More power, worth it?
More power, worth it? I am currently awaiting a new 9" for my car and was thinking of ways to recoup some lost power and possibly get it to hold on longer. I made 427/419 with whats in my sig but my torque falls off after 5700 rpm or so. After seeing another cars dyno with the same cam and light ported heads his did not drop off anything like mine. It has been discussed that 11/32'' pushrods may help me in that situation. so my thoughts are to get it to carry farther and recoup some of the lost power from the 9" I would add the following:
11/32" pushrods
FTP 104 mm lid and 100mm maf (Going from an unknown stock like lid and factory maf)
Light porting of the intake
Do you think this will do what I want? would it be worth it?
11/32" pushrods
FTP 104 mm lid and 100mm maf (Going from an unknown stock like lid and factory maf)
Light porting of the intake
Do you think this will do what I want? would it be worth it?
inssanity21, I really think the biggest difference in our setups are the lifters, pushrods and compression. The only work that was done to my heads was I hogged out the bowels (area under the valves), removed the rocker bolt bumps and finished the stock ports with 80 grit sanding rolls. The heads might help a little but I really think this cam likes the added compression.
The lid and maf will help, especially if the current ones are stock sized. So will porting the intake and that's free.
What you're really missing here is headflow. You got a healthy cam, good intake system (that's about to get better) but heads that only flow 250 at best.
What you're really missing here is headflow. You got a healthy cam, good intake system (that's about to get better) but heads that only flow 250 at best.
One day the heads will be ported, it is just not in the cards right now. I have thought about getting a thinner head gasket to bump the compression but I think I would rather do that when they get ported. It might just have to stay the way it is.
The fact that you car falls off at 5700 is more likely than not in the valvetrain. A stock 243 casting has plenty of cross sectional area to support well over 6500rpm in a 346 application. Have you measured pushrod length or did you just throw in a set of 7.4" pushrods?
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The fact that you car falls off at 5700 is more likely than not in the valvetrain. A stock 243 casting has plenty of cross sectional area to support well over 6500rpm in a 346 application. Have you measured pushrod length or did you just throw in a set of 7.4" pushrods?
I'm about to order that same cam and have my heads done but TEA said there might be a clearance issue on a stock short block. I have a nice set of 7.4" pushrods but wanted to know if I'd have to replace them.
Scott
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That was my question too. ??? Also, did you have P2V clearance issues with the 243 head and Tick SNS Stage III?
I'm about to order that same cam and have my heads done but TEA said there might be a clearance issue on a stock short block. I have a nice set of 7.4" pushrods but wanted to know if I'd have to replace them.
Scott
I'm about to order that same cam and have my heads done but TEA said there might be a clearance issue on a stock short block. I have a nice set of 7.4" pushrods but wanted to know if I'd have to replace them.
Scott
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Verdad Gallardo I don't have my exact p2v clearance measurements in front of me but they were plenty safe. If I recall correctly I could go another .015 and still be safe. Do not just use 7.4 pushrods. Measure! I ended up with 7.375 length.
Those mods are relatively cheap, so the gain from doing them will be good in regards to money spent vs. power gained. That is assuming you're doing the work yourself. If you have any additional funds, get those 243's ported. You'll pick up a bunch from that.
Between the lifters, push rods, added compression and whatever work was done to the heads on Poltergeist's car, is a whole lot of added variables compared to Insannity's car.
Not to mention the different tuners, different dyno's etc. Shape of the power curve aside, those two things can and will make a difference.
I do think the modifications Insannity mentioned though are good ones that will only help improve the performance of his car. Anything upstream of the 92mm TB that is smaller than that TB will be a restriction.
Might even think about doing something similar to this:
https://ls1tech.com/forums/generatio...l#post18329320
Not to mention the different tuners, different dyno's etc. Shape of the power curve aside, those two things can and will make a difference.
I do think the modifications Insannity mentioned though are good ones that will only help improve the performance of his car. Anything upstream of the 92mm TB that is smaller than that TB will be a restriction.
Might even think about doing something similar to this:
https://ls1tech.com/forums/generatio...l#post18329320
That stack looks pretty badass! I do understand that there are many variables between our cars I am just looking to recoup what the 9" will eat up and see if it will carry a little longer without taking heads off. I will however be porting the heads and intake first thing next season. I am going to just put this all on the back burner until the heads are done. Between ordering a mwc 9" and viking coilovers I am going to need some time to replenish the car fund.