Dyno Results
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Joined: Jul 2003
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From: DFW Texas
Dyno Results
Went to Speedtek Dyno Day today. Here are the results:
273.8HP @4500rpm
360.1T @3500rpm
Engine and mods:
1991 L-98. Mods: AFPR(50psi), TB airfoil, TB bypass, Remove Frisbee, Advance timing to 8 deg., cut air lid, K&N filter, 2 1/2 mandrel bent exhaust, no pre cats, trans shift kit, edelbrock TPI runners, Accel intake, ported heads and plenum, low temp fan switch, underdrive pulleys, 1.6 rockers
A/F was 11.5:1 @ 4000rpm to 12.5 @ 4900rpm
The car blew black smoke out of the tailpipes on the first run. It wasn't as bad on the next two runs. The tech guy also said that he heard it detonatiing at low rpm. I have now backed the timing to 6 deg initial and the FP to 45.
I would post the scan of the runs but photohost isn't working right now. What parameters would a new chip control on one of these old cars? I guess I'm trying to see if it would be worth it to have one burned.
273.8HP @4500rpm
360.1T @3500rpm
Engine and mods:
1991 L-98. Mods: AFPR(50psi), TB airfoil, TB bypass, Remove Frisbee, Advance timing to 8 deg., cut air lid, K&N filter, 2 1/2 mandrel bent exhaust, no pre cats, trans shift kit, edelbrock TPI runners, Accel intake, ported heads and plenum, low temp fan switch, underdrive pulleys, 1.6 rockers
A/F was 11.5:1 @ 4000rpm to 12.5 @ 4900rpm
The car blew black smoke out of the tailpipes on the first run. It wasn't as bad on the next two runs. The tech guy also said that he heard it detonatiing at low rpm. I have now backed the timing to 6 deg initial and the FP to 45.
I would post the scan of the runs but photohost isn't working right now. What parameters would a new chip control on one of these old cars? I guess I'm trying to see if it would be worth it to have one burned.
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
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You are making 320-330chp so I'm surprised that you were running that rich with only 50psi of fuel pressure. I assume that was measured with the vacuum line disconnected.
It looks like you are running stock headers & cat.
Since you have done intake & heads as well as some valve train work you will really benefit from FL headers and a hi-flow cat.
I think it would be beneifcial to finish up exhaust, install a fuel pressure gauge and tune the system with another set of dyno pulls. Then you can consider a custom chip if needed.
It looks like you are running stock headers & cat.
Since you have done intake & heads as well as some valve train work you will really benefit from FL headers and a hi-flow cat.
I think it would be beneifcial to finish up exhaust, install a fuel pressure gauge and tune the system with another set of dyno pulls. Then you can consider a custom chip if needed.
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From: DFW Texas
Thanks 65Z01. I guess I forgot to add a copule of included mods. I have upgraded valvesprings, titanium retaners, and 7/16 studs on the heads. I also have a new hi flow cat that was installed when I put the 2 1/2 exhaust on. I also welded on the factory SS exhaust manifolds so I could port out the interior welds especially at the top of the ports. I also ported out the exit of the manifolds to 2 1/2 to match the exhaust. I agree that FL headers would help but I really don't want to wrestle with the things. Too much history with headers in the past, i.e. starter clearance, hot floorboards, ill fitting, etc... I may consider cahnging cams in the future and maybe a torque convertor change. I guess next step is, as you suggest, really spending some time working on the tune on the dyno. Thanks 
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
I too ported my stock shortie heades, ie cut off the EGR & AIR tubes inside the header pipes and opened up the tub inlets to more closely match the D ports. However, the effect was not enough to be seen in trap speed.
Meanwhile Vic'89, who was running the same exhaust setup as me, added FL coated headers and gained about 17chp.
You've built up your valve train about the same as mine; I too went with Ti retainers & 7/16" studs for better high RPM control.
A good cam should give you another 30chp and then the headers might be worth 20 chp or so. That would put you very close to 390chp, about the best to expect from a worked TPI. Maybe Al underdrive pulleys and cut-back plugs would push it to 400chp.
Did you have the #113s fully ported or pocket ported; what size valves?? I'm asking because I would like to port my stock heads in the future.
Good luck with the dyno tuning.
Meanwhile Vic'89, who was running the same exhaust setup as me, added FL coated headers and gained about 17chp.
You've built up your valve train about the same as mine; I too went with Ti retainers & 7/16" studs for better high RPM control.
A good cam should give you another 30chp and then the headers might be worth 20 chp or so. That would put you very close to 390chp, about the best to expect from a worked TPI. Maybe Al underdrive pulleys and cut-back plugs would push it to 400chp.
Did you have the #113s fully ported or pocket ported; what size valves?? I'm asking because I would like to port my stock heads in the future.
Good luck with the dyno tuning.
Last edited by 65Z01; Nov 27, 2004 at 11:41 PM.
