people with Apten & 2.80 pulley

[D-Cobra]

going in to retune my car tomorrow and i need some imputs from those of you (preferrebly in Florida) whose car is running strong. what's the optimal on the following:

how many degrees of timing are you running on your car?

what's your A/F ratio?

where's your car's redline set?

what numbers did your car put down at the dyno?

and whatever you think is relevant in terms of tunning.

 

[drkchk03svt]

I know this is a little off subject but.... I am getting ready to order the apten and I have a 2.8. Have you ever considered adding a 2 or 4lb lower to your setup?

 

[D-Cobra]

Originally posted by drkchk03svt
I know this is a little off subject but.... I am getting ready to order the apten and I have a 2.8. Have you ever considered adding a 2 or 4lb lower to your setup?

actually no. because i hear many people explaining a 2.80 or 2.76 pulley is already kind of maxing out the eaton's capability. a lower pulley will just over spin the eaton and create nothing more but unwanted heat for the motor. hope this helps.

 

[drkchk03svt]

Originally posted by D-Cobra
actually no. because i hear many people explaining a 2.80 or 2.76 pulley is already kind of maxing out the eaton's capability. a lower pulley will just over spin the eaton and create nothing more but unwanted heat for the motor. hope this helps.

But with the apten your blower is more heat efficiant.

 

[Hissssnsvt]

Good point, i would think a lower pulley set-up would get you some added torque back that you lose with the ported blower. IMO, an upgrade in heat exchanger would be a must with any upper and lower pulley swap.

Bump for the original topic.

 

[CobraBob]

It is much better to combine an upper and lower than to go with the smallest upper. Have you considered a 2.93 and a 4 lb. lower? You will see good power and more torque with that combo. Just a thought.

I used a 2.80 (no lower) but to be honest I liked my 2.90 much better.

While it is true that porting the blower makes it more efficient, remember that you are still spinning it beyond what it was intended. You will still overspin it and generate more heat as you add smaller uppers.

And most definitely 'Yes' on a HE. A much recommended mod with any pullied motor or ported blower. It's not even a bad idea on a stock motor. LOL!

 

[D-Cobra]

ok people, stop hi-jacking my thread, and start answering my question.

 

[broke7]

Im on my way to Florida, the same tuning rules should apply wherever you are at.

A good street tune for someone who generally makes 490-500whp on an apten 2.80 upper setup will usually run run anywhere from a 11.5-12.5 a/f ratio. I have ran mine at 12.5 and sometimes higher for about 14k miles with no problems. I recently just got a wideband and have added some fuel to my tune via predator and im happy with the performance.

In the timing department most seem to be using anywhere from 21.5 degrees to the higher 23's degrees to get some good #'s. Your dynotuner will do whats best for you. Some cars like timing #'s, others dont. There has been a on-going argument that high timing advance #'s wont get you extra power. Then you look at trey193 and some others who make huge #'s and his cars makes 518SAE and has been 11.1 @ 126 with an 2.80 and NO lower. In mid 80 degree heat. He has 26 degrees in his tune, but this would be considered a race tune and he runs a pump gas/100 octane mix.

I have ran several tune all in the low 12:1 a/f ratio and they all make right at the 500 mark on my car.

I like a 7000rpm rev limiter, that way if your powershifting and the rpm does jump up a tad it wont kill your run, because the car will bog if it meets the rev limiter and pretty much ruin a run down the track.

 

[CobraBob]

Originally posted by D-Cobra
ok people, stop hi-jacking my thread, and start answering my question.

Opps! Sorry about that. :uh oh:

 

[Sport The War]

so would you say the apten hurts the car in the performance dept? or is it better to just stick with the stock blower and get a heat exchanger with a 2.90?? i need alittle insight im going to be putting together a cobra in a month or so here.

 

[drkchk03svt]

Originally posted by Sport The War
so would you say the apten hurts the car in the performance dept? or is it better to just stick with the stock blower and get a heat exchanger with a 2.90?? i need alittle insight im going to be putting together a cobra in a month or so here.

open a new thread!

 

[CobraBob]

Originally posted by drkchk03svt
open a new thread!

:lol:

 

[Quick Strike]

Originally posted by D-Cobra

how many degrees of timing are you running on your car?

what's your A/F ratio?

where's your car's redline set?

what numbers did your car put down at the dyno?

and whatever you think is relevant in terms of tunning.

My car has CAI, a Steeda catback, 2.80 pully, Apten porting, an Afco HE and a custom SCT dyno reflash. In answer to your questions (the first to actually do so):

It runs 22* timing.

A/F is a flat 11.8 across the curve

Redline is 6500, but I shift at 6000. 6500 is not to be exceeded as the MAF is pegged there.

It dynoed at 477 SAE RWHP and 477 SAE RWTQ in the heat with a slipping clutch. It had an earlier dyno with a good clutch but rich airflow (10 and below) at 463 RWHP and 485 RWTQ. I think it could make 500/500 with a good clutch in cool crisp air.

I was one of the last buyers from Apten under Brian H. He also did the second EEC reflash on the Dyno. He liked the 2.80 with the ported Eaton. The greater efficiency through porting offset some of the heat of overspinning. The HE was marginal in my application, but I thought it might last longer with less heat.

 

[FINICKY]

numbers in sig ....12.0 air fuel. 23 degrees timing. Thats a 2.80 upper no lower. Runs great and picked up 4 tenths over a 2.93 and a stock blower. Also picked up 4 MPH.