OK guys If this has come up before please give me a link and I will move along but I have found nothing in my past week of searching. I picked a marine vortec 5.7(volvo penta) with less than 100hrs on it w/ a blown head gasket. When i it bought the guy said it had tbi on it from the dealer.. Well after some research I have come to find that gm used 28psi to feed it instead of the normal 12- 15psi found on most cars and trucks. I have also found that they used a 2" bore tbi unit a set of what i beliove to 4.3 injectors and ran the motor in open loop since it doesnt use an o2 sensor.

Well I would like to put this motor intomy 88 k5 blazer. I know its not a car but I would assume the basic principles are the same.

So far this is the parts list I have come up with.
Ebl flash system.. looks kick ***
46mm bored tbi from xtremefi http://cgi.ebay.com/ebaymotors/46mm-...mZ260147320624
8- 40 psi adjustable fuel regulator
http://cgi.ebay.com/ebaymotors/NEW-G...mZ260147322180
A edlebrock vortec to carb performer intake
A holley carb to tbi spacer w/ 2" bore
arp head stud
felpro head gaskets
Also looking for advice on a wideband o2 sensor


I already have these parts to go on it..
jacobs pro-street ignition with high voltage coil and trigger
New billet distributor
Summit shorty ceramic hears w/o air
New plugs and wires (jegs 8mm)
flexalite dual 15" 5500cfm fans


What im curious is to if this is the right way to go or is there a better way? Also will i need to replace my fuel pump with a high volume version?
Can i delete the egr with the ebl? I would assumse so but im just checking.

Thanx for any help in adavance.

 

As long as you have something other then the stock ECM and the ability to tune, you shouldnt have an issue. I also used similar parts initially on my vortec. Not too bad.

My biggest concern at this point would by why the head gasket blew. Granted it is a boat motor, but theres usually a reason they blow, like overheating, detonating, warped head, etc.

 

Thats what I wanted to hear. Any lessons learned that you might be able to pass down to the next guy?

The reason for the blown head gasket was a pump failure that pumped raw water to the motor for cooling. I plan on a half a dozen acid baths for the block to ensure everythings well cleaned.

 

The edelbrock intake will require some fineagling to get everything hooked up. The cables, hard fuel lines, brackets, and accessories can be a bit difficult to deal with on the aftermarket intakes, depending on how your truck is configured. The other more expensive option is the GMPP vortec TBI intake, which is a stock replacement TBI intake with all stock provisions (except EGR, which requires a take-off from the headers/manifolds).

Also, if you have the heads off, modifying them to accept more lift and upgrading the springs would be a good idea. I wouldnt be surprised if the power was below 300 HP once its in a vehicle with a full street exhaust and all accesories connected and running, so you may want to upgrade teh cam at some point in the future.

 

Question: why would you go with a 46mm throttle body if you already have a 2"? 2" > 46mm. Do the "utlimate" mods to the 2" unit you have, you'll save a ton of money.

 

I think hes referring to the TBI it came with from the factory. I too would go with a 2" TBI if possible, but theyre getting hard to find at the yards and online at a decent price.

 

I had assumed that this project would require some fabrication and thought on the routing and mounting of the throttle cable and the tv cable for the 700r4. The hard fuel line has already been replace with a 3/8" 2500psi marine grade fuel line... It was all we had at work lol .. Does anyone know what the thread and size is for the fitting in the back of the throttle body?

At this point I do have the heads off to go to the machince shop for maganaflux and resurfacing. I may have to look into what it take to modify the heads for bigger springs. If I rember right there only good .450 lift correct? So would just have to clearance the head for a larger valve spring?

A cam may very well be in my future since I have no clue on the specs of the current cam. I would like some thing in the 0-5000 or 1000-6000 range. Volvo doesnt want to seem want to release that kind of information for some reason. It does have 1.6 ratio comp cams roller rockers tho.

I wish I had the 2" unit already but unfortunately all Ive got is a long block and my 1 11/16th tbi from the blazer. I think I may move up to 50mm bore to get as close to 2" as possible. I also considered a 54 mm that flows 740cfm but that seems a lil excessive. Would it hurt any to flow more air? I assume not..

Also is an injector swap goin to be neccessary? I plan to raise the fuel pressure to gain some fuel pressure from the current injectors but would it be a better idea to keep the pressure realtivively tame and go with a higher pressure injector such as 65 lb/ err hr or drop down to the 4.3 injectors(45#hr) and crank the pressure up?

