formula_novice

iTrader: (1)

Hi Everyone,
I'm looking to put a 383 short-block in my Firebird to replace my tired 350. I'm going to keep the heads, TPI, etc in my sig below. I spoke with a rep at Comp Cams and they recommended cam 12-256-4 (specs are Xtreme Energy Hydraulic Flat Tappet Camshaft and Lifter Kit Lift: .449''/.456'' Duration: 256/268 RPM Range: 1200-5200). My goal is maximum low-end & mid-range Torque and Horsepower. Do you all agree that this cam is a good fit?

Any input would be greatly appreciated!

Thanks.

1989GTATransAm

iTrader: (3)

No, No and No. Why don't you buy a short block set up for a roller cam? You already have a much better cam than what Comp Cams recommended and way better suited to a 383. Use the ZZ4 cam that you already have.

formula_novice

iTrader: (1)

Thanks for the input 1989GTATransAm!

I was opting for a 383 short-block because BluePrint Enginges offers them at less cost than a ZZ4 short-block.

I spoke with TPIS and they are recommending their cam that is...
Advertised duration 280 280
Duration at .050 224 224
Gross lift .495 .495
Lobe separation 112

Also, I'm running 1.52 RR, so the .495 will actually be .501.

This seems like a better cam than the comp cam one. You agree?

1989GTATransAm

iTrader: (3)

I went to Blueprint engines and checked on the 383 shortblocks. They list the BP-3837 and from the picture looks to be a roller block. Yes the TPIS cam is a lot better but I bet the price is high.

Orr89RocZ

iTrader: (20)

if its a roller block then thats great to have and there are LOTS of great cams for your combination

i'd recommend bigger heads, like the 200's. especially the platinum series as they flow abit better. dart heads are alittle weak on the exhaust side, so i'd use a split duration cam.

ZZ4 is great for a 350 but it will be very lazy in that 383. you'll want to go bigger. CC305 cam which is 220/230 and .510 lift with 1.5 rockers i believe is a nice choice. 114lsa so it will idle smooooothly. they also have a 224/230 cam, known as the 503 cam on a 112 lsa. the other version is the xtreme energy 276HR grind which is same duration but on a 110 lsa. I'd stick with the 112.

those would be good 383 TPI cams for decent performance.

Else you could look into the comp XFI series and go with the 268 grind which is 218/224. fairly mild for a 383. next size up off the shelf is 230/236 which may be a tad large. you could custom order the 224/230 grind on the XFI lobes. it would be a nice cam too but for your combo, it be cheaper to use the 503 or 276 cam that they offer off the shelf. I think custom grinds are abit more dollar

GM makes the 846 cam which i believe is like the cc305 cam from comp. its got more lift i think.

SLP got some nice cams too within the 218-230 duration range.

For maximum performance and power, i'd get better flowing heads and a 230/236 ish cam. for what you have and good performance, i'd keep intake duration around 220-224 and run 6-10 more degrees of exhaust duration split

formula_novice

iTrader: (1)

The TPIS cam isn't too bad at $185 (atleast for TPIS prices).
Blue Print BP-3837 is a roller but unfortunately its over $2900.xx.

Thanks a million for the info 1989GTATransAm and Orr89RocZ!!!

1989GTATransAm

iTrader: (3)

Which Blueprint motor were you looking at? You might be better off getting a 383 rotating kit from someone and use your block.

formula_novice

iTrader: (1)

I was looking at BluePrint motor BP3830.

I talked to a rep at Crane Cams and he recommended flat tappet
Part Number: 113522 Grind Number: Z-268-2

.459/.486 218*/230* (using my 1.52RR, it would be .465/.492)

This seems a little worse on the intake-side than the TPIS cam?

1989GTATransAm

iTrader: (3)

Regarding flat tappet cams you might want to take a good look at the Lunati Voodoo series of cams. They were designed by UD Harold one of the best in the industry.

Orr89RocZ

iTrader: (20)

i second the voodoo series.. i have heard good things about them. I dont know much about flat tappets. i guess the roll of thumb from what i been seeing is that it takes a larger flat tappet to make the same power as a roller. since flat tappets dont give as much lift they need more duration.

So i'd stick with a higher 220-lower 230 duration range flat tappet. comp also makes a XFI series in flat tappet. I'd check them out as well as Lunati. The XFI is a really aggressive flat tappet with alot of lift. i really like the 268 grind they have...224/231 on a 113 lsa with .520/.515 w/ 1.6 rocker. they say 2000-6000 rpm power band but probly 1500-5500 on a 383 so thats perfect for modded TPI.

you can try comps high energy 268H cam..its a 224/230 on a 110 lsa. they also make it on a 114 lsa for more friendly idle and computer tuning.

i'd go a little more on the intake side and just a tad more on the exhaust i'd say, but thats not a bad cam

formula_novice

iTrader: (1)

Hi guys,
I spoke to a rep at Lunati about there Voodoo cam series. They recommended the 60101 cam which specs as follows....

* Advertised Duration IN/EX: 256/262
* Duration @ .050 IN/EX: 213/219
* Gross Valve Lift IN/EX: .454"/.468"
* LSA / ICL: 112/108
* Valve Lash IN/EX: Hyd/Hyd
* RPM Range: 1000-5500

The rep said it was an "excellent cam for a 383 TPI". Do you agree?

Thanks again!

Orr89RocZ

iTrader: (20)

i think its alittle small...i'd go abit bigger

formula_novice

iTrader: (1)

Hi Guys,
One last question I read all your advice and started digging through my parts catalogs and found an interesting Blue Racer cam and the XFI mentioned above...


1) Crane Cams Blue racer Cam 290*/300*, 224*/234*, .465"/.488"

2) Comp Cams Xtreme XFI Cam 268*/280*, 224*/230*, .479"/.480"
(This is the one Orr89RocZ referred to above)

Of these two cams, which do you think would be better for the 383 TPI (going for strong low & midrange TQ & HP)? As I mentioned earlier, I will be using my existing 1.52 RR, so the lift numbers will end up being slighly higher than listed above.

Thanks a million for all the info!!!

1989GTATransAm

iTrader: (3)

The cam behind door number 2. The seat to seat duration is smaller so that it will idle better. The .050" lift numbers are very close. I would suspect the numbers at .200" lift favor cam number 2.

formula_novice

iTrader: (1)

Hi Guys,
I ordered Xtreme Energy Computer Controlled XE268H Cam
PART #12-268-4 today.

Thanks again for all the info!!! It is greatly appreciated!!!

Orr89RocZ

iTrader: (20)

let us know how it works out. i think that will do fine in that motor