tjtaylor

im building a 96-00 383 from summit racing. i was using my lunati voodoo cam in my 73 400 but i wiped the bearings somehow on it so i building a different block. my question is how much of a difference is there with the same spec cam but one is roller and one is not, the lunati cam only has 2000 miles on it. is it worth the upgrade?

vetteoz

iTrader: (13)

Yes
Same for same , a roller cam will act like a bigger cam because it opens the valves faster due to the faster ramps on the cam lobe
From Comp site

Flat Tappet vs. Roller Tappet Lifters

In nearly all circumstances, a good roller camshaft design will outperform its flat tappet counterpart. Among the benefits of roller cams are higher tappet velocity, more lift and more area, along with reduced valve train friction (often a 15+ hp increase) and higher engine rpm with little effect on low speed drivability and power.

Roller tappets are also reusable, which makes it possible to swap just the camshaft without the expense of new lifters. And finally, roller tappets are far less prone to wear, allowing higher spring loads, and they are more consistent with today’s oils.

The biggest advantage with a flat tappet cam and lifters is the upfront cost. It can be significantly less expensive to use a flat tappet setup but should you decide to install a new camshaft, flat tappets are not reusable. You will need new lifters as well.

A good read
http://www.myrideisme.com/Blog/camsh...pet-vs-roller/

Guest

It's really cheaper to just start out roller. The salvage yards charge the same for late blocks as for early, late blocks mostly don't need overbored, you don't have to buy special oil and ZDDP additive, you don't need low-tension break-in springs, you don't have to do an oil and filter change after the first 20 minutes, you don't have to use special oil at each oil change forever after.
Plus the roller will give more lift, where the flow is, and more duration-at-0.200" lifter lift, for any given at-0.050" spec.
With a stroker, you need that extra window area.

Sonix

iTrader: (1)

Yea, what he said!
I used a handful of flat tappet cams in my engine, and i'm happy with them. That being said, of the 3 i've tried, I did wipe one out The cost is low, but you're leaving 15-20HP on the table, right off the bat. If you have an old block, and would have to use "retrofit rollers", you're looking at ~$600+ for the cam and lifters, compared to ~$200 for the whole setup. In that case, may as well go flat tappet. $400 can probably go elsewhere. However with a newer block, i'd definately use a roller cam. Unfortunately it's hard for you to sell your old flat tappet cam to recoupe the cost
PS- Anyone want a lightly used good shape compxe268HE ?

tjtaylor

thanks guys for the fast responsesm ill read that website in a little bit. ya the block im buying is summits reman 355 or 383 clearenced for 3.75 stroke with h beam rods, which i already have. i just wanna get my car on the road and that roller cam set up puts me back another paycheck also i matched my springs with my lunati cam and im not sure they will work on the roller cam set up will they? i mean i dont know the bind rate off hand but are flat tappet springs different from roller springs??

ASE doc

Roller springs are higher silicone content to tolerate the higher ramp velocity of the roller lobes. When specking out springs you need to specify roller or not. I understand that you want to get your car running but think about what you're investing here. You can do it right the first time or end up later wishing you had.

dimented24x7

iTrader: (2)

The spring rate and open/seat pressure are major factors with roller vs. flat tappet. Hydrolic roller lifters are about 60% heavier than similar flat tappet ones. Youll need to run a heavier spring with a roller. Really it all depends on what the cams profile is and what else is in the valvetrain.

What springs do you have currently?

dimented24x7

iTrader: (2)

Also, is your block going to need a retro-roller? You have to be careful which lifters you use. Comp has had a checkered past with ther retro-lifters. Some have had the roller wheels come apart, while others have had the link bars eject right off the lifters. In both cases, its instant destruction. I got a set of comps, and whoever they selected to produce them made a product that was complete crap. Many of the retro-fit guys use Morel lifters. Theyre a bit noiser than stock hydrolic roller lifters, heavy as hell, and are $$$, but they do seem to withstand the test of time from what I hear. I bought a set and they where very well made. Everything was nicely machined and the bearings in the roller where super smooth.

Dont simply select the cheapest ones you can find. You may regret it.

tjtaylor

i dont think i need a retro roller, i thought all new blocks mine is somewhere between 96-00 is a roller motor. here is what im buying.
http://www.summitracing.com/parts/SUM-150100/

this is what i have
http://www.summitracing.com/parts/LUN-60104LK/
http://www.summitracing.com/parts/CCA-986-16/
http://www.summitracing.com/parts/CCA-740-16/
http://www.summitracing.com/search/?...cca61116&dds=1

so im gonna need a new cam and springs as well if im going to do the roller cam.

vetteoz

iTrader: (13)

If you already have the FT cam , valve train and heads setup for it ,you can just install all those in the new roller block with a non roller timing set.