One more thing Ive noticed yall are chaning to high pressure fuel pumps made by walbro. Would this be same unit that is recommened for tpi?

315hp is the gm printed power from it. If i can pull some more out of it while ive got it apart im all ears guy.

Thanx guys I aperciate all the help I can get ...

 

The pumps people have been using from Walbro are the 190/255 LPH EFI pumps. If you use the 255, youll likely need the high pressure pod from GM. These have enlarged passages for increased fuel flow, but are hard to find. Id stick with the 190 if your using the stock regulator. It should be adiquate up to around 20-25 PSI. Although, id still plan on larger injectors. Probably around 65 PPH. This way, you wont have to worry about exeeding the pumps capacity at high pressures or having to run the 255 to at 40 PSI to meet your fuel needs.

 

Sorry, I misunderstood.

 

Ok I had seen those pumps used when I was considering going to a tpi setup. I plan on using the 8-40psi AFPR from extremefi.com and running in the 30 to 32 psi from what I can tell. I used the formulas found on the Budget tbi sticky. Well thats a bit of good news since i already have the 65pph injectors that came with the truck. Is the injector pod upgrade nessecary to run the 255 pump if I already have a AFPR or should I just stick with the 190?

DLV555.. no problem we all over look things once in a while.. thanx for looking

Am I off my rocker to think I can pull 340 to 345 out of this motor with the removal of the stock fan, prostreet ignition, headers, free flow exhaust, the above parts and a performance focused tune?

Can the factory fuel system handle 40psi of fuel pressure consideing it was only designed for 12-15psi?

Has anyone ever heard that the Gmpp vortec to tbi intake doesnt flow very well?

parts list so far:
Ebl Flash
50mm bored and rebuilt tbi from extremefi.com
8-40psi AFPR from extremefi
Injector spacer from extremefi

Parts still needed but unsure on what one
intake
fuel pump 190 or 255?
injector pod

 

As you may be aware that cam in the Vortec Marine is mild. extremely mild. I have a Vortec 5.7L in my boat and I think it revs to 4500 rpms at about 48 MPH. You will get a lot of opinions on cam choice! It however might be an OK choice on an off road 4X4, now that I see it is a K truck rather than an F buddy.

 

That comfirms what I had assumed all along. I figure it would be mild since it has to be to not rock the boat at an idle sitting at dock. I plan to get the motor up and running with the current cam. Then if I still fell the need for an inprovment then I will deffintly do so.

Can anyone confirm or deny the Gmpp vortec to tbi intake to not flow very well? or atleast worse than and edelbrock performer and holley adapter. I have found a used gmpp online for decent price and figure it would make the install go smoother but I really dont want to sacrafice performace for simpilcty.

Also I found a good price on a set of 68# injectors so those will now be added to the project as well.

I figure that I should probally come out to roughly 1250 when its all said and done.. ha and the seller told me it was just bolt up and go lol. I knew better than that.

Heres a pic and a link to the current project

 

how about a dual plane edelbrock performer vortec? with tbi adapter plate?

 

That was inital idea since I have no reason to keep the egr. I only considered the gmpp for simplicity, but I can always fab my own mounts for the tc and throttle cables by modifying the existin mount. Then i would just have to find a way to remote mount the coil and i should be good to go.

 

FWIW, the GM MARINE roller camshaft is the very SAME cam that is used in the HT383 and the RAMJET 350 crate engines. It is small.

This is the pre-Vortec TBI marine engine. They could be had with Swirl Ports, 083s, or 113 Aluminum heads, depending on what was ordered.

http://www.marinepowerusa.com/pdf/57genimarine.pdf

Attached is an Ebay picture of the stock TBI setup used on a Marine 350 Vortec. Notice it is returnless and has a pressure transducer on the typical return fitting.

 

Ok well if it is in fact as small you say it is what a better choice for my application? It will be used a dd everyday, has 38inch tires and 1 ton drievtrain with 4.10's for now, and isnt scarred to be let to WOT in the mud and on the trails where permited? I know for a fact it is obviously fullroller and has 1.6 ratio comp cams steel roller rockers. I know that the heads are only good to about .450 lift before you run into clearance issues. If its a better choice to put in a cam bigger than .450 lift then I will adress the clearance issuses accordingly.. wow a $600 deal on a motor has turn into a complete rebuild of the entire induction, injection and ignition systems. I figure I will be over $2000 by the time its all said and done.. O well its will be sweet when it is done maybe some time in 2010 lol ... till then ill just keep puttin in for overtime.. Thats actually pretty cool how they dont have a return line.

