loss of power???? installed new clutch and exhaust? - Page 3 - ZR-1 Net Registry Forums

ArcticZR1 · 03-26-2007

I'm getting worried now...I have my B&B w/ X pipe coming this week. Is it going to be bad hooking it straight up to a stock car for now? This will be the first mod my 91' has seen...

jonszr1 · 03-26-2007

if its like the flowmaster was ,it will be a piece of cake. you might want to call b&b and ask them for any hints or things they feel you might need to put their system on

cward · 03-26-2007

Interesting thread. I thought I would throw in my opinion. The first thing I did to #364 was headers thru stock exhaust, no cats. It gained hp and torque. Then put on ported plenum and IH. Gains in both. Then Power Effects mufflers thru stock resonators. A little gain. Then removed resonators and put in X-pipe. No gain in torque and may have lost a couple of lbs. Then changed plenum for one that was ported about as much as you can without cutting. Also custom 3" SS exhaust with X-pipe and nothing else. About as free flow as you can get. Torque stayed about the same or might have lost a couple of lbs. Rwhp went up about 20 hp. At that point, my torque was right around 350 lbs and rwhp about 392.

When you said it backfired a little, I would check vaccum lines etc. Should not backfire at all. And I would not worry about putting on B&B with X. More (a little) hp and probably same torque.

About roasting tires in 2 and 3 gears. That should not happen with stock or even lightly mod Z. Some spin in 2nd and maybe a squeek in 3rd but no roasting. If that happens, get better tires. :-) Even with 4.10 gears. In fact, even when I sprayed, and was probably putting out about 600 rwhp and close to that in torque, I would not roast 3rd. I could in 2nd but had to try, and that is not the goal so just a little technique and good tires made everything OK. I know of one person that went from 4.10 to 3.73 but that was for running standing mile. He ran out of gear before the end of the mile, over 180, not for street or strip driving.

Curtis

jonszr1 · 03-26-2007

opps hope ya all don't think I can roast my tires in second or third . with the 410s and goodyear d3-3s first gear is a joke. that is why I personally would like 373s . my left foot seem to have a mind of its own, it just for some reason gets excited and goes straight to the floor

.so i figured with 373s if figured I wouldn't have to try to retrain that 54yr old foot

zr-1assassin · 03-26-2007

Quote:

Originally Posted by ArcticZR1

I'm getting worried now...I have my B&B w/ X pipe coming this week. Is it going to be bad hooking it straight up to a stock car for now? This will be the first mod my 91' has seen...

i think you may lose a little low end, but who knows maybe it was just mine(my luck), even if it does you will get it back in the future im sure. let me know if it does.

ArcticZR1 · 03-26-2007

With my stock ZR1 I can get a pretty good bark in 2nd...but thats dropping it over 3k with the secondaries on...when those kick in cool sh$& happens! Quiet in 3rd though. I envy you guys who are up in the 400hp+ range...I just don't know how you keep tires on the car...I couldn't!

JMKZR1-94 · 04-24-2007

Hi Guy,s

First:
I was thinking of replacing rear-gear to 4.10 and found one at ECKLERS. The thing is that, first they told me that it has to be a Dana 46 or 48 but later i got a mail from them telling me that the rebuilt Dana 44 that they offer is working for my 94 Zr-1...??

Second:
Can You guy,s give me some hints of where to find nice rims and tires, maybe 18" or 19" with the right offset and so on.....

Looking forward to here from You
PS, The snow is just about to leave Sweden...=D>

cuisinartvette · 04-24-2007

I doubt you lost that much power from the exhaust. having mufflers that breathe and minimizing backpressure...good.
Too big a pipe diameter you lose velocity and scavenging..Not good, but wont make the car a total pig either. Did your 02 sensor get baged up during your exhaust change?
Any dyno nearby where you can have the A/F ratio checked via a sniffer in the pipe?

I have dual 3's on mine and it may be overkill..even if I got to keep it and do a top end port job Im betting 2.5 in pipes are fine. It may flow more air, but its still a small motor.

