Background: I just inherited an 89 Caprice with L03 & only 130000km (80000mi), body & interior in great shape. Mechanically in great shape, 2.73 gears & either a 220-4R or 700R4 tranny, (not sure).

Wish to do: use as a daily driver that will see the highway far more than the strip but jack up the fun factor by creating an old sleeper....will not be doing the bling thing to the exterior. Engine will not be replaced or removed from car for any mods. Probably not going to see high RPM use, modded appropriately...5500 RPM? Likely no rear gear changes to keep good mileage....minimal, if any, tranny mods unless required. TBI stays.

Thoughts:
1) Exhaust..add LT headers (thinking Summit ...coated?...brand since seem far more cost effective than name brand, fab a Y, into 3 inch single exhaust, no cat or air, low flow muffler. Headers back would probably be the most expensive mod of all & done 1st. Should have no clearance problems since it's a B body????
2) replace stock air cleaner with dual snorkel & home brew CAI..done at same time as exhaust.
3) get all required stuff to start data logging and DIY chip tuning.....actually this would be step #1 so I can get a base line and be familiar with the process...already read many of the stickies
4) do the ultimate TBI mods as required & obtain larger injectors (suggestions as to size??) and obtain larger capacity fuel pump. Can a 2nd pump be placed in line with a WORKING stock in tank unit or must the new pump go in tank...I'd obviously like to avoid this job.

Now for stuff I REALLY need input on...

5) Heads...the stock 187's from what I read on this board can actually flow pretty good with a little DIY porting as long as you don't expect high RPM performance...and I don't. As an alternative will the 081 heads from a 87+ TPI be a direct bolt on and be a better head choice, also with some DIY porting? All other choices from what I've read seem to mean a lot more $$$$ & alterations to work...Vortecs, etc. Any suggestions pro, con or alternatives?

6) Manifold....see many people like the performer series over the stock. I've read that the TBI performer really isn't much of an improvement..true? The RPM version seems to be the preferred choice but I will require an adaptor I believe for the TBI unit. Since this is a B body the stock hole in the manifold for the distributor is not large enough & needs to be enlarged....true?? I looked on the Summit site & couldn't decide which PART NUMBER was the best choice...anyone? Are there other manifolds that offer an improvement and can be bolted on ... from other GM models?? Suggestions..thoughts?

7) Cam..the easiest/cheapest to obtain that offers reasonable gains and requires no head mods due to lift seems to be the 93-95 LT1 cam #12551705...true?? Since this install is the most difficult due to rad removal etc the cam would be my last mod. Reasonable? Or is there no point in doing a manifold/head swap without the cam??

Sorry for the long post & many questions but I would like input BEFORE I try to collect parts and do any work. I have already read the budget 350 build post which was very good info, but it dealt with a Vortec 350.

Thanks in advance for any thoughts, suggestions and most importantly...parts numbers.

 

First off, this is a third gen F-body site. Second, one of the first things you want to do is take your 2.73s and throw them as far away as you can, preferably into the back of a truck going far away. Third, you'd need to pull the engine out to swap the cam, unless you're pulling apart the front end, so that's out because you won't pull the engine. I highly doubt that without very well ported stock heads, cam and high performance intake you'll need to get a better flowing TBI unit or bigger injectors. Likewise, unless your stock fuel pump is on the way out, you don't need a higher flow model. Aside from that, you're left with exhaust, which is a good idea. So is a dual snorkel intake. The deeper into your car you're willing to dig, and the more you're willing to spend, the faster you'll get.

 

You'll find much more info on a site designed for your specific interests.

JamesC

 

JamesC & 84Z28406

Yes, I do realize this site is primarily 3rd gen F bodies but there are many other valued contributors with other cars on the site. The reason I posted here is because this site has BY FAR the most useful info for these engines & TBI tuning. My questions & request for info was not specific for the B body except for the intake manifold hole for the distributor. The others I believe are universal.

in car cam swap I realise requires front end parts removal but is probably less work than engine removal. See here
https://www.thirdgen.org/forums/tbi/...-ultimate.html

Since the questions I'm asking were from info found on the TBI parts of the site perhaps one of the mods could move this thread to a more appropriate area....if possible.

Thanks for replies given.

Regards

 

First off a see no reason why 89caprice should go elsewhere for help, we are all chevy guys at heart are we not?

As far as the priority of performance modifications is concerened, i would rate rear-end gears lower on the list than cam, headers, intake. my reasoning lies in the large cost associated with properly installing a new set of gears. you have to purchase them first, and then have them installed by a professional, all for a very small gain in performance (at your very mildly modified level). I think your money and effort would be better spent pulling the engine (i'm not sure of your experience level, but its no where near as difficult as it sounds) to facilitate some general maintenance, and the installation of a decent cam (i'm thinking a bit bigger than the lt1 cam). perhapes refresh the ignition system with an MSD ready-to-run streetfire dizzy. buy some cheapie headers off summit. and hit the road.

here are some links:

MSD distributor
http://store.summitracing.com/partdetail.asp?autofilter=1∂=MSD-8362&N=700+115&autoview=sku

Summit intake manifold (rebranded weiand action+ manifold)
http://store.summitracing.com/partde...8&autoview=sku

A mild cam from comp (i have had good results using cams with similar duration/lifts in mild-stock engines)
http://store.summitracing.com/partde...8&autoview=sku


-Zander

 

The reason I mention that this is a third gen site is because I've seen threads get locked for not being third gen related. I realize we share this motor, but if the thread is locked, that'll be why. As for rear end gears not being worth it, I disagree. Most cams like more rear gear, and as far as how quick the car gets up and gone, a set of 3.42s or 3.73s will give a pretty decent improvement. I wouldn't spend money on an aftermarket distributor at this point, prefering instead to spend the money elsewhere and just replace the wear parts with stock replacement, cap, rotor, wires, plugs. The zander is right though, pulling the engine isn't terribly hard, as long as you have an engine hoist. Try looking for one in a local buysell type mag.