this Intake manifold possibile?

[Blazerguy]

Yup.

:sigh:

TPI: lotsa fabbing, can't run OEM AC, larger runners & vortec base needed
SuperRam: lotsa fabbing, can't run OEM AC, vortec base needed...thus very pricey
aftermarket TPI alternatives:
Holley Stealth Ram: lotsa fabbing needed
Edelbrock Pro-Flo XT (7138): little more dough than HSR, lotsa fabbing needed...same stuff as HSR. Looks to accept OEM TB
Edelbrock Super Victor: gobs of fabbing needed, nasty port mismatch, say goodbye to low & midrange power

marine intake is looking pretty good for a minimal pain swap.

[96SLT350]

Marine Intake is the perfect solution. Nobody wants it for some reason.

[paw2000]

The Marine intake has it advantages being able to use a lot of stock components from the truck intake, which saves cost. But it has a few disadvantages also. The weight of the intake is heavy, some intricate fab work. ALso the cost can be pricey for a new unit (leary of a used marine parts, saltwater not good). I decided on the HSR unit. I have had a few issues in the mock up stage but got it worked out. ( http://www.stealthram.com/phpBB3/vie....php?f=5&t=957 ) So far I have been able to use the vortec dizzy with a few rail mod, retain map sensor MAF and evap. Egr will use the divorced setup used on the marine or can be deleted. I have to change out the serpertine belt system to different setup from a camaro as the a/c unit is in the way. So the A/c will be on the passenger side now. Which ever intake is used they all have thier issues. The HSR has good eye appeal, cost not to bad, and been around for a while on the 3rd gen sites.

[19doug90]

Originally Posted by paw2000

I have to change out the serpertine belt system to different setup from a camaro as the a/c unit is in the way. So the A/c will be on the passenger side now.

okay so youre managing to run a third gen pulley setup on a vortec equipped truck? How are you mounting all of the accessory brackets?

That is the only way i could see being able to run a third gen style intake is with the third gen pulley setup but i wouldnt imagine the holes are anywhere near the right spot on a vortec block to hook the brackets up to.

Do tell!!!

[paw2000]

All late model heads have the 3 bolt mounting for accesories, only the early small block motor didn't. http://cgi.ebay.com/ebaymotors/ws/eB...m=110266490299

this link shows the bolt mounting, as our motors use a long mount water pump with reverse rotation (not reverse cooling)so its basically a bolt on option. I'll need to have new a/c hoses made and extend my alternator cable. www.stealthram.com has a good info. Also gmpartdirect list the serpertine belt system with all the bolts, brackets, and even alternator and Ac.

[19doug90]

thats freaking awesome

honestly that just gives me one more excuse to run tpi because i hate the way the a/c is designed on these trucks. Thats good info

[Blazerguy]

Guess I'm gonna hafta go back thru the how to on the marine manifold. I didn't think there was too much precision machining involved. Drilling and tapping a couple of pipe thread holes was the main thing I remember. It's been a while since I read it though. Time for me to do some re-research.

If one was determined to go with a Holley Stealth Ram, TPI, SuperRam, or the Edelbrock Pro-Flo XT (7138) they could buy the bracket kit from GM or go to a salvage yard and get the accessory setup off of a TBI 4.3 (I know 91+) or TBI 5.0/5.7 (I'm thinking 93-95). They are all the same, and will bolt on with no issues. Get a hose set for the V8 TBI truck and you should be pretty close...unless GM hosed ya on a metric accumulator on the newer trucks.

A word of caution though, if you go salvage yard hunting for all the goodies don't forget to bring a power steering pump pulley puller with you or you will never get the bracket off the head.

I'm curious to see how the Edelbrock Pro-Flo XT (7138) stacks up to the HSR. One difference is the Edelbrock unit uses the LS1/L31 style throttle body as opposed to the old twin butterfly of the TPI era. Plus it looks to be more of a as-cast version as opposed to the HSR...which looks best when polished but that doesn't fit with the underhood look of these (well...at least mine) trucks.

[paw2000]

All the different manifolds will work with enough effort applied. I just couldn't see bolting 75lbs on the top of the motor, and with all that mass the additional heat. On a boat thats using raw water cooling, 70 degree water is being circulated and water cooling is much more effective than air to water we use in radiators. There is also a lot more options for throttle bodies for the HSR, and like most hot rodders we all like the glimmer of new,different performance goodies. I was also understanding that boats run a consistent throttle position, usually 3000 rpm after its up on plane. A boat doesn't coast. let off the throttle and is slows down quickly. So a manifold for a boat might be optimized for a particule rpm range and prop size.