03-26-2007	#21
ArcticZR1 Join Date: Feb 2007 Location: Florida Posts: 82	Re: loss of power???? installed new clutch and exhaust? I'm getting worried now...I have my B&B w/ X pipe coming this week. Is it going to be bad hooking it straight up to a stock car for now? This will be the first mod my 91' has seen... __________________ ArcticZR1 91' White/Red #858

03-26-2007	#22
jonszr1 Join Date: Sep 2006 Location: lone pine and mammoth lakes Posts: 1,407	Re: loss of power???? installed new clutch and exhaust? if its like the flowmaster was ,it will be a piece of cake. you might want to call b&b and ask them for any hints or things they feel you might need to put their system on

03-26-2007	#23
cward Join Date: Dec 2004 Location: Luling, TX Posts: 97	Re: loss of power???? installed new clutch and exhaust? Interesting thread. I thought I would throw in my opinion. The first thing I did to #364 was headers thru stock exhaust, no cats. It gained hp and torque. Then put on ported plenum and IH. Gains in both. Then Power Effects mufflers thru stock resonators. A little gain. Then removed resonators and put in X-pipe. No gain in torque and may have lost a couple of lbs. Then changed plenum for one that was ported about as much as you can without cutting. Also custom 3" SS exhaust with X-pipe and nothing else. About as free flow as you can get. Torque stayed about the same or might have lost a couple of lbs. Rwhp went up about 20 hp. At that point, my torque was right around 350 lbs and rwhp about 392. When you said it backfired a little, I would check vaccum lines etc. Should not backfire at all. And I would not worry about putting on B&B with X. More (a little) hp and probably same torque. About roasting tires in 2 and 3 gears. That should not happen with stock or even lightly mod Z. Some spin in 2nd and maybe a squeek in 3rd but no roasting. If that happens, get better tires. :-) Even with 4.10 gears. In fact, even when I sprayed, and was probably putting out about 600 rwhp and close to that in torque, I would not roast 3rd. I could in 2nd but had to try, and that is not the goal so just a little technique and good tires made everything OK. I know of one person that went from 4.10 to 3.73 but that was for running standing mile. He ran out of gear before the end of the mile, over 180, not for street or strip driving. Curtis __________________ Curtis Ward 91 ZR-1 #364 RIP

03-26-2007	#24
jonszr1 Join Date: Sep 2006 Location: lone pine and mammoth lakes Posts: 1,407	Re: loss of power???? installed new clutch and exhaust? opps hope ya all don't think I can roast my tires in second or third . with the 410s and goodyear d3-3s first gear is a joke. that is why I personally would like 373s . my left foot seem to have a mind of its own, it just for some reason gets excited and goes straight to the floor .so i figured with 373s if figured I wouldn't have to try to retrain that 54yr old foot

03-26-2007	#26
ArcticZR1 Join Date: Feb 2007 Location: Florida Posts: 82	Re: loss of power???? installed new clutch and exhaust? With my stock ZR1 I can get a pretty good bark in 2nd...but thats dropping it over 3k with the secondaries on...when those kick in cool sh$& happens! Quiet in 3rd though. I envy you guys who are up in the 400hp+ range...I just don't know how you keep tires on the car...I couldn't! __________________ ArcticZR1 91' White/Red #858

04-24-2007	#27
JMKZR1-94 Join Date: Feb 2007 Location: SWEDEN Posts: 5	Re: loss of power???? installed new clutch and exhaust? Hi Guy,s First: I was thinking of replacing rear-gear to 4.10 and found one at ECKLERS. The thing is that, first they told me that it has to be a Dana 46 or 48 but later i got a mail from them telling me that the rebuilt Dana 44 that they offer is working for my 94 Zr-1...?? Second: Can You guy,s give me some hints of where to find nice rims and tires, maybe 18" or 19" with the right offset and so on..... Looking forward to here from You PS, The snow is just about to leave Sweden...=D>

04-24-2007	#28
cuisinartvette Join Date: Aug 2005 Location: San Fernando Valley, CA. Posts: 896	Re: loss of power???? installed new clutch and exhaust? I doubt you lost that much power from the exhaust. having mufflers that breathe and minimizing backpressure...good. Too big a pipe diameter you lose velocity and scavenging..Not good, but wont make the car a total pig either. Did your 02 sensor get baged up during your exhaust change? Any dyno nearby where you can have the A/F ratio checked via a sniffer in the pipe? I have dual 3's on mine and it may be overkill..even if I got to keep it and do a top end port job Im betting 2.5 in pipes are fine. It may flow more air, but its still a small motor. __________________ 1990 ZR1, 142,000 miles-Black on black 4.09's Haibeck chip, 3"exh, K&N, meth inj.