITA to do that, especially with the engine in the car. you'd have to be really careful about not getting metal shavings in the engine.
It's been done by quite a few guys here tho.

I have a feeling that yours is a roller block.

 

So out of those two cams I mentioned, which do you think I would be better off with. Keep in mind, I'd really like it to sound like I have a cam in the car. Nothin to extreme, just that lope at idle, you know what I mean?

Also, a long shot, but what do you guys think I should be making for HP and TQ with what I've listed?

 

I had one of those 216* Crane cams in one of my motors.
It was good, nice lope, pretty good top end, not much sacrifice in bottom end, good hwy MPG.
A stall converter isn't a must with that cam, but it's better with a higher stall.
Mine was the HMV 272, but they've changed the name of it now. Still the same cam though.
Never tried the bigger one.
I don't think you'd be unhappy with either.

 

Alright, so if I go with the 216* cam, is the Weiand Stealth intake manifold a good choice, or could I do better than that?

And my other question....What size headers should I go with? I've seen so many sizes and so many brands...

I just want a decent set for around $150. Any recommendations?

 

I went to summit to see about ordering the cam, and there was this warning:

1988-98 Chevrolet 305 and 350 V-8 engines (and some 1987 350 V-8 engines) use a different camshaft core configuration than the 1957-87 engines and cannot be interchanged.

Will this cam even work with my engine?

 

Yes it will work. Get it with the lifters that go with it.

That warning is referring to the factory roller cams.

I doubt you'll find a "decent" set of headers for $150. That's one of those areas where you definitely will get no more than what you pay for. Pay the least, you get.... guess what. In the case of headers, that means a set that doesn't fit well, isn't compatible with your accessory brackets, leaks no matter what you do, rusts out in a year or 2, requires "custom" exhaust work that costs more than the difference between the "cheep" headers and good ones, and otherwise has all the classic "cheeeeep header" problems.

You might want to watch the classifieds on this site, and pick up a used set of SLPs. Make sure you get their Y-pipe if you do that.

 

Any set that you could recommend that would be compatible with what I have?

(Also, I have a three inch flowmaster exhaust already, with the piece in front of the cat (towards the front of the car, have no idea what it's called) Anyways, that is also a three inch piece, so I'm guessing I'd need a Y pipe with a three inch end on it, correct?

 

If you want to simplify the job, shortys are the way to go.
They're inexpensive, easy to install, and they'll match up with your existing system.
Shortys aren't as good as long tubes, but they're an improvement over the stock iron stuff.
It sounds like you're going to have your hands full with your cam/ intake swap. If you feel like taking it easy on yourself (and your wallet) then shortys are an option worth considering.

 

Best way I know to get a set of quality headers for the best possible price. Just watch for a set in good shape, maybe coated even, with AIR tubes if you need them; with the Y-pipe of course. You can buy the right adapter for any sort of cat from SLP, as well as their install kit if you need it. I'd look for 1¾" ones.

Edelbrock TES is another good option. Nto as good quality as the all-stainless SLPs, but a very good fit and well engineered. They are only available in some smaller size, and so will probably not run quite as strong as the larger SLPs.

I would not recommend long-tube ones for a street car, even though they will produce the most power; the small power gain isn't worth the extra hassles they will certainly create, like hooking to a stock exhaust (the others will) and ground clearance and custom work expense.

 

About the headers:
Should I be looking for a pair that fits a thirdgen, the van, or it doesn't really matter?

Also, the no name brands on e-bay any good? (they're really cheap (priced) )

One last thin about the cam, If I get the bigger one, will the car still run right? Even if they make the same power, There's always the possibility of further mods that the cam might help? But I don't know anythin about cams. I would like to order it today, so any more info on top of what's already been given would be extremely appreciated

 

The headers need to fit the chassis.

As far as no-name headers, it's anybody's guess. But, see Rule #2 of Hot-Rodding: You get no more than what you pay for. Pay the least, get the least. If you've ever had to deal with a loud, leaky, plug-wire-burning, ground dragging, expensive to install, gasket blowing out, rusted through, set of POS headers before, you won't want to go back. If you haven't, then maybe cheeeep headers are for you.... just this once. Then you'll know why they're not as good of a deal as they appear. Like, when you buy the cheeeeep ones, and they're (let's say) $150 less than good ones, and you try to install them and you can't, so you take them to the exhaust shop and when you finally sweet-talk them into hacking them on, it costs you $225, and they have to trash your brand-new $275 cat-back in some irreversible manner to get them on; and then the very first time you drive up into your own driveway on your way home from the exhaust shop, they scrape the ground hard and smash half the tubes flat and bend all the rest to where they rattle against the chassis and the welds crack and they leak like hell for the rest of their few remaining earthly days, and then you get to go buy a new cat-back AND a set of good headers to replace them..... did you really get a deal? OBTW, see if you can guess how I know that this is how cheap headers work. But if you want to try to defy the inevitable, go for it.