Then swap to roller cam later when you have the $$$.

Al Weyman

Just think why GM stuck rollers in the small block for your answer. It gave better fuel economy so they could meet the CAFE figures. It also means lower oil temps. A guy over here who runs a Dyno and specialises in chevy and ford v8's told me that a flat tappet cams frictional losses alone can add up to quite a few BHP that you will loose over a roller. BTW once you have gone roller you can run a lighter fully synthetic oil so more plusses.

tjtaylor

good news guys i drove to summit racing today (only ten minutes away, whose jealous lol) and was looking up roller springs in stead of flat tappet and turns out i already have them! im good up to a 540 lift, so anyone wanna give me a good grind for a 383 thats somewhat streetable? particular brands anyone? to buy or to stay away from? thanks

vetteoz

iTrader: (13)

What compression in engine?
What heads (flow ) ?
What intake?
What gears and stall?
How do you drive?
Need fuel economy?

All those define what cam will " work" .
No point putting in a 6K+ cam if intake / heads restricts engine to 5K

tjtaylor

the engine is about 9.8 maybe 10 im not sure how much theh shop decked the heads. the heads are procomp heads with 202 and 164 i believe, 200 cc intake runner 65 in exhaust, idk the flow of them. intake right now is summit stage 2 but i want a single plane. gears are stock 3.08 and its a 5 speed. i have a heavy right foot. well i had 24 mpg on a carburated 400 going out to thirdgen fest this year and that was kinda nice.. but not totally needed. my cam before was lun60104lk from summit it had 504 525 lift 233 241 dur 110 lsa it was 2200-6400 and i think it was just about right but idk what this 383 is gonna rev too..its a balanced all forged rotating assembly.

InfernalVortex

iTrader: (4)

I run Mobil 1 synthetic with a flat tappet cam. I use a Zinc additive in it, though.

tjtaylor

thats not what i asked

TreeFiddy

Same cam as mine, how long has XE262 + Mobil 1 + zinc been working for you?

InfernalVortex

iTrader: (4)

DIdn't mean to quote you, sorry.

To answer your question, it depends on a LOT of other factors. For streetable... I'd look for something modern, Comp XR or the like, and go with something in the 230/230 range. Go 240/240 if you've got a compression ratio around 10:1 with iron heads, 10.5-11:1 with aluminum heads and soem decent 190-210cc intake ports. You said "somewhat streetable". 220/220 will be very mild in a 383 and still make decent power. Probably at least 300 to the wheels if the heads are decent. a 230 to 240ish cam will make a good bit more power and be a good bit raunchier... bigger cams need better combos though. What heads do you have? Intake? Gears? Converter? all these matter. Its easier to get away with smaller cams if something else isnt set up optimally. If everything else is set up right, you can get away with very large cams.

A little over a year now. I run half a bottle of Comp break in additive every oil change. I ran conventional with full bottles of break in additives for the first 5k miles.

tjtaylor

read post #14 i answered all those there. i want way more than 300 to the wheels.

InfernalVortex

iTrader: (4)

You need 3.73s.

I'd go all out... 240/240ish duration. You'll have borderline vacuum, so you may need to do something about your brakes, but I think you could pull it off.

Al Weyman

I have a seriously nasty roller in my older 2nd gen car too nasty really as it doesnt start singing till over 4000 rpm but I can honestly say I have never had a brake vacuum problem on that or the third gen which is also pretty stout and that has a Victor Junior manifold. Maybe because I keep the thing buzzing as its a pure race car.

tjtaylor

al weyman, you happen to wanna share the grind on ur cam so i know what is"too much" lol

Infernal vortex, you dont think that the 373 will make me lose a gear ? is it worth the upgrade? i know i went from a 355 in my dakota to a 410 gear and it made quite a change in my rpms. it wouldnt matter to me much if i had a t56 but i dont

vetteoz

iTrader: (13)

Wouldn't be much different.
T5 has similar ratios to a T56 except T56 has a extra O/d gear

http://www.chevymania.com/tech/trans-ratios.htm

Al Weyman

There was some confusion as I bought the nasty cam from UK engine builder Peter Knight of Knight Engineering secondhand. When I checked out the numbers on it I contacted the manufacturer who told me it was a drag cam and wouldnt work under 6000rpm. They took so long getting back to me I had already installed it and found in fact it pulled strong from about 4000rpm (see video) so was somewhat confused. I got back to Peter who told me dont take no notice of the grind numbers as he specified his own grind and they were not relevant and that he had fitted the cam in a 1/4 mile oval UK style stockcars and the guy wanted a greater spread of power. So to cut a long story short I dont know the grind however...... I do know the figures for my 3rd gen car and that has a sweet band of power and I recon could be occassionally street driven, I also changed the springs thatthe original builder used as I felt they were way over the top and I now use the K200's I think they are called. They seem to work fine and have probably released a bit more power, I rev to 7000 on occassions but not really necessary.

Cam spec @.050" lift
Intake open 26 deg BTDC
Intake closes 54 deg ABDC
Lobe Center 108 deg
Lift Duration 260 deg
Lob Lift .390"
Gross Valve Lift .585"
Rocker Ratio 1.5-1

Exhaust Opens 66 deg BBDC
Exhaust Closes 24 deg ATDC
Lobe Center 110 deg
Lift Duration 270 deg
Lobe Lift .410"
Gross Valve Lift .615"
Rocker Ratio 1.5-1



The video below is from the 2ng gen car with the nasty cam. This is at a very tight track that doesnt suit these cars but is a good example and you can see the rev counter clearly and notice its a bit flat under 4000rpm and really starts singing at 6000 plus, not streetable!! http://www.youtube.com/watch?v=4Lz7C0hI7Mc

InfernalVortex

iTrader: (4)

If you have a .73 OD gear (they had .76, .73, and .67 in 91) then 2500 RPMs would be 70mph. So it wouldnt be awful....

http://www.kabamus.com/garage/gears.html

If you've got a 383 making over 300 hp, the T5 is not going to hold up. Period. Plan for a T56. The wcT5 is only rated for 300ftlb of torque if I remember right, and that's a limitation of the transmission case, not the gears or anything else. The case flexes because it's a weak limp noodle, and the gears and shafts bend and flex into each other at weird angles causing the problems. The T56 is rated for 450 ft lbs I think. It will last you a little while though probably so dont fret about it ahead of time. Just dont buy a spohn swap crossmember. Those things are awful.

Anyway, i've got 3.27s and with the tall first gear of the T56, my car is a dog off the line or from a stop. It's awful. As soon as you get rolling the wide power band of my relatively small cam kicks in and gets it rolling and it's a lot of fun. If you have a big cam it's much more important to have proper gears. The power bands just dont match the gear ratios well. If you're gonna go with a behemoth cam (which I think isnt a bad idea. you have most of the supporting mods and hardware for it. The 383 tames massive cams on its own) you need a rear gear ratio that will allow you get the car moving from a stop without toasting the hell out of your clutch every time.

The problem then becomes... do you put money into the 10-bolt by doing the gear swap or rear end swap... even though you're making more than enough power to break it like it's made of porcelain? You might want to look into getting a used 9-bolt. But you'll need to find one from 1989 to get the decent rear disc brakes. And you'll need to make sure they're 3.27 or higher gears, or else you'll need a new carrier for decent gears, and decent gears cost decent money for 9-bolts. 9-bolts are a lot stronger than 10-bolts, but you're still living on borrowed time with one with a big cammed 383. I do think the 9-bolt would last a lot longer under that sort of abuse though. But it wouldnt be a permanent solution. The 9-bolt would outlast the T5 though.

Also, as far as what gear ratio... if you can get something with 3.42/3.45's that would be fine too. 3.73s would be preferred, but 3.42s would be a vast improvement over the 3.08s you have.

Al Weyman

I agree with above ref gear ratios. I have a 4 speed M21 in my 2nd gen and the 1st gear is absolutely ridiculously long even with a 3.5 diff you are talking over 70mph in 1st gear. after that the ratios are very very close in fact I read somewhere its the closest ratio box ever fitted to a road car and I can believe that. I am having a bit of syncro trouble with the M21 in the 3rd gen car with the much flatter cam so while waiting to rebuild it I stick a spare M20 wider ratio box in it (a passenger car version not truck so not too bad). Anyhow the gearbox seems to suit the cam better than the M21 but I know for a fact wouldnt work in the old 2nd gen car with the nasty cam.

tjtaylor

well see i thought the same thing about my t5 when i built my sbc 400. it had all the same internals this 383 is going to have, like heads intake cam and carb. its still pretty tight and i did some light beating on it i would say. if i had the money i would do a t56 swap but i dont right now ugh. whats the normal hp/tq a 383 makes? is there like a given that is usually isnt under a certain amount? just curious. i was shooting for 400 or up..

yeah agreed i think the only reason my 10 bolt hasnt exploded yet is because its an open rear end. i was looking at moser's rear ends thats cut for our cars but thats a big chunk of change when you add in the case and third member over 2500.