[Blazerguy]

Eh, boat throttle position varies quite a bit depending on your speed and water conditions. You might be putting along slowly at a very small throttle opening at low rpms. You might be cruising slowly at part throttle anywhere between 2000 and 4000 at a multitude of throttle openings. You might be at 5000 rpm at WOT doing a full boogie across the water. Depends on the boat, engine, gearing(trans or lower unit), and prop as to what rpm is top speed. The higher the throttle opening, the more rpm and the more load the engine is under. Pretty much any time that throttle is wide open is 100% load.

Boats see a lot more transient rpms, loads, and throttle openings than people think. You are right in that there is no coast mode with its fuel cutoff but that is totally in the computer not the manifold. An argument might be made for injector angle affecting idle quality and cold start characteristics but that could all be tuned to the point of a nonissue.

With the HSR and its oval throttle body, ya gots to plan for the oval inlet tube of the TPI setups, keep that in mind. As to more throttle body options for the HSR...I dunno about that. The Edelbrock unit uses the LS1 style throttle body...and there are myriad options out there for those throttle bodies. Not sure that the large dia tube for the LS1 style throttle body would be any easier to fab an air inlet but it is certainly a bit different.

Not starting a peeing contest, just discussing.

[Pauly]

The marine and L31 intakes are VERY similar on the inside. If it works well in a boat, it will work well in a truck. Its obvious the L31 and the marine crossram intakes BOTH share identical design elements


We are starting to see some Vortec engines dynoing 340 rwhp and 390 rwtq using Vortec heads that are natuarally aspirated.

Its nice to be able to properly fuel an L31, and still have lots of injector left for a turbo, supercharger or dty nitrous hit.

The marine intake is a GM designed peice. NONE of the other intakes are. The purpose of the marine intake was to have an intake that looked stock, could fuel big power and fit the stock throttle cabls, and air intakes/superchargers that were designed for the L30/L31. The marine intake looks stock and has more of a chance on passsing a visual emisssions test. Try that with ANY other intake.

I drive a truck, I can afford an extra 30 lbs. for the possibility of running 500 rwhp with a turbo/blower or dry NOS. With the stock L31 intake, 350rwhp from a blower was a lot/ HAving actual fuel injectors that are actually serviceable in a larger flow rating was the main goal on the marine intake. Teh marine intake swap and the 411 PCM swap are 2 major reverse technologies that are now allowing BIG power to be had and more easily tuned on the 1996-2002 Vortec L31 engines.

Any intake that houses larger fuel injectors can be made to work, and work well on the L31 engines.

peace
Pauly

[19doug90]

just curious how much do the whipple s/c run for the stock style intake?

I'm still leaning heavily towards a tpi swap (got a serpentine setup on the way) but prochargers arent exactly cheap

[Blazerguy]

ProCharger may not be cheap but boy do they give you a lot of bang for the bucks. I'm totally not a fan of the particular FMU they use on these newer higher psi fuel systems. They do have some that work better....then again the best way to fuel them is with a boost aware pcm like the 411(patched of course)

[19doug90]

Originally Posted by Blazerguy

ProCharger may not be cheap but boy do they give you a lot of bang for the bucks. I'm totally not a fan of the particular FMU they use on these newer higher psi fuel systems. They do have some that work better....then again the best way to fuel them is with a boost aware pcm like the 411(patched of course)

feel free to elaborate on that

i dont know much about s/c's nor do i know what you mean by a "patched" 411

[Pauly]

I beleive he means runing a 411 PCM with a custom operating system "patched" into it to allow the 411 PCM to read a 2 or 3 BAR MAP sensor. The stock 411 will only read a 1 BAR MAP sensor.

A higher stall TC is key to a centriguals performance. They dont make good low rpm torque, but make excellent mid/upper rpm power and torque.

peace
PAuly

[Blazerguy]

Lol, sorry, that is what I meant. 411 PCM w/ operating system patch.

Good call on the torque converter. A centrifugal will give you a boost down low, but not like it does in the mid to high end.

Most people aren't quite prepared for the difference a good dose of intercooled boost makes.

I'm a good bit torn. I like the notion of what I see to be less fabrication with the marine intake...but I've always liked the look of the TPI manifolds. Guess in a way it's a good thing I have a few months to decide.

What have ppl ran into trying to use the L31 distributor with the TPI intake? What about the HSR? I seem to recall something about that but can't place it at the moment.