Help with creating "the plan"

[rrubel]

Now that I've done about all the simple 'freebie' mods I can do to my car, I'm taking the advice of 'listers and creating a master plan for bigger improvements. However, where to start? What to do? I'd love to hear suggestions from people who've been there/done that regarding the following scenario. I'll try to map things out as specifically as possible.

1. While I'm not afraid to work on the car, I haven't ever done anything to major engine internals (ie, never taken off the heads or replaced a cam or anything). I have all basic tools and some not-so-basic ones, and will buy or borrow anything reasonable. I can (usually) follow complex instructions and I'm not afraid to ask an expert for help or advice if needed.

2. Assume my budget is about $3-3.5k spread over the next three years. This is essentially worst-case; I hope to have more sooner but must work within this amount.

3. The car *must* remain streetable - not as a daily driver, but more than an occasional. Exhaust mods must be wife-tolerable while cruising.

4. The car: high-mileage 86 L98 coupe with 4+3. Non-stock exhaust, but no clue what it is. Done roller rockers, AFPR, all possible mods in front of the TB, 17" wheels, cooling changes (tstat, manual boost fan, lower-temp main fan), centerforce DF clutch. Assume suspension needs no mods. Assume nothing major is going to break and need repair before the three years (yeah, right ).

5. The goal: 13.3-13.5 at the strip, auto-crossable, streetable, minimal loss to low-end torque if possible. Try not to lose too much fuel economy while doing normal cruising (so 4.09 gearing is OUT). I do want brake upgrades as well.

Any takers? Consider this a challenge... Or at least a good debate topic.

Gentlemen, start your engines...

Thanks much!
[RICHR]

 

[Edmond]

I Love Threads Like This!!!!

Can anyone give me a hell yeah for the mini-ram???:L and how about the Vortex Rammer Air intake?

 

[Mad-Mic]

heya Rich lets get together soon i'd like to see what you've done so far! i'd like to see your rims

 

[Vettelt193]

How high is high miles?

A supercharger would fit perfectly into your project... you won't have to dig in to the engine, not overly costly (depending on which one you get) easy to tune, low-end torque remains, more high end HP, no need for gears, and you keep your gas mileage... L98's run really good with only minimal boost... say 4.5 psi... you won't feel the car running out of breath anymore...

 

[rrubel]

High miles is 135000. I've replaced normal wear items (water pump, alt, clutch stuff) but nothing inside the engine other than pushrods and rocker arms. How well would a supercharger fit under a stock hood and what would need to be beefed up to prevent internal meltdown? I'm familiar with forced-injection on Subaru's but not really on SBC's.
[RICHR]

 

[Vettelt193]

Well... here is the deal... with 135k, you MAY have problems with whatever you do, unless you rebuild... If I were to supercharge your engine, I would stick with low boost... 5 psi Max....

There are many superchargers out there... A basic feel of the market is ATI procharger is the best, Vortech second, then the others falling behind... ATI would be intercooled, much better on your engine, but very costly... figure 6 grand for ATI (but with ati, you can run more boost because of the intercooler)... a more price friendly supercharger would be something like powerdyne (I know they make an F-Body charger, but not sure about Vette) these are much more in-expensive (fits into your price range)... they aren't built to withstand a ton of boost, but in your application would be fine. Any supercharger you pick will fit under the hood... a powerdyne won't even make noise, so your vette could be a bit of a sleeper if you wanted it to.

As far as installation, you may have to move around an accessory or two, but if you get one built for your car, there should be no problems.

 

[warren s]

Rich

In my experiance a fresh engine would facilitate more power in conjunction with some cylender head work, a new cam and a good exhaust. The existing intake would be plenty.

As your power plant is really not that far from being in the mid 13s to begin with. Maybe some higher compression pistons.

Any forced induction on a extreem milage engine may prove detremental. For an investment of 3.5K you should be able to do a cam, have the heads done and a stock or mild rebuild if you remeove and reinstall the engine yourself.


I had a 210Hp 87 Firebird Fourmula , the first year with the 350 and after 90k, I had a stock rebuild, bottom end wise and some light porting on the heads, a new cam and roller lifters, a SLP exhaust and with a 3.23 rear the car was in the mid 13s.

 

[Vettelt193]

The problem with heads, a cam, etc. is they all raise HP, and peak HP rpm, so low end torque will be sacrificed.... And unless the engine is rebuilt, there is no stress difference between a mild blower and a cam and heads... what it comes down to is the power the engine can handle... it is always a tough call to spend your money on rebuilding/internal Vs. external mods.

 

[BigRed]

My opinion is do the bottom end. Take the block to a machine shop to convert to a 383 Stroker. That will give you lots of new ponys to play with but also if you ever decide to add more things to it like a Supercharger or Miniram you won't have to worry about hurting your motor. Here in Canadain dollars its 6500 (So 3900 US) and that includes some Edelbrock performer heads, Crane cam, And Lunati guts.

Oh ya and they build it for that price as well.

(Prices quotes from)

Pro Stock Performance
Campbell Engine house

Both in Edmonton

 

[warren s]

The problem with heads, a cam, etc. is they all raise HP, and peak HP rpm, so low end torque will be sacrificed.... And unless the engine is rebuilt, there is no stress difference between a mild blower and a cam and heads... what it comes down to is the power the engine can handle... it is always a tough call to spend your money on rebuilding/internal Vs. external mods.

How could there be no stress differance between forced induction and just more efficiant induction?

