Hey all,

I was looking over the 5 free mods in the latest GM HTP. I wanted to ask a few questions about them. Who all has done them, and did they feel any gain? I am putting a lid on this week w/ the Holley Powershot, and was going to do that mod where you cut the plastic part out, ect.

What about that TB mod? Is there really a gain from that little bit of grinding? Also the debate over the screen. I left mine in my 95Z, b/c Ed W. and I went through a lot of dicussions over why the fuel trims would be better w/ a stock, unported MAF w/ screen. Did anyone have any problems removing the screen? Since it leaves the 3 sensors open to any damage?

I know I have a lot of questions, and I hope I can get some info

Thanks!

 

Havent read the article, what are the five free mods?

 

I removed the screen and ported the MAF this weekend. At the same time I did the free Ram air mod. I didn't have to cut the EGR tube since my '02 doesn't have it. The free ram air is definately worth the time. Very easy to do, and it looks like it'd make a HUGE difference in the airflow. The MAF is arguable. If you just pop the screen off then you still have two large fins that will provide some protection for the wires. Popping the screen is very easy. I cut out the fins and polished the ends, and then I cut out the extra supports for the MAF sensor wires. All the pics aer already on installuniversity.com. Seat of pants feel is very subjective, but it felt stronger to me. I already have the TB bypass, and will port the TB this week.

Have fun!

Ed

 

The mods in the magazine were:

Throttle Body Coolant bypass
chopping egr tube
free ram air
descreened MAF
ported Throttle Body

As for the worth, GMHTP did gain about 10HP, so there is something there. I've done 4 out of 5 of them, plus ground the throttle stop to fully open the throttle blades.

These mods are all pretty easy to do but if you have an auto DO NOT PORT THE MAF sensor (descreening is OK though). Porting the MAF does indeed soften the 4L60E's shifts I noticed a significant difference when I put the stock MAF ends back on in place of the ported ones.

 

What was the one you did not do? The TB has a "stop" on it? You mean the blades don't open fully??? I had no idea. I am new to LS1s. Most of my knowledge is on LT1s.

NEVER PORT the MAF. I don't care what people say. You would have to have over 800+hp for that to cause an obstruction. You can ask any tuner....Descreen, that is fine....been there, done that, back w/ the screen and stock MAF halves. And I am pushing
450+ at the crank on my LT1.

I would like to hear more people's experiences w/ these free mods. Is the TB coolant bypass messy at all?? Does any coolant need to be drained?

 

Any gain isn't going to come from removing an airflow restriction...it's going to come from adjusting the fuel curve and timing.

I had good results with a home ported MAF on my '98, but I'm too chicken to do that on my '02.

 

This should pretty much explain it: http://www.installuniversity.com/ins..._bump_stop.htm

 

It says you have to have an Autotap, ect. to perform it correctly?

It didn't say anything about that in GM HTP. I guess ya have to be careful and judge it accordingly.

Anyone here do that, and have any problems?

Thanks for the info

 

I think its funny that they say it like autotap is something everybody has. Who in the world has Autotap just laying around, its crazy expensive and all it does it give diagnostics.

The throttlebody coolant bypass wasn't messy at all. It took about 15 minutes tugging at the dumb tube pinching the things together.

I'd say that the these mods are pretty worthless I havent noticed any difference. I'm planning on getting headers and an electric cutout. Those should put up some real gains.

 

personally autotap has been worth it for me...figure a diagnostic check at any shop will run you about 50-75 bucks...i use it to datalog on all of my vehicles and has been a big help in alot of cases tracking down stupid stuff. The other day my buick threw a code turns out it was just the fuel cap was loose...i know it wouldve saved me that fee right there. And ls1 edit doesnt have diagnostics and thats twice as expensive so lets just take a blind guess of what amount of timing and fuel we need lol. Besides you can use it on any car like i said ive used it on probably 10-15 different cars helping myself and others figure things out and make sure nothing was wrong.

lata
Bill

 

Well, I don't think they are worthless if they were in GM HTP, and did show a NET gain of 10 rwhp. I can see the logic in them all.

Yeah, headers, cam, ect. are great mods, my Z is heavily modded, but doing some for FREE and getting a small gain is nice.

 

Don't forget 10 free RWHP is like 15-17 at the crank (depending on the formula you use!) Not too shabby for a few hours time!

Ed

 

That is what I was talking about I don't think they are worthless mods at all!

 

So far I've done... free ram air, TB coolant bypass, ported AND polished the MAF, and this weekend I plan to cut off the fins on the stock air lid. I have had no problems with throwing codes, pinging, improper timing, fuel too rich/lean, or any other problem. I don't have access to a dyno so no idea what gains I might have, and not a real SOTP difference either. But it's something to do and every little bit helps, right?

 

Descreening the MAF is not a good idea.

1. There's something that could always get past the filter and go in there

2. The screen also straightens out the airflow

I doubt you'll see any gain in doing it, so why do it?