tbi cam selections

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12-16-2014
Tylerz281500

tbi cam selections

Ive run both of these cams in totally different motors, i know of many builds using both as well but as far as preference between the two im unsure which would be optimal as i have both. My motor and trans went so the motor from my 72 is being donated, basically vortec bottom end, shaved 882's(not keeping as compression isnt ideal) lt1 cam, dual plane, ls9 springs. as for the motor i have currently is uses a summit 421/444 cam, nothing special but has done me very well, my tbi heads are redone and heavily reworked but once again nothing special and still tbi heads, performer intake which i could care less about roller tip rockers and tbi mods. Id like to know peoples preferences between the 421/444 cam and an lt1 cam, specs are close and ive liked both in the past, just a little more insight would be nice.

Ideally id like to get rid of the 193 heads altogether and go with vortecs or i can try to snatch a set of worked 083s and a carb intake, just depends on budget. trans is being redone at the same time, full rebuild slight stall converter, servos and transgo hd-2 kit and .5 boost valve as of right now. its my daily, ive been getting decent mileage (13 if i stay out of it) for a lifted truck.

Any help is appreciated, my post might be a bit confusing my heads in multiple places right now so i apologize and thank you all in advance.
12-17-2014
Fast355

Quote:

Originally Posted by Tylerz281500

Ive run both of these cams in totally different motors, i know of many builds using both as well but as far as preference between the two im unsure which would be optimal as i have both. My motor and trans went so the motor from my 72 is being donated, basically vortec bottom end, shaved 882's(not keeping as compression isnt ideal) lt1 cam, dual plane, ls9 springs. as for the motor i have currently is uses a summit 421/444 cam, nothing special but has done me very well, my tbi heads are redone and heavily reworked but once again nothing special and still tbi heads, performer intake which i could care less about roller tip rockers and tbi mods. Id like to know peoples preferences between the 421/444 cam and an lt1 cam, specs are close and ive liked both in the past, just a little more insight would be nice.

Ideally id like to get rid of the 193 heads altogether and go with vortecs or i can try to snatch a set of worked 083s and a carb intake, just depends on budget. trans is being redone at the same time, full rebuild slight stall converter, servos and transgo hd-2 kit and .5 boost valve as of right now. its my daily, ive been getting decent mileage (13 if i stay out of it) for a lifted truck.

Any help is appreciated, my post might be a bit confusing my heads in multiple places right now so i apologize and thank you all in advance.

Up through 4,500-5,000 rpm you really can't touch a nice set of worked over TBI heads. With the mild cams you have in mind there really is no benifit to stepping up to Vortec heads. The 083s would flat out be a waste of time. The TBI heads are better than the 083s. The LT1 cam works quite well, I actually prefer it to the 204/214 grind you mention due to the fact it is a roller grind, but either would work well.
12-17-2014
Tylerz281500

Really on the tbis? I might swap my ls9 springs to whatever i use but the 083s are a freinds and flow work showed the basically outflowing 113s not of cours its somewhat subjective. Vortecs i think your right are a bit overkill but still id sorta like a somewhat better head. But jeeping them is cheaper. As for cans the lt1 is in the motor right now so i can just lesve it in and relog my computer afterwards if i can get my laptop to recognize the cable. Just thought there may be a big difference from someone else opinion. Both i feel are great for tbi so i have no issie running either
12-17-2014
Fast355

Quote:

Originally Posted by Tylerz281500

Really on the tbis? I might swap my ls9 springs to whatever i use but the 083s are a freinds and flow work showed the basically outflowing 113s not of cours its somewhat subjective. Vortecs i think your right are a bit overkill but still id sorta like a somewhat better head. But jeeping them is cheaper. As for cans the lt1 is in the motor right now so i can just lesve it in and relog my computer afterwards if i can get my laptop to recognize the cable. Just thought there may be a big difference from someone else opinion. Both i feel are great for tbi so i have no issie running either