 

Alright, I'll take your word for it, Just do me a favor and recommend me a good set that will fit with what I have, that isn't TOO expensive. I'm willing to pay, if it's reasonable.

Also, any thoughts on the cam?

By the way, thanks for all the help...I really appreciate it. I'm pretty much new to all this. That's why I kneed so much information.

 

As I said, watch the classifieds (and ebay) for a good set of SLPs, they're the best out there for street use. They make them in 1-5/8" and 1¾"; you want the larger one; and they can be had either with or without AIR tubes. The next best for a street application is the Edelbrock TES, which will also bolt to a stock-configuration exhaust in the stock location using stock hardware, but they are only available with smaller tubes.

When you buy the headers, get either the model (in the case of the Edelbrock) or the install kit in the case of the SLPs, for a 350 TPI car. DO NOT get the stuff for a TBI car, even if that's what yours was; if you do, you will be preserving the bottleneck in the exhaust, and voiding a major part of their benefit. In fact, if you can swing it, you might want to consider getting a new cat and cat-back exhaust at the same time, all for 350 TPI; that will assure you of getting the most out of your money.

As far as the cam, I think the slightly smaller one would be better, near optimum in fact, but the other would also be OK.

 

Alright, thanks a lot. I just ordered the smaller cam from summit. A good price in my opinion, at $159 for the kit.

I'll keep a look out for those headers, also. I already have a flowmaster American Thunder series exhaust for the car, about half a year old, so I'm not worried about that. High flow cat, and the pipe in front of the cat. So, All I need is the headers and a 3" Y pipe, correct?

One more quick question, sorry to keep bothering you, but are bolt on headers alright? I've seen that some have to be welded, I'd like to avoid that if possible.

 

This was posted in the classifides:

Used headers. Come with modified y-pipe (single pipe is all 3" now). Freshly bead-blasted and painted with high-temp black paint after removal from car. These are in great condition. Buyer pays actual shipping cost. $140 OBO Thanks Brady

What do you think?

 

One other quick question for you guys...

Sorry, I know it's dumb, but whats the name for a distributor that doesn't use a computer, you know the one you use with a carb?

 

Also, I'm goin to still be using the stock fuel pump (in tank, for TPI)....If I just put an AFPR in the fuel line, will that work with the carb? If so, any recommendations?

That will about complete the parts I need to do the swap. Cam came in today, so it's all good.

 

Yes the afpr will work as long as it has a return line. return line is a must, or else you will burn up the pump. The distributor you are thinking of is a GM HEI distributor.

 

Hey, just want some opinions on these items I'm thinkin about buying....

Distributor

Headers

 

The distributor is OK. I actually know some one who has the exact same distributor. BOught it from the same place. It a good piece. The headers though are another story. I would stay away for one simple reason. He said they were so rusty that he had to paint them white, and then didnt show any closeup pictures. My guess is that they are used up old worn out rusted pieces of crap. I think you could find better.

 

Yeah, those headers are pretty inexpensive new, from Summit or almost anywhere. And they should bolt up to your stock system if you get the right ones.
The headers are the cheap kind, but if you're aware of that at the time you get them, at least you won't be disappointed. And you can upgrade your system next season, after you have all the bugs worked out of the rest of your setup.
Believe me... there WILL be bugs to work out.

I've been doing my own auto repairs for more years than I want to admit, and when I did my first EFI/Carb swap, there was no end to the surprises.

 

i would pass on the headers. Note the fact that he said they were rusted so he coated them with high temp paint. And it's a crappy paint job to boot. It looks like header wrap at first glance to me. My money is on it burns off and reveals the high performance R.U.S.T. coating all over. Just save for new headers. They are cheap enough. Like RB said, wait for SLP. I have a set and am extremely pleased. Especially with their Y-pipe. Yes, the SLPs are pricey, however, their quality, IMO, is top notch.

 

Hey uys, just another quick queestion. Since my whole setup has already been discussed here, I just figured it easier then starting a new topic. Anyway, I need a quick response.

Is this too extreme for my setup? Or is it bettert than my Carter AFB competition series (600 CFM carb)

Carb + Intake

He wants $275 + $25 shippin to end auction early.

What do you guys think?

 

THe edelbrock q-jet is supposed to be a really good carb, and that is a really decent intake too. I think those carbs go for over 300 alone. So if it is really in good shape as the auction says, that is a good buy.

 

I wish I didn't have to spend this wks parts money on a set of recon'd rods.