this will be my first lower end rebuild but it dosent look to be much harder than a topend rebuild so i have just a few(?). so what i would like to know is i have a short block 350 assembly i picked up for $30 from a 1990 chevy pickup that had slight rod knock one morning so was shut down and replaced asap.this was a tbi motor and when running dynoed at 200hp and 310tq at the rear wheels with 9.3.1 compression. would this be a good starting point to build a nice mild tpi or lt1 with? pistons and crank in good use able shape cam and flat tap lifters have to go. could i put a set of roller lifter in a block that had flat tap lifters? i'll post up some pics of pistons and crank for a second opinion on whether they look good or not along with a few of the block and how she looks so far. would the oil pan that came on motor from the pickup fit im my 85 camaro or would i need a diffrent one? i'll more than likely have a few more ? but ill think of them when its not 3:00 am. for reading and any help in advanced guys

 

took some picture's today let me know what you guys think.pistons seem to be in great shape just need cleaned.what could i clean them with?here's what they look like.

 

here's a few of the crank does it look useable to you guys?looks good to me might just need polished or turned.

 

that crank will definitely need polishing and i would not use those pistons being if you are doing a budget rebuild i would use a set of claimers maybe from kb pistons or something , a stock rear sump chevy pan will work just fine in your 3rd gen and why do you want to go roller on a stock rebuild however get the crank checked .....birdman

 

Not that block. It hasn't been machined for the factory type roller lifters. Retrofit lifters would be very expensive - very poor HP/$'s investment.

If it had a knock, did you find the source? It has to be either crank bearings or piston wrist pin.

That engine doesn't look like it was well cared for at all. I suggest you assume it needs a complete rebuild, including all bearings, cylinders rebored (which means new pistons and rings), and the crankshaft at least polished if not turned (a competent machine shop can advise on that).

 

Did you spin the pistons in the bore? Some are pointed in the correct direction, others are not.

 

well first off let my say thanks for the responses and that the piston pins on cylinders 3,6 were in really bad shape and is what i suspect the knocking was from.i have no intentions of keeping this at stock standereds wanting to build a nice mild but tame motor.i would be more than happy if i could get this 250-300 hp out of this motor nothing to extreme.now ive been reading several other forums on here and now im not sure on what direction to build in,tpi is rpm limited,lt1 setup wont fit on my block without work thats out of my area of expertise and price range.im not to great with carb's either,tbi is simple but has limits to what you can do to them.so im a little lost on what would be a good compatible build for the block i have.im in no rush to build this as its on an extremly tight budget and the carb'ed 305 in my car only has 25,000 on rebuild so atleast i can still drive my baby for a few years.just wanting to upgrade in the near future with a motor that i can finaly say i fully built from the ground up with.i dont know about you guys but there's nothing better to me than the feeling of sure acomplishment from hearing your ride fire-up and drive off after you tear it apart and put it back together.well maybe beer and sex

 

yes five7kid i set the pistons back in original bores just to take pics of how they looked,sorry should have mentioned that before.so i cant have roller lifters no big deal ive always had flat tap's.now im just trying to throw around a couple build ideas but ive been looking at the SFI sytem thats on the 96up vortex chevy trucks and my question is will vortex heads go right on this motor or will they need machine work to fit?if i build this with a tpi set up i could run a set of flat tap lifter with it right?sorry if some questions seem dumb im just trying to see my options on building my first motor.thanks guys

 

Vortec heads will bolt right on, the kicker is the intake bolt pattern and port height differences

 

Bad piston wrist pins. Not too surprising. Make sure it isn't the rods causing the problem.

I've never heard glowing reports about the Vortec SFI. Go ahead and use the heads, but plan on either a 3rd gen EFI or carb for it.