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From: DFW Texas
That's intersting about your header experience. I may have to reconsider. I may have gotten the idea about porting my headers from you. Most of my mods have come from reading up on what you guys have already done. Why reinvent the wheel?
My buildup has been on the cheap. I tried to put my money into parts that could carry me into the future(and hopefully faster). I pocket ported my own heads and reused the stock valves. The valves were already back cut so I just lapped them in before reassembly. I have done this many times with 1.94 cast iron heads on other cars and have picked up 3 tenths in the 1/4 mile. I am sure bigger valves would have helped but I can't see putting money into these castings.
One problem I came across is corrosion of the coolant passages in the heads. Several of mine had eroded into the head gasket compression ring and would not seal. I wound up with antifreeze in my oil. I had to repull the heads and have the passages welded and the heads resurfaced. I am told that this errosion is a common problem on these 113 heads. One other thing, I am using a .021 head gasket. Good luck with yours as well.
My buildup has been on the cheap. I tried to put my money into parts that could carry me into the future(and hopefully faster). I pocket ported my own heads and reused the stock valves. The valves were already back cut so I just lapped them in before reassembly. I have done this many times with 1.94 cast iron heads on other cars and have picked up 3 tenths in the 1/4 mile. I am sure bigger valves would have helped but I can't see putting money into these castings.
One problem I came across is corrosion of the coolant passages in the heads. Several of mine had eroded into the head gasket compression ring and would not seal. I wound up with antifreeze in my oil. I had to repull the heads and have the passages welded and the heads resurfaced. I am told that this errosion is a common problem on these 113 heads. One other thing, I am using a .021 head gasket. Good luck with yours as well.
Race Director
Joined: May 2003
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Originally Posted by Runum
Went to Speedtek Dyno Day today. Here are the results:
273.8HP @4500rpm
360.1T @3500rpm
Engine and mods:
1991 L-98. Mods: AFPR(50psi), TB airfoil, TB bypass, Remove Frisbee, Advance timing to 8 deg., cut air lid, K&N filter, 2 1/2 mandrel bent exhaust, no pre cats, trans shift kit, edelbrock TPI runners, Accel intake, ported heads and plenum, low temp fan switch, underdrive pulleys, 1.6 rockers
A/F was 11.5:1 @ 4000rpm to 12.5 @ 4900rpm
The car blew black smoke out of the tailpipes on the first run. It wasn't as bad on the next two runs. The tech guy also said that he heard it detonatiing at low rpm. I have now backed the timing to 6 deg initial and the FP to 45.
I would post the scan of the runs but photohost isn't working right now. What parameters would a new chip control on one of these old cars? I guess I'm trying to see if it would be worth it to have one burned.
273.8HP @4500rpm
360.1T @3500rpm
Engine and mods:
1991 L-98. Mods: AFPR(50psi), TB airfoil, TB bypass, Remove Frisbee, Advance timing to 8 deg., cut air lid, K&N filter, 2 1/2 mandrel bent exhaust, no pre cats, trans shift kit, edelbrock TPI runners, Accel intake, ported heads and plenum, low temp fan switch, underdrive pulleys, 1.6 rockers
A/F was 11.5:1 @ 4000rpm to 12.5 @ 4900rpm
The car blew black smoke out of the tailpipes on the first run. It wasn't as bad on the next two runs. The tech guy also said that he heard it detonatiing at low rpm. I have now backed the timing to 6 deg initial and the FP to 45.
I would post the scan of the runs but photohost isn't working right now. What parameters would a new chip control on one of these old cars? I guess I'm trying to see if it would be worth it to have one burned.
have a dyno graph, real impresive numbers, especially the torque......
Race Director
Joined: May 2001
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Originally Posted by Runum
Too much history with headers in the past, i.e. starter clearance, hot floorboards, ill fitting, etc...
Hell they bolt right up on my LT1 and they weren't even designed for that engine!
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Joined: Jul 2003
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From: DFW Texas
OK I finally got the dyno sheet scanned. I have been reading many threads on dyno results. I am confused as to what A/F ratio I am looking for to get max. performance at WOT. Do my A/F results look that bad on paper?
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Race Director
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Most normally aspirated cars tend to make peak power in the 12.5:1 to 13.0:1 range. I usually try to shoot for 12.8:1 on my car.
Every car is slightly different, not so much that the engine really requies anything different, but rather exhaust leaks and such can skew the wide band a little bit one way or the other.
Every wide band is gonna be slightly different in it's calibration too, so one dyno might not correllate exactly with another. As such there are too many variable to say exactly what A/F you should shoot for.
Looking at your graphs though I'd have to say you're running a bit rich yet. Lean it out some and you'll probably find a few more ponies.
Every car is slightly different, not so much that the engine really requies anything different, but rather exhaust leaks and such can skew the wide band a little bit one way or the other.