 

If its true that you have the same cam used in the HT383, its not a bad cam for a daily driver. It makes pretty good power, the HT383 makes 340 HP although at a pretty low RPM of 4500. However for a truck this is a pretty good choice, this cam has a very broad torque curve. I'd try this cam out and see if you like it before swapping it without even giving it a shot.

Paul T.

 

I have one brand new if anyone is interested. It came out of my HT383E crate motor and never used.

 

I did this exact swap into my 94 Sonoma 4x4 over the last few weeks. I used a 96 motor with a summit brand 4bbl intake and holley adapter and a 50mm TBI. I used stock 350 TBI pickup injectors (55lb) with an 18 psi regulator spring from tbichips.com. I put in an LT1 cam and roller tip rockers. I figured around 300hp for my project and it seems to be a little short but even 270hp is one helluva lot more than my 4.3's 170! Tuning is still a work in progress so who knows where it can end up power wise...
Here's some things i ran into:
1. vortecs don't have the "extra" hole on the rear port of #7 and 8 cyls so you need vortec-specific headers/manifolds or an adapter plate to bolt on earlier model parts.
2. Vortecs use a lot of parts from earlier SBCs but the timing set, intake manifold, and timing cover are the exceptions
3. Pulleys/accesories from your blazer or any TBI pickup/van bolt on and work just fine. Make sure to use the harmonic balancer that was on the vortec though. It looks huge but the distance it sticks out is the same as the TBI motor's

I guess that's all I can think of at the moment but if you have any questions feel free to PM me

 

Where would I be able to get a high pressure pod from or what's the gm part #? I installed the 255 in my RS with the stock 305 tbi with the expectation of later installing something bigger. I knew that this pump would be way overkill, but only wanted to the swap once. Now the pump is over powering my stock fuel pressure regulator.
Any suggestions?

 

if you keep the large pump in car a thought would be to use an Aeromotive FPR and a larger return line. I am confident it is up to task and will meter the flow accurately. i think it was posted that FP is way too large for a stockish TBI injection system.

 

Vortec350tbigmc: Ive got a few questions for ya if you check back to this..
1. I have been considering the summit intake as well due to the price difference btw it and the edelbrock performer. I have used summit brnad stuff in the past with out a whole lot of issues and it seems to just be alot of rebaged stuff. But everything was only minor no critical stup like plug wires and battery cable kits. Ive never used them for any critical engine parts.. Any issuse with the fit or sealing?
2. Any problem with not running an egr valve?
3. And just to add from my experince.. I finnaly recived my headers from summit yesterday after resturning the last set. They are a set of the ceramic coated shorty summit brand( actually have a flowtech tag tho.. ) for an 87-95 truck w/o AIR, they bolted up just find with out much fusss other than needing to run a tap through the mounting holes on the head to clean em up a bit. All holes were there and lined up fine on my cast iron vortecs...


Studdmst: Im not sure if it would help any due to the flow limitation of the injector pod itself but you could try a AFPR from a vendor. I picked up a 8-40psi unit from extremefi for $50 but have yet to get it it setup so I cant comment much on it. I have also heard the recommendation to go to a larger injector pod found on a 454 unit, though Im not sure if its just a simple swap or if modifications are need for it to work.. I would assume that it just bolts in since the injector bodies are all the same size..

Thnx for the info guys keep it comin..
Ps project is on hold until friday(payday) had to replace the radaitor in the DD .. ouch $350..

 

Good point that pod may cause a restriction. I run a 7.4L TBI so never gave it a thought. any reason why the pod cannot be opened up by drilling the passages? I have had my TBI's apart but cant recall the configueration.

 

Well then your already ahead of the game.. I dont see why not. the casting thickness would be the only major limitation. As well as possibilly being able to essentialy port enough of the pod for it to be worth your while.. I havent seen one taken apart in a while so I can quite remeber either .. Tho I was told that when I suggested I was goin to run at 30psi with 65# injectors, that I would need to run the 7.4 injector pod to support the flow... tho If you ran a set of 80# or 90# injectors at 30psi you might need to start looking at alternative fuel systems as you will have pretty much reached the upper end of the tbi stuff.

Another note you could also modify your FPR that comes from the factory to be used as a AFPR with a lil work and some searching on the boards here, though I belive its max output is 25-28psi..