GT/GA or GT/HA Question(s)

ccm399 · 03-17-2009, 08:12 PM

Hi all, great forum!

I have been researching on here and well, pretty much all over the net to try and nail down some specifics about building a car for the above class(es). I am thinking about starting with a 3rd gen Cavalier, 3rd gen Grand Am or maybe a Pontiac Sunfire. All have a 104" so the choice will probably come down to what I can find in good shape to start the build.

What is the most popular front suspension used to replace the stock front suspension? I found the AJE struts but I am looking for options.

My second question would be what would be a good engine combo to start with?
The NHRA rule book says I can run any year engine I want so I guess the choices are wide open. I am leaning toward the '68 300/327 but I am thinking that combo might be a bit tough. Also, I see that there are a few aftermarket heads on the runner volume list but I am having a hard time figuring out when/if I can use them. I did find a LITTLE info that suggests that they (the aftermarket heads) add 30hp to the engine combo but I cannot find additional info on the subject. Is this right?

One last thing, if I build the car to NHRA GT/GA specs will it be legal for IHRA SSGT/GA? All the indexes are the same between the NHRA and the IHRA so I would hope the cars would cross over but you never can tell.

This is my first post on here so I'll stop there! Thanks in advance for any and all input / advice.

Thanks,

Chris

rx dealer · 03-18-2009, 06:54 AM

Chris welcome to the site...

It's much easier and cheaper in the long run to buy a ready race car. Go to racingjunk.com look under drag cars then super stock and there are some great deals to be found. Go with 350/255 or 327/275 combo and don't ever use anything but a Stick transmission. Good luck and have fun...Luke

stefan callender · 03-18-2009, 04:48 PM

Give Joe Franco a call, probably the fastest GT/HA car in the country. 631-445-5302. 85 Camaro with a EFI 305.

ccm399 · 03-18-2009, 08:05 PM

Thanks for the comments guys!

Luke, I love your passion for the stick shift car but my leg and hand can NEVER agree on exactly when the gear changes should happen. Automatic for me!

While I am sure I could buy a car cheaper I would much rather build one from scratch. I good friend of mine builds chassis's for a living and he has already offered to let me use the shop, equipment and his skills so the car will not cost me any more then the tubing and parts. We have built class cars before so this will not be our first attempt at a class car. Might be our first GT/HA car but I am sure our modified project will help a ton. We set the BB/AA 1/8 and 1/4 mile ET and speed records for IHRA modified in 2000 (I believe).

I bring 15+ years of engine building to the table as well. I have access to a full automotive machine shop so I can build whatever I want again for only the cost of parts. I do plan to buy some of the "big ticket" used like tranny and converter maybe a 3rd member things like that.

I have gotten lots of great advice thanks to all! Please keep your suggestions coming. Other than not buying a used car (and the above mentioned issue with stick shift transmissions) I would love more input and advice.

I believe the idea of the smaller engines is a good one, I have wanted to mess with a 305 for quite some time now...maybe now's the time. I do not see the 601 casting number heads for any of the combos though. I thing the 993 are close but the chamber on the 601 is a little nicer.

Chris

Oh, one last thing, I do not have a lump some of $$$ to plop down for a used car, I plan to build this for a possible LATE '09 but most likely an 2010 debut.

ccm399 · 03-25-2009, 08:32 AM

Hi all,

I wanted to take a quick second and thank the helpful members of this board. I have been E-mailing back and forth with some of you quite regularly and the advice has been GREAT.

After further review it looks like I need to make a small change in the class(es) I plan run and this rules out HA. So the car will be setup for CA - GA. I plan to run a 305, probably the 1980 305/180 that is GT factored at 250HP.

I understand the 305's like/need a lot of gear both in the trans and the rear end. Can any of the 305 guys shed a little light on this for me. I contacted the NHRA about a couple things one of which was the trans and they told me I need to run a 3 speed but do I need/want the 2.75 first gear of the TH350? Also, does a 6.00 or 6.20 gear sound about right for the rear end (with a 14.5 x 33 Hoosier).

I guess this would be a great time to ask what tire the 305 guys recommend too! I was thinking that particular Hoosier because it is the light weight carcass tire. Maybe I should look for a slightly smaller tire to reduce the amount of power needed to drive the tire? My reasoning was with all that starting line ration I would probably need a large contact patch to help traction (especially on marginal tracks). What about the radial slicks, they were not out in the larger sizes when I raced some years back. Any input on them?

As always thanks for the help!

