Tim240z Posted July 8, 2004 Share Posted July 8, 2004 I know, I know...not another "what heads should I buy" question, but here goes anyways: This will go into my 40 Chevy: I have a 71 4 bolt '010' block from my truck. I believe that the engine is unmolested. I want to build a mild high torque, lower range RPM engine, with good reliability and fuel economy. The engine will likely not ever see over 4k RPM, at least not for long. This will be a cruiser with a 200 4R. On the other hand I don't want it to be a complete dog either. I am running Vortec heads on the truck now and love them, but I can't use the Vortecs with the LT1 intake (which I am converting to run a rear mount distributor). I will be using the injectors and running MegaSquirt (which I have already built and bench tested) to run the injectors. I was leaning towards the generic and ubiquitous Edelbrock performer heads, but maybe there is a better choice. Obviously, considering the above requirements, I don't want heads with huge ports, and they will need to be compatable with the LT1 intake ports (which the Vortecs, and some others **see below** are not). Thanks..... Tim From the LT1intake.com site: Will the LT1 intake fit my standard SBC heads? I have test fit the intake on several different types of heads including stock early and late bolt pattern, Trick Flow, and AFR. Due to the dozens of heads available for the SBC I cannot test fit them all. Some heads that have had recent problems are Dart and Sportsman II heads. The coolant ports and EGR port is much larger and the isn't enough intake flange to cover the larger holes. Seems like to me some material would need to be welded to the LT1 intake to provide additional coverage of these larger holes. Will the LT1 intake fit Vortec heads? No, it will not fit. The intake mating flange is too narrow to cover the tall ports that the Vortec head uses. Here's a cutaway picture with a standard SBC intake mated to Fastburn heads. Fastburn heads were drilled with both standard SBC and Vortec bolt patterns. The LT4 intake will not fit Vortec heads either. This is due to the Vortec bolt pattern is way too high on the head for the intake. The LT4 intake can be adapted to Fastburn heads because it is drilled for bother standard and Vortec bolt patterns. Some port matching on the LT4 intake will be requires when using Fastburn heads will be required. Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted July 8, 2004 Share Posted July 8, 2004 I know' date=' I know...not another "what heads should I buy" question, but here goes anyways: This will go into my 40 Chevy: I have a 71 4 bolt '010' block from my truck.., I want to build a mild high torque, lower range RPM engine, with good reliability and fuel economy.., The engine will likely not ever see over 4k RPM, at least not for long.., This will be a cruiser with a 200 4R.., I was leaning towards the generic and ubiquitous Edelbrock performer heads, but maybe there is a better choice. Obviously, considering the above requirements, I don't want heads with huge ports, and they will need to be compatable with the LT1 intake ports.., Thanks,Tim.., [/quote'] Hey Timbo, For a pure street engine there is nothing wrong with the Edelbrock Performer heads. If you want all out WOT heads then you would look to the more expensive heads. But for a low rpm pure street - torquey head the Edelbrock's are great at what they do....and that is make good torque down low due to smaller ports. They definately dont flow as well as other heads yet very few aftermarket performance aluminum head mfg's are going to make 160 cc intake port SBC heads. With the Edelbrock heads you should make in the neighborhood of 315-350 Flywheel HP at peak rpms...which should be in the 4200-5000 rpm range providing you go with a moderate cam profile in the 250 duration, .440" lift, and 112 or 114 Lobe Separation Angle. I think you will be pleasantly surprised with an engine like this. Airflow velocity will be high due to the smaller ports. Couple that with a mild cam profile the cylinder pressures will also be higher earlier in the rpm range...hence the probable 4500-5000 rpm peak hp range. Edelbrock heads are designed to keep airflow velocity high in the ports regardless of rpm: whereas the other aluminum aftermarket mfg's went for the "H/O-Moderate Dragster" engine and this is why most other aluminum aftermarket mfg's, on average, will utilize intake ports larger than Edelbrock: this is why the Edelbrock heads often get overlooked. You could always go AFR and TFS for better flowing heads, but then you would be paying a premium price for an engine you wont be rev'g beyond 4000rpms: so what would be the point? Anyway-this is just my .02c's worth. Kevin, (Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
DavyZ Posted July 9, 2004 Share Posted July 9, 2004 Tim, Kevin makes some good points, especially since this engine won't be seeing over 5000 rpm. The Performers will also lose some weight from the front end. I bought some used Permoer RPMs from a guy in the forum last year, but have yet to install them. I like them just fro the looks! I figure that with 10:1 compression and all the other goodies I have, the cam should make the combo worth 350 hp at the flywheel. Good enough for my first engine. Good luck! Davy Quote Link to comment Share on other sites More sharing options...
Tim240z Posted July 9, 2004 Author Share Posted July 9, 2004 Thanks Kevin!! (and Davy!). I guess since I get Edelbrock stuff at wholesale, the decision is easy!! I will keep the compression down to about 9.0-9.5:1 max for increased torque and reliability and lower temps...... Quote Link to comment Share on other sites More sharing options...
LS1240Z Posted July 9, 2004 Share Posted July 9, 2004 Hey Tim,you still interested in the LS1 swap? Quote Link to comment Share on other sites More sharing options...
Tim240z Posted July 9, 2004 Author Share Posted July 9, 2004 Yes...but only one thing at a time..... Quote Link to comment Share on other sites More sharing options...
LS1240Z Posted July 9, 2004 Share Posted July 9, 2004 Glad to hear that.Let e know if you need help........ Quote Link to comment Share on other sites More sharing options...
DaleMX Posted July 9, 2004 Share Posted July 9, 2004 AFR is my choice in heads. https://www.sslpage.com/aca/catalog/product_info.php?products_id=146 Works with your intake. Dale Quote Link to comment Share on other sites More sharing options...
Tim240z Posted July 9, 2004 Author Share Posted July 9, 2004 AFR is my choice in heads. https://www.sslpage.com/aca/catalog/product_info.php?products_id=146 Works with your intake. Dale That one is for an LT1 engine.....I'm just using the intake from an LT1, the bottom end is old school (71 truck) Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted July 10, 2004 Share Posted July 10, 2004 The AFR's are very nice heads, you just have to understand what it will do to the power band's peak rpm's. It will push the peak hp rpm's into the 5500-6000 rpm range. The point Tim expressed in his initial post was that he would rarely rev this engine past 4000 rpms. This is where Cyl. Head selection must match the intended purpose of the engine-car combo. This requires understanding what the intended purpose of the engine-car combo is PRIOR to picking any engine components. In Tim's case, the AFR's would not benefit his desired lower peak rpm range. Kevin, (Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
DaleMX Posted July 10, 2004 Share Posted July 10, 2004 You can get the AFR's with 180cc intake ports, thats why I posted it. Dont know about head swaping on a 71 small block though. I did the quick read and assumed an LT1. I see the edelbrocks are 165cc to 170cc and would no doubt be a wise choice. Dale Quote Link to comment Share on other sites More sharing options...
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