silver86

Well, the car hasn't sold as is, so I'm going to go back naturally aspirated and sell the blower and compenents. I'm considering dumping the tpi in favor of either a modded LT1 intake, or the Miniram. I'm just up in the air on the combination I should run, and if I should keep the AFR 195's or not. Getting rid of the blower, intake, trans, and heads allows me to upgrade other areas (brakes, gears, etc.) .I'm not a cam expert, so that's where I probably need the most help, but I'm definitely going hydraulic/roller though. The car will be almost all street, with occasional track fun. And I'm looking at stepping up to a 3.07 or higher rearend depending on the build. I always run premium fuel anyway, so no issues there.

I know almost nothing about dynamic compression ratios, and what's an acceptable target (~8.4:1?), so I'm just taking a stab. I'm feeling a cost limit here of around $1500-$2000, that should net me a $3000 surplus after I sell the FI and intake items. Also, I'm kicking arount the idea of jumping to a 1.7rr, instead of the 1.6's I currently have. I'm targeting maybe 375-400 chp (tough to get on the TPI).

Here are the options that I've been contemplating:

Things I have:
short block is a 1986E L98 - stock
58mm TB
2,500 rpm 9.5" stall
AFR 195's 65cc
LT TPIS Headers
Currently 2.59 rear

Without TPI style intake

Option 1:

AFR 195's 65cc (.600 max lift)
LT1 intake
58mm TB
Static CR: w/.018 compressed 9.91:1 (.043 quench)
max target rpm 6,500
Cam?
Crane 119831
222/230 @ .050, 112 Lobe sep
.509/.528 @ 1.5 (.542/.563 @ 1.6) (.576/.598 @ 1.7)
3.54


Option 2:

113 Aluminum heads (58cc if I remember right)
Miniram intake
58mm TB
Static CR: w/.018 compressed 10.75:1 (.043 quench)
max target rpm 6,500
LT4 Hot Cam?
3.54


Option 3:

113 Aluminum heads (58cc if I remember right)
LT1 intake
58mm TB
Static CR: w/.018 compressed 10.75:1 (.043 quench)
max target rpm 6,000
LT4 Hot Cam?
3.54
Cheap build


With TPI style intake

Option 4:

AFR 195's 65cc (.600 max lift)
TPI Intake (TPIS Big Mouth, SLP runners, ported plenum)
58mm TB
Static CR: w/.018 compressed 9.91:1 (.043 quench)
max target rpm 5,200
Cam?
3.07

Option 5:

113 Aluminum heads (58cc if I remember right)
TPI Intake (TPIS Big Mouth, SLP runners, ported plenum)
58mm TB
Static CR: w/.018 compressed 10.75:1 (.043 quench)
max target rpm 5,200
Cam?
3.07
Cheapest build

cardo0

Ok i'll give it try. Option 5!

More compression will make a bigger cam work so my vote is for the 113 alum heads. Even though the big AFR's flow like hell they need more cubes, more compression and more cam than u have for them to make big power. A little porting will wake those 113 heads up if u have an extra $1k or maybe less. Try: Performance Chevy Products, (602) 254-9586, 2995 W Whitton Ave, Phoenix, AZ 85017. Performance Chevy has the best deal on head work that i know of.

Next choice is for the TPIS intake and SLP runners. These should out preform the LT1 intake through out the power band except for maybe the very top end. And the LT1 would need porting to match 113 head intake runners.

Cam? I would run a tight cam with 108 degree lobe separation angle for max torque through out power band (110* LSA if 113 heads get ported and 1.6 rockers). Yes idle will be rougher and u lose some top rpm but this will match the long TPIS/SLP runners much better. Most cams for sb chevy are 110* LSA or greater so u may need to order special for a hyd roller. Duration at 0.050" should be less than 225*. And with free flowing dual exh with good headers a single pattern cam should be fine unless u still have the stock cats then add 'bout 5* duration to the exh. U need to shop for a cam yourself as that is really a good part of the fun a perf engine build.

I don' know what a Pete K transmission is so u will need to determine your rear gear needs from your tire size and first gear ratio for accelerator or your top gear ratio for cruise rpm. But i would do this mod last after u find how eng performs with new mods.

Hope this helps and good luck.
Please post your results,
cardo0

mr.beachcomber

YMMV, but before you do a rebuild, I would recommend deciding on what you want most, street-ability or top end power. Your AFR heads need to breathe to make power so you've added a 58 mm throttle body, yet you're running a MAF system that flows a nominal 530 CFM in stock form. You have a 2500+ RPM stall converter and a stock 2.59 rearend. You're not replacing the stock pistons, but trying to achieve a 10.75:1 compression ratio by using a steel shim gasket that probably won't seal the heads properly and may even brindle (indent) them in the process. You're not decking the block, so you're taking a chance of leaning out the air/fuel mixture under acceleration not to mention that the Crane PowerMax cam (designed to produce power above 2000 RPM) you specified won't work with a stock ECM w/o a custom chip and lots of tuning.

If you're looking for a streetable Vette, I would recommend upgrading to a 3.07 Dana 36 rearend, and installing a 2000+ RPM stall converter with lock-up for overdrive. You can upgrade the TPI intake manifold and runners to flow better with a modified, aftermarket MAF (good for about 750 CFM). Unless you had the AFR heads CNC ported, they should flow best around 0.55" of lift. Your 1.6 RR should handle that fine. (I won't go to 1.7 RR w/o first checking with AFR to see what mods they would recommend to keep the valve train geometry.) Talk with Competition Cams about their hydraulic roller cams for computer controlled cars. I think that you'll find that either their 08-304-8 or their 08-305-8 cam will fit the bill.

If you decided to go the top end horsepower route, I think that you will need to deck the block and install aftermarket pistons to complement the cam you choose and well as chip the ECM. Comp Cams make a great cam for power in the 2000-6000 RPM range for computer controlled cars. It's 08-306-8. If you go this route, keep the 2500+ RPM stall converter and go for an aftermarket Dana 36 with 3.54 gears. Again, free up the intake system from the MAF to the manifold and runners to match the flow required for the HP.

Hope this info helps. Good luck with the build.

ZD1

a few notes:
like previous posts know what you want and then build a motor for it, seems like just a little more fun. But sense you are taking off the s/c...nothing for less than $10K is going to compare.

I'll assume that you have tuning capabilities (tuner, after market ecu, etc...)

there's no difference between 1.6 and 1.7's...as long as they are good quality. The 1.7's will be more lift, but I haven't seem too many for sbc. Just get a cam with enough lift for the 1.6's adn save the dough


dyn compression...real dyn compression can only be measured (function of cam and RPM). Static CR for cast iron is 9-9.5...10-10.5 for aluminum. Tighter tuning can net for cr for al heads and lopier cams. i ran 11.8 with my 383. (for FI cr's need to be 8.5ish).

if you to keep a little fun, add a converted lt1 or edelbrock intake ($450), 224/224 cam on 112 with .550" lift ($450? with lifters), keep the afr heads.

if you have the original stuff (intake, emissions, ) return to stock. drive it or sell it.

or just part out the whole thing