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Discussion Starter #1
does anyone know the stock 1/4 mile speed on the 91 caprice 350 with 3.42 rear gears 700r4 tranny the police package???????????
 
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Discussion Starter #2
A friend of mine's did 16.4 @ 83.

My dear discarded 305 did a 18.6 @ 72.
 
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cool kind discouraging though i added cam chip thermostat headers dual exuast no cats
1.6 roller rockers k&n filter deleted air pump redline 700r4 cherps the hell out 2nd
battery in trunk electric fans think i could break into 14's ?????
 
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Discussion Starter #6
<BLOCKQUOTE>quote:</font><HR>Originally posted by willcaprice:
cool kind discouraging though i added cam chip thermostat headers dual exuast no cats
1.6 roller rockers k&n filter deleted air pump redline 700r4 cherps the hell out 2nd
battery in trunk electric fans think i could break into 14's ?????
<HR></BLOCKQUOTE>

You did all the right things, BUT...

1. what cam?

and most importantly of all,

2. what chip?

I have several thoughts. First, the chip is probably not well-adapted to the mods you made, so some tuning is really needed to wek up the engine.

Second, you didn't say what you've run at the track, nor what the full timeslip data was. You need to post that here.

Third -- you did a lot of mods (good choices!) but you didn't mention replacing the old tired fuel pump to a new one capable of supplying enough fuel to feed the engine. You also didn't mention changing the fuel filter.

Bascially, a stock 91-93 Caprice with the 9C1 350 can run mid to low 16s in the quarter mile. Slightly modified on the exhaust and revising the air filter, as has been done by several list members, you can run 15.5 to 15.8 sec.

You, on the other hand, changed just about everything.... so that suggests (to me) that you should probably be running 15.0 sec or better. So it would help us (or me) if you would provide the details of

1. what cam
2. what chip
3. full timeslip data + weather consitions when you ran

Lastly and IMO, you need to add a cold air intake; using a K&N in the stock filter housing is not really an improvement. This will help, but it's really not going to fix your problem. I think the biggest problem you have is with the chip and possibly with not enough fuel getting to the engine.

HTH.
 
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Discussion Starter #7
thats cause i aint ran it at the track and the chip is the thrmomaster chip from hypertech the cam is crane powermax cam
crn-104211 thats duratation I:194 E:204
cam lift I:407 and E:429 witch brought me to somthing like 428 and 458 at the valve
 
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Discussion Starter #8
IMHO, the biggest limiting factor on our engines is the fact we have only 2 65# injectors. They are going to deliver a maximum qty of fuel, regardless of how much air will go through the engine.

The stock L05 heads are not known for flowing well, but if you've already maxed out fuel flow a change won't do you any good.

My best ever is a 15.50 @ 87.xx. I've gone side-by-side with SS's and I can get a jump at the start, but I have to just watch them pass at the end of the track. Yea, it's definitely frustrating. I'm experimenting with the vacuum assisted regulator and a BB throttle body and injectors.

Now if I can only get some help making a chip to get it all working together. :D
 
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Discussion Starter #9
oh ya and yes it a new fuel pump but stock and filter gets changed way more than need 3 times in two years
 
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Discussion Starter #10
<BLOCKQUOTE>quote:</font><HR>Originally posted by willcaprice:
... the chip is the Thermomaster chip from Hypertech the cam is Crane Powermax cam
crn-104211 thats durattion I:194 E:204
cam lift I:407 and E:429 which brought me to something like 428 and 458 at the valve
<HR></BLOCKQUOTE>

Ok that's helpful information.

The cam is better than a factory 94-96 Bcar cam, but not quite as good as an L98 cam... but it's still good enough.

Here's the problem. The cam is good enough to pump out 270+ hp if it were installed in a otherwise stock 94-96 Bcar LT1 engine (which has superb heads). You don't have those heads but you do have headers + duals, so your exhaust breathing is very good and probably better than the 94-96 LT1 has. So the 260-270 hp range is completely reasonable with that cam in your car.

But you aren't making that kind of power because the engine control (via the chip) and the fuel delivery are not enough to get close to those numbers.

OK taking the chip first: I don't think Hypertech does very much in that chip because it's a "one size, fits all" chip that, if I recall right, is really only going to alter the spark advance table and it will require you to use premium fuel. The chip might work well in a stock car -- but in your car, I think it will only make it run worse than the stock chip because the spark advance they use, plus the fact that your are probably running very lean, is a recipie for disaster.

Your mods to the engine, on the other hand, have greatly increased the engine breathing... so that means you need a lot more fuel to (a) prevent going lean and pinging, and (b) to actually make a lot more power than stock.

My suggestions:

1. Remove the Hypertech chip, and replace it with the stock one. If it runs better, then sell the Hypertech chip on EBay.

2. I assume you have a 9C1 Caprice, so that means you have the large 65 lb/hour injectors. That's good but it's not really enough. I don't think they will be able to supply enough fuel at wide-open-throttle, and they'll limit the engine around 230 hp if I remember right. So that leads to item 2.

3. Read about the so-called "quarter mod" on the http://www.thirdgen.org web site. You need to raise the fuel pressure in the fuel pressure regulator (FPR); this will *help* but it won't solve all your problems. You may eventually need larger injectors and/or the vFPR (vacuum-compensated FPR).

4. You may very well need to replace the fuel pump with one from a 94-96 LT1 Caprice. I don't know if the stock 91 pump can supply enough fuel to satisfy the engine. The LT1 Caprice fuel pump can pump enough to feed nearly 400 hp, so it would be fine for your engine, and it should be a bolt in. You could also use an aftermarket one like a Walbro.

5. this is the biggie --- I really think you won't ever get that engine running extremely well unless you can get someone to make you a custom chip. The items above are band aids -- they'll help, but I don't expect that they'll lead you to best case. The Hypertech chip is not suggested by any TBI people on the ThirdGen website (for the reasons I already said), and likewise I don't think it's a very good match for your car. If you had done almost no mods to the car, it might work fine. But with everything you've done, it's probably not any better than the stock chip. It might also be A LOT WORSE. In my opinion...

Dunno if this will be helpful to you or not.

The only other suggestion I could make is for you to find a 3rd Gen Fcar owner in your area who has done their own TBI chip burning; maybe they can log some data in your car and try making a chip for you.

In the meantime, try the above items. HTH.
 
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Discussion Starter #11
ok where would i get a custom chip and how much would it run me and my fpr is in the throotle body i dont know that it is adjustable and your information is very helpfull thanks do you know about a rev limiter does my car have one?
 
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Discussion Starter #12
Yes, there is a rev limiter. It's set at redline on the tach, 5000 rpm. That won't be your problem in making power and speed.

Don't buy a custom chip unless it's cheaply priced and the chip is made from data recorded from your car. You can learn how to record the data from information at the Thirdgen.org site. Check TBIchips.com or something like that for a chip. He'll need data but he is reasonably priced and seems to be very qualified.
 
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Discussion Starter #13
<BLOCKQUOTE>quote:</font><HR>Originally posted by willcaprice:
ok where would i get a custom chip and how much would it run me and my fpr is in the throotle body i dont know that it is adjustable and your information is very helpfull thanks do you know about a rev limiter does my car have one?<HR></BLOCKQUOTE>

Per PaulD suggestion:
http://www.tbichips.com/

Your FPR in the TBI is not adjustable from the factory -- that's why you need to modify it.

PaulD is right about the rev limiter; going above 5000 rpm won't solve any problems, and until you get the air:fuel mixture right (by altering the fuel pressure, and using a custom chip), going up above 5000 rpm is risky.... especially with the Hypertech chip and stock fuel pressure.

If this is all new to you (and it seems to be very new) -- that's fine. Everybody starts somewhere. With that said, you need to do a lot of reading on this forum, and probably on the ThirdGen website under the TBI forum,
http://www.thirdgen.org/techbb2/forumdisplay.php?s=&forumid=17

Learning all you can will help you get your engine running right. If you don't learn, you'll blow more money on parts, you won't be happy with the results, and you'll get tired of asking questions, nevermind that people may stop answering them.

Not flaming you, just some advice.

And lastly, you may be a long way from a track, so it may be hard for you to get a handle on exactly how bad, or good, the engine is running especially after you change more things. A laptop + WinALDL would help (there are links to it on the ThirdGen website) because you can log the vehicle speed sensor (VSS) along with engine speed; a GTech meter might help too. At the very least you could try some 0-80 mph runs using a stopwatch.
 
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Discussion Starter #14
yes i read the 3rd gen thing when he posted it and about the rev limiter i was just curius wasn't implying it was the probley
 
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Discussion Starter #15
ok one more little tid bit of info if i close the topic will the administrator delete it ive gotten all the info i need youve all been very helpfull and i appreciate it im not quite sure how this works
 
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Discussion Starter #16
It would be helpful in the future if you learned how to use punctuation. That would be commas and periods. :D
 
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Discussion Starter #17
my language skills are garbage. i wouldnt know where to put a comma.
 
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Discussion Starter #18
I put a comma where there is a slight pause in what I am saying. For example, this sentence gets a comma. I don't know if its right or not but oh well. I always have one of our clerical staff read anything I am sending to a customer because I don't trust my language skills entirely.
 
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Discussion Starter #19
you guyz are great. thanx for pionting me in the right direction im doing the fp mod now,
its going off without a hitch, just going back out to reassemble now!!
 
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Discussion Starter #20
oh life couldnt get much better getting a fuel pump out of a friendz wreched 96 caprice tonight
 
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