[s346k]

i had the fleeting thought that i could use the timer in hpt logs to compare wot pulls and subsequently, performance. this is proving to be a giant pain in the ass. going through log data for this purpose is very time consuming. especially when splitting hairs. i'm going to see how consistent a dragy is, it should be easier to use and compare.

[cmitchell17]

Originally Posted by s346k

i had the fleeting thought that i could use the timer in hpt logs to compare wot pulls and subsequently, performance. this is proving to be a giant pain in the ass. going through log data for this purpose is very time consuming. especially when splitting hairs. i'm going to see how consistent a dragy is, it should be easier to use and compare.

I have a draggy too, I think it works ok. I am not a believer in track times are the best way to gauge performance either though. You have just introduced a huge variable and that's traction.

[s346k]

Originally Posted by cmitchell17

I have a draggy too, I think it works ok. I am not a believer in track times are the best way to gauge performance either though. You have just introduced a huge variable and that's traction.

yeah. i'm installing an LT2 intake manifold this weekend. it has the stock LT1 on it now. i presume the kpa will drop a touch more since the new manifold is capable of moving more air and the current setup is already showing a restriction. in theory it should put more vacuum on whatever is holding it back now. we shall see.

the track is great if you have a private rental. otherwise... it's not so good.

[6spdhyperblue]

A setup that dead hooks is helpful for measuring performance. If you do it enough you can factor in wind and a little slip.

About time..get that LT2 on there.

[cmitchell17]

Originally Posted by s346k

yeah. i'm installing an LT2 intake manifold this weekend. it has the stock LT1 on it now. i presume the kpa will drop a touch more since the new manifold is capable of moving more air and the current setup is already showing a restriction. in theory it should put more vacuum on whatever is holding it back now. we shall see.

the track is great if you have a private rental. otherwise... it's not so good.

Where did you get it from?

[s346k]

Originally Posted by cmitchell17

Where did you get it from?

i got it about 3 weeks ago thru a friend. i also got antsy and installed it this morning after work.

ill get some logs this weekend. i will say the car did not like it, first few miles it was very lethargic. seemed to be coming out of it after 25 miles but still not like it was. against my better judgement, i'll drive it to work tonight.

and yes, i'll beat you to the punch. there is a lot of ashy larry stuff going on under the hood.

[s346k]

i think the car needed some time to get acclimated. i drove it around this morning and did some wot 3rd gear stuff. made 7 pulls, all were consistent. as suspected, the kpa is now down to 94.0 at the lowest point, from 96. maf says it's moving more air, almost 52lb now. kpa starts dropping as early as 3k rpm. drives and responds like stock again, roughly 50 miles of driving.

im guessing the tb is the pinch, as it appears the rotofab will hold its own above this power level. car has full exhaust, stock lt2 manifold, stock lt1 tb, rotofab, ethanol. sensor says 79% now.

[6spdhyperblue]

Off idle low end torque feels similar to the lt1 intake?

Which manifold bolts did you use?

[s346k]

tbh the car feels the exact same did it with the stock lt1 intake on it. my butt dyno hasn't been calibrated recently, so there's that. according to the numbers it is definitely moving more air, but that's all i can tell you. i was expecting to notice 5500+ but perhaps i was more interested in watching traffic. the car is loud inside at wot and it's hard to concentrate on much of anything @ 6000 rpm.

[cmitchell17]

Originally Posted by s346k

tbh the car feels the exact same did it with the stock lt1 intake on it. my butt dyno hasn't been calibrated recently, so there's that. according to the numbers it is definitely moving more air, but that's all i can tell you. i was expecting to notice 5500+ but perhaps i was more interested in watching traffic. the car is loud inside at wot and it's hard to concentrate on much of anything @ 6000 rpm.

Thanks for the info, most people are way too influenced by the placebo effect. In my opinion the butt dyno has a instrument limit of error of probably about 75-100 HP, that means the butt dyno cannot properly detect any HP increases below about 75HP and is extremely imprecise.

Anyway, it seems like to me from the logs you took you are reporting a 2kPa change in manifold pressure and 52lb/hr increase in MAF? That is a significant increase in MAF flow.

[s346k]

made some pulls with a car i've ran before. the manifold definitely helped. appears to have picked up 1.5 maybe 2 mph. im very happy with it. i think using a 95 mm tb is the ticket to optimization. i think it would mitigate the kpa loss. i'm using a rock stock lt1 tb, i almost wish i had modified the intake to accept the 95.

lt2 im + lt5 tb is going to be the best bang for the buck, hands down.

the logs showed 48.5ish lb/min with the stock lt1 intake last week. lt2 showed 51.8 almost 52 today. i'm curious to see what the msd/95 combo does in comparison. still waiting on the msd to show up.

[6spdhyperblue]

Like to hear anymore thoughts on the manifold If you had any

[s346k]

Originally Posted by 6spdhyperblue

Like to hear anymore thoughts on the manifold If you had any

i think its a great budget setup. i would expect it to rival msd numbers until a bigger camshaft comes into play. it's hard to say where they are going from here pricewise. ive seen places offering them ready to bolt on at almost 3x the cost from gm. seems a bit excessive when all it takes to make one work is about 30 minutes and a small fitting.

once over $500, i would not consider it. i don't see porting doing much for the intake runners, i think the gains over stock will be from using a bigger tb. even an msd is going to be better in stock trim at all power levels, and out of the box gives you the ability to use a big tb. the gap will only widen as more power is made.

[cmitchell17]

Originally Posted by s346k

i think its a great budget setup. i would expect it to rival msd numbers until a bigger camshaft comes into play. it's hard to say where they are going from here pricewise. ive seen places offering them ready to bolt on at almost 3x the cost from gm. seems a bit excessive when all it takes to make one work is about 30 minutes and a small fitting.

once over $500, i would not consider it. i don't see porting doing much for the intake runners, i think the gains over stock will be from using a bigger tb. even an msd is going to be better in stock trim at all power levels, and out of the box gives you the ability to use a big tb. the gap will only widen as more power is made.

Why did you buy both a LT2 and a MSD?