hey Ferm, need some input

spareparts

spareparts

God
I think we talked about this a while back, but I'm getting close to to ordering parts. If we did, i forgot what was said. My wifes Burb(99, 5.7,1500, 2wd) is showing 212000 on the odometer. I just put a fresh set of LTX's on it, so i gues we are going to keep it for a while. Motor runs great(got 17.5 hwy last week)Figured I'd go ahead and at least have a short block siting there ready to go, I've got a spare 5.7 roller block, rods, and crank(I allready have a set of vortecs waiting to bolt on) in case something takes a crap on the engine. I was going to order pistons, the stock pistons have a shallow dish and a lower installed deck height, I was going to use thin ring standard small block pistons rather than the metric psitons, but couldn't figure exactly which dish I needed to duplicate the stock compresion. I'm going to use felpro head gasket and vortec heads that have had only a little taken off the surface. Block will probably be decked just enought to be square. Second part fo the question is I have a late model complete marine MPI intake setup(Bosch) with injectors, i've heard they are a lot better than the factory MPI intake, I'm not going after all power here, just reliable, fuel efficient, good power that will run off of cheap gas(just trying to be a bit better than stock). I know I'm going to have to adapt the injector harness and will have to do some tuning( I've got a good tuner). haven't made my mind up yet weatehr I'm going back with headers or stock manifolds. Will probably ditch the cats(no inspection in sc) and make a better exhaust. My tuner guy can turn off hte after cat O2s. Once i get the the short block together, I'll pick your brain on a cam and upgardes to the 4l60. My wife drives it daily, I may put it to use pulling a boat or tag-along camper later, but I've got to get it up to snuff first
 
Other than the wiring changes and adapting the EGR valve(or tuning it out), there isn't alot to the marine intake swap. It won't really help your milage any though as the only real reason to do it is to add HP(the stock spider injection is limited to about 385-400HP max due to injector sizing). A set of small diameter 1 1/2" mid length headers WILL help your milage out a noticeable amount though as well as a cam swap. COMP has there tri-power series of hydraulic roller cams and work very well. There milage cam does give you about a 1-3MPG increase with headers, but I thought it was more bark than bite myself and would reccomend there middle series torque cam as it responds very well and is smoother. You will unfortunately have to either go with the special crane or comp beehive springs, or machine the heads to run any sort of lift cam(stock spring set-up will bind at 475 lift). Also you are limited to a single roller timing chain set(the CLOYES is the cheapest and they make them for GM performance) due to the reluctor pick-up on teh crankshaft(you can buy the custom billet cover to run a dual roller cam, but the cover is about $300 by itself then you have to modify your reluctor). As for pistons, I would reccomend a set of the sealed power standard dished pistons for a 87-95 TBI engine. They have almost the same dish to them, and are MUCH cheaper as well as a quality piston(SUMMIT number STL-423NP--(whatever oversize you need)). For a long term engine I would stick with the 5/64 rings for durability. Also FEL-PRO makes a paper replacement intake gasket for these to get rid of the failure prone plastic ones(but the new VICTOR REINZ plastic ones now have steel inserts in them that seem to stop the cracking).

As for the trans, put a BEAST sunshell in it, a TRANSTAR HD torque converter, TRANSTAR basic towing rebuild friction kit, and a TRANSGO HD-2 shift kit, and a SONNAX E 1-2 accumulator housing. They really don't need much as I have torn into them with more miles tahn yours and they still oked good inside.
 
Ferm, i was going to order up a set of those pistons and decided to check compression with the calculator, I'm a bit concerned about the final compression. They list it as a +10cc dish, figuring 58 ccs for my vortecs, 3.48 stroke, 4.030 bore. .037 for the head gasket, .040 for the deck height. I noticed the compression height was 1.540 vs 1.560 on an older piston, so I added the extra .020 to the deck height. I ended up with 9.5-1, a little higher than I was expecting. Give me some input here, were my calculations off or will this motor run at 9.5-1(on regular gas). Thanks
 
Ferm, i was going to order up a set of those pistons and decided to check compression with the calculator, I'm a bit concerned about the final compression. They list it as a +10cc dish, figuring 58 ccs for my vortecs, 3.48 stroke, 4.030 bore. .037 for the head gasket, .040 for the deck height. I noticed the compression height was 1.540 vs 1.560 on an older piston, so I added the extra .020 to the deck height. I ended up with 9.5-1, a little higher than I was expecting. Give me some input here, were my calculations off or will this motor run at 9.5-1(on regular gas). Thanks
 
9.5:1 isn't that much higher than stock for a VORTEC. they came with a shade over 9:1 from the factory I believe as the VORTEC fast burn heads have the small 60 or 64 CC(5.0L were 60, and 5.7L were 64's) combustion chambers from thae factory VS the 78CC's of the older truck heads. I know alot of guys run them up around 10:1, but I believe they run mid grade fuel in them as well.
 
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