View Poll Results: What cam to run with ported 799 heads?
Keep current cam, just get the heads on and save $$$
5
29.41%
Look for a used cam to buy trade for almost zero $$$ loss
0
0%
Order custom EPS cam, sell old cam/heads, and some out of pocket $$$
12
70.59%
Voters: 17. You may not vote on this poll
Keep cam or upgrade with ported/milled 243/799 heads?
#61
Well to be clear I am looking at swapping heads AND cam.
To the guy who said rod bolts and spin it higher, my HP peaks at under 6000rpm and I'm shifting at 6300 as is, tried spinning higher and MPH didn't increase.
My last track slip:
DA 1842, race weight within 50lbs of 3700#
60 ft: 1.7776 (approx half throttle for a few feet out then stabbed it, track wouldn't hold WOT launch even on 325/50r15 MT ET streets)
330ft: 5.0621
1/8th: 7.8091
trap: 89.55
1000: 10.2091
trap: 101.81
1/4: 12.2473
trap:110.38
On the dyno it made a measily 345rwhp/325rwtq unlocked, exhaust capped. I will post the dyno sheet Monday, I can scan it at work.
I am happy with the converter since I do daily drive the car. I want more power in general because the car doesn't perform as well as I would like from a roll. Only able to put a car and a half on a stock EVO X on the highway.
I have looked over my engine up and down for reasons why it would make such little power and found nothing, posted several times here on tech with no new ideas.
To the guy who said rod bolts and spin it higher, my HP peaks at under 6000rpm and I'm shifting at 6300 as is, tried spinning higher and MPH didn't increase.
My last track slip:
DA 1842, race weight within 50lbs of 3700#
60 ft: 1.7776 (approx half throttle for a few feet out then stabbed it, track wouldn't hold WOT launch even on 325/50r15 MT ET streets)
330ft: 5.0621
1/8th: 7.8091
trap: 89.55
1000: 10.2091
trap: 101.81
1/4: 12.2473
trap:110.38
On the dyno it made a measily 345rwhp/325rwtq unlocked, exhaust capped. I will post the dyno sheet Monday, I can scan it at work.
I am happy with the converter since I do daily drive the car. I want more power in general because the car doesn't perform as well as I would like from a roll. Only able to put a car and a half on a stock EVO X on the highway.
I have looked over my engine up and down for reasons why it would make such little power and found nothing, posted several times here on tech with no new ideas.
A4s with high stall converters generally don't show impressive dyno numbers,especially unlocked.don't worry about dyno numbers,it's what you run at the track that counts.
#62
60 ft: 1.7776 (approx half throttle for a few feet out then stabbed it, track wouldn't hold WOT launch even on 325/50r15 MT ET streets)
330ft: 5.0621
1/8th: 7.8091
trap: 89.55
1000: 10.2091
trap: 101.81
1/4: 12.2473
trap:110.38
On the dyno it made a measily 345rwhp/325rwtq unlocked, exhaust capped. I will post the dyno sheet Monday, I can scan it at work.
330ft: 5.0621
1/8th: 7.8091
trap: 89.55
1000: 10.2091
trap: 101.81
1/4: 12.2473
trap:110.38
On the dyno it made a measily 345rwhp/325rwtq unlocked, exhaust capped. I will post the dyno sheet Monday, I can scan it at work.
http://www.hotrodpitstop.com/tools.html
According to the drag race calculator, 110.38 MPH in the quarter @ 3700 lbs is equal to 388.35 horsepower. If you car weights 3750, that put's you at 393 HP. Those is pretty common numbers posted on LS1Tech.com for a cam only LS1 with your size cam.
#63
Here you go:
When you have a really good exhaust and are somewhat intake restricted, reverse splits make a lot of sense. A perfect example is when you're running stock heads with LS6 intake and long tube headers with off-road exhaust. A single pattern cam or reverse split cam works great there.
Last edited by MM98; 03-17-2011 at 09:25 AM.
#66
i would be pretty happy with your numbers as is right now.damn respectable for just a cam only with 853s..
don't overthink this.you can add those heads,(and cam )for not a lot of money and be in the 11s!
#67
You know, I really don't know if it is supposed to be one or the other or something in between. My experience tells me it is something in between.
