Dyno'd today, thanks Locobob.

[efnfast]

Hit the dyno again today. After installing the new to me, ported plenum and IH, done by Locobob, I'm up 44 hp.

[We Gone]

Congrats....Nice gain. What were the numbers?

[KILLSHOTS]

Are you serious? Porting the plenum and IH gave you a NET 44 hp? You gained over 10% of the overall HP of the LT5? At the wheels? You ran it on the dyno immediately before and after this mod?

[efnfast]

Congrats....Nice gain. What were the numbers?

I was 353 at the wheels before, actually 2 years ago. Early this winter, bought a ported plenum and injector housing form Locobob, also did injectors and coils. Today, dyno'd at 397 rwhp.

Did a couple of other runs.

When I bought the car with a K&N, dyno'd at 311.
Did headers and exhaust, 353.
Ported P & IH, 397.
Key off today, 247, exactly 150 hp loss.
Accordion pulled, get this, 386, lost power.
Next is a visit to Pete.

Steve

PS, next on the dyno was a 1,000 hp Mustang.

[efnfast]

Are you serious? Porting the plenum and IH gave you a NET 44 hp? You gained over 10% of the overall HP of the LT5? At the wheels? You ran it on the dyno immediately before and after this mod?
Couple of years in between, but that was the major mod, other than injectors that were not giving me trouble. It all started with doing injectors, next thing you know i'm investing in a powder coated plenum and IH.

[1990 quasar blue]

Nice numbers. Whole new world isn't it? Did you go with OBX all the way back? Also, just curious if the numbers were SAE or STD?
Congrats on the new power.

[KILLSHOTS]

Couple of years in between, but that was the major mod, other than injectors that were not giving me trouble. It all started with doing injectors, next thing you know i'm investing in a powder coated plenum and IH.
That's an impressive gain. Would you say the SOTP gain was greater when you added headers/exhaust or when you added the ported plenum/IH?

[efnfast]

Nice numbers. Whole new world isn't it? Did you go with OBX all the way back? Also, just curious if the numbers were SAE or STD?
Congrats on the new power.

OBX ceramic coated headers and OBX exhaust.
SAE adjusted, but it was a perfect day and there was no correction. -Steve

[efnfast]

Hard to say on SOTP, it was almost 6 months in between drives with the new top end parts. Also should add, Marc chip done with exhaust, and redone for the porting. Marc may have gotten a little aggresive, we think we saw some detonation at between 6k and 6500. -Steve

[Mystic ZR-1]

Steve
You're up early?
Doug

[XfireZ51]

Hard to say on SOTP, it was almost 6 months in between drives with the new top end parts. Also should add, Marc chip done with exhaust, and redone for the porting. Marc may have gotten a little aggresive, we think we saw some detonation at between 6k and 6500. -Steve

I'd be surprised about that. Did you run a WB O2 with the runs? Detonation usually happens somewhere right around torque peak. Likely why u see a bit of a sag in the torque curve at the rpm before it continues further up.

[efnfast]

I'd be surprised about that. Did you run a WB O2 with the runs? Detonation usually happens somewhere right around torque peak. Likely why u see a bit of a sag in the torque curve at the rpm before it continues further up.

We had some fluttering in the curve at top end. He suspected detonation. A/F was about 12.5 when it happened. Didn't feel it, just see it on the curve.

[XfireZ51]

We had some fluttering in the curve at top end. He suspected detonation. A/F was about 12.5 when it happened. Didn't feel it, just see it on the curve.

You will usually see "fluttering" especially at top end. There's fluctuations that could have something to do w traction on the roller etc. There's also "smoothing" which is part of the software. I've bumped my timing up to 34d+ at top end and motor did not detonate, it just dropped in power. I'm pretty sure Marc's cal is more conservative than that. 12.5 is a bit fat IMO, but that will also be dependent on whether the overall tune is rich or lean. I'd also want to see what plugs look like.

[efnfast]

You will usually see "fluttering" especially at top end. There's fluctuations that could have something to do w traction on the roller etc. There's also "smoothing" which is part of the software. I've bumped my timing up to 34d+ at top end and motor did not detonate, it just dropped in power. I'm pretty sure Marc's cal is more conservative than that. 12.5 is a bit fat IMO, but that will also be dependent on whether the overall tune is rich or lean. I'd also want to see what plugs look like.
Thanks Dom, eases my mind to think I'm not detonating at 6 grand.

[1990 quasar blue]

OBX ceramic coated headers and OBX exhaust.
SAE adjusted, but it was a perfect day and there was no correction. -Steve

Thanks. If you want to meet up in epping one day let me know.

[XfireZ51]

Thanks Dom, eases my mind to think I'm not detonating at 6 grand.

Steve,

Obviously you pull a few plugs and just make sure there's no aluminum pitting in the ceramic.

[efnfast]

Thanks. If you want to meet up in epping one day let me know.
Where in MA are you?

[efnfast]

Dom, the plugs look to have sort of a grey color to them. The two I pulled have gone from the .0050 (at Marc's recomendation) to .0060. Iridium plugs.

[1990 quasar blue]

Where in MA are you?

South coast. About 1/2 hour from the cape.

[efnfast]

South coast. About 1/2 hour from the cape.
Headed to Worcester next weekend.
Epping to watch the races, or Epping to race? -Steve

[1990 quasar blue]

Headed to Worcester next weekend.
Epping to watch the races, or Epping to race? -Steve

I could certainly be tempted to make a few passes if you're interested. I've only been a couple of times. Once they cut it back to 1/8 mile due to wind and the last time it was 42' and I reinvented the sit N spin.