InfernalVortex

iTrader: (4)

If you drive it a certain way the T5 may live. It isnt rated for it, but it's all about shock loads and that has a lot to do with how you drive.

I like to assume a healthy SBC will make 1hp and 1tq per cubic inch.

You will very likely make more than that if you get a 240/240 ish duration cam.

Dustytrix

iTrader: (3)

LT4 Hotcam, I know I will get dogged for the suggestion but its proven itself many times.Also I would not use a single plane intake unless your way up in rpms, and in that case the lt4 wouldnt work anyway. jm2c

InfernalVortex

iTrader: (4)

LT4 hotcam is a great cam, the only problem is that you have to remember the specs on it are with 1.6 ratio rockers, not 1.5. So it's not as "big" as it is portrayed. As long as you keep that in mind it's an excellent cam.

tjtaylor

is comp cams normal roller cams good? you had said that the retro rollers the lifters break but what about normal rollers?

ASE doc

The "retro" part of the roller cam kit is the lifters. Roller cams have been used in racing for decades using the same style of lifter, generally a link bar, as the current retro style lifters. Until the OE began producing hydraulic roller engines, we didn't have the spectacle or dog bone type anti rotation links used in production roller cam engines. If you're concerned about the strength of the comp cams roller lifters, go to Howards or Jezel or Isky or any one of the many other manufacturers of roller lifters. Just remember the difference between hydraulic roller and solid roller. One is self adjusting and absorbs harmonics in the valve train. The other isn't and doesn't.

MaxpowerTA

I'm gonna chime in here on the subject of the T5, "If you've got a 383 making over 300 hp, the T5 is not going to hold up. Period" This statement simply is not true and I've seen this myth spread all over this board. I have run a WCT5 in my T/A for years at above 300hp levels and I do not "baby" it and have no issues. I also personally have 2 friends with who road race fox body mustangs with stock WCT5's and they are pushing 450+hp and thrash the hell out of them with full throttle acceleration in the straights, up/down shifting at high speed etc and have been running for years without blowing them up. I think The key here is are you going to "shock load"on a regular basis like in a drag racing launch application. If you drag race it and use sticky tires and actually hook up then yeah you will break it, but if your using it in a street application it is a good, reliable transmission even at well over it's factory torque rating.

dimented24x7

iTrader: (2)

The cams from comp are good. I mentioned this in another thread as well that Comps hydrolic lifters have had a checkered past. Some guys on the GN forums have had them come apart and take out whole engines. I bought a set and they where complete trash. The box was filled with metal shavings, the rollers where jammed, the rivets on the linkbars where iffy. Not sure how good they are now, but it left a bad taste in my mouth. I bought a set of Isky (Morel at almost 2x the cost), and it was night and day quality wise, and are nice and quiet once theyre set up just so. The only bad thing I have to say is that theyre really fickle about their lash setting and oil viscosity. The plunger needs to be in the middle of its travel and they need at least 5W-40 as theyre an anti-pump up design. They act like rhoads lifters if not set right as the plunger is designed to bleed down for the first 1/3 or so of its travel. Cant just set them at a 1/4 turn or with the motor running like a stock lifter.

If your using a lower lift cam and a roller block, you can just use the stock lifters. Theyre just as good, but at a fraction of the cost. The main limit there is that the dogbone limits how much lift as well as how small a base circle you can have.

tjtaylor

i was hoping to run a 240ish duration with about 540 lift, how much does the dogbones restrict to and why? to what extent can i use stock replacement roller lifters? i still need to find out if i even need small base circle. tonihgt i assembled the crank into the block and got all my rings on the pistons. tommorow i will be putting the pistons into the block and checking to see if my flat tappet cam i have now is going to hit any rods to see if i need small base circel.

InfernalVortex

iTrader: (4)

It will break. If the T5 cant even handle a stock L98 why on earth do you think a high horsepower 383 is fine? Probably has more to do with shifting technique and driving style than any inherent strength in the T5... which there is none.