Chris

03-17-2009, 08:12 PM	#1
ccm399 Junior Member Join Date: Jan 2009 Posts: 3 Likes: 0 Liked 0 Times in 0 Posts	GT/GA or GT/HA Question(s) Hi all, great forum! I have been researching on here and well, pretty much all over the net to try and nail down some specifics about building a car for the above class(es). I am thinking about starting with a 3rd gen Cavalier, 3rd gen Grand Am or maybe a Pontiac Sunfire. All have a 104" so the choice will probably come down to what I can find in good shape to start the build. What is the most popular front suspension used to replace the stock front suspension? I found the AJE struts but I am looking for options. My second question would be what would be a good engine combo to start with? The NHRA rule book says I can run any year engine I want so I guess the choices are wide open. I am leaning toward the '68 300/327 but I am thinking that combo might be a bit tough. Also, I see that there are a few aftermarket heads on the runner volume list but I am having a hard time figuring out when/if I can use them. I did find a LITTLE info that suggests that they (the aftermarket heads) add 30hp to the engine combo but I cannot find additional info on the subject. Is this right? One last thing, if I build the car to NHRA GT/GA specs will it be legal for IHRA SSGT/GA? All the indexes are the same between the NHRA and the IHRA so I would hope the cars would cross over but you never can tell. This is my first post on here so I'll stop there! Thanks in advance for any and all input / advice. Thanks, Chris

03-18-2009, 06:54 AM	#2
rx dealer Member Join Date: Mar 2007 Location: Lake Orion, Michigan Posts: 337 Likes: 12 Liked 53 Times in 13 Posts	Re: GT/GA or GT/HA Question(s) Chris welcome to the site... It's much easier and cheaper in the long run to buy a ready race car. Go to racingjunk.com look under drag cars then super stock and there are some great deals to be found. Go with 350/255 or 327/275 combo and don't ever use anything but a Stick transmission. Good luck and have fun...Luke

03-18-2009, 04:48 PM	#3
stefan callender Senior Member Join Date: Dec 2002 Location: zoo york Posts: 572 Likes: 3 Liked 2 Times in 2 Posts	Re: GT/GA or GT/HA Question(s) Give Joe Franco a call, probably the fastest GT/HA car in the country. 631-445-5302. 85 Camaro with a EFI 305.

03-18-2009, 08:05 PM	#4
ccm399 Junior Member Join Date: Jan 2009 Posts: 3 Likes: 0 Liked 0 Times in 0 Posts	Re: GT/GA or GT/HA Question(s) Thanks for the comments guys! Luke, I love your passion for the stick shift car but my leg and hand can NEVER agree on exactly when the gear changes should happen. Automatic for me! While I am sure I could buy a car cheaper I would much rather build one from scratch. I good friend of mine builds chassis's for a living and he has already offered to let me use the shop, equipment and his skills so the car will not cost me any more then the tubing and parts. We have built class cars before so this will not be our first attempt at a class car. Might be our first GT/HA car but I am sure our modified project will help a ton. We set the BB/AA 1/8 and 1/4 mile ET and speed records for IHRA modified in 2000 (I believe). I bring 15+ years of engine building to the table as well. I have access to a full automotive machine shop so I can build whatever I want again for only the cost of parts. I do plan to buy some of the "big ticket" used like tranny and converter maybe a 3rd member things like that. I have gotten lots of great advice thanks to all! Please keep your suggestions coming. Other than not buying a used car (and the above mentioned issue with stick shift transmissions) I would love more input and advice. I believe the idea of the smaller engines is a good one, I have wanted to mess with a 305 for quite some time now...maybe now's the time. I do not see the 601 casting number heads for any of the combos though. I thing the 993 are close but the chamber on the 601 is a little nicer. Chris Oh, one last thing, I do not have a lump some of $$$ to plop down for a used car, I plan to build this for a possible LATE '09 but most likely an 2010 debut.

03-25-2009, 08:32 AM	#5
ccm399 Junior Member Join Date: Jan 2009 Posts: 3 Likes: 0 Liked 0 Times in 0 Posts	Re: GT/GA or GT/HA Question(s) Hi all, I wanted to take a quick second and thank the helpful members of this board. I have been E-mailing back and forth with some of you quite regularly and the advice has been GREAT. After further review it looks like I need to make a small change in the class(es) I plan run and this rules out HA. So the car will be setup for CA - GA. I plan to run a 305, probably the 1980 305/180 that is GT factored at 250HP. I understand the 305's like/need a lot of gear both in the trans and the rear end. Can any of the 305 guys shed a little light on this for me. I contacted the NHRA about a couple things one of which was the trans and they told me I need to run a 3 speed but do I need/want the 2.75 first gear of the TH350? Also, does a 6.00 or 6.20 gear sound about right for the rear end (with a 14.5 x 33 Hoosier). I guess this would be a great time to ask what tire the 305 guys recommend too! I was thinking that particular Hoosier because it is the light weight carcass tire. Maybe I should look for a slightly smaller tire to reduce the amount of power needed to drive the tire? My reasoning was with all that starting line ration I would probably need a large contact patch to help traction (especially on marginal tracks). What about the radial slicks, they were not out in the larger sizes when I raced some years back. Any input on them? As always thanks for the help! Chris