#68
Here is a dyno sheet of a cam only reverse split with a fast intake. As you can see it still made power. This along with RMTT reverse split with fast intakes show you reverse splits do still make power with a ported fast. Cant believe everything people say on this site.
https://ls1tech.com/forums/dynamomet...-2005-gto.html
#69
Here is the calculator formula we always used back in the day:
HP = ((MPH / 234)^3) * Weight
So, for you car it would be
HP = ((110.5/234)^3) * 3700
HP = ((.4722222)^3) * 3700
HP = (.105302) * 3700
HP = 389.61
HP = ((MPH / 234)^3) * Weight
So, for you car it would be
HP = ((110.5/234)^3) * 3700
HP = ((.4722222)^3) * 3700
HP = (.105302) * 3700
HP = 389.61
#70
#71
Originally Posted by MM98
This is great advice too! Also, if I remember correctly, the old reverse split cams where ment for the use of an LS6 intake & stock heads.. You're stepping up to ported heads & already have a Fast 90.. Why not get a better cam spec'd for this set-up?
This is great advice too! Also, if I remember correctly, the old reverse split cams where ment for the use of an LS6 intake & stock heads.. You're stepping up to ported heads & already have a Fast 90.. Why not get a better cam spec'd for this set-up?
That doesn't mean it is designed for LS6 intake & stock heads, it is not really designed for high rpms, though if properly specked, it will carry beyond 6600 easy. All within {certain} parameters.
It responds well to intake, head mods within its power range.
See same cam before heads/intake
#72
Thats true in most cases. There is some power to be had but when comparing cams of similar specs, there wont honestly be that much difference.
Here's a Cam Motion in action:
(dont bash me for the music it aint my video)
http://www.youtube.com/watch?v=9Fssw7rCyos
Here's a Cam Motion in action:
(dont bash me for the music it aint my video)
http://www.youtube.com/watch?v=9Fssw7rCyos
#74
in the OP's case,a cam with higher lift would take advantage of the increased airflow of the 799 heads compared to the 853s,even if the duration/overlap was the same as before.if he was keeping the same heads,the gains wouldn't be as much.it's all about the combo.
i think you could realistically see around a 50 hp gain with the swap,as long as the cam is properly matched to the heads.
#75
I have asked this question to a sponsor and i would need to up it to like a Tsunami 235 size cam for example to see any gains. But then my 3200 stall that i have will be too small.
His car might perform worse with a bigger cam and a small stall that doesnt match up to his cam? So get the bigger stall, and get the heads done right. Then if your not happy then go with a bigger cam, as you will have the stall size to match it and already have great heads to go with the bigger cam.
#76
I would not go for a bigger converter in his situation. 12.20 is really very good for 110 MPH. While a 1.5 or 1.6 60 foot time is great at the track, it isnt going to happen on the street. For street guys, once you get to a certain level in your 60 foot you just can't hook that up on the street with a drag radial. If he wants to be able to take out the new Camaros and Mustangs and be a street contender, He could use about 40 to 50 more horsepower.
#77
#78
Thread Starter
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From: Northwest AR
The car is setup to handle in corners, I don't get a ton of weight transfer so it's already a struggle to hook.
I can drive it well enough on drag radials to get the job done, but as I said even at the track so far I haven't ever hooked a straight WOT stab off the line. A larger/looser converter is going to make traction worse, drivability worse, and likely further kill off top end power.
I have some other things coming up so I think I'm going to focus on getting the heads ported and put on and see how everything goes. Predator Z also suggested maybe just retarding my cam a couple degrees.
Then when I do the new engine build I can get ARP rod bolts and everything else to spin 7k rpm and get a cam matched to my car to do that. Not necessarily much bigger, just broaden the power band.
I appreciate all the advice. I will be sure to post up results. I have already picked up some ARP head bolts and just paid a member for some Patriot Gold duals. I also already have a brand new set of Felpro head gaskets.
Should I use the dual springs on the 799s or save them for later and just put my PAC beehives on?
I can drive it well enough on drag radials to get the job done, but as I said even at the track so far I haven't ever hooked a straight WOT stab off the line. A larger/looser converter is going to make traction worse, drivability worse, and likely further kill off top end power.
I have some other things coming up so I think I'm going to focus on getting the heads ported and put on and see how everything goes. Predator Z also suggested maybe just retarding my cam a couple degrees.
Then when I do the new engine build I can get ARP rod bolts and everything else to spin 7k rpm and get a cam matched to my car to do that. Not necessarily much bigger, just broaden the power band.
I appreciate all the advice. I will be sure to post up results. I have already picked up some ARP head bolts and just paid a member for some Patriot Gold duals. I also already have a brand new set of Felpro head gaskets.
Should I use the dual springs on the 799s or save them for later and just put my PAC beehives on?