Gonna be doing a turbo setup real soon along with a custom intake plenum. Was wondering if I could use the twin 48mm(think thats right) Instead of the stocker?? I figured that Im gonna be pushing alot of air threw it anyways so why should CFM matter at that point. Im probably wrong but its on my mind and need help/opinions. Thank you, Baron

 

with a custom plenum its possible, i was thinking of doing the samething but with a aftermarket tb with bigger intake bores

 

Jerriko did one like that already (welded a section of a TPI intake into the stocker). I did a search, but all the links are dead.
Why not use a monoblade? Thats what I did on Redraif's Trueleo intake. Hopefully we'll be able to post pics (and dyno #s) soon...going tomorrow night!

 

Pics, NOW!

Good luck tommorow

 

Well I can get a TPI one cheaper. But will all the hookups work?? TPS and IAC??? Thats all I need right?

 

The GM IAC and TPS work the same for both throttle bodies, so at the most you might have to change the connectors...not sure since I don't have a TPI style throttle body handy, and my LT1 one probably has a different connector.
Using the Ford one didn't require too much change regarding wiring (we're using the Ford TPS and the original GM style IAC, with an adapter), though the TPS voltage range is different so the closed reading is higher than it should be...it seems to be ok that way, though.
Dale, pics are coming sometime this weekend...it looks like a coated Alien "face hugger"! It seems a lot healthier, but we'll see for sure in about 3 hours.

 

Where would I get differant connectors?? Or could I use the ones off of the V6 TB??

 

Jerriko used the whole tpi center section & welded the v6 runners to it.

http://www.angelfire.com/crazy3/jims...d/34intake.htm

Tiago go this 3.4 intake neck modified to accept the tpi tb.

http://www.force-fed-fabrications.co...P10100264.html

 

What would I use so that my CAI fits onto the twin twin 48??

 

http://www.angelfire.com/crazy3/jims...d/34intake.htm
thats pretty neat , thinksomething liek that would work good on a cammed high compression 2.8 or would it end up being to big

 

The stock throttle body isn't going to hold back the 2.8 under boost. Better to spend money doing high quality exhaust work. If you're absolutely convinced the throttle body is going to be a problem, I'd suggest a custom plenum with a new flange long before throttle body replacement on the stock plenum since most of the 2.8/3.1's intake problems occur at the tight bend in the upper/middle plenum transition.

 

what is the stock throttle body blade diam on a 2.8 and also on a 350 tpi setup

 

doesn't the 1st post that started this board answer your question?

 

no hes said twin 48mm and he isnt even sure if thats right and makes no mention of the 2.8 throttle blade size

 

the answer is in Jerriko's link. I amempowering y'all to learn the answer

 

Well TechSmurf in my first post that started this thread I stated that I am making a new plenum. I wanna know is it worth it to use the twin TB off a TPI setup or should I just use the stock one? I mean under boost I shouldnt have to worry about cfm flow but would it be wiser to run the larger TB so that its less of a bottleneck?

 

the only thing you should worry about maybe is excessive airflow velocities causing lots of drag, which probably wont be an issue as the air is entering the plenum anyway, which(especially on a stock plenum) is the end of the road.

if you're making a new plenum anyway it may be worth it to get a new tb, but remember that when you change to a bigger tb it throws off your idle because each % opening TPS opening is letting it more air than stock. if your tuning with a turbo though, that shouldnt be a problem, so id say whatever floats your boat.

 

hmm thats my fualt i looke dat that page so fast i missed that info on the bottom anyways 2 48mm throttle blades would be way to much opening for the lil 2.8, my idea was going to do something simalar to what he did but not use the uper 2.8 manifold,and just make new runners to connect to the 2.8 ones , or directly to the 2.8 base plate to get rid of that bend were the 2 halfs meet.ill have to think of something else

 

but if your turbo or supercharged wouldnt using a twinblade be better? basicly adding air for a full 2 extra cylinders and then dividing it amongst the 6, which if you look at it like that, really isnt that much more air per cylinder

 

yeah i knew that already the biggest problem is going to be at say with a stock computer/tunning at 15% throttle blade opening it will be letting in X amount much more air. then i t would witht he stock single tb unit. now will the stock computer be able to adjust the fuel mixture to compensate. if not i already came up with an idea to shrink down the 48 mm throttle blades to an apporiate size. im gonna attempt this on a 2.8 na motor high comp and cam headers etc, my biggest thing for doing this is to get rid of the factory runners,mainly the sharp bend were the uper and lowers meet,and 2 for the "wtf" when ppl look under the hood and see the 350tpi upper plenum sitting there

 

this is an awesome intake keep us updated!!

 

the computer will compensate for the airflow at part throttle. the 02 sensor is there for that job.

 

Well I should be getting a call next week about my flange and then after that it should be much more than a couple weeks to finish it. Ill post pics when its done.

 

any of u guys know the volume of the stock runners and length, and if at possible what the stock 2.8 heads flow?? ive looked around and havent been able to find any info, reason i ask cause if i decide to try out that uper tpi plenum/tb i want to take it one further and make all new runners (prolly longer runners for high rpm power)

 

the stock H.O. heads flow like 130 cfm or something

 

i belive it was more like 145 cfm

 

infact here u go
...................Valve lift .100" .200" .300" .400" .500"
no intake-head CFM 64.295 116.9 133.6 146.96 146.96
and with stock manifold
stock intake CFM 55.945 106.88 124.415 131.93 139.445

 

a quick search yields a variety of results from 128 cfm to your 145, so somewhere in there i guess.

 

any ideas on what a set of mild ported heads flow with stock valves

 

any update on the intake?

 

Nothing yet.. The CNC that was gonna be used for my flange broke down. I should get it by middle next week. After that it shouldnt be long till its done..