 

i really want to build this with EFI of some kind,since gramp's passed i dont have anyone that knows hows to properly tune a carb and the local mechanics dont know their *** from their elbow.now this might sound stupid but how do i read the specs for a camshaft?im getting confused as to what duration and lift should be ive put them in just never had to pick one out myself.what makes the tpi system rpm limited?could a cam and lifter set change this?local machine shop said block should clean up real nice with a .10 overbore but i havent seen to many engine kits for .10 over applications.should i punch it out more say .30 over or do they have smaller kits i havent looked at yet?thanks for all the help so far guys

 

TPI stands for Tuned Port Injection. The inlet tract is "tuned" for lower RPM operation. This was to give good seat-of-the-pants performance and good fuel economy. This tuning limits power above about 4500 RPMs, so if you put in a cam with a higher powerband, you'll lose the low end and not gain anything at the top end. The only choice is to change the TPI hardware with aftermarket stuff.

The Holley/Weiand Stealth Ram is a good choice to overcome those limitations. If you find a complete TPI system with the harness, sensors, etc., you can install all that on the Stealth Ram.

The cam should be "computer compatible" to limit tuning challenges. People seem to be making good EFI power with the Comp XFI series of cams.

Be sure you properly prep whatever heads you end up using to work with the cam you choose.

 

No offense but for the type of questions you are asking you need to get an engine rebuild book and go through it. If you are asking how to read camshaft specs you shouldn't be putting an engine together. Everyone has to start somewhere. Assembling a short block the right way is more than just slapping some parts in a block. Use the search function on here for other peoples builds.

Learning to tune a carb isn't that tough. It's cheaper and some may say easier than using EFI.

Best of luck to you and please don't think I am trying to talk down to you because that is not the case. I don't want you to throw money away not knowing what you are doing yet.

Jason

 

Only good advise I can give you is this, make sure you come up with a plan of what you want like street, street/strip, road race or drag race etc etc. Your budget will play into what you are able to go for. Your lucky to be starting with such a wonderful engine as your first rebuild, the small block chevy is in my opinion the best engine to start on.

Now if your building a street engine your DESIRED power band will be lower so a TPI system would be preferable.

Street/Strip would involve more RPM so at least an upgraded TPI or HSR like what you were looking at would be your best choice.

Drag Race brings you into the sphere of the high end objects like maybe a MPFI system from one of the big name guys, and again more RPM.

Now something to keep in mind is that an engine doubles its load on the rotating assembly from 5500 to 6500 rpm, so like I said your budget will determine alot.

Hope that helps point you in the right direction.

 

thanks for the responses and im not easy to offend so no harm done Liljayv10.i only asked because i was'nt sure what lift/duration i would need for my desired hp/rpm power range but i think i got it figured out.now here my build list plans so far so what do you guys think look descent.

weiand vortex stealth ram power from idle to 6500 rpms
edelbrock performer rpm cam and lifter kit duration 308 int/318 exh lift .0488 int/.0510 exh rpm range 1500-6500
edelbrock sure seat valve spring kit and pushrod kit that match cam's specs
accel 24lb hr injector kit
tpi fuel rails,and dist
summit racing (quite) gear drive
thats what ive got picked out so far still waiting for final results for what block needs rebuild wise its a machine shop now.will my stock crank withstand this kind of torment or should i buy an updated crank?just so you guys know what im looking to working with is $1800-$2500 or so but this will be over a 2-3 year spand.thanks guys

 

you will need to get a good balance job done on the stock crank to make it live at 6500, but otherwise you should be fine. just keep in mind that it will come apart if you over spin it and at $169 you could have a better crankshaft.

http://www.summitracing.com/parts/ESP-103523480/

I would recommend it, I have a 400 small block that I built on the stock crank and I really do regret it. I lost a heck of a lot of potential for power really quick.

