Looking for Bolt-on #'s (preferably with RR's and springs)
12-01-2011, 11:05 PM
#21
Read my earlier post....I already gave you these #'s bolt on for bolt on....you will not find the article on the internet....the LT1 bolt on dyno test it was WAY back in 1997 I believe when "GMHTP" was just "High Tech Performance" (they still featured Mustangs back then 
) As previously mentioned, 1.6 rockers and springs were worth 15 peak HP and as much as 20 HP at certain RPMs on a dynojet....I got the magazine still in my bathroom LOL. They have been proven again and again to give .02 gains in the 1/4.
) As previously mentioned, 1.6 rockers and springs were worth 15 peak HP and as much as 20 HP at certain RPMs on a dynojet....I got the magazine still in my bathroom LOL. They have been proven again and again to give .02 gains in the 1/4.
12-02-2011, 07:08 AM
#23
Also FWIW a good friend of mine had edelbrock shorties and a mufflex exhaust and when he switched to flp longtubes and the same mufflex he picked up under 5 hp and 5 trq. Same dyno and no other changes and the track backed it up.
12-02-2011, 07:49 AM
#24
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I have seen BBC engines dyno 10-20 hp more with a flowmaster race muffler and a Norma race muffler vs open headers. So im sure it would be the same with a SBC and the correct muffler.
12-02-2011, 10:33 AM
#25
There are other factors like tune and restriction in intake or exhaust. Realistically, mufflers aren't adding horsepower. And shorties typically yield significantly less power gains than long tubes because the assumption is that the cat(s) is(are) left in place... why else would you buy shorties when LT's are about the same price...
I... you sure your car doesn't have a mild cam or something? Those are some wicked numbers.
Mine put down 335 hp and 350 trq at the wheels. That was with basically all the bolt ons. That was also with slp shorty headers and true duals.
I think I picked up around 15 or so hp with the rockers. I didn't do springs at the time. i didn't dyno it but I was seeing a constant 2 mph increase at the track.
I think I picked up around 15 or so hp with the rockers. I didn't do springs at the time. i didn't dyno it but I was seeing a constant 2 mph increase at the track.
12-02-2011, 11:16 AM
#26
Stock cam. I got the car when it was 2 years old and had 11,000 miles on it. It was 100% stock. When I tore into the engine we pulled the cam and it was the stocker. We spent alot of time tuning it aswell.
The reason I did shorties at the time was the price I got them for and I had to keep the cats at the time. Soon after I learned how to get around the sniffer test
At the bolt on level I doubt you will see much difference in shorties vr. longtubes but as you get into cams, power adders and more cubes then you will start seeing the differences. I just know first hand on my buddies car. Everyone else I see going shorties to long tubes also change the entire exhaust so the gains are also from that.
The reason I did shorties at the time was the price I got them for and I had to keep the cats at the time. Soon after I learned how to get around the sniffer test
At the bolt on level I doubt you will see much difference in shorties vr. longtubes but as you get into cams, power adders and more cubes then you will start seeing the differences. I just know first hand on my buddies car. Everyone else I see going shorties to long tubes also change the entire exhaust so the gains are also from that.
12-02-2011, 02:22 PM
#27
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1994 Z28 M6
10 years ago ran a best of 13.05@105. 1.7 60ft. Dynoed 286HP at the wheels. I always felt there was a 12.9x in it somewhere.
Mods: TB coolant bypass, TB airfoil, K&N CAI, LT4 KM, 1.6RR's, Edelbrock shorties, MSD 6a, Random Technologies Cat, Flowmaster single 3inch in and out, 4:10 gears, SS rims with drag radials.
10 years ago ran a best of 13.05@105. 1.7 60ft. Dynoed 286HP at the wheels. I always felt there was a 12.9x in it somewhere.
Mods: TB coolant bypass, TB airfoil, K&N CAI, LT4 KM, 1.6RR's, Edelbrock shorties, MSD 6a, Random Technologies Cat, Flowmaster single 3inch in and out, 4:10 gears, SS rims with drag radials.
12-02-2011, 02:40 PM
#28
Nope...just re-read it last night...it was actually a High Performance Pontiac mag from 1997. They dynoed each part after installation and the "JBA shorties" (don't make them anymore) did make 15 more peak hp....keep in mind how restrictive the stock Y-pipe is...it's kinked as hell and small diameter pipe. The factory introduced a less restrictive larger diameter mandrel bent Y pipe in 1996 which was the cause for the bump from 275 to 285 HP; so there are bigger gains to be had on earlier LT1 cars. I used to have just a borla Y-pipe with manifolds and there was an immediate power gain. I'm sure longtubes could be worth 20-30 HP.
12-02-2011, 04:41 PM
#29
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Nope...just re-read it last night...it was actually a High Performance Pontiac mag from 1997. They dynoed each part after installation and the "JBA shorties" (don't make them anymore) did make 15 more peak hp....keep in mind how restrictive the stock Y-pipe is...it's kinked as hell and small diameter pipe. The factory introduced a less restrictive larger diameter mandrel bent Y pipe in 1996 which was the cause for the bump from 275 to 285 HP; so there are bigger gains to be had on earlier LT1 cars. I used to have just a borla Y-pipe with manifolds and there was an immediate power gain. I'm sure longtubes could be worth 20-30 HP.