Also, the cam choices for a chevy small block are so varied that you can increase power accross the entire power band with out losing the bottem end, the overall power increase however would result in a quicker car. In my experiance there is no question in this case, at 135,000 miles, you should rebuild because most likly the owner will be testing the new mods at length and the bottom end will be the first to go.

A possible exception would be if the car had synth oil changes every 3k and was really not driven hard, even at extreem milage it may still be fresh and not losing any compression at higher revs, somthing a compression test does not always show.

 

[Edmond]

At 135K, it wouldn't be a bad idea to rebuild the engine. That would ensure safety and reliability when powerful modifications are done. It's kind of like stretching before you lift weights.

 

[rrubel]

At the risk of sounding stupid, what would be involved in a "rebuild"? Valves, springs, gaskets, bearings? More?

Is this shadetree-doable?

One of the reasons I'm soliciting suggestions is because I won't have the whole wad of cash at once so I was hoping there were things I could buy and add or save up to add later as I went along. Among other things, I spend a lot of time on eBay and could watch for cams and such for months until I find a good deal.
[RICHR]

 

[Eagle85C4]

Well Sir....you should look at www.paceparts.com
You can get a brand new 350injected motor for 1400.00, last time I looked the same motor came out in the Caprice with TBI.
Add a Crane Cam #2040, throw on the TPI made for the vortech heads. And there you have a stout little motor...brand new with warranty for under 2000.00, with plenty of room to build on if you so desire...but you are looking at close to 330 hp...which should be enough for anyone to play with...Just my .02¢

 

[warren s]

Rich

Usually you just remove the engine, remove the heads and accessories and bring in the short block to be re-built. The heads are a separate deal and could be redone anytime.

A good short block rebuild, would be-

Hot tank the block, and magnaflux to check for cracks
line-hone the main bearing surfaces and cam bearing surfaces
Check deck surfaces
magnaflux the connecting rods and pistons
replace all piston rings
check the crankshaft
possibly over-boar the block
replace all bearings and freeze out plugs.

There may be a few more items hear and there, it been some time since i did one. Remember you have the most options in every aspect of the rebuild and the most availabilty of shops that can do this when you have a 350 Chevy engine.

 

[BigRed]

How mechanicly inclined are you?

If your not very, do you have a buddy who is?

Rebuilding a engine to run decent isn't true rocket science. Buy a GM build book for your car as well as some "ups" books from your local Performance store. They will show you step by step basicly.

Warrens describing a basic good to go rebuild.

If your doing some performance modifications do exactly what he said, but start replacing some parts. Buy some pre built heads (Edelbrock I like because of the durability, performance, and value) Talk to some guys who know your engine about bigger cams, change the pushrods (They're cheap and why throw old ones in)

A couple of things to look for when you tear down..

At the top of the cylinder feel for a tapper if there isn't one great if there is you've got piston slap which will need to be addressed from a machine shop (assuming it isn't bad) <--Should'nt with your miles.

And look for scoring (Scratches) on the crankshaft. If there is ANY markings either replace it or have it checked by a mechanic.

Summit and Jegs have rebuild kits for our cars, study the parts they supply and simply change them out (In your mind/paper) for performance parts that equal the specs. (Cept Cam)

Out of any performance company I've ever seen TPiS hands down are the best. The service is excellent! (I haven't bought anything yet but they help me to no end via Email) The product is excellent (Read reviews in here) and the Value is excellent (Compare prices!)

www.tpis.com

 

[rrubel]

Oh, I know TPIS... I have their shocks and a number of other goodies including a couple of their performance books - but most of those mods are geared towards strip-only or rarely-driven hotrods. I'm looking for something much more mild.

How mechanically inclined am I? I like to think reasonably so. I've never pulled an engine or transmission though.

Changed the pushrods when I did the roller rockers - put in chrome-moly race-ready ones in preparation for more power.

Pre-built heads - these would then include the valves and springs and stuff already installed?

Thanks.
[RICHR]

 

[Edmond]

I was nosing through the TPIS catalog and came across ported plenums. I think they were $100 or so. But the thing is that you have to use their larger runners which were $500.:eek

 

[BigRed]

Yeah Edelbrock has the Valve train already installed. From what I gather its just a good idea to use a feeler between the Valve and rocker to make sure.

IMHO Im not bothering with the Tube runners (Already had the Plenum done from purchase) ((Not a huge difference))

Im going Miniram plain and simple plus it gives me an excuse to change out the injectors, fuel rail, harness and ECM/PROM

 

[ratorto]

Powerdyne Supercharger

Go to supernatural-performance.com for a complete Powerdyne kit for the C4. About $3k is a good price! LOL

 

[Agent 86]

High miles is 135000. I've replaced normal wear items (water pump, alt, clutch stuff) but nothing inside the engine other than pushrods and rocker arms. How well would a supercharger fit under a stock hood and what would need to be beefed up to prevent internal meltdown? I'm familiar with forced-injection on Subaru's but not really on SBC's.
[RICHR]

Here's my 135,000 timing set. Major slop with cracked and broken nylon teeth. Who knows how long away i was from total failure, but it sure looks like it could have been soon. Put your money into a rebuild.

I had a weird off beat faint knock comming from the bottom end and datamaster went nuts with knock counts when revved. Rather than drive till it drops, i decided to pull it and rebuild it. Iv'e shopped around during the winter and now have all the parts for the rebuild. If you can buy over time you can cut the costs down alot. Ebay, forums etc