Iron block VS Alum
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On The Tree
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From: michigan
Re: Iron block VS Alum Well I was down at the PRI HP show down in Indiana a few months ago and was speaking to the people at the lingenfelter booth and was told by them that the Iron is not much stronger at all for the weight gain, they said resleeving or CR5 block are your only alt. for much stronge block. Im shooting for 650-700 rwhp but dont want to sleeve and dont have the $$ for he CR5, so I assume I should just stay with my alum. and build it strong?
On The Tree
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From: FFX, VA
Re: Iron block VS Alum The iron block is cheaper and you get a free larger bore <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> . With the stock crank it is a 366, 4" stroke 370 or so, 4.125" 402. I'm going with the iron block for a couple reasons. I'm paranoid and you get a larger bore. I'll make up the weight with some lightweight front end stuff.
If your on a budget and you want the extra cubes and don't mind the weight difference then take the iron block. The aluminum block has shown it can take the power though.
Adam J
If your on a budget and you want the extra cubes and don't mind the weight difference then take the iron block. The aluminum block has shown it can take the power though.
Adam J
On The Tree
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From: FFX, VA
Re: Iron block VS Alum Everythings the same. You just have to drill a hole for one of the external components. Can't remember what off the top my head though. If you do a search in the internal engine section you should find it.
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From: Raleigh, NC
Re: Iron block VS Alum A boss for the alternator bracket is not drilled. That's the only mod I had to do to the block. Also, I relocated the ground strap on the passenger side. No big deal.
Call Golden West Performance (303-346-5232) to get your questions answered about the iron block vs alum block.
I guess if you can get the horsepower you want without too much overbore or stroke, you'd be ok. I wanted more cubes though. I put down as much RWTQ as some of the turbo's at on 7 PSI.
If you want to bring torque up to match your new horsepower, you've gotta have more cubes.
Call Golden West Performance (303-346-5232) to get your questions answered about the iron block vs alum block.
I guess if you can get the horsepower you want without too much overbore or stroke, you'd be ok. I wanted more cubes though. I put down as much RWTQ as some of the turbo's at on 7 PSI.
If you want to bring torque up to match your new horsepower, you've gotta have more cubes.
Re: Iron block VS Alum 75lbs????? Yeah right! Try 120lbs+ The iron block is heavy. Of course you can always lighten the frontend up. But i'm still going w/ me set up. Check it out....
01 LS1 block
375cid
9:1 CR
6.0L racing heads
Holley manifold
80mm TB
All forged internals
Oh and did i forget TWIN TURBOS @ 10-13PSI BABY!!!!!!
600RWHP+ here i come....... <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" />
01 LS1 block
375cid
9:1 CR
6.0L racing heads
Holley manifold
80mm TB
All forged internals
Oh and did i forget TWIN TURBOS @ 10-13PSI BABY!!!!!!
600RWHP+ here i come....... <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" />
Thread Starter
On The Tree
Joined: Dec 2001
Posts: 168
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From: michigan
Re: Iron block VS Alum Yeah that setup looks sweet, makes me think maybe I should ditch the s/c and 408 stroker idea and get a turbo and do a setup like that? Im looking for a torque monster, hmmm what setup to go with??? Any thoughts.
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Verdad Gallardo Moderator
Joined: Nov 2001
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From: Raleigh, NC
Re: Iron block VS Alum </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Danny:
<strong> 75lbs????? Yeah right! Try 120lbs+ </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Where do you get that figure from? Everyone I've talked to says 70 or 75 lbs heavier.
<strong> 75lbs????? Yeah right! Try 120lbs+ </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Where do you get that figure from? Everyone I've talked to says 70 or 75 lbs heavier.
Thread Starter
On The Tree
Joined: Dec 2001
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From: michigan
Iron block VS Alum Hi, was planning on building a stroker for boost, what would be stronger? Would think the iron but was told that it is not much stronger and for the weight it would not be worth it??? Any info on the pros and cons would be great. Thanks Ryan
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Joined: Nov 2001
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From: Raleigh, NC
Re: Iron block VS Alum I was told by builders I talked to that unless you can afford something like the C5R block, the aluminum block is not strong enough to hold a lot of horsepower. It was recommended to me that if you were building the LS1 for RWHP in excess of 600 RWHP, you should consider a stouter block.