Every wide band is gonna be slightly different in it's calibration too, so one dyno might not correllate exactly with another. As such there are too many variable to say exactly what A/F you should shoot for.
Looking at your graphs though I'd have to say you're running a bit rich yet. Lean it out some and you'll probably find a few more ponies.
Burning Brakes
Joined: Aug 2000
Posts: 1,146
Likes: 2
From: Albuquerque NM
Went to Speedtek Dyno Day today. Here are the results:
273.8HP @4500rpm
360.1T @3500rpm
The car blew black smoke out of the tailpipes on the first run. I
You're pretty close to the limits of the TPI. Depending on your cam, I would run to get a custom chip made. If you just the stock cam, i'd start walking at a brisk pace. If you have the CAM that the motor deserves, I'd reant a Uhaul and tow the car to a competent tuner.
273.8HP @4500rpm
360.1T @3500rpm
The car blew black smoke out of the tailpipes on the first run. I
You're pretty close to the limits of the TPI. Depending on your cam, I would run to get a custom chip made. If you just the stock cam, i'd start walking at a brisk pace. If you have the CAM that the motor deserves, I'd reant a Uhaul and tow the car to a competent tuner.
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Originally Posted by Runum
Went to Speedtek Dyno Day today. Here are the results:
273.8HP @4500rpm
360.1T @3500rpm
Engine and mods:
1991 L-98. Mods: AFPR(50psi), TB airfoil, TB bypass, Remove Frisbee, Advance timing to 8 deg., cut air lid, K&N filter, 2 1/2 mandrel bent exhaust, no pre cats, trans shift kit, edelbrock TPI runners, Accel intake, ported heads and plenum, low temp fan switch, underdrive pulleys, 1.6 rockers
A/F was 11.5:1 @ 4000rpm to 12.5 @ 4900rpm
The car blew black smoke out of the tailpipes on the first run. It wasn't as bad on the next two runs. The tech guy also said that he heard it detonatiing at low rpm. I have now backed the timing to 6 deg initial and the FP to 45.
I would post the scan of the runs but photohost isn't working right now. What parameters would a new chip control on one of these old cars? I guess I'm trying to see if it would be worth it to have one burned.
273.8HP @4500rpm
360.1T @3500rpm
Engine and mods:
1991 L-98. Mods: AFPR(50psi), TB airfoil, TB bypass, Remove Frisbee, Advance timing to 8 deg., cut air lid, K&N filter, 2 1/2 mandrel bent exhaust, no pre cats, trans shift kit, edelbrock TPI runners, Accel intake, ported heads and plenum, low temp fan switch, underdrive pulleys, 1.6 rockers
A/F was 11.5:1 @ 4000rpm to 12.5 @ 4900rpm
The car blew black smoke out of the tailpipes on the first run. It wasn't as bad on the next two runs. The tech guy also said that he heard it detonatiing at low rpm. I have now backed the timing to 6 deg initial and the FP to 45.
I would post the scan of the runs but photohost isn't working right now. What parameters would a new chip control on one of these old cars? I guess I'm trying to see if it would be worth it to have one burned.
did u notice and gains with the underdrive pulleys? and what one's do u have?
also a AFPR 
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From: DFW Texas
Thanks for the input guys. It lets me know I'm heading in the right direction. I do already have AFPR and have dialed the FP back to 45 until I get to run it again on the dyno. As far as the pulleys, I installed them with the rest of the stuff so I have no A-B-A testing results to contribute. I bought a steel crank and WP pulley on this forum. I ordered a real small alt. pulley off of the internet, don't know where right off hand.
On the header thing, man I'm old. I still remeber getting new headers for $50-$80 a set. Now I see prices from $360-$700 for HEADERS?
Then I see exhaust systems $700+. I guess I will probably put headers on it eventually.
It does still have the stock cam in it with 1.6 rockers.
The question I still have is what would a new prom change? The fuel curve and spark curve?
On the header thing, man I'm old. I still remeber getting new headers for $50-$80 a set. Now I see prices from $360-$700 for HEADERS?
Then I see exhaust systems $700+. I guess I will probably put headers on it eventually.It does still have the stock cam in it with 1.6 rockers.
The question I still have is what would a new prom change? The fuel curve and spark curve?
Last edited by Runum; Nov 30, 2004 at 05:59 PM.
Safety Car
Joined: Jun 2000
Posts: 4,870
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From: Long Island, NY
Forget porting the stock manifolds, 65Z01 didnt get much of a gain.
Header will wake your car up big time. I bet atleast 20 RWHP with headers. The Hookers 2149's cost in the $500 range.
You have 2 HP more than me.
Good luck.
Vic
Header will wake your car up big time. I bet atleast 20 RWHP with headers. The Hookers 2149's cost in the $500 range.
You have 2 HP more than me.
Good luck.
Vic