Mustang T5's are different situations than F-body T5s anyway.

dimented24x7

iTrader: (2)

There are two restrictions with the dogbones. The first is obviously the lifter must be high enough to engage the dogbones to work. With a small base circle cam, the top of the lifter can be below the dogbone. The next issue is the max lift. If the lifter comes up too high, the slotted portion will bottom out in the dogbone and force it up, which would potentially cause a lot of damage. I dont know offhand what the limits are with the stock valvetrain, but Id imagine that .540" would be pushing it.

With that kind of lift, your better off just running a solid roller IMO. With high lift and higher spring pressures, the hydrolic lifters can bleed down due to the high loads and cause a loss of lift and noise. If you use rockers like comp pro magnums, you will essentially never need to re-adjust the lash once its set initially as there really isnt anything to wear and open up the lash in the valvetrain.

tjtaylor

hmmm well i assembled my short block tonight and threw my flat tappet cam in with 233 241 dur and 504 525 lift 110 lsa and it didnt hit the rods at all i think. obviously it would get to a hard point if it contacted it right? will it have a better chance of hitting my rods when it gets to running because of metal heating up and possibly expanding?
so now im stuck in a pickle cuz id like to run a roller cam but i would havr to see if that one would clear to before stepping to a sbc cam. thats alot of cash..and i dont have dog bones or anything yet, id have to purchase them and the spider thing to hold them in place. any other ways to go about a sbc cam and high lift with out using dogbones? im new to roller stuff

dimented24x7

iTrader: (2)

I dont know what your currently working with, but its worth mentioning that the dogbones and spider will only work with an 87+ roller or truck block as they have deep lifter bores and bosses on top of the cam bearing oil passage to accomodate it.

If you do a solid roller, you can run a small base circle cam and the less expensive solid roller lifters. Given the issues with flat tappet cams in the long run, I would say that its a good investment up front while your building the engine.

tjtaylor

it is a 96-2000 roller block already it has the bosses for the dog bones and holddowns. now you said the dog bones have a restriction, but this kit includes everything id need. http://www.summitracing.com/parts/EDL-22046/ does that mean the lifters wont be a problem with the dog bones? and how good is edelbrocks cams?

Dustytrix

iTrader: (3)

[quote= and it didnt hit the rods at all i think. obviously it would get to a hard point if it contacted it right? when it gets to running because of metal heating up and possibly expanding

You will need to rotate the engine at least 2 complete revolutions with timing chain and cam installed to find out if it hits. Even if it doesn,t you still need about .0060 clearance between rods and cam, rods and block.

tjtaylor

okay i will check that but i went out and bought a roller cam today. its a comp cam http://www.summitracing.com/parts/CCA-08-433-8/ what do you think? i think it should be a good rpm range for the 383. but unfortunatly i was examining the cam bearings today and only one of the five oil passage holes in the cam bearings are lined up corrrectly. this was summits reman 355 or 383 block with cam bearings and freeze plugs installed already and they messed it up. way to go summit!!

InfernalVortex

iTrader: (4)

Complain to summit and see what they say about it.

That looks like an excellent cam to me.

dimented24x7

iTrader: (2)

Where are the holes located? With the block upright and looking at the front of the block, the oil holes should fall between 12 and 4 o'clock and centered over the groove. The ideal location is about 2-3 o'clock, but any position between those points will work. From what Ive seen, aftermarket GM blocks have the front bearing oil holes located at 12 and 4 o'clock, and the rest at 12 o'clock. No oil hole should be located between 4 and 8 o'clock.

tjtaylor

the front oil hole was correct with it being about six o clock if looking at it from the front. all the rest were off to the right about 4 or 5 o clock. i did call summit and they said theyd riemburse me for the work. its just a pain having to wait though..i took it to a local machine shop last night and my buddies dad who owns the shop looked at it and was shocked that he could see block on the other side of the hole and not another hole.

dimented24x7

iTrader: (2)

No cam bearing holes should be between 4-8 o'clock positions. Aligning them with the feedholes ok back in the 50's, but with high spring pressures its essential that no holes be at the bottom of the bearings. This is because the oil film that supports the cam is there. The pressure within the film is actually much higher than oil pressure (up to several thousand PSI) as its the viscosity of the oil and its resistance to being pressed out that supports the load, and not the pressure. Any holes there will allow the oil to escape and cause rapid wear of the bearings.

To keep it easy for the machine shop, you can just tell them to put the front one at the 12/4 o'clock and the rest at the 12 o'clock positions.

tjtaylor

okay got it fixed sweet, now im on my way to finish assemblying this motor. should be in by the weekend