[efnfast]

I could certainly be tempted to make a few passes if you're interested. I've only been a couple of times. Once they cut it back to 1/8 mile due to wind and the last time it was 42' and I reinvented the sit N spin.
Never done the quarter mile. I think Wednesday is run what you brung.

[1990 quasar blue]

Never done the quarter mile. I think Wednesday is run what you brung.

I'm much more of a back roads guy myself. I believe you're correct about wednesdays. The middle of the week could be a little tough for me as it's an hour and a half each way without traffic. Although, I could always take the day off as opposed to driving up after. Let me know what you're thinking.

[efnfast]

I wasn't thinking anything until you brought it up. My schedule is easy, own my own business. Let me know if it's worth the trip up, and the day off.

[1990 quasar blue]

I wasn't thinking anything until you brought it up. My schedule is easy, own my own business. Let me know if it's worth the trip up, and the day off.

Ok. Good to know. Looks like wednesdays and fridays are pretty much the same for them. I'll shoot you a pm in a week or so. Definitely worth the trip.

[Locobob]

That's excellent Steve, glad you are happy with my work. Headers, exhaust and intake porting really work well together - each compliments the other and you'll only see the full potential of each when combined. From my dyno experience a little knock retard in the 4K range is pretty normal and hard to eliminate, if it doesn't recover quickly or comes on in the higher rpms then I'd work on your tuning some more. 12.5 should be plenty safe for A/F.

[efnfast]

At some point, hopefully in the near future, will be head work and a custom tune.
Any headway on the set I sent you Robert?

[Locobob]

At some point, hopefully in the near future, will be head work and a custom tune.
Any headway on the set I sent you Robert?

Zero.... fighting like mad to get my interior project wrapped up so I can salvage a little bit of the driving season. I blame "while I'm there" syndrome lol

[efnfast]

Understand the while I'm in there" problem.
I started out doing injectors, but while I'm in there, lets do coils and wires and starter, might as well buy a ported plenum and injector housing while I'm in there. Might as well have them powder coated too.

[XfireZ51]

Zero.... fighting like mad to get my interior project wrapped up so I can salvage a little bit of the driving season. I blame "while I'm there" syndrome lol

Know it all too well Robert.

[efnfast]

More mods, another dyno run today.

[BlackSheepz]

More mods, another dyno run today.

So? How did it go?!

[efnfast]

Cams, ported heads, open up the plenum and IH more, 15# flywheel, lite weights pulleys.
451 rwhp, 403 rwtq.
520 hp figuring 15% loss.
Running a little lean, hit a peak of about 13.9 a/f.

[XfireZ51]

Cams, ported heads, open up the plenum and IH more, 15# flywheel, lite weights pulleys.
451 rwhp, 403 rwtq.
520 hp figuring 15% loss.
Running a little lean, hit a peak of about 13.9 a/f.

Definitely fatten it up. What was the correction factor used for the dyno?
SAE, Standard, Actual? Dynojet or Mustang?

[efnfast]

Dom, it was SAE corrected.
Land and Sea dyno that he tells me runs very close numbers to the Dynojet.
I think when he corrected to Standard I was about 478 rwhp, or 562 hp. I like those numbers. Next time I'm going to ask him to do it in first, just for the fun of it.

[efnfast]

When I talked to Pete about the 13.9, he custom tuned with a bung on the headers, the dyno guy used a sniffer in the end of the tail pipe. So there might be some discrepancy there.

[George Maz]

For mostly the same mods, my #1727 car puts down 434rwhp, 366 rwtq on the dynojet. And a consistent 400hp on Mustang dyno. I'd say you did pretty good.
...must be those new Fog lights giving you the extra ponies...lol

[efnfast]

For mostly the same mods, my #1727 car puts down 434rwhp, 366 rwtq on the dynojet. And a consistent 400hp on Mustang dyno. I'd say you did pretty good.
...must be those new Fog lights giving you the extra ponies...lol
George, do you have cams?
The fog lights are great, working on the headlights.

[Pete]

Hi Steve
Those are good numbers now imagine if the cams were not split intakes and a little bigger like my intakes :)

About the sniffer on the tailpipe if you have small exhaust leaks it will cause the tail pipe sniffer to show lean.

We do need to make sure all is good.

Glad to hear you are enjoying her.

Pete

[efnfast]

I'm loving it, the wife, not so much.
How do we make sure all is good.

[George Maz]

Steve, here's the info you requested.

Fully ported (heads/IH/plenum/63mm TB) by Greg VanDeventer (Ported and polished, back cut valves, machined exhaust guides for seals, milled cylinder head decks, polished cylinder head combustion chambers); RC injectors (205cc). South Georgia Corvette Stage 1 cams (lift .420, duration 230 degrees at .050 intake/exhaust). Rebuilt bottom half with stock take offs from 95 crate. Blueprint and balanced.
SW headers, Corsa exhaust, no cats
Haibeck custom dyno tune.

[XfireZ51]

When I talked to Pete about the 13.9, he custom tuned with a bung on the headers, the dyno guy used a sniffer in the end of the tail pipe. So there might be some discrepancy there.


I would trust Pete's WB. At least you know where his has been.

[Pete]

I would trust Pete's WB. At least you know where his has been.



Where mine has been. LMAO

Pete

[Pete]

I'm loving it, the wife, not so much.
How do we make sure all is good.

Steve,it's obvious your not getting detonation so it must be ok but just in case.
What we can do is sent me your graph we make corrections if it is lean then you have about another 10hp coming to you if not then you will loose some power and/or be sluggish.

Then put on a full 3" free flowing exhaust (Dynomax 17228 mufflers) and pick up another 10HP ;)

Pete