86 upgrade questions
Instructor
Joined: May 2006
Posts: 128
Likes: 1
From: KY
Heads
Look at a set of afr 180 eliminator heads or talk to Chad Speier about these heads in a 180cc as a cheaper alternative, he has a proven reputation and will not steer you wrong. He can also mill to your requested 58cc
https://speierracingheads.com/flo-tek-sbc-as-cast.html
https://speierracingheads.com/flo-tek-sbc-as-cast.html
Last edited by c4mo; Apr 12, 2020 at 11:44 PM.
Le Mans Master
Joined: Aug 2015
Posts: 6,092
Likes: 1,972
From: St. Charles MO
If you're going to spend a bunch of money on an intake upgrade, and especially if you're looking at that Comp Cams grind and maybe aftermarket heads; then I would strongly suggest you consider bailing on the TPI concept for intakes and move on to a TPIS Miniram or converted LT1 intake. No matter how big you make the TPI runners (and I think the biggest are actually the FIRST products, not AS&M or TPIS), the in a resonant system like any engine's intake tract the long runners will create an out-of-phase resonance that impedes flow in the runners. You can't get around this without shortening the runners in any practical way. If you stay with TPI-length runners you will cut off at least 1000rpm of usable RPM. That severely limits the power your engine can produce. And the only payoff is a mild bump in power around 2500-3000rpm, which is not especially helpful for going fast. We can cue up the discussions about how "torque" somehow magically makes up for the diminished power. But it doesn't - that's not how physics works.
Thread Starter
Instructor
Joined: Oct 2000
Posts: 190
Likes: 10
From: southern new jersey
Thanks Matt I appreciate your input. I realize the drawbacks for sure, the SuperRam does have shorter runner lengths to help with that. I am not looking for a high RPM engine. It being the low mileage original I don't really want to get much above maybe 5500 and will be happy if I can get to that point making some power. I did see however a member that had made a single plane intake into a FI intake and put a 90 degree ell with a throttle body on it...…….. I'm sure it was a better mouse trap and it looked pretty cool besides. If I was going for a higher reving engine I would definitely get a MR. I played with DeskTop Dyno at a friends house...it was an older version and didn't have the SuperRam listed as an intake option. He just sent for an update. whether it has the SuperRam in there who knows, hope it does to see how the curves would change.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Yea, to keep your compression up your gonna need tight chamber heads like your stock 58cc heads. So I find TrickFlow has heads with 56cc chambers and 175cc runners but I can't tell you which one of the 6 part number will work on a 1986 corvette TPI. It might beTFS-30310003 or TFS-30310006 or TFS-30310001 so you would have to verify with TrickFlow. But the TrickFlow heads are just over $1100 for a pair.
Wow! You have a super ram. Those are so hard to find it makes me jealous. And a Dana 44 with 3.45 gears to boot. That SR and gearing will allow much longer duration cam than 219 (@ 0.050"). Try a Comp Cams XFI 224/231 (#268XFI H13).
Hope this helps.
Wow! You have a super ram. Those are so hard to find it makes me jealous. And a Dana 44 with 3.45 gears to boot. That SR and gearing will allow much longer duration cam than 219 (@ 0.050"). Try a Comp Cams XFI 224/231 (#268XFI H13).
Hope this helps.
Le Mans Master
Joined: Aug 2015
Posts: 6,092
Likes: 1,972
From: St. Charles MO
Thanks Matt I appreciate your input. I realize the drawbacks for sure, the SuperRam does have shorter runner lengths to help with that. I am not looking for a high RPM engine. It being the low mileage original I don't really want to get much above maybe 5500 and will be happy if I can get to that point making some power. I did see however a member that had made a single plane intake into a FI intake and put a 90 degree ell with a throttle body on it...…….. I'm sure it was a better mouse trap and it looked pretty cool besides. If I was going for a higher reving engine I would definitely get a MR. I played with DeskTop Dyno at a friends house...it was an older version and didn't have the SuperRam listed as an intake option. He just sent for an update. whether it has the SuperRam in there who knows, hope it does to see how the curves would change.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Now that I looked at post #14 again that crower cam 00231 looks good to.
Something about heads I want to add is now that you have a super ram you need heads with the bolt pattern that matched the super ram. You need to find out what bolt pattern the SR has and select heads that match it - that is if your going with new heads. But those TrickFlow heads have a price that's hard to beat and have the right chamber size.
Good luck.
Something about heads I want to add is now that you have a super ram you need heads with the bolt pattern that matched the super ram. You need to find out what bolt pattern the SR has and select heads that match it - that is if your going with new heads. But those TrickFlow heads have a price that's hard to beat and have the right chamber size.
Good luck.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo