LT4 VS stock P&P heads
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From: Decatur, TN (N-W of Athens)
Originally Posted by T/ALT1
If you want some ported LT4 heads, i have a pair of LT4 Trickflows that are fully ported by Lloyd Elliott and the LT4 intake to go with it. The intake has been modified and ported to fit the heads nicely. I have over $3grand tied up in the set and have been 11.15@121mph N/a, 9.83@136mph on NX175. So for $2,300 I'll sell this proven setup b/c we are trying a LE3 LT1 heads,cam, intake on my car just to see how fast I can run with there stuff. If I don't sell the heads/intake soon I will just swap cams and go back racing as usaul. LMK Later Clint
HAH! My name is Clint too
I think $2300 is a good deal if you're selling the heads and intake for that price. (That was my understanding). If you(95bFormula) are going to spend money on LT4 stuff, you might as well get what T/ALT1 has, since he is right, it's pretty well proven. Sure his setup will differ from yours a wee bit, so it won't be a carbon copy, but I can't imagine you being disappointed.
Originally Posted by Ed Wright
Originally Posted by 1997bird
Our stock heads have a thin deck surface on them. After 500 HP or 11.5:1 compression it is advised not to run them due to cracking the head surface.
Guess I'm on borrowed time, 527 at the wheels, and 14-1 compression.
I have not heard of a cracking problem.
Hear about that from somebody selling aftermarket heads? <G>
http://www.fastchip.com/Ed-995.mpg
Originally Posted by 1997bird
I do not have any track times yet with this motor. I am just putting miles onto right now to break the motor in first, then I will take it to the track. As far as the 195's SUCKING, I would have to disagree with you there. Some time's that I do have with the 195 head are in a 67' Camaro. The heads are a Comp. port 195 cc int runner head(convetional 23* heads have the same flow as our LT-1/LT-4) that are bolted to a 10.0:1 355 cid HR cam motor. On a engine dyno it made 502 HP. The car has a TH-350 tranny with a 3800 rpm stall converter and a 12 bolt with 4.11 rear gears. It has a Victor Jr. intake on it with a 850 cfm Mighty Demon carb. In Pheonix, AZ it runs 12.9 to 13.2 in the 1/4 on motor and a consistant 10.44 1/4 on a 225 shot of N2O.
Our stock heads have a thin deck surface on them. After 500 HP or 11.5:1 compression it is advised not to run them due to cracking the head surface.
Our stock heads have a thin deck surface on them. After 500 HP or 11.5:1 compression it is advised not to run them due to cracking the head surface.
I am running 11.5:1 on a stock shortblock LT1 and have run 11.9 NA granted I am at about 700ft where Pheonix is about 1400ft. but I would say your results prove MY POINT as the Camaro is lighter than my Caprice and my Caprice has the crappy LT1 intake so many of you want to ditch
. Oh and just 3400 stall 3.73 gears, it runs 12.9 in the hottest most humid weather Wisconsin gets in a bad summer. Thing is daily driver mellow too. Heads have not cracked and I bet tested under the same conditions as yours was on an engine dyno it makes more power. People do not understand just how much installation in a chassis takes away not just drivetrain losses but intake and exhaust restriction as well, and accessories. A reputable LT1 longblock vendors 440hp package is known to put 320-330 to the ground through a 4L60E so your 502hp 355 is going to be comfortably under 400rwhp through that TH400.Good to see Ed in the 9s now too but I would have to say even his car makes a point about the LT1 heads being the better choice, compare his car to Rick Abare's once and while there are certainly differences aside from the heads, I think it looks pretty damn good for the LT1 heads OVER the ported LT4s.
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From: Decatur, TN (N-W of Athens)
Originally Posted by Captainofiron
Man, 96capricemgr and Ed you guys are the Man or uh Men.
I wish I had the time to fix up my TA more.
I wish I had the time to fix up my TA more.
11 Second Club
Joined: Feb 2002
Posts: 955
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From: Silver Spring, Md.
This really is an interesting post. I think it would be interesting to see what kind of dyno numbers have been achieved with most of these h/c packages. I know dyno numbers don't tell the entire story but it would be a good starting point.
My numbers were achieved with 5 year old ARE ported lt1 heads and a gm846 cam.
Alot of you guys have done well with your setups. I'm pleased to see that you guys haven't given up on your lt1s and jumped over to the other side.
My numbers were achieved with 5 year old ARE ported lt1 heads and a gm846 cam.
Alot of you guys have done well with your setups. I'm pleased to see that you guys haven't given up on your lt1s and jumped over to the other side.
People often spend a lot of extra money on things that do not offer much gain. I have a good CAI, used 58mm TB and f-body MAF, the AI topend on a stock shortblock, Clear Image "budget" headers, 2.5" x-pipe added Dynomax catback, Edge converter(cheaper than Yank or Vig because it does not use the overkill billet cover), ProBuilt Automatics tranny, 3.73s(for a few more hours), Eaton posi, used Inland Empire DS. My slicks are mounted on OLD steel Keystones I paid $15 apiece for. Does that all add up to a lot of money yes but notice what I HAVE NOT bought, no electric WP, no lightweight or underdrive damper, or light wheels, no dyno tune, no ignition box, no lightweight bumpers or tranny crossmembers as the Impala guys often do, the list goes on. In the end I have less in my car than most of those who run competitive times with this car.
My point is we all just need to do more OBJECTIVE research before buying, there are some very knowledgable folks here who will not only admit their sucesses but their failures those are the guys to pay attention too, thing is those guys are the minority and you have to figure out who they are and how the info they share can help your goals be achieved.
My point is we all just need to do more OBJECTIVE research before buying, there are some very knowledgable folks here who will not only admit their sucesses but their failures those are the guys to pay attention too, thing is those guys are the minority and you have to figure out who they are and how the info they share can help your goals be achieved.
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Originally Posted by Ed Wright
Guess I'm on borrowed time, 527 at the wheels, and 14-1 compression.
I have not heard of a cracking problem.
Hear about that from somebody selling aftermarket heads? <G>
http://www.fastchip.com/Ed-995.mpg
I have not heard of a cracking problem.
Hear about that from somebody selling aftermarket heads? <G>
http://www.fastchip.com/Ed-995.mpg
Originally Posted by 96capricemgr
I am running 11.5:1 on a stock shortblock LT1 and have run 11.9 NA granted I am at about 700ft where Pheonix is about 1400ft. but I would say your results prove MY POINT as the Camaro is lighter than my Caprice and my Caprice has the crappy LT1 intake so many of you want to ditch . Oh and just 3400 stall 3.73 gears, it runs 12.9 in the hottest most humid weather Wisconsin gets in a bad summer. Thing is daily driver mellow too. Heads have not cracked and I bet tested under the same conditions as yours was on an engine dyno it makes more power. People do not understand just how much installation in a chassis takes away not just drivetrain losses but intake and exhaust restriction as well, and accessories. A reputable LT1 longblock vendors 440hp package is known to put 320-330 to the ground through a 4L60E so your 502hp 355 is going to be comfortably under 400rwhp through that TH400.
Good to see Ed in the 9s now too but I would have to say even his car makes a point about the LT1 heads being the better choice, compare his car to Rick Abare's once and while there are certainly differences aside from the heads, I think it looks pretty damn good for the LT1 heads OVER the ported LT4s.
. Oh and just 3400 stall 3.73 gears, it runs 12.9 in the hottest most humid weather Wisconsin gets in a bad summer. Thing is daily driver mellow too. Heads have not cracked and I bet tested under the same conditions as yours was on an engine dyno it makes more power. People do not understand just how much installation in a chassis takes away not just drivetrain losses but intake and exhaust restriction as well, and accessories. A reputable LT1 longblock vendors 440hp package is known to put 320-330 to the ground through a 4L60E so your 502hp 355 is going to be comfortably under 400rwhp through that TH400.Good to see Ed in the 9s now too but I would have to say even his car makes a point about the LT1 heads being the better choice, compare his car to Rick Abare's once and while there are certainly differences aside from the heads, I think it looks pretty damn good for the LT1 heads OVER the ported LT4s.
11 Second Club
Joined: Feb 2002
Posts: 955
Likes: 4
From: Silver Spring, Md.
Originally Posted by 1997bird
Yes the Camaro is lighter than your Caprice, by about 900 lbs. His TH-350 was transfering about 350 rwhp before the N2O. Good to hear you have a killer set up on your car. I will get out of the pissing match with you, besides I got you beat by four inchs off of the starting line.
This caprice is extremely impressive for the mods done. I know of one in my area that had a 383 with some very good heads and cam, and it wasn't running as well as this one.
Originally Posted by big dave
I don't think the difference in weight is as much as you stated...but, 4-500 lbs is still a considerable amount.
This caprice is extremely impressive for the mods done. I know of one in my area that had a 383 with some very good heads and cam, and it wasn't running as well as this one.
This caprice is extremely impressive for the mods done. I know of one in my area that had a 383 with some very good heads and cam, and it wasn't running as well as this one.
Good to see Ed in the 9s now too but I would have to say even his car makes a point about the LT1 heads being the better choice, compare his car to Rick Abare's once and while there are certainly differences aside from the heads, I think it looks pretty damn good for the LT1 heads OVER the ported LT4s.
_____________________
Yeah, mostly I have a tighter converter and ten degrees less camshaft and smaller headers. You might also want to talk to Rick about LT4 heads. He told me he is looking for an LT4 intake so he can try a set. Mine still has a broader power band with with the smaller cam & headers, which will limit your RPM range. Rick's power peaks at 7300, mine at 7800. That, my dear, is runner volume. 215cc vs 190 or 200. This Tulsa track does not hook like many of the faster tracks. If I had my English Town 60' time, that 9.95 would have been a 9.89. Extending the usable RPM range always makes the car faster, if you know how to use it correctly.
I don't know how many different size and configuration actual race engines you have built and raced, but you certainly seem to consider yourself an expert on these things.
Still, if somebody is going to keep the factory PCM, with it's RPM limitations, I probably would not bother with LT4 heads on a 383". The difference didn't show up for Rick & I until we went to aftermarket computers. The difference shows up AFTER 7000 RPM, at least with our 383"s. I would be suprised if you saw a whole lot with a 396" below 7000. I'm talking heads ported by a higher-end cylinder head shop, not some guy down the block that got a flow bench for Christmas.
_____________________
Yeah, mostly I have a tighter converter and ten degrees less camshaft and smaller headers. You might also want to talk to Rick about LT4 heads. He told me he is looking for an LT4 intake so he can try a set. Mine still has a broader power band with with the smaller cam & headers, which will limit your RPM range. Rick's power peaks at 7300, mine at 7800. That, my dear, is runner volume. 215cc vs 190 or 200. This Tulsa track does not hook like many of the faster tracks. If I had my English Town 60' time, that 9.95 would have been a 9.89. Extending the usable RPM range always makes the car faster, if you know how to use it correctly.
I don't know how many different size and configuration actual race engines you have built and raced, but you certainly seem to consider yourself an expert on these things.
Still, if somebody is going to keep the factory PCM, with it's RPM limitations, I probably would not bother with LT4 heads on a 383". The difference didn't show up for Rick & I until we went to aftermarket computers. The difference shows up AFTER 7000 RPM, at least with our 383"s. I would be suprised if you saw a whole lot with a 396" below 7000. I'm talking heads ported by a higher-end cylinder head shop, not some guy down the block that got a flow bench for Christmas.
Ed I did not mean to offend you and do not claim to build race engines just make good observations in my quest to go faster with my slowass true street car.
Want to talk what ifs, what if Rick made full use of the 138mph trap speed?
Either way it is great to see the BOTH of you in the 9s NA on LTx components without resorting to converted gen 1 heads or carbed intakes, you are setting the record straight on what these components truely are capable of.
In the end though you seem to at least to a point agree with me that ported LT1s are the right choice for most folks, not many are looking to built a 7500+rpm stroker.
Want to talk what ifs, what if Rick made full use of the 138mph trap speed?
Either way it is great to see the BOTH of you in the 9s NA on LTx components without resorting to converted gen 1 heads or carbed intakes, you are setting the record straight on what these components truely are capable of.
In the end though you seem to at least to a point agree with me that ported LT1s are the right choice for most folks, not many are looking to built a 7500+rpm stroker.
I am playing with my tranny right now, Dana set it up for my then 13 second aspirations(3 years ago) and I am tweaking the Transgo setup to suit the current performance. See here is another place where RESEARCH pays off, yourself Rick and I all settled on the same tranny, I bought this one from Dana long before I knew who Rick was or that you used a ProBuilt tranny. I think most folks here would say the 4L60E can not handle what I am throwing at it much less you two, they would be wrong though, just need to know who to talk too.
Seriously I did not meant to diminish your accomplishment my point was more to dispell the "have to have big heads to go fast" myth. I understand given high rpms port volume can be a good thing but given the pcms rather low rpm threshold we can not utilize it if staying with the stock computer.
There is a pretty big static compression difference between yours and Rick's motors as well as all the other stuff already touched on so it can not be an apples to apples comparison on the heads alone I understand that.
Back to my ATF drip bath.
Seriously I did not meant to diminish your accomplishment my point was more to dispell the "have to have big heads to go fast" myth. I understand given high rpms port volume can be a good thing but given the pcms rather low rpm threshold we can not utilize it if staying with the stock computer.
There is a pretty big static compression difference between yours and Rick's motors as well as all the other stuff already touched on so it can not be an apples to apples comparison on the heads alone I understand that.
Back to my ATF drip bath.
The LT4 heads actually work just fine on a 350. You just need to run enough cam, etc. On my Stocker a set of untouched LT4 heads were worth a solid tenth in ET.
Woodro Josey ran 9.80's with ported LT4 heads, a gasket matched intake, stock throttle body, and a .525 cam a few years back at approx. 3000lbs. That's with a .060 over 350 running IHRA Top Stock.
Combination is everything.
Take Care,
Daren
Woodro Josey ran 9.80's with ported LT4 heads, a gasket matched intake, stock throttle body, and a .525 cam a few years back at approx. 3000lbs. That's with a .060 over 350 running IHRA Top Stock.
Combination is everything.
Take Care,
Daren
Originally Posted by Ed Wright
Probably spinning it over 7000, right? Factory PCMs won't do that.
Originally Posted by Ed Wright
They are talking ported LT1 vs LT4, stock LT4s would be faster than stock LT1s.
No offence meant, but there are way too many statements on here that have little real experience behind them.
Take Care,
Daren
Darren,
I changed computers a few weeks ago so I could get past 7000 RPM. As small as my cam is, it was still climbing at a decent rate when the factory PCM threw up it's hands. I found my power peaked at 7200, and held flat 'till 7800, then tapered off some. Right now I'm shifting it at 7900, even though it doesn't stop pulling until about 8300, it runs no faster shifting it higher than 7900. You guys run more can than I do, but I have ported heads.
Stock LT4 heads are certainly faster than stock LT1s, but in my experience not as fast as well ported LT1s. Ported LT4s have not been as fast as properly ported LT1 heads on 355" engines, even though they make good peak numbers. None I have seen so far make as much power at 5200/5400, which is where most fall to on gear changes, thus they do not go down the track as quick.
I could have also been lied to by the son of a man I used to race (who was using Woodrow's engines), about where he was shifting his LT1 Stocker. He told me he shifted his at 7400. Jeff Warren told me where he shifts his, and both shifts (If he wasn't pulling my leg) are below 7000. I wondered why so much difference.
I changed computers a few weeks ago so I could get past 7000 RPM. As small as my cam is, it was still climbing at a decent rate when the factory PCM threw up it's hands. I found my power peaked at 7200, and held flat 'till 7800, then tapered off some. Right now I'm shifting it at 7900, even though it doesn't stop pulling until about 8300, it runs no faster shifting it higher than 7900. You guys run more can than I do, but I have ported heads.
Stock LT4 heads are certainly faster than stock LT1s, but in my experience not as fast as well ported LT1s. Ported LT4s have not been as fast as properly ported LT1 heads on 355" engines, even though they make good peak numbers. None I have seen so far make as much power at 5200/5400, which is where most fall to on gear changes, thus they do not go down the track as quick.
I could have also been lied to by the son of a man I used to race (who was using Woodrow's engines), about where he was shifting his LT1 Stocker. He told me he shifted his at 7400. Jeff Warren told me where he shifts his, and both shifts (If he wasn't pulling my leg) are below 7000. I wondered why so much difference.