I have a chevy 1993 2500 with 350 TBI I was wanting to know a few cheap things i can do to get more power out of it so far I have flowmaster K&N and comeing soon headers

Thanks

 

Ignition is always a good place to start. MSD coil and 6A, and 8.5mm or 8.8mm wires worked great for me.
Ultimate TBI mods are popular as well.

 

I have changed the stock wires to some HP ones but i havent to the coil..

 

How would you wire an MSD coil and a 6a to the Ignition?
Isn't it controlled by the ECM to the ignition module?

 

ignition is a waste of time for street level performance, any good tune up will give you the same gain from stock components without spending a bunch of money. new plugs, wires, and cap and rotor will do just fine.
if you wanna get a big gain at a low price, follow the ultimate tbi mods and open elemetn with a little mroe gear. look aroudn on some of the web sites to find out what gear ratios were available in your truck in different option packages. most likely if you find a 4wheels drive model or soem kind of towing package model you can find yourself soem 3.73's or 4.10's and many models prolly came with posi's too, the code for that is G80 in almost all gm models.
look aroudn for a used performer tbi intake next. you can usually pick them up used for about $125, add a few gaskets adn you will have a noticable gain for under $150.
a full exhaust is also useful. in an effort to keep vehicles quite gm undersizes their exhaust and usually just takes teh cheapie route when it comes to a y-pipe. your local muffler shop can make you a y-pipe on teh cheap prolly and after market cat badk systems are everywhere.

later
tim

 

DO THE tbi TRUCK BLOCKS have ROLLER CAMs and lifters???
what about the caprices????

 

most of the trucks are reguar hydraulic lifters. caprices should be roller motors though..

later
tim

 

My '93 Silverado has a roller cam block, but trucks got a hydraulic cam/lifters from the factory. The block is drilled for the spider roller-lifter retainer, though.
SC

 

IMS, Chevy passenger v8 cars got roller hydraulic lifters in 1988.... including the Caprice. The trucks stayed with non-roller hydraulic lifters to the end of 1995; in 1996 they got roller lifters, starting with the L31 engine (which replaced the truck LO5).

And yes, the non-roller truck engines from 1988-1995 were cast with provisions for the spider that retains the rollers. So 1988-1995 trucks owners could add roller lifters by adding the lifters, a roller cam, and the retention spider.

FWIW.

 

The trucks suffer from the same problems the cars do.

1. Crappy heads

2. Worthless cam

3. poor designed intake

4. cheap restrictive exhaust.

That is where the money needs to go. Ignition related parts on a stock/nearly stock engine is not a good bang for your buck. Concentrate on the above and you won't go wrong. You may wish to attack that list in reverse order though.

Also, the LT1 cam the car guys use works great in the trucks too. When I did my truck, I got the lifters, spider retainers, and cam from a 95 Z28 off ebay for a $100 and it was a great investment.

 

So let me get this straight, the lo5 truck motors can swap a roller cam in with by just adding the spider, lifters, pushrods and cam from the roller motor? I have an 89 lo5 truck motor and have been following this and havent found a steady answer to this. I am looking for a direct swap with the motor still in the truck. Tapping the spider bolt holes wouldnt be a problem but is there anything that i am missing? Someone please clear this up for me. I am thinking on going with a roller cam and the vortec head swap for the final set up. Nothing fast just a little more power when i need to swap the heads do to a bad valve guide that is smoking on start up at the moment. Thanks guys.

 

My Dad has a 95 suburban and it's so freaken slow. The rev limiter built into the eprom is 4800rpm and when it hits that revlimiter resume of fuel doesn't start until 4100!!!!!
So for Christmas I got him an open element and an Lt1 cam, total investment so far is $15 (lt1 cam was free). I'm going to replace the valve springs for what ever they cost, then I'm using my old Lo3's roller lifters. I hope he fronts the money for some headers. When it's all done and installed I'll datalog and burn him a new eprom. I'm looking for some decent gains but I'll have to make sure the fuel pressure checks out okay. If it doesn't and the injectors get too close to 100% duty cycle I'll have to make the stock FPR adjustable. I've got a few sitting around here I could probably do. Anyways, I think this is a very good start don't you agree?

 

Thanks for the replys, How hard is it to install a cam? like what all must come off?

Also I took care of the exhaust just cut it off befor the cat that was ahuge gain.


Thanks

 

I believe gm tapped the holes beginning in 90 so you will have to tap the holes. The LT1 cam makes a nice truck cam by not sacrificing too much low end power and really opens up the top end. You will need the spider, lifters, pushrods and cam from the roller motor. You will also need the timing chain for the roller cam since it has a different bolt pattern than flat tappet. I recommend the GM timing chain below since it comes with both types of roller cam retainers that GM used.

GMPP P/N 12371043 = timing chain/gears and roller cam retaining plate kit (1st and 2nd design plates!)

 

Thanks for the responce. This pages is now in my saved catagory for future reference. First things first got to get the new wiring harness in the firebird.

 

I know this thread is old and out of date but I want to say something that was never mentioned and it is important. It is a common misconception that all LO5's are roller ready blocks with flat tappet cams and in a lot of cases that is wrong. I know that my 92, a friends 90 another 91 and a 93 pickup along with endless junkyard LO5's are not roller blocks. You have to have a cam thrust plate and most important the 3 1/2" tall bosses in the lifter valley and none of the above engines mentioned had those. The known trucks including mine are all original and are running the original engines. There are a lot of people who figure you can swipe a truck LO5 and throw the roller stuff in and this stands true for a lot but there are also a lot of other LO5's like mine that cannot use a roller cam at all unless you want to run aftermarket roller lifters. This is just a tidbit I thought noteworthy, yes you will find many roller LO5 blocks but not all are, in fact I have seen lots of them opened up and not one was roller provisioned. There have been endless debates over this but my truck is living proof, not all LO5's can run roller.