ARP bolt lengths
Thread Starter
Burning Brakes
Joined: Sep 2017
Posts: 1,065
Likes: 63
From: Belgium
ARP bolt lengths
Hey everyone
I have some questions regarding the bolt lengths for my intake manifold and the auto trans pan:
1. Intake:
In a previous thread 'HeadsU.P. recommended the ARP-434-2101 bolt kit which are 1" UHL.
I've measured an original intake bolt and it is 1 1/8". Also not all the original intake bolts have the same length... I'm affraid that the 1" bolts will be too short because I'm gonna use lock washers.
ARP does also sell another kit with an UHL: 1.250"
https://www.summitracing.com/parts/arp-435-2101/
Will these bolts be too long? I'm concerned because I've read that there can be damage when intake bolts are too long. (It's for a 77 with original L48 heads and a performer intake)
2. Automatic transmission pan th350:
I think of buying these bolts:
https://www.summitracing.com/parts/arp-430-0401/
Will they fit? (I didn't meassure the length of the original bolts before I left for the US...)
I will be using a new aluminum pan:
https://www.summitracing.com/parts/sum-4338856/
I have some questions regarding the bolt lengths for my intake manifold and the auto trans pan:
1. Intake:
In a previous thread 'HeadsU.P. recommended the ARP-434-2101 bolt kit which are 1" UHL.
I've measured an original intake bolt and it is 1 1/8". Also not all the original intake bolts have the same length... I'm affraid that the 1" bolts will be too short because I'm gonna use lock washers.
ARP does also sell another kit with an UHL: 1.250"
https://www.summitracing.com/parts/arp-435-2101/
Will these bolts be too long? I'm concerned because I've read that there can be damage when intake bolts are too long. (It's for a 77 with original L48 heads and a performer intake)
2. Automatic transmission pan th350:
I think of buying these bolts:
https://www.summitracing.com/parts/arp-430-0401/
Will they fit? (I didn't meassure the length of the original bolts before I left for the US...)
I will be using a new aluminum pan:
https://www.summitracing.com/parts/sum-4338856/
Thread Starter
Burning Brakes
Joined: Sep 2017
Posts: 1,065
Likes: 63
From: Belgium
Race Director
Joined: Mar 2016
Posts: 14,227
Likes: 8,026
From: Napa Valley California
Call ARP in Ventura, CA and tell them your intake and head set up.
They have numerous intake manifold bolt sets available depending on your engine model, heads, and make and model intake.
They have numerous intake manifold bolt sets available depending on your engine model, heads, and make and model intake.
Race Director
Joined: Apr 2003
Posts: 19,345
Likes: 654
From: Tampa, Florida
Drop the intake in place. Use a coat hanger or screw driver whatever to probe the holes for length. Subtract a tick to prevent bottoming. I believe its the center 2? bolts on each side that bottom out on pushrods.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
That 13 cent bolt may cost you many pesos later on if it snaps off in the cyl head.
I really frown on people using your corner hardware bolts on engines. The bolt heads are too big restricting the use of box-end or socket movement. The bolt heads tend to gall the aluminum intakes. And last, they look cheap or . . . . . . . . look like shet.
ARPs intake bolts are not expensive. No worries about snapping one. The 12 point are easy to torque. And they look very professional.
ARP: please note I have not received my endorsement check in the mail yet.
I really frown on people using your corner hardware bolts on engines. The bolt heads are too big restricting the use of box-end or socket movement. The bolt heads tend to gall the aluminum intakes. And last, they look cheap or . . . . . . . . look like shet.
ARPs intake bolts are not expensive. No worries about snapping one. The 12 point are easy to torque. And they look very professional.
ARP: please note I have not received my endorsement check in the mail yet.
Thread Starter
Burning Brakes
Joined: Sep 2017
Posts: 1,065
Likes: 63
From: Belgium
What do you guys think of the bolt length?
I'm in the bahama's now so can't measure or call someone succesfully (I'm from Belgium so high cists to call people here).
Original bolt length: 1 1/8"
ARP option A: 1"
ARP: option B: 1.250"
What should I get (best chance of fitting succesfully)?
I'm in the bahama's now so can't measure or call someone succesfully (I'm from Belgium so high cists to call people here).
Original bolt length: 1 1/8"
ARP option A: 1"
ARP: option B: 1.250"
What should I get (best chance of fitting succesfully)?
Race Director
Joined: Apr 2003
Posts: 19,345
Likes: 654
From: Tampa, Florida
What do you guys think of the bolt length?
I'm in the bahama's now so can't measure or call someone succesfully (I'm from Belgium so high cists to call people here).
Original bolt length: 1 1/8"
ARP option A: 1"
ARP: option B: 1.250"
What should I get (best chance of fitting succesfully)?
I'm in the bahama's now so can't measure or call someone succesfully (I'm from Belgium so high cists to call people here).
Original bolt length: 1 1/8"
ARP option A: 1"
ARP: option B: 1.250"
What should I get (best chance of fitting succesfully)?
That being said, I used Moroso 38400 1-1/8 under head 12 point.
https://www.summitracing.com/parts/mor-38400
Last edited by jim2527; Jul 16, 2019 at 11:29 AM.
Thread Starter
Burning Brakes
Joined: Sep 2017
Posts: 1,065
Likes: 63
From: Belgium
Option B. If too long they can be washered or ground down. Your not making short bolts longer.
That being said, I used Moroso 38400 1-1/8 under head 12 point.
https://www.summitracing.com/parts/mor-38400
That being said, I used Moroso 38400 1-1/8 under head 12 point.
https://www.summitracing.com/parts/mor-38400