I don't know if the extra 70 pounds makes that much more difference (I know it seems it would, since guys go so far as to move their battery to the trunk and such). But you could spring for the ligher K-member (BMR?), which would lighten it back up.
I guess you have to weigh (no pun intended) the extra power you could safely extract from the iron block compared to what the aluminum block could safely produce.
I weight 190 lbs. I saw a guy racing one day that had to weigh between 250 and 300 lbs. What you gonna do? <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />
Also, I don't know what affect just 70 more lbs. has on the reate of acceleration down to the end of the track. I suppose the only way to know is for someone to put a 70 lb somewhere under the hood and try it with the same power, same car.
Too many factors have changed for me to really compare. I guess if I never anticipate going above 600 RWHP, I would stay Alum. When I can afford to get my fueling right where I can boost it more <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> , I hope to get close to 700 RWHP.But that's about 175 RWHP away righ now. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
I don't know if the extra 70 pounds makes that much more difference (I know it seems it would, since guys go so far as to move their battery to the trunk and such). But you could spring for the ligher K-member (BMR?), which would lighten it back up.
I guess you have to weigh (no pun intended) the extra power you could safely extract from the iron block compared to what the aluminum block could safely produce.
I weight 190 lbs. I saw a guy racing one day that had to weigh between 250 and 300 lbs. What you gonna do? <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />
Also, I don't know what affect just 70 more lbs. has on the reate of acceleration down to the end of the track. I suppose the only way to know is for someone to put a 70 lb somewhere under the hood and try it with the same power, same car.
Too many factors have changed for me to really compare. I guess if I never anticipate going above 600 RWHP, I would stay Alum. When I can afford to get my fueling right where I can boost it more <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> , I hope to get close to 700 RWHP.But that's about 175 RWHP away righ now. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
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Joined: Sep 2002
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From: Clinton Twp. Michigan
Re: Iron block VS Alum Well, i think your 120 lbs is a little on the generous side, it's closer to the 70/75 lbs, whoever told you that, probably sold you the holley intake, dude, do yourself a favor, and sell it, you'll have tons of problems, and heat soak to add it all up.
Re: Iron block VS Alum I haven't been around ls1's for that long so i can only speak from what i have seen on other cars and not my own.However i know a guy that has a twin turbo vette that puts down 700 rw and he drives it HARD and has never had a problem.The car runs low 10s @ 140+ and is very reliable.I think most of the problem is in the tune not the strength of the block.I have seen many guys split a stock 302 block at the 550 hp level and then i have seen some of them live at 650 hp for a long time.
Im building an iron block because it cost almost $3000 for an aluminum block all machined. <img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" />
Im building an iron block because it cost almost $3000 for an aluminum block all machined. <img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" />
10 Second Club
Joined: Apr 2002
Posts: 1,755
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From: Cincinnati, Ohio
Re: Iron block VS Alum Like Chris ARE 360 said, I have talked to Agostino, Katech + others and the high horsepower numbers that are being made with the aluminum blocks prove that they hold up. I am sure that an iron block is stronger but is it neccessary. I feel that because everybody knows that the iron is stronger they feel it is something they need. Can anybody show where an aluminum block failed? Most all super high horse racing motors are now aluminum. When I talked to Agostino they just laughed because of all the high horse motors (800 HP+) they have built and raced over and over that held up fine. If aluminum is doing the job why carry the extra weight?
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Joined: Nov 2001
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From: Raleigh, NC
Re: Iron block VS Alum No one said you couldn't get an Alum block to handle the power... I'm saying it's cheaper to use an iron block and that those race cars you are talking about are using an Alum block designed for racing. It's probably nearly twice the cost.
In your rebuttal, make sure you are talking about an Alum block capable of being bored and stroked to 422 or more CID.
In your rebuttal, make sure you are talking about an Alum block capable of being bored and stroked to 422 or more CID.