Thread: 300hp fuel injected sbc for under a grand? Is it possible?

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Here is what I have already,
1990 suburban, all stock, 2wd, TBI350 motor runs fine other than smoke from valve seal
set of long tube headers (not installed)
cheapo thrush (2)mufflers with 2.5" piping all the way back (not installed)
Throttle body spacer (not installed)
new shiny air cleaner (just put on today, no noticeable gain but sounds good)
a set of camel hump heads with the 1.94 valves (not installed)

I want more get up and go out of suburban, 300hp is the goal. I did Not plan on pulling the motor out or touching the bottom end at all. Now here is the tricky part, I want to keep the TBI for reliability reasons and I love having my remote start http://www.clubhotrod.com/images/icons/icon12.png

My plans are to Install all parts listed above along with:
electric fans
no cat converters
maybe bypass EGR or do some emissions modifying? (info needed on this subject)
gasket match port the heads and intake
All new gaskets of course

And I am debating on the holly throttle body unit that comes with the bigger injectors? and/or some MILD cam options. As I said before I want to keep it fuel injected and have no tuning experience or access to a dyno. I hope to be able to just get it close enough and run 93 octane always.

Does this sound doable? Is there anything I should add to my list or take off of it? What do I do for the fuel side of it? bigger injectors? FPR? Is this doable for under a grand? What are peoples opinions of the holley throttle body?

I know a few guys who have gotten excellent results on similar engines but they used the Vortec heads instead of the old camelbacks. As for the cam, you might want to go to the Comp Cams website and download the Cam Quest software (freebie), it will suggest some cams that will work great with the TBI..or a phone call to their tech department will get excellent results, too. Sounds doable to me, other then the heads. The Vortec's will make some very nice power in a usable RPM range for your 'Burb.

Your TBI won't support much more than 300 HP. you'll need the Holley/ 454 TBI.. I would suggest the Vortechs also. you will nee the vortech- TBI intake or the Vortech 4bbl intake and a 454 4bbl- TBI adapter.. Your not going to break more than 250hp with the swirl ports.

1990 engines had accessory brackets in the heads......the typical "double hump" heads did not have
the holes and you cannot drill them.

you will have no trouble getting 300 horsepower with those double hump heads. factory 327 with those old style heads was getting 375 horsepower with the old fashioned mechanical fuel injection in 1964. you will have slightly smaller valves and less compression but more cubic inches so well over 300 horsepower is doable.

Hi,
I've got some experience with successful TBI HP mods, I'm on my second modded vehicle. I've heard good things on Vortec heads but haven't used them yet, I'm putting a set on a marine mill now. I'm running 180 cc runner RHS heads on a 9:1 383 stroker with really good results. I used the 68 #/hr "cop car" injectors and a TPI fuel pump, i modified the fuel pressure regulator to make it adjustable currently the pressure is 20psi. The manifold is the Holley projection 2" bore one, I've heard really bad things about the Holley tbi unit, and I had a 350 one bored out to 1.930" from my last vehicle 1990 full size Blazer and it works great. I had to hog out the center 4 bolt holes in the manifold to use the early bolt pattern on my heads. The cam is a hydraulic roller from Comp Cams with 210/218 duration at .050" lift and if I remember right a 113 degree lobe separation, lift with 1.5 roller rockers is around .5", (comp cams actually recommends 1.6s with that cam). I ran Stans headers into a high flow cat and 3" single exhaust. I retained EGR buy plumbing 1/2 copper with a heat shield on it, from the EGR fitting in the headers into a compression fitting just below the egr valve in the intake manifold, (no heat passage provision on the heads). most importantly i had a chip burned by Brian at Harris Performance "TBIchips.com" which optimized the package. the vehicle is a 1992 full size Blazer 4X4. The problem is I've built something I'm afraid to open up, my nerves give out at about 4000 RPM in second gear. That cam has a flat torque curve and shows no sign of running out of power shifting at 5,000 RPM. I would like a little more power below 1,500 RPM, it really kicks in as it approachs 2,000 RPM. I'm running it strait up. Excelent for towing and I'd like to get it to Englishtown just to see what she'd do, probably mid to low 14s. It does lack that peak power feeling that a cam 2 sizes bigger would give in the higher RPMs.

375 hp from the f.i. 327 was measured the old way. By today's standards of hp measurement, those engines were probably not putting out more than 350 hp. Not bad, but that was using 45 year-old technology.

well hell, you guys are right, The camel hump heads do not have the accesory holes drilled in them for the brackets. So there goes that idea. Would it be beneficial to rebuild and slightly port out my stock heads? could I get some with bigger valves/more flow? I have heard of people using 305 heads on a 350 block. What should I be looking for? I dont want to do the vortec's because they are expensive, and I dont want to have to buy a new intake. I think that will put me well over a grand.

Not to be rude Bud.Thing it is when you need parts that cost more than you planned for,well it's time to expand your budget.Save more taking the time to get together the funds.

Once you port a swirl port head, you eliminate any decent torque curve they had and create a useless hunk of cast iron.. there 50% useless as it is. there out of steam at 4,500 but there torque curve at 1,500-2,500 RPM is great... Your in Ohio. useable Vortechs go for about $125 each gaurenteed at a junkyard. you could use Car-Part.com--Used Auto Parts Market to find a pair. You'd have about $600 into the swap. tune it and you'd have close to your 300hp.