 

i have a few more dumb question but how do you measure piston rods to determine lenght?dont i measure center to center like when measuring for a lug nut patterns?if i use a crank thats 3.75 in stroke compared to my 3.48 in stock stroke id have to use shorter rods and pistons right?f-body demon i was looking at that same crank a few days ago so i think im on the right track.thanks again guys

 

so ive been shoping around and cant decide on which pistons to get ive narrowed it down to 2 sets which would you guys pick?
http://www.summitracing.com/parts/SUM-17350-30/ or
http://www.summitracing.com/parts/UEM-9901HC-030/

here's the rest of build list.
weiand vortec stealth ram
edelbrock rpm performer cam and lifter kit dur.308/318 lift 488/510 power band 1500-6500 rpm
edelbrock sure seat valve spring kit matches cam's specs
summit racing push rods match cam's specs
scat cast steel crankshaft 3.480 stroke
5.700 in eagle SIR I-beam 5140 steel connecting rods
accel 24lb fuel injectors
summit racing quite gear drive
thats what ive got so far any thing you guys see that i might need to change or upgrade?thank you to all who have replied

 

I would say the KBs. The summit pistons are just basic stuff and with that im not very sure how they would handle 6500 rpm. BUT I dont have any personal experience with them so if someone else has they should chime in for sure.

But remember both of those wont handle nitrous or boost very well, but the KBs will be marginally better if you decide to use them. Nitrous in particular WILL burn a nice big hole in those pistons if you overheat them.

 

no plans for nos or boost.planing on a nice naturaly aspirated build basicly a strong tuff street car,might hit track once or twice just to see what she runs.the kb's where my #1 choice,has anyone used the bbk power-plus series 58mm throttle body?how did it work with your setup?would this fuel pump provide enough fuel or is it to high of psi?http://www.summitracing.com/parts/SUM-G3138/
thanks again guys

 

To do the builds you seem to be interested in, you're going to have to read some good info. Amazon is a good place to get DAvid Vizard books and a rebuilding the small block chevy book. Redone recently with 600 pics!

Info on the forums is great, but you need the info and confidence from your own learning.

Thirdgen seems to be the best site for FI tuning TPI. Maybe even the newer FI GM as well.

Carbs are a very complicated and complex device. It is only from the dedication of the engineers that they perform so well even with a backyard rebuild and tune. I know someone may pipe up and disagree, but I would say that FI is easier to tune and understand, once you put the effort in.
Carbs are complex because of the many dynamic pieces and tolerances that can all be tuned or modified. Easy to achieve an 85% solution, but now with wide band O2 sensors, carb tuning has gone to a higher level. From accelerator pump shots to idle air bleeds to power valves.

 

A few errors here. First, the LO5 was 210 hp and 300 ft-lbs at the crankshaft, in 1990. Second, it was 9.1:1. Third, being a short-block, the rating means nothing if you use better heads. They really mean nothing even if all you do is a better muffler.

 

I would like to assume that you would use a roller cam. But just in case I definitely discourage using a flat tappet cam with roller lifters. You'd have absolutely no duration. I know this has already been covered, but for future reference.

 

For the kind of horsepower levels that you're interested in (250-300), I would suggest that you stick with TPI. Keep your life simple. TPI makes excellent torque, and in the modest horsepower range that you're looking for, you don't need or want a lot of RPM. A motor that makes 300 horsepower at 6k rpm is going to be a dog on the street, where a 300 horsepower TPI 350 will feel like a rocket ship in comparision. Hell, my 91 TPI Corvette, while significantly slower than my friend's 2010 Grand Sport Corvette, feels faster from stoplight to stoplight because of the huge low end torque.

I can't emphasize enough how much fun low end torque is. If it was me doing the build, I'd put my money into the right heads and induction. For your horsepower levels, cast pistons with a reconditioned stock rods & crank are all you need. That leaves money for a decent set of small port heads (170 or 180cc heads) and a nice TPI setup, maybe with aftermarket base & runners if it's in your budget. Pick the right cam and this combo should get you into the 12s without breaking the bank, and without getting into anything exotic.

To keep it even more budget oriented, forget about the EFI and slap a carb on it. It's a carb... every old guy in your town can probably tune it for you, and if not, there are a thousand books out there that'll give you the education you need to do it yourself.