With a lifted truck you want TORQUE and alot of it. With the lift I am assuming you are running a larger all terrain or mud tire of sorts. I would recomeend regearing if you have not already to atleast correct your overall gear ratio. Proper gearing can make your transmission live a much longer life and help your acceleration. The 083s may flow a little better but there are other things to consider when you are building torque. Burn rate, port velocity and low-lift flow are what really drive low-midrange torque and the TBI swirl ports are great at all three things. Under .200-.250" lift the TBI heads actually flow substantially better than vortecs. With a mild cam you don't spend nearly as much time over .200" as you do under .200".
12-17-2014
Tylerz281500

Quote:

Originally Posted by Fast355

With a lifted truck you want TORQUE and alot of it. With the lift I am assuming you are running a larger all terrain or mud tire of sorts. I would recomeend regearing if you have not already to atleast correct your overall gear ratio. Proper gearing can make your transmission live a much longer life and help your acceleration. The 083s may flow a little better but there are other things to consider when you are building torque. Burn rate, port velocity and low-lift flow are what really drive low-midrange torque and the TBI swirl ports are great at all three things. Under .200-.250" lift the TBI heads actually flow substantially better than vortecs. With a mild cam you don't spend nearly as much time over .200" as you do under .200".

Since my ownership im geared properly and all that. So nit worried abojt that as well as every cooler possibke, trans, steering, oil
12-17-2014
Tylerz281500

also as recomended port and polish as well as some boring isnt a bad idea for tbis, should i also swap my ls9 springs? the ones on it now are basic replacement springs for all i know.
03-06-2015
rstroh

you dont want to port and polish the heads, thats only good for high rpm. you need the fuel to atomize efficiently and evenly so it needs to tumble around, cleaning the rough edges in the bowl area with a die grinder and carbide is a good idea. polishing just allows the fuel to slide; in high performance motors that need fuel quickly that works.

one cam i really like using for tbi motors is a comp 08-525-8 (800-5000rpm, 194/206 @.050, .470/.464 w/ 1.5 on a 116 LSA) gives great torque for a lifted truck with a small block and so pretty great fuel economy. i currently have that in my motor as well. its a roller cam, really the best way to go.

there's no need ls9 spring, and by ls9 you mean beehive springs? generally for these applications they dont provide enough spring pressure, even though comp cams suggest them too, they're definitely smoking something good. stock style replacement small block springs, either a 1.250 or 1.437 diameter (whichever your head is cut for) and installed height of about 1.700 with 120lbs on the seat and open pressure of about 320lbs.

I get to play around all day, i run a machine shop here in NY, working on opening my own soon. id be more than happy to assist in blueprinting if need be!
03-06-2015
Tylerz281500

Quote:

Originally Posted by rstroh

you dont want to port and polish the heads, thats only good for high rpm. you need the fuel to atomize efficiently and evenly so it needs to tumble around, cleaning the rough edges in the bowl area with a die grinder and carbide is a good idea. polishing just allows the fuel to slide; in high performance motors that need fuel quickly that works.

one cam i really like using for tbi motors is a comp 08-525-8 (800-5000rpm, 194/206 @.050, .470/.464 w/ 1.5 on a 116 LSA) gives great torque for a lifted truck with a small block and so pretty great fuel economy. i currently have that in my motor as well. its a roller cam, really the best way to go.

there's no need ls9 spring, and by ls9 you mean beehive springs? generally for these applications they dont provide enough spring pressure, even though comp cams suggest them too, they're definitely smoking something good. stock style replacement small block springs, either a 1.250 or 1.437 diameter (whichever your head is cut for) and installed height of about 1.700 with 120lbs on the seat and open pressure of about 320lbs.

I get to play around all day, i run a machine shop here in NY, working on opening my own soon. id be more than happy to assist in blueprinting if need be!

i did minor port in a sense that i did exactly as you suggested, never heard of the comp cam, im liking what i see so far though. i havent had an issue with ls2/6 springs yet i dont rev super high though either or beat on my stuff a ton, it is a lifted truck after all. ive never looked into blueprinting anything, id be interested in knowing more. i like building motors and know i